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1

Biorthogonal pulse shape modulation for ultra-wideband wireless communications  

Microsoft Academic Search

We propose a wireless communications ultra-wideband (UWB) multiple access spread spectrum scheme based on biorthogonal pulse shape modulation (BPSM). Unlike classical UWB that employs bit-by-bit spreading, this scheme utilizes symbol-by-symbol spreading which effectively reduces the multiple access interference. Compared to orthogonal UWB using symbol-by-symbol spreading the proposed BPSM technique minimizes the receiver complexity, while causing a negligible performance degradation. The

Nejib Boubaker; Khaled Ben Letaief

2004-01-01

2

Ultra-wideband pulse generation using turbo-switches  

NASA Astrophysics Data System (ADS)

We propose and experimentally demonstrate a novel method for generating ultra-wideband (UWB) monocycle pulse by exploiting a turbo-switch which consists of two reflective semiconductor optical amplifiers (RSOAs). By adjusting the currents applied to both RSOAs, the monocycle pulse is realized due to the gain overshoot induced by the turbo-switch. The polarity inversed monocycle pairs and the UWB doublet pulse train are numerically realized by cascading turboswitches.

Zhang, Weiwei; Sun, Junqiang; Cheng, Cheng; Zhang, Xinliang; Huang, Dexiu

2008-11-01

3

All-optical ultra-wideband monocycle pulse generation using polarization state rotation filtering  

NASA Astrophysics Data System (ADS)

We present a novel method to generate ultra-wideband (UWB) monocycle pulses using polarization state rotation filtering of optical negative pulses. Monocycle-like optical pulses with reversed polarities can be generated with appropriate polarization adjustment.

Jiang, Huan; Wen, He; Zheng, Xiaoping; Zhang, Hanyi; Guo, Yili

2008-11-01

4

Ultra Wideband (UWB) communication vulnerability for security applications.  

SciTech Connect

RF toxicity and Information Warfare (IW) are becoming omnipresent posing threats to the protection of nuclear assets, and within theatres of hostility or combat where tactical operation of wireless communication without detection and interception is important and sometimes critical for survival. As a result, a requirement for deployment of many security systems is a highly secure wireless technology manifesting stealth or covert operation suitable for either permanent or tactical deployment where operation without detection or interruption is important The possible use of ultra wideband (UWB) spectrum technology as an alternative physical medium for wireless network communication offers many advantages over conventional narrowband and spread spectrum wireless communication. UWB also known as fast-frequency chirp is nonsinusoidal and sends information directly by transmitting sub-nanosecond pulses without the use of mixing baseband information upon a sinusoidal carrier. Thus UWB sends information using radar-like impulses by spreading its energy thinly over a vast spectrum and can operate at extremely low-power transmission within the noise floor where other forms of RF find it difficult or impossible to operate. As a result UWB offers low probability of detection (LPD), low probability of interception (LPI) as well as anti-jamming (AJ) properties in signal space. This paper analyzes and compares the vulnerability of UWB to narrowband and spread spectrum wireless network communication.

Cooley, H. Timothy

2010-07-01

5

Cognitive Technology for improving Ultra-Wideband (UWB) Coexistence  

Microsoft Academic Search

Cognitive radio technology enables the opportunistic operation of secondary devices in frequency bands allocated to primary users. In this paper we explore how this technology can enable ultra-wideband (UWB) systems to coexist with primary users. The distinguishing aspect of cognitive radio technology is the ability to detect and avoid primary users. We discuss two options for detecting the presence of

S. M. Mishra; R. W. Brodersen

2007-01-01

6

Low Complexity Chirp Pulsed Ultra-Wideband System with Near-Optimum Multipath Performance  

Microsoft Academic Search

This paper describes the Impulse Radio Ultra- Wideband (IR-UWB) system using linear chirp UWB pulses as symbols. The novel method of coherent or differentially coherent detection of chirp pulses in multipath channels is introduced. The method divides detection in the receiver between its analog and digital part; in the analog part of the receiver, received signal is compressed in frequency

Igor Dotlic; Ryuji Kohno

2011-01-01

7

Pulse-based ultra-wideband transmitters for digital communication  

E-print Network

Ultra-wideband radio (UWB) is a rapidly developing wireless technology that promises unprecedented data rates for short-range commercial radios, combined with precise locationing and high energy efficiency. These benefits ...

Wentzloff, David D. (David Dale), 1977-

2007-01-01

8

Modulation Schemes Based on Orthogonal Pulses for Time Hopping Ultra Wideband Radio Systems  

Microsoft Academic Search

This paper describes a combined modulation scheme for time hopping ultra wideband (TH-UWB) radio systems using on-off keying (OOK) and pulse shape modulation (PSM). For this scheme, a set of orthogonal pulses is used to represent bits in a symbol. These orthogonal pulses are transmitted simultaneously in the same time slot resulting in a composite pulse. By assigning different subset

Sudhan Majhi; A. S. Madhukumar; A. Benjamin Premkumar; Francois P. S. Chin

2007-01-01

9

A PPM GAUSSIAN PULSE GENERATOR FOR ULTRA-WIDEBAND COMMUNICATIONS  

E-print Network

A PPM GAUSSIAN PULSE GENERATOR FOR ULTRA-WIDEBAND COMMUNICATIONS Sumit Bagga1 , Giuseppe de Vita2, Pisa, Italy Email: gi.devita@tiscali.it ABSTRACT A Gaussian pulse generator incorporating a pulse position modulator for use in an ultra-wideband or impulse radio system is described. The pulse generator

Serdijn, Wouter A.

10

Photonic Polarity-Switchable Ultra-Wideband Pulse Generation Using a Tunable Sagnac Interferometer Comb Filter  

Microsoft Academic Search

A photonic approach to polarity-switchable ultra-wideband (UWB) pulse generation is proposed. The proposed setup principally consists of an electrooptic phase modulator (EOPM) and a tunable optical comb filter constructed with another EOPM inside a Sagnac interferometer. The comb filter working at its linear region performs the phase-to-intensity conversion to generate UWB pulses with monocycle shape. By adjusting the bias voltage

Jianqiang Li; Kun Xu; Songnian Fu; Ming Tang; P. Shum; Jian Wu; Jintong Lin

2008-01-01

11

Photonic ultra-wideband monocycle pulse generation using a single electro-optic modulator  

Microsoft Academic Search

A compact and low-cost approach to photonic ultra-wideband (UWB) monocycle pulse generation is proposed and experimentally demonstrated based on the wavelength dependence of the half-wave voltage of a Mach-Zehnder modulator (MZM). By employing a single MZM and two laser sources at around 1310nm and 1550nm, a pair of polarity-reversed monocycle pulses with the full width at half maximum (FWHM) of

Songnian Fu; Jianqiang Li; P. Shum

2008-01-01

12

Ultra-wideband short-pulse radar with range accuracy for short range detection  

DOEpatents

An ultra-wideband (UWB) radar transmitter apparatus comprises a pulse generator configured to produce from a sinusoidal input signal a pulsed output signal having a series of baseband pulses with a first pulse repetition frequency (PRF). The pulse generator includes a plurality of components that each have a nonlinear electrical reactance. A signal converter is coupled to the pulse generator and configured to convert the pulsed output signal into a pulsed radar transmit signal having a series of radar transmit pulses with a second PRF that is less than the first PRF.

Rodenbeck, Christopher T; Pankonin, Jeffrey; Heintzleman, Richard E; Kinzie, Nicola Jean; Popovic, Zorana P

2014-10-07

13

Ultra-wideband (UWB) bandpass filters using multiple-mode resonator  

Microsoft Academic Search

A novel microstrip-line ultra-wideband (UWB) bandpass filter is proposed and implemented using a multiple-mode resonator (MMR), aiming at transmitting the signals in the whole UWB passband of 3.1-10.6GHz. In the design, the first three resonant frequencies of this MMR are properly adjusted to be placed quasiequally within the UWB. Then, the parallel-coupled lines at the two sides are longitudinally stretched

Lei Zhu; Sheng Sun; Wolfgang Menzel

2005-01-01

14

Ultra-wideband pulse generation with flexible pulse shape and polarity control using a Sagnac-interferometer-based intensity modulator.  

PubMed

We propose a novel scheme to generate ultra-wideband (UWB) pulse by employing a Sagnac interferometer comprising a phase modulator. This structure performs a dual-input and dual-output intensity modulator (IM), ultimately resulting in the flexibility to select the shape and the polarity of the generated UWB pulse. The experiment results show a good agreement with the theoretical investigation in terms of both pulse profile and spectrum, which conforms to the definition of UWB signals by the U.S. Federal Communications Commission. Furthermore, the proposed scheme is independent of the voltage bias point. PMID:19551113

Li, Jianqiang; Xu, Kun; Fu, Songnian; Wu, Jian; Lin, Jintong; Tang, Ming; Shum, P

2007-12-24

15

A photonic ultra-wideband pulse generator based on relaxation oscillations of a semiconductor laser.  

PubMed

A photonic ultra-wideband (UWB) pulse generator based on relaxation oscillations of a semiconductor laser is proposed and experimentally demonstrated. We numerically simulate the modulation response of a direct modulation laser (DML) and show that due to the relaxation oscillations of the laser, the generated signals with complex shape in time domain match the Federal Communications Commission (FCC) mask in the frequency domain. Experimental results using a DML agree well with simulation predictions. Furthermore, we also experimentally demonstrate the generation of FCC compliant UWB signals by externally injecting a distributed feedback (DFB) laser. PMID:19506617

Yu, Xianbin; Braidwood Gibbon, Timothy; Pawlik, Michal; Blaaberg, Søren; Tafur Monroy, Idelfonso

2009-06-01

16

Power line communications (PLC) using impulse ultra wideband (UWB) in a microprocessor had been  

E-print Network

Abstract Power line communications (PLC) using impulse ultra wideband (UWB) in a microprocessor had microprocessor increases rapidly and seemingly without bound, testing and debug strategies have to be constantly these variations on a microprocessor die, most of the test circuits are either removed once the chip is deployed

Ha, Dong S.

17

Ultra-Wideband Electrical Pulse Generator Using Photoconductive Semiconductor Switches  

Microsoft Academic Search

We achieved the generation of unipolar and bipolar ultra-wideband electrical pulses by using a photoconductive device. It relies on a doped silicon substrate which is used in the linear mode with less optical energy than usually published. This running mode allows the synchronisation of several sources with a timing jitter less than 5 ps. However it permits to control the

B. Vergne; V. Couderc; A. Barthelemy; M. Lalande; V. Bertrand; D. Gontier

2005-01-01

18

An ultra-wideband CMOS low noise amplifier for 3-5GHz UWB system  

Microsoft Academic Search

Abstract—An ultra-wideband (UWB) CMOS low noise amplifier (LNA) topology that combines a narrowband LNA with a resistive shunt-feedback is proposed. The resistive shunt-feedback provides wideband input matching with small noise figure (NF) degradation by reducing the Q-factor of the narrowband LNA input and flattens the passband gain. The proposed UWB amplifier is implemented in 0.18- m CMOS technology for a

Chang-Wan Kim; Min-Suk Kang; Phan Tuan Anh; Hoon-Tae Kim; Sang-Gug Lee

2005-01-01

19

A method of optical ultra-wideband doublet pulse generation based on SOA-XGM and SOA-SGS  

NASA Astrophysics Data System (ADS)

Photonic generation of ultra-wideband (UWB) pulse technology is the key technology of UWB-over-fiber system. The effect of nonlinearity in semiconductor optical amplifier (SOA) is widely applied in the area of all-optical signal processing. A method is proposed to generate UWB doublet pulse using cross-gain modulation (XGM) of SOA and self gain-saturation (SGS) effect of SOA. In this method, the UWB monocycle pulse is generated by SOA-XGM, and the UWB doublet pulse is generated by utilizing the generated UWB monocycle pulse and gain saturation effect of another SOA. According to the proposed method, we obtained the UWB doublet pulse by utilizing photonic simulation software. The center frequency is 4.85GHz and the fraction bandwidth is 122%, it meets the criterion of FCC.

Chen, Xin; Guan, Yalin; Chen, Xinqiao; Yang, Xiaoxue

2013-03-01

20

Filter-free ultra-wideband doublet pulses generation based on wavelength conversion and fiber dispersion effect  

NASA Astrophysics Data System (ADS)

Filter-free ultra-wideband (UWB) doublet pulse generation is experimentally demonstrated in the optical domain based on cross-gain modulation (XGM) in semiconductor optical amplifier (SOA) and UWB-over-fiber technology is implemented by exploiting dispersion-induced pulse broadening effect in single-mode fiber (SMF). In our proposed system, the SOA generates a polarity-inversed Gaussian pulse train with respect to the injected one through the XGM. After a piece of SMF, the bandwidth of polarity-reversed Gaussian pulse broadens due to the induced dispersion. After the combination of the two light waves with a suitable time delay between them, UWB pulse is obtained. The key parameters for UWB pulse, including central frequency, 10 dB bandwidth, as well as fractional bandwidth are experimentally obtained with 8 GHz, 9.9 GHz and 123% respectively. The generated UWB doublet pulse conforms with the UWB definition of Federal Communications Commission (FCC).

Shao, Jing; Sun, Junqiang

2012-06-01

21

Cognospectrum: spectrum adaptation and evolution in cognitive ultra-wideband radio  

Microsoft Academic Search

Cognitive ultra wideband (UWB) radio is proposed to exploit the advantages of combining cognitive radio with ultra wideband technologies. In order to realize cognitive UWB radio, multiple pulse waveform adaptations have been investigated for producing the expected spectral notches while matching with FCC spectral mask and other frequency regulation requirements. To verify the pulse distortion effect of UWB antenna on

Xiaofei Zhou; Kamya Y. Yazdandoost; Honggang Zhang; Imrich Chlamtac

2005-01-01

22

Photonic monocycle pulse generation and modulation for ultra-wideband-over-fiber application  

NASA Astrophysics Data System (ADS)

In order to integrate local ultra-wideband (UWB) environment into fixed wired networks or wireless wide-area infrastructures and eliminate the high cost of microwave electrical circuits or devices, UWB-over-fiber systems have emerged to exploit the advantages offered by optical fiber. We experimentally demonstrate a photonic UWB monocycle pulse generation and pulse position modulation (PPM). The UWB monocycle pulse with inverse polarity can be generated based on the two differently-biased Mach-Zehnder modulators, subsequently the PPM of the UWB monocycle pulse is realized through the nonlinear polarization rotation (NPR) arising in a semiconductor optical amplifier (SOA). We proposed and experimentally demonstrated an effective procedure to generate and maintain a linear output state of polarization (SOP) during the course of the nonlinear polarization rotation (NPR) of an SOA. High performance of polarization switching can be achieved. The proposed scheme is more preferable for the UWB-over-fiber applications due to its compact size and high stability.

Fu, Songnian; Zhong, Wen-De; Shum, P.; Li, Jianqiang; Xu, Kun

2008-11-01

23

Ultra-wideband transmitter research  

Microsoft Academic Search

The generation of ultra-wideband (UWB) pulses is a challenging problem that involves generating pulses with fast rise times on the order of 100 ps and voltages of more than 500 kV. Pulsewidths from 130 ps to a few nanoseconds (ns) are possible. A critical step involves switching high voltages with precision. The use of both gas and oil for the

Forrest J. Agee; Carl E. Baum; William D. Prather; Jane M. Lehr; J. P. O'Loughlin; J. W. Burger; J. S. H. Schoenberg; D. W. Scholfield; R. J. Torres; J. P. Hull; J. A. Gaudet

1998-01-01

24

FDTD analysis of a gigahertz TEM cell for ultra-wideband pulse exposure studies of biological specimens  

Microsoft Academic Search

Gigahertz transverse electromagnetic (GTEM) transmission cells have been previously used to experimentally study exposure of biological cells to ultra-wideband (UWB), monopolar, electromagnetic pulses. Using finite-difference time-domain (FDTD) simulations we examine the time-dependent electric field waveforms and energy dose spatial distributions within a finite volume of biological cell culture medium during these experiments. The simulations show that when one or more

Zhen Ji; C. Hagness; H. Booske; Satnam Mathur; Martin L. Meltz

2006-01-01

25

Photonic generation of UWB pulses with pulse position modulation  

E-print Network

Photonic generation of UWB pulses with pulse position modulation H. Mu and J. Yao A novel photonic approach to generating ultra-wideband (UWB) signals with pulse position modulation (PPM) is proposed-position-modu- lation module to achieve PPM. When a Gaussian pulse train is inputted to the first subsystem, a monocycle

Yao, Jianping

26

Photonic generation of ultra-wideband doublet pulse using a semiconductor-optical-amplifier based polarization-diversified loop.  

PubMed

We propose and demonstrate a novel scheme of ultra-wideband (UWB) doublet pulse generation using a semiconductor optical amplifier (SOA) based polarization-diversified loop (PDL) without any assistant light. In our scheme, the incoming gaussian pulse is split into two parts by the PDL, and each of them is intensity modulated by the other due to cross-gain modulation (XGM) in the SOA. Then, both parts are recombined with incoherent summation to form a UWB doublet pulse. Bi-polar UWB doublet pulse generation is demonstrated using an inverted gaussian pulse injection. Moreover, pulse amplitude modulation of UWB doublet is also experimentally demonstrated. Our scheme shows some advantages, such as simple implementation without assistant light and single optical carrier operation with good fiber dispersion tolerance. PMID:22739860

Luo, Bowen; Dong, Jianji; Yu, Yuan; Yang, Ting; Zhang, Xinliang

2012-06-15

27

Photonic generation of ultra-wideband pulses using a fiber delay interferometer  

NASA Astrophysics Data System (ADS)

We demonstrate a novel scheme to generate ultra wideband (UWB) doublet pulses by inputting a dark return-to-zero (RZ) signal into a fiber delay interferometer (FDI). When a dark RZ pulse train with a repetition rate of 0.625 GHz and a pulse width of 120 ps was inputted into a FDI with a free spectrum range (FSR) of 0.16 nm (~20 GHz, according time delay is ~50 ps) and an extinction ratio (ER) of 9 dB, by adjusting the control temperature of the FDI, the phase difference of the input light on the both fiber arms of the FDI is changed and controlled, UWB doublet pulse is directly generated at the output port of the FDI. The system parameters effects on the output signal were also discussed. Moreover, we numerically demonstrated that, by carefully optimizing system parameters, UWB quadruplet pulses also can be generated. This scheme has some distinct advantages including easy integration, convenient tuning, good stability, and so on. Presented method also accords with the general features in future applied UWB system, namely, single optical source input, simple configuration and passive device.

Wang, Fei; Zhang, Xinliang; Zhang, Yin; Xu, Enming

2011-11-01

28

Photonic generation of ultra-wideband pulses using a fiber delay interferometer  

NASA Astrophysics Data System (ADS)

We demonstrate a novel scheme to generate ultra wideband (UWB) doublet pulses by inputting a dark return-to-zero (RZ) signal into a fiber delay interferometer (FDI). When a dark RZ pulse train with a repetition rate of 0.625 GHz and a pulse width of 120 ps was inputted into a FDI with a free spectrum range (FSR) of 0.16 nm (~20 GHz, according time delay is ~50 ps) and an extinction ratio (ER) of 9 dB, by adjusting the control temperature of the FDI, the phase difference of the input light on the both fiber arms of the FDI is changed and controlled, UWB doublet pulse is directly generated at the output port of the FDI. The system parameters effects on the output signal were also discussed. Moreover, we numerically demonstrated that, by carefully optimizing system parameters, UWB quadruplet pulses also can be generated. This scheme has some distinct advantages including easy integration, convenient tuning, good stability, and so on. Presented method also accords with the general features in future applied UWB system, namely, single optical source input, simple configuration and passive device.

Wang, Fei; Zhang, Xinliang; Zhang, Yin; Xu, Enming

2012-02-01

29

Ultra-wideband receiver  

DOEpatents

An ultra-wideband (UWB) receiver utilizes a strobed input line with a sampler connected to an amplifier. In a differential configuration, .+-.UWB inputs are connected to separate antennas or to two halves of a dipole antenna. The two input lines include samplers which are commonly strobed by a gating pulse with a very low duty cycle. In a single ended configuration, only a single strobed input line and sampler is utilized. The samplers integrate, or average, up to 10,000 pulses to achieve high sensitivity and good rejection of uncorrelated signals.

McEwan, Thomas E. (Livermore, CA)

1994-01-01

30

Ultra-wideband receiver  

DOEpatents

An ultra-wideband (UWB) receiver utilizes a strobed input line with a sampler connected to an amplifier. In a differential configuration, {+-}UWB inputs are connected to separate antennas or to two halves of a dipole antenna. The two input lines include samplers which are commonly strobed by a gating pulse with a very low duty cycle. In a single ended configuration, only a single strobed input line and sampler is utilized. The samplers integrate, or average, up to 10,000 pulses to achieve high sensitivity and good rejection of uncorrelated signals. 21 figs.

McEwan, T.E.

1996-06-04

31

Ultra-wideband receiver  

DOEpatents

An ultra-wideband (UWB) receiver utilizes a strobed input line with a sampler connected to an amplifier. In a differential configuration, [+-] UWB inputs are connected to separate antennas or to two halves of a dipole antenna. The two input lines include samplers which are commonly strobed by a gating pulse with a very low duty cycle. In a single ended configuration, only a single strobed input line and sampler is utilized. The samplers integrate, or average, up to 10,000 pulses to achieve high sensitivity and good rejection of uncorrelated signals. 16 figs.

McEwan, T.E.

1994-09-06

32

Ultra-wideband receiver  

DOEpatents

An ultra-wideband (UWB) receiver utilizes a strobed input line with a sampler connected to an amplifier. In a differential configuration, .+-.UWB inputs are connected to separate antennas or to two halves of a dipole antenna. The two input lines include samplers which are commonly strobed by a gating pulse with a very low duty cycle. In a single ended configuration, only a single strobed input line and sampler is utilized. The samplers integrate, or average, up to 10,000 pulses to achieve high sensitivity and good rejection of uncorrelated signals.

McEwan, Thomas E. (Livermore, CA)

1996-01-01

33

Generation of ultra-wideband triplet pulses based on four-wave mixing and phase-to-intensity modulation conversion.  

PubMed

We propose and demonstrate a novel scheme to generate ultra-wideband (UWB) triplet pulses based on four-wave mixing and phase-to-intensity modulation conversion. First a phase-modulated Gaussian doublet pulse is generated by four-wave mixing in a highly nonlinear fiber. Then an UWB triplet pulse is generated by generating the first-order derivative of the phase-modulated Gaussian doublet pulse using an optical filter serving as a frequency discriminator. By locating the optical signal at the linear slope of the optical filter, the phase modulated Gaussian doublet pulse is converted to an intensity-modulated UWB triplet pulse which well satisfies the Federal Communications Commission spectral mask requirements, even in the extremely power-restricted global positioning system band. PMID:23037074

Li, Wei; Wang, Li Xian; Hofmann, Werner; Zhu, Ning Hua; Bimberg, Dieter

2012-08-27

34

A new UWB pulse generator for FCC spectral masks  

Microsoft Academic Search

We present a pulse design algorithm for acquiring a set of orthogonal ultra-wideband (UWB) impulses with limited time duration subject to a pre-selected frequency mask. The proposed algorithm is simple and numerically sound. The designed UWB pulse shapes are shown to satisfy the recent FCC specification on UWB radio frequency constraints.

A. B. Parr; B. L. Cho; Z. Ding

2003-01-01

35

Emerging Communication Technologies (ECT) Phase 2 Report. Volume 3; Ultra Wideband (UWB) Technology  

NASA Technical Reports Server (NTRS)

The Emerging Communication Technology (ECT) project investigated three First Mile communication technologies in support of NASA s Second Generation Reusable Launch Vehicle (2nd Gen RLV), Orbital Space Plane, Advanced Range Technology Working Group (ARTWG) and the Advanced Spaceport Technology Working Group (ASTWG). These First Mile technologies have the purpose of interconnecting mobile users with existing Range Communication infrastructures. ECT was a continuation of the Range Information System Management (RISM) task started in 2002. RISM identified the three advance communication technologies investigated under ECT. These were Wireless Ethernet (Wi-Fi), Free Space Optics (FSO), and Ultra Wideband (UWB). Due to the report s size, it has been broken into three volumes: 1) Main Report 2) Appendices 3) UWB

Bastin, Gary L.; Harris, William G.; Chiodini, Robert; Nelson, Richard A.; Huang, PoTien; Kruhm, David A.

2003-01-01

36

Adiabatic and fast passage ultra-wideband inversion in pulsed EPR.  

PubMed

We demonstrate that adiabatic and fast passage ultra-wideband (UWB) pulses can achieve inversion over several hundreds of MHz and thus enhance the measurement sensitivity, as shown by two selected experiments. Technically, frequency-swept pulses are generated by a 12 GS/s arbitrary waveform generator and upconverted to X-band frequencies. This pulsed UWB source is utilized as an incoherent channel in an ordinary pulsed EPR spectrometer. We discuss experimental methodologies and modeling techniques to account for the response of the resonator, which can strongly limit the excitation bandwidth of the entire non-linear excitation chain. Aided by these procedures, pulses compensated for bandwidth or variations in group delay reveal enhanced inversion efficiency. The degree of bandwidth compensation is shown to depend critically on the time available for excitation. As a result, we demonstrate optimized inversion recovery and double electron electron resonance (DEER) experiments. First, virtually complete inversion of the nitroxide spectrum with an adiabatic pulse of 128ns length is achieved. Consequently, spectral diffusion between inverted and non-inverted spins is largely suppressed and the observation bandwidth can be increased to increase measurement sensitivity. Second, DEER is performed on a terpyridine-based copper (II) complex with a nitroxide-copper distance of 2.5nm. As previously demonstrated on this complex, when pumping copper spins and observing nitroxide spins, the modulation depth is severely limited by the excitation bandwidth of the pump pulse. By using fast passage UWB pulses with a maximum length of 64ns, we achieve up to threefold enhancement of the modulation depth. Associated artifacts in distance distributions when increasing the bandwidth of the pump pulse are shown to be small. PMID:23434533

Doll, Andrin; Pribitzer, Stephan; Tschaggelar, René; Jeschke, Gunnar

2013-05-01

37

UWB multiple-pulse generator and transmitter  

Microsoft Academic Search

In this paper, a multi-pulse generator which generates four different prolate spheroidal wave functions (PSWF), based on a source signal for use in ultra-wideband (UWB) communication systems is proposed, which is then applied to an M-ary communication system. This class of pulse shape yields orthogonal pulses that have a constant pulse width and bandwidth regardless of the pulse order, which

R. S. Dilmaghani; M. Ghavami; A. H. Aghvami

2004-01-01

38

An integrated 3.1-5.1 GHz pulse generator for ultra-wideband wireless localization systems  

NASA Astrophysics Data System (ADS)

This paper presents an implementation of an integrated Ultra-wideband (UWB), Binary-Phase Shift Keying (BPSK) Gaussian modulated pulse generator. VCO, multiplier and passive Gaussian filter are the key components. The VCO provides the carrier frequency of 4.1 GHz, the LC Gaussian filter is responsible for the pulse shaping in the baseband. Multiplying the baseband pulse and the VCO frequency shifts the pulse to the desired center frequency. The generated Gaussian pulse ocupppies the frequency range from 3.1 to 5.1 GHz with the center frequency at 4.1 GHz. Simulations and measured results show that this spectrum fulfills the mask for indoor communication systems given by the FCC (Federal Communications Commission, 2002). The total power consumption is 55 mW using a supply voltage of 2.5 V. Circuits are realized using the IHP 0.25 ?m SiGe:C BiCMOS technology.

Fan, X.; Fischer, G.; Dietrich, B.

2006-09-01

39

Penetration and propagation into biological matter and biological effects of high-power ultra-wideband pulses: a review.  

PubMed

Abstract Systems emitting ultra-wideband high power microwave (HP/UWB) pulses are developed for military and civilian applications. HP/UWB pulses typically have durations on the order of nanoseconds, rise times of picoseconds and amplitudes around 100?kV?m(-1). This article reviews current research on biological effects from HP/UWB exposure. The different references were classified according to endpoints (cardiovascular system, central nervous system, behavior, genotoxicity, teratology?…). The article also reviews the aspects of mechanisms of interactions and tissue damage as well as the numerical work that has been done for studying HP/UWB pulse propagation and pulse energy deposition inside biological tissues. The mechanisms proposed are the molecular conformation change, the modification of chemical reaction rates, membrane excitation and breakdown and direct electrical forces on cells or cell constituents, and the energy deposition. As regards the penetration of biological matter and the deposited energy, mainly computations were published. They have shown that the EM field inside the biological matter is strongly modified compared to the incident EM field and that the energy absorption for HP/UWB pulses occurs in the same way as for continuous waves. However, the energy carried by a HP/UWB pulse is very low and the deposited energy is low. The number of published studies dealing with the biological effects is small and only a few pointed out slight effects. It should be further noted that the animal populations used in the studies were not always large, the statistical analyses not always relevant and the teams involved in this research rather limited in number. PMID:25356665

Schunck, Thérèse; Bieth, François; Pinguet, Sylvain; Delmote, Philippe

2014-10-30

40

Multiple signal waveforms adaptation in cognitive ultra-wideband radio evolution  

Microsoft Academic Search

Cognitive ultra-wideband (UWB) radio is proposed to exploit the advantages and the unique features of enhancing UWB wireless technologies by utilizing cognitive radio functionality. In order to achieve the cognitive UWB radio, multiple pulse waveforms adaptation has been investigated for producing the expected spectral notches while matching with the Federal Communications Commission (FCC) spectral mask. Then the specifically designed pulse

Honggang Zhang; Xiaofei Zhou; Kamya Yekeh Yazdandoost; Imrich Chlamtac

2006-01-01

41

Photonic generation of background-free millimeter-wave ultra-wideband pulses based on a single dual-drive Mach-Zehnder modulator.  

PubMed

We propose a novel photonic approach for generating a background-free millimeter-wave (MMW) ultra-wideband (UWB) signal based on a conventional dual-drive Mach-Zehnder modulator (DMZM). One arm of the DMZM is driven by a local oscillator (LO) signal. The LO power is optimized to realize optical carrier suppressed modulation. The other arm is fed by a rectangular signal. The MMW UWB pulses are generated by truncating the continuous wave LO signal into a pulsed one in a photodetector (PD). The generated MMW UWB signal is background-free by eliminating the baseband frequency components because the optical power launched to the PD keeps constant all the time. The proposed method is theoretically analyzed and experimentally verified. The generated MMW UWB signal centered at a frequency of 26 GHz meets the Federal Communications Commission spectral mask very well. PMID:24690706

Li, Wei; Wang, Wen Ting; Sun, Wen Hui; Wang, Li Xian; Zhu, Ning Hua

2014-03-01

42

A platform for ultra wideband communication systems  

E-print Network

In this thesis, a web interface for sending and receiving data across an actual UWB channel was designed. In addition, a platform for Ultra Wideband (UWB) communication development was implemented. The UWB communication ...

Ackerman, Nathan (Nathan Joseph)

2005-01-01

43

Low-loss ultra-wideband (UWB) filters using suspended stripline  

Microsoft Academic Search

Two types of suspended stripline ultra-wideband bandpass filters are described, one based on a standard lumped element (L-C) filter concept including transmission zeroes to improve the upper passband slope, and a second one consisting of the combination of a low-pass and a high-pass filter.

Wolfgang Menzel; Mohammad S. Rahman Tito; Lei Zhu

2005-01-01

44

Ultra wideband surface wave communications  

NASA Astrophysics Data System (ADS)

Ultra Wideband (UWB), an impulse carrier waveform, was applied at HF-VHF frequencies to utilize surface wave propagation. UWB involves the propagation of transient pulses rather than continuous waves which makes the system easier to implement, inexpensive, low power and small. Commercial UWB for wireless personal area networks is 3.1 to 10.6 GHz band as approved by the FCC with ranges up to 12 ft. The use of surface wave propagation (instead of commercial SHF UWB) extends the communication range. Surface wave is a means of propagation where the wave is guided by the surface of the Earth. Surface wave is efficient at low frequencies, VLF to HF. The UWB HF channel was modeled and also experimentally characterized. The Federal Communications Commission (FCC) defines UWB as a signal with either a fractional bandwidth of 20% of the center frequency or a bandwidth of 500MHz. Designing an antenna to operate over the 20% bandwidth requirement of UWB is one of the greatest challenges. Two different antenna designs are presented, a spoke top antenna and a traveling wave antenna with photonic bandgap. These designs were implemented at the commercial UWB frequencies (3.1--10.6 GHz) due to availability of modeling tools for the higher frequencies, the reduced antenna size and the availability of measurement facilities. The spoke top was optimum for replication of the time domain input signal. The traveling wave antenna with photonic bandgap demonstrated increased impedance bandwidth of the antenna.

Lacomb, Julie Anne

45

Ultra-wideband radar motion sensor  

DOEpatents

A motion sensor is based on ultra-wideband (UWB) radar. UWB radar range is determined by a pulse-echo interval. For motion detection, the sensors operate by staring at a fixed range and then sensing any change in the averaged radar reflectivity at that range. A sampling gate is opened at a fixed delay after the emission of a transmit pulse. The resultant sampling gate output is averaged over repeated pulses. Changes in the averaged sampling gate output represent changes in the radar reflectivity at a particular range, and thus motion. 15 figs.

McEwan, T.E.

1994-11-01

46

Ultra-wideband radar motion sensor  

DOEpatents

A motion sensor is based on ultra-wideband (UWB) radar. UWB radar range is determined by a pulse-echo interval. For motion detection, the sensors operate by staring at a fixed range and then sensing any change in the averaged radar reflectivity at that range. A sampling gate is opened at a fixed delay after the emission of a transmit pulse. The resultant sampling gate output is averaged over repeated pulses. Changes in the averaged sampling gate output represent changes in the radar reflectivity at a particular range, and thus motion.

McEwan, Thomas E. (Livermore, CA)

1994-01-01

47

Through-the-wall localization of a moving target by two independent ultra wideband (UWB) radar systems.  

PubMed

In the case of through-the-wall localization of moving targets by ultra wideband (UWB) radars, there are applications in which handheld sensors equipped only with one transmitting and two receiving antennas are applied. Sometimes, the radar using such a small antenna array is not able to localize the target with the required accuracy. With a view to improve through-the-wall target localization, cooperative positioning based on a fusion of data retrieved from two independent radar systems can be used. In this paper, the novel method of the cooperative localization referred to as joining intersections of the ellipses is introduced. This method is based on a geometrical interpretation of target localization where the target position is estimated using a properly created cluster of the ellipse intersections representing potential positions of the target. The performance of the proposed method is compared with the direct calculation method and two alternative methods of cooperative localization using data obtained by measurements with the M-sequence UWB radars. The direct calculation method is applied for the target localization by particular radar systems. As alternative methods of cooperative localization, the arithmetic average of the target coordinates estimated by two single independent UWB radars and the Taylor series method is considered. PMID:24021968

Kocur, Dušan; Svecová, Mária; Rov?áková, Jana

2013-01-01

48

Through-the-Wall Localization of a Moving Target by Two Independent Ultra Wideband (UWB) Radar Systems  

PubMed Central

In the case of through-the-wall localization of moving targets by ultra wideband (UWB) radars, there are applications in which handheld sensors equipped only with one transmitting and two receiving antennas are applied. Sometimes, the radar using such a small antenna array is not able to localize the target with the required accuracy. With a view to improve through-the-wall target localization, cooperative positioning based on a fusion of data retrieved from two independent radar systems can be used. In this paper, the novel method of the cooperative localization referred to as joining intersections of the ellipses is introduced. This method is based on a geometrical interpretation of target localization where the target position is estimated using a properly created cluster of the ellipse intersections representing potential positions of the target. The performance of the proposed method is compared with the direct calculation method and two alternative methods of cooperative localization using data obtained by measurements with the M-sequence UWB radars. The direct calculation method is applied for the target localization by particular radar systems. As alternative methods of cooperative localization, the arithmetic average of the target coordinates estimated by two single independent UWB radars and the Taylor series method is considered. PMID:24021968

Kocur, Dušan; Švecová, Mária; Rov?áková, Jana

2013-01-01

49

FDTD analysis of a gigahertz TEM cell for ultra-wideband pulse exposure studies of biological specimens.  

PubMed

Gigahertz transverse electromagnetic (GTEM) transmission cells have been previously used to experimentally study exposure of biological cells to ultra-wideband (UWB), monopolar, electromagnetic pulses. Using finite-difference time-domain (FDTD) simulations we examine the time-dependent electric field waveforms and energy dose spatial distributions within a finite volume of biological cell culture medium during these experiments. The simulations show that when one or more flasks containing cell culture media are placed inside the GTEM cell, the uniform fields of the empty GTEM cell are significantly perturbed. The fields inside the cell culture medium, representing the fields to which the biological cells are exposed, are no longer monopolar and are spatially highly nonuniform. These effects result from a combination of refraction and distortion of the incident wave, combined with excitation of resonant eigenmodes within the cell culture medium volume. The simulations show that these distortions of the incident waveform may be mitigated by supporting the sample on a high permittivity pedestal and modifying the incident waveform to more closely approximate a Gaussian pulse. Under all simulated conditions, the estimated maximum temperature rises are completely negligible, ensuring that any experimentally observed unusual cell function or histopathology can be associated with nonthermal effects. PMID:16686400

Ji, Zhen; Hagness, Susan C; Booske, John H; Mathur, Satnam; Meltz, Martin L

2006-05-01

50

Ultra-wideband directional sampler  

DOEpatents

The Ultra-Wideband (UWB) Directional Sampler is a four port device that combines the function of a directional coupler with a high speed sampler. Two of the four ports operate at a high sub-nanosecond speed, in ``real time``, and the other two ports operate at a slow millisecond-speed, in ``equivalent time``. A signal flowing inbound to either of the high speed ports is sampled and coupled, in equivalent time, to the adjacent equivalent time port while being isolated from the opposite equivalent time port. A primary application is for a time domain reflectometry (TDR) situation where the reflected pulse returns while the outbound pulse is still being transmitted, such as when the reflecting discontinuity is very close to the TDR apparatus. 3 figs.

McEwan, T.E.

1996-05-14

51

Ultra-wideband directional sampler  

DOEpatents

The Ultra-Wideband (UWB) Directional Sampler is a four port device that combines the function of a directional coupler with a high speed sampler. Two of the four ports operate at a high sub-nanosecond speed, in "real time", and the other two ports operate at a slow millisecond-speed, in "equivalent time". A signal flowing inbound to either of the high speed ports is sampled and coupled, in equivalent time, to the adjacent equivalent time port while being isolated from the opposite equivalent time port. A primary application is for a time domain reflectometry (TDR) situation where the reflected pulse returns while the outbound pulse is still being transmitted, such as when the reflecting discontinuity is very close to the TDR apparatus.

McEwan, Thomas E. (Livermore, CA)

1996-01-01

52

Transmit Power Allocation among PSWF-based Pulse Wavelets in Cognitive UWB Radio  

Microsoft Academic Search

Ultra wideband (UWB) technology has been considered as one of the suitable transmission techniques for implementing a cognitive radio system, where spectrum-agile UWB waveforms achieve adaptation features. One approach for designing such waveforms relies on orthogonally combining PSWF-based pulse wavelets. In a cognitive UWB radio environment with N users, with respect to the case of one sub-band accessed by one

Xiaofei Zhou; Honggang Zhang; Imrich Chlamtac

2006-01-01

53

Antenna design for ultra wideband radio  

E-print Network

The recent allocation of the 3.1-10.6 GHz spectrum by the Federal Communications Commission (FCC) for Ultra Wideband (UWB) radio applications has presented a myriad of exciting opportunities and challenges for design in ...

Powell, Johnna, 1980-

2004-01-01

54

FCC compliant 3.1-10.6 GHz UWB Pulse Radar System using Correlation Detection  

Microsoft Academic Search

A short range 3.1-10.6 GHz single band ultra-wideband (UWB) pulse radar system is presented. The transmitter consists of a pulse generator that is connected to a broadband monopole antenna. The generated pulse shape is similar to the fifth derivative of the Gaussian bell shape and makes efficient use of the allocated FCC UWB frequency mask. The receiver is realized with

J. Dederer; B. Schleicher; F. De Andrade Tabarani Santos; A. Trasser; H. Schumacher

2007-01-01

55

CMOS implementation of ultra-wideband systems  

NASA Astrophysics Data System (ADS)

Ultra-Wideband systems is the collective term for wireless devices with a large spectral footprint and a low transmission power. The extreme low power spectral density of the UWB system forms a vast difference with classic communication systems that employ a large power within a small frequency band. Implementation approaches of Ultra-Wideband enclose classical carrier-based OFDM systems and pulse-based systems, each with their play trumps and disadvantages. Depending on the final application, cost, power or bandwidth can be the key target. Deep-submicron technologies allow to extend the limiting boundaries of analog building blocks but also introduce new challenges. Furthermore, new problems with respect to analog design deserve our attention: The high bandwidth of the signals involved in wideband systems obliges to migrate to a broadband receiver chain: LNA's (Low Noise Amplifier), mixers and ADC's with a wideband in- and output have to be designed, while commonly used techniques such as inductive peaking in the power amplifier cannot be used any more. Both advantages and disadvantages of OFDM and pulse-based transceiver architectures will be compared, together with simulation data, in order to give an overview of important design aspects of an Ultra-Wideband application.

Vereecken, Wim; Steyaert, Michiel

2005-06-01

56

Ultra-wideband source research  

Microsoft Academic Search

Ultra-wideband (UWB) microwave sources and antennas are of interest for a variety of applications such as transient radar, mine detection and unexploded ordnance (UXO) location and identification. Much of the current research is being performed at the Air Force Research Laboratory (AFRL) at Kirtland AFB, NM, USA. The approach to high power source development has included high pressure gas switching,

William D. Prather; Carl E. Baum; Jane M. Lehr; J. P. O'Loughlin; S. Tyo; J. S. H. Schoenberg; R. J. Torres; T. C. Tran; D. W. Scholfield; J. W. Burger; J. Gaudet

1999-01-01

57

Optimum Pulse Shape Design for UWB Systems with Timing Jitter  

NASA Astrophysics Data System (ADS)

This paper proposes a novel technique in designing the optimum pulse shape for ultra wideband (UWB) systems under the presence of timing jitter. In the UWB systems, pulse transmission power and timing jitter tolerance are crucial keys to communications success. While there is a strong desire to maximize both of them, one must be traded off against the other. In the literature, much effort has been devoted to separately optimize each of them without considering the drawback to the other. In this paper, both factors are jointly considered. The proposed pulse attains the adequate power to survive the noise floor and at the same time provides good resistance to the timing jitter. The proposed pulse also meets the power spectral mask restriction as prescribed by the Federal Communications Commission (FCC) for indoor UWB systems. Simulation results confirm the advantages of the proposed pulse over other previously known UWB pulses. Parameters of the proposed optimization algorithm are also investigated in this paper.

Lee, Wilaiporn; Kunaruttanapruk, Suwich; Jitapunkul, Somchai

58

Pulse Shape Modulation for UWB Communication: Performance with Channel Estimation Error  

Microsoft Academic Search

In this paper we consider M-ary biorthogonal pulse shape modulation (BPSM) scheme, for an impulse radio ultra wideband (IR-UWB) system transmitting over lognormal fading channels. The receiver has RAKE structure which combines the signal energy scattered over several resolvable multipath components via maximum ratio combiner (MRC) or eual gain combiner (EGC). We derive closed form expressions for symbol error probability,

Liangnan Wu; Azadeh Vosoughi

2009-01-01

59

Pulse shape modulation for UWB communication: Performance with channel estimation error  

Microsoft Academic Search

In this paper we consider M-ary biorthogonal pulse shape modulation (BPSM) scheme, for an impulse radio ultra wideband (IR-UWB) system transmitting over lognormal fading channels. The receiver has RAKE structure which combines the signal energy scattered over several resolvable multipath components via maximum ratio combiner (MRC) or eual gain combiner (EGC). We derive closed form expressions for symbol error probability,

Liangnan Wu; Azadeh Vosoughi

2008-01-01

60

Photonic generation of ultra-wideband monocycle and doublet pulses using simplex semiconductor optical amplifier  

NASA Astrophysics Data System (ADS)

We demonstrate two all-optical methods for UWB pulse generation based on various nonlinearities of the semiconductor optical amplifier (SOA), namely, self phase modulation (SPM), and cross gain modulation (XGM). In the first method, we present UWB doublet generation based on SPM. The monocycle pulse is generated from dark return-to-zero (RZ) signal, and then converted to doublet pulse by injecting an additional probe signal with the SMF transmission. For the first time to best of our knowledge, we report that the generated doublet pulses are transmitted over 5km SMF by proper dispersion compensation without distortion. Second, we present UWB doublet generation by XGM of two cascaded SOAs. The configuration of our all-optical methods is compact and simple.

Dong, Jianji; Zhang, Xinliang; Huang, Dexiu; Zhou, Enbo

2008-11-01

61

A UWB pulse generation based on a phase modulator and programmable filter  

NASA Astrophysics Data System (ADS)

A simple scheme for the ultra-wideband (UWB) pulse generation based on a phase modulator and programmable filter is proposed and experimentally demonstrated. By locating the center wavelength of two tunable lasers at left and right linear slope of the filter, polarity-reversed monocycle pluses are generated. A section of single mode fiber is utilized to introduce proper time delay between the pair of UWB monocycle pulses. By switching the programmable filter between bandpass filter and notch filter, positive and negative doublet pulse can be obtained additionally. The generated UWB pulses are measured in both time and frequency domain.

Yang, Chengliang; Xia, Li; Fu, Songnian; Liu, Deming

2014-05-01

62

Coupled-slotline-hybrid sampling mixer integrated with step-recovery-diode pulse generator for UWB applications  

Microsoft Academic Search

A new compact low-cost sampling mixer with internal local strobe-pulse generator for (carrierless) ultra-wideband (UWB) applications, especially for sub-sampling of UWB video pulse signals, is presented along with detailed design information. The sampler employs a double-sided planar structure to facilitate interface with the strobe-pulse generator and the baseband circuit without using wire connections or air bridges, enabling hybrid microwave integrated-circuit

Jeongwoo Han; Cam Nguyen

2005-01-01

63

Multi-pulse frequency shifted (MPFS) multiple access modulation for ultra wideband  

DOEpatents

The multi-pulse frequency shifted technique uses mutually orthogonal short duration pulses o transmit and receive information in a UWB multiuser communication system. The multiuser system uses the same pulse shape with different frequencies for the reference and data for each user. Different users have a different pulse shape (mutually orthogonal to each other) and different transmit and reference frequencies. At the receiver, the reference pulse is frequency shifted to match the data pulse and a correlation scheme followed by a hard decision block detects the data.

Nekoogar, Faranak (San Ramon, CA); Dowla, Farid U. (Castro Valley, CA)

2012-01-24

64

A novel ultra-wideband microstrip antenna  

Microsoft Academic Search

This paper describes the design of a novel ultra-wideband (UWB) antenna for UWB applications. The design is based on planar rectangular monopole microstrip antenna. The optimum antenna geometry is obtained by computation calculation, and the results were simulated by using electromagnetic simulation software CST MWS(CST microwave studio). The results show that the microstrip antenna can get in the range of

Xiaodong Deng; Xiaodong Yang; Bingcai Chen; Yu Bai

2011-01-01

65

Novel low-cost ultra-wideband, ultra-short-pulse transmitter with MESFET impulse-shaping circuitry for reduced distortion and improved pulse repetition rate  

Microsoft Academic Search

A new ultra-wideband, ultra-short-pulse transmitter has been developed using microstrip lines, step-recovery and Schottky diodes, MESFET, and monolithic microwave integrated circuit (MMIC) amplifier. This transmitter employs a novel MESFET impulse-shaping circuit to achieve several unique advantages, including less distortion, easy broadband matching, and increased pulse repetition rate. The transmitter produces 300-ps monocycle pulses with about 2 V peak-to-peak and a

Jeong Soo Lee; Cam Nguyen

2001-01-01

66

Ultra-wideband precision asset location system  

Microsoft Academic Search

A prototype ultra-wideband (UWB) precision asset location (PAL) system was developed and tested aboard the SS Curtiss in Port Hueneme, California. The PAL system was developed to assess the capability of UWB geolocation to operate in severe multipath shipboard environments. The PAL system was based on an earlier UWB relative-time-of-arrival (RTOA) transceiver location system and was extended to a differential-time-of-arrival

Robert J. Fontana; Steven J. Gunderson

2002-01-01

67

An UWB cognitive radio system based on bridge function sequence matrix and PSWF pulse waveform  

Microsoft Academic Search

An Ultra Wideband (UWB) cognitive radio system using soft-spectrum adaptation (SSA) scheme is discussed. In this paper, SSA scheme is based on Bridge function sequence square matrix and PSWF-based orthogonal pulse waveform. Every information bit is transmitted over parallel Bridge function sequence square matrix, each row of which is carried by a different PSWF-based orthogonal chip pulse waveform. Each row

Jinshan Di; Sheng Hong; Qishan Zhang; Ying Li; Hongsheng Zhao

2010-01-01

68

Photonic multi-shape UWB pulse generation using a semiconductor optical amplifier-based nonlinear optical loop mirror  

NASA Astrophysics Data System (ADS)

We propose and demonstrate a scheme to implement photonic multi-shape ultra-wideband (UWB) signal generation using a semiconductor optical amplifier (SOA) based nonlinear optical loop mirror (NOLM). By employing the cross phase modulation (XPM) effect, cross gain modulation (XGM), or both, multi-shape UWB waveforms are generated including monocycle, doublet, triplet, and quadruplet pulses. Both the shapes and polarities of the generated pulses are flexible to adjust, which may be very useful in UWB pulse shape modulation and pulse polarity modulation.

Luo, Bo-Wen; Dong, Jian-Ji; Yu, Yuan; Yang, Ting; Zhang, Xin-Liang

2013-02-01

69

High-Speed Photonic Power-Efficient Ultra-Wideband Transceiver Based on Multiple PM-IM Conversions  

Microsoft Academic Search

We experimentally demonstrate a novel photonic ultra-wideband (UWB) transceiver with pulse spectral efficiency of 50.97% and transmission speed up to 3.125 Gb\\/s. The UWB generator only consists of a highly nonlinear fiber (HNLF) and a commercial arrayed-waveguide grating (AWG). By using the concept of multiple cross-phase modulation in the HNLF and multiple phase modulation to intensity modulation conversions in the

Enbo Zhou; Xing Xu; King-Shan Lui; Kenneth Kin-Yip Wong

2010-01-01

70

Obstacle avoidance and concealed target detection using the Army Research Lab ultra-wideband synchronous impulse reconstruction (UWB SIRE) forward imaging radar  

NASA Astrophysics Data System (ADS)

The U.S. Army Research Laboratory (ARL), as part of a mission and customer funded exploratory program, has developed a new low-frequency, ultra-wideband (UWB) synthetic aperture radar (SAR) for forward imaging to support the Army's vision of an autonomous navigation system for robotic ground vehicles. These unmanned vehicles, equipped with an array of imaging sensors, will be tasked to help detect man-made obstacles such as concealed targets, enemy minefields, and booby traps, as well as other natural obstacles such as ditches, and bodies of water. The ability of UWB radar technology to help detect concealed objects has been documented in the past and could provide an important obstacle avoidance capability for autonomous navigation systems, which would improve the speed and maneuverability of these vehicles and consequently increase the survivability of the U. S. forces on the battlefield. One of the primary features of the radar is the ability to collect and process data at combat pace in an affordable, compact, and lightweight package. To achieve this, the radar is based on the synchronous impulse reconstruction (SIRE) technique where several relatively slow and inexpensive analog-to-digital (A/D) converters are used to sample the wide bandwidth of the radar signals. We conducted an experiment this winter at Aberdeen Proving Ground (APG) to support the phenomenological studies of the backscatter from positive and negative obstacles for autonomous robotic vehicle navigation, as well as the detection of concealed targets of interest to the Army. In this paper, we briefly describe the UWB SIRE radar and the test setup in the experiment. We will also describe the signal processing and the forward imaging techniques used in the experiment. Finally, we will present imagery of man-made obstacles such as barriers, concertina wires, and mines.

Nguyen, Lam; Wong, David; Ressler, Marc; Koenig, Francois; Stanton, Brian; Smith, Gregory; Sichina, Jeffrey; Kappra, Karl

2007-04-01

71

Ultra-wideband source and antenna research  

Microsoft Academic Search

Ultra-wideband (UWB) microwave sources and antennas are of interest for a variety of applications, such as transient radar, mine detection, and unexploded ordnance (UXO) location and identification. Much of the current research is being performed at the Air Force Research Laboratory (AFRL) at Kirtland AFB, NM. The approach to high power source development has included high pressure gas switching, oil

William D. Prather; Carl E. Baum; Jane M. Lehr; J. P. O'Loughlin; S. Tyo; J. S. H. Schoenberg; R. J. Torres; T. C. Tran; D. W. Scholfield; J. Gaudet; J. W. Burger

2000-01-01

72

Clear Channel Assessment in Ultra-Wideband Sensor Networks  

NASA Astrophysics Data System (ADS)

Impulse ultra-wideband (UWB) is an attractive technology for large ad hoc sensor networks due to its precise ranging capacity, multi-path fading robustness and low radiation power. The transient and carrier-less nature of low radiation pulse and harsh multipath channel condition makes it cumbersome to implement carrier sensing. We proposed clear channel assessment (CCA) based on preamble-assisted modulation (PAM) for UWB sensor networks. Preamble symbols are periodically inserted into the frame payload in the time domain to serve as regular feature for reliable CCA. We simulated the CCA performance in the multipath UWB channel model developed by IEEE 802.15.4a. PAM and CCA configurations were optimized for the distributed carrier sense multiple access protocol. PAM was accepted by 802.15.4a group as an optional feature. Furthermore, the multiplexed preamble symbols can be exploited for channel estimation to improve communication and ranging.

Zhen, Bin; Li, Huan-Bang; Kohno, Ryuji

73

Ultra-wideband signal propagation experiments in liquid media  

NASA Astrophysics Data System (ADS)

Ultra-wideband (UWB) signals exhibit different characteristics upon propagation through matter compared with narrowband signals. The latter keeping a sinusoidal shape during different forms of signal propagation. The behavior of narrowband signals does not apply to UWB signals in many cases. Presently, the possibilities for development of UWB signaling technology remain largely unexplored. Only a few applications have been developed due to strict regulations by the Federal Communications Commission (FCC). In this paper we describe a series of experiments that have been carried out to determine the behavior of UWB signals and their properties. A TEM horn antenna has been made for radiating UWB signals. Experiments on pulse propagation have been carried out including an application to detection of stationary metal objects. A high accuracy in detecting metal objects has been achieved. A procedure for propagating UWB signals through a liquid medium of given salt concentration has been demonstrated, providing a basis for studying UWB signal propagation in biological matter. A new pulsewidth definition was adopted which is suitable for UWB signal propagation.

Challa, Shravan; Mitra, Atindra; Selmic, Rastko; Simicevic, Neven

2008-04-01

74

Ultra-Wideband Angle-of-Arrival Tracking Systems  

NASA Technical Reports Server (NTRS)

Systems that measure the angles of arrival of ultra-wideband (UWB) radio signals and perform triangulation by use of those angles in order to locate the sources of those signals are undergoing development. These systems were originally intended for use in tracking UWB-transmitter-equipped astronauts and mobile robots on the surfaces of remote planets during early stages of exploration, before satellite-based navigation systems become operational. On Earth, these systems could be adapted to such uses as tracking UWB-transmitter-equipped firefighters inside buildings or in outdoor wildfire areas obscured by smoke. The same characteristics that have made UWB radio advantageous for fine resolution ranging, covert communication, and ground-penetrating radar applications in military and law-enforcement settings also contribute to its attractiveness for the present tracking applications. In particular, the waveform shape and the short duration of UWB pulses make it possible to attain the high temporal resolution (of the order of picoseconds) needed to measure angles of arrival with sufficient precision, and the low power spectral density of UWB pulses enables UWB radio communication systems to operate in proximity to other radio communication systems with little or no perceptible mutual interference.

Arndt, G. Dickey; Ngo, Phong H.; Phan, Chau T.; Gross, Julia; Ni, Jianjun; Dusl, John

2010-01-01

75

Remote Monitoring and Tracking of UF6 Cylinders Using Long-Range Passive Ultra-wideband (UWB) RFID Tags  

SciTech Connect

An IAEA Technical Meeting on Techniques for IAEA Verification of Enrichment Activities identified 'smart tags' as a technology that should be assessed for tracking and locating UF6 cylinders. Although there is vast commercial industry working on RFID systems, the vulnerabilities of commercial products are only beginning to emerge. Most of the commercially off-the-shelf (COTS) RFID systems operate in very narrow frequency bands, making them vulnerable to detection, jamming and tampering and also presenting difficulties when used around metals (i.e. UF6 cylinders). Commercial passive RFID tags have short range, while active RFID tags that provide long ranges have limited lifetimes. There are also some concerns with the introduction of strong (narrowband) radio frequency signals around radioactive and nuclear materials. Considering the shortcomings of commercial RFID systems, in their current form, they do not offer a promising solution for continuous monitoring and tracking of UF6 cylinders. In this paper, we identify the key challenges faced by commercial RFID systems for monitoring UF6 cylinders, and introduce an ultra-wideband approach for tag/reader communications that addresses most of the identified challenges for IAEA safeguards applications.

Nekoogar, F; Dowla, F

2007-06-06

76

Optimal Waveforms Design for Ultra-Wideband Impulse Radio Sensors  

PubMed Central

Ultra-wideband impulse radio (UWB-IR) sensors should comply entirely with the regulatory spectral limits for elegant coexistence. Under this premise, it is desirable for UWB pulses to improve frequency utilization to guarantee the transmission reliability. Meanwhile, orthogonal waveform division multiple-access (WDMA) is significant to mitigate mutual interferences in UWB sensor networks. Motivated by the considerations, we suggest in this paper a low complexity pulse forming technique, and its efficient implementation on DSP is investigated. The UWB pulse is derived preliminarily with the objective of minimizing the mean square error (MSE) between designed power spectrum density (PSD) and the emission mask. Subsequently, this pulse is iteratively modified until its PSD completely conforms to spectral constraints. The orthogonal restriction is then analyzed and different algorithms have been presented. Simulation demonstrates that our technique can produce UWB waveforms with frequency utilization far surpassing the other existing signals under arbitrary spectral mask conditions. Compared to other orthogonality design schemes, the designed pulses can maintain mutual orthogonality without any penalty on frequency utilization, and hence, are much superior in a WDMA network, especially with synchronization deviations. PMID:22163511

Li, Bin; Zhou, Zheng; Zou, Weixia; Li, Dejian; Zhao, Chong

2010-01-01

77

Optimal waveforms design for ultra-wideband impulse radio sensors.  

PubMed

Ultra-wideband impulse radio (UWB-IR) sensors should comply entirely with the regulatory spectral limits for elegant coexistence. Under this premise, it is desirable for UWB pulses to improve frequency utilization to guarantee the transmission reliability. Meanwhile, orthogonal waveform division multiple-access (WDMA) is significant to mitigate mutual interferences in UWB sensor networks. Motivated by the considerations, we suggest in this paper a low complexity pulse forming technique, and its efficient implementation on DSP is investigated. The UWB pulse is derived preliminarily with the objective of minimizing the mean square error (MSE) between designed power spectrum density (PSD) and the emission mask. Subsequently, this pulse is iteratively modified until its PSD completely conforms to spectral constraints. The orthogonal restriction is then analyzed and different algorithms have been presented. Simulation demonstrates that our technique can produce UWB waveforms with frequency utilization far surpassing the other existing signals under arbitrary spectral mask conditions. Compared to other orthogonality design schemes, the designed pulses can maintain mutual orthogonality without any penalty on frequency utilization, and hence, are much superior in a WDMA network, especially with synchronization deviations. PMID:22163511

Li, Bin; Zhou, Zheng; Zou, Weixia; Li, Dejian; Zhao, Chong

2010-01-01

78

Optical UWB pulse generator using an N tap microwave photonic filter and phase inversion adaptable to different pulse modulation formats.  

PubMed

We propose theoretically and demonstrate experimentally an optical architecture for flexible Ultra-Wideband pulse generation. It is based on an N-tap reconfigurable microwave photonic filter fed by a laser array by using phase inversion in a Mach-Zehnder modulator. Since a large number of positive and negative coefficients can be easily implemented, UWB pulses fitted to the FCC mask requirements can be generated. As an example, a four tap pulse generator is experimentally demonstrated which complies with the FCC regulation. The proposed pulse generator allows different pulse modulation formats since the amplitude, polarity and time delay of generated pulse is controlled. PMID:19333263

Bolea, Mario; Mora, José; Ortega, Beatriz; Capmany, José

2009-03-30

79

Performance of ultra-wideband time-shift-modulated signals in the indoor wireless impulse radio channel  

Microsoft Academic Search

Impulse radio (IR) is a spread spectrum (SS) wireless technique in which ultra-wideband (UWB) communication waveforms that consist of trains of time-shifted sub-nanosecond pulses are modulated to convey information exclusively in the relative time position of the pulses. We make an assessment of the performance of non-binary IR modulation in the presence of multipath with detection using a RAKE receiver

Fernando Ramirez-Mireles; M. Z. Win; R. A. Scholtz

1997-01-01

80

ULTRA WIDEBAND POWER DIVIDER USING TAPERED LINE  

Microsoft Academic Search

A power divider with ultra-wideband (UWB) performance has been designed. The quarter-wave transformer in the conventional Wilkinson power divider is replaced by an exponentially tapered microstrip line. Since the tapered line provides a consistent impedance transformation across all frequencies, very low amplitude ripple of 0.2dB peak-to-peak in the transmission coe-cient and superior input return loss better than 15dB are achieved

Chun Tong Chiang; Boon-Kuan Chung

2010-01-01

81

Photonic generation of power-efficient ultra-wideband waveforms using a single semiconductor optical amplifier  

NASA Astrophysics Data System (ADS)

A novel photonic generation of power-efficient ultra-wideband (UWB) pulse by combining two asymmetric monocycle pulses with inverted polarities is experimentally demonstrated. The principle lies in cross-phase modulation (XPM) in a single semiconductor optical amplifier (SOA) and phase modulation to intensity modulation conversions in an arrayed-waveguide grating (AWG). The Federal Communications Committee (FCC) compliant UWB pulse gains 24.3 dB and 20.8 dB improvements compared to positive and negative monocycle pulses after power attenuation to respect the FCC spectral mask, respectively. The generated power-efficient UWB with pulse duration of about 310 ps has potential to achieve high speed transmission and modulation without overlapping and distortion.

Dong, Jianji; Zhang, Yin; Yu, Yuan; Huang, Dexiu; Zhang, Xinliang

2011-01-01

82

Photonic generation of power-efficient ultra-wideband waveforms using a single semiconductor optical amplifier  

NASA Astrophysics Data System (ADS)

A novel photonic generation of power-efficient ultra-wideband (UWB) pulse by combining two asymmetric monocycle pulses with inverted polarities is experimentally demonstrated. The principle lies in cross-phase modulation (XPM) in a single semiconductor optical amplifier (SOA) and phase modulation to intensity modulation conversions in an arrayed-waveguide grating (AWG). The Federal Communications Committee (FCC) compliant UWB pulse gains 24.3 dB and 20.8 dB improvements compared to positive and negative monocycle pulses after power attenuation to respect the FCC spectral mask, respectively. The generated power-efficient UWB with pulse duration of about 310 ps has potential to achieve high speed transmission and modulation without overlapping and distortion.

Dong, Jianji; Zhang, Yin; Yu, Yuan; Huang, Dexiu; Zhang, Xinliang

2010-12-01

83

Ultra wideband technology for wireless sensor networks  

NASA Astrophysics Data System (ADS)

Wireless sensor networks (WSNs) have emerged as an important method for planetary surface exploration. To investigate the optimized wireless technology for WSNs, we summarized the key requirements of WSNs and justified ultra wideband (UWB) technology by comparing with other competitive wireless technologies. We also analyzed network topologies as well as physical and MAC layer designs of IEEE 802.15.4a standard, which adopted impulse radio UWB (IR-UWB) technology. Our analysis showed that IR-UWB-based 802.15.4a standard could enable robust communication, precise ranging, and heterogeneous networking for WSNs applications. The result of our present work implies that UWB-based WSNs can be applied to future planetary surface exploration.

Wang, Yue; Xiong, Weiming

2011-08-01

84

Design of a CPW-fed Ultra Wideband Crown Circular Fractal Antenna  

Microsoft Academic Search

A new ultra wideband antenna fed by coplanar waveguide (CPW) is presented in this paper. A fractal structure is constructed to obtain ultra wideband (UWB) performance. The parameters and characteristics of the antenna and the simulation results show that the 6:1 or more bandwidth is achieved with the second order iterative antenna structure

Min Ding; Ronghong Jin; Junping Geng; Qi Wu; Wei Wang

2006-01-01

85

Abstract--Design of a fully differential sixth order GHz range gm-C lowpass filter for DS-CDMA UWB (ultra wideband)  

E-print Network

(ultra wideband) transceivers is presented. The filter is composed of three identical cascaded biquad parameters are highly sensitive to process variations. Switched capacitor filter implementations are popular-amps with bandwidth in the range of tens of GHz. Transconductor capacitor (gm-C) filters are well suited

Ha, Dong S.

86

PSWF-based direct-sequence UWB transmission using orthogonal ternary code sets  

Microsoft Academic Search

An enhanced Ultra Wideband (UWB) signaling scheme employing PSWF (Prolate Spheroidal Wave Functions)- based orthogonal chip pulses and ternary complementary code sets is proposed for Direct-Sequence (DS) UWB systems. Every information bit of each user is modulated and transmitted over a set of parallel sequences of PSWF-based orthogonal chip pulses and are further assigned to a ternary complementary code set

Chihong Cho; Masao Nakagawa; Honggang Zhang; Zheng Zhou

2006-01-01

87

Multiband Orthogonal PSWF Pulses Used for Mary PPM Ultra-Wideband System  

Microsoft Academic Search

In this paper, we proposed a multiband orthogonal PSWF pulse set design method. The designed pulse set has a high spectrum utilization efficiency while meeting the FCC spectral mask without frequency shifting or additional filtering. Based on this, a Mary PPM modulation scheme using the orthogonal pulse set is developed. In this scheme each user is assigned a different orthogonal

Hou Wen-jun; Wang Hong-xing

2011-01-01

88

Photonic generation of ultra-wideband signals by direct current modulation on SOA section of an SOA-integrated SGDBR laser.  

PubMed

Photonic ultra-wideband (UWB) pulses are generated by direct current modulation of a semiconductor optical amplifier (SOA) section of an SOA-integrated sampled grating distributed Bragg reflector (SGDBR) laser. Modulation responses of the SOA section of the laser are first simulated with a microwave equivalent circuit model. Simulated results show a resonance behavior indicating the possibility to generate UWB signals with complex shapes in the time domain. The UWB pulse generation is then experimentally demonstrated for different selected wavelength channels with an SOA-integrated SGDBR laser. PMID:20389743

Lv, Hui; Yu, Yonglin; Shu, Tan; Huang, Dexiu; Jiang, Shan; Barry, Liam P

2010-03-29

89

Cross-layer functionality in ultra-wideband applications, The EUWB perspective  

Microsoft Academic Search

EUWB (Coexisting Short Range Radio by Advanced Ultra-Wideband Radio Technology, FP7-ICT-215669, www.euwb.eu) has been an industry-led initiative of twenty-one major industrial and excellent academic organizations from Europe and Israel targeting innovative improvement, adaptation, integration and application of short-range Ultra-Wideband Radio Technology (UWB-RT). EUWB will effectively leverage and significantly enhance the scientific knowledge base in the advanced UWB-RT and will provide

Christian KOCKS; Alexander VIESSMANN; Shangbo Wang; Ernest SCHEIBER; Dong Xu; Guido H. BRUCK; Peter JUNG; S. Zeisberg

2009-01-01

90

Time-domain imaging of radar targets using ultra-wideband or short pulse radars  

NASA Astrophysics Data System (ADS)

The development of viable short-pulse radar system has renewed the interest in time domain imaging performed directly in time-domain with temporally measured signal. Since the short-pulse response of a target provides significant information about the positions and strengths of scattering centers, and if observations are made over a wide range of aspect angle, one might create an image of the target using the short-pulse response information. In this thesis, we have developed and implemented a time-domain radar imaging technique based on a space-time magnetic field integral equation, using a sine modulated exponential pulse, and employing the inverse Radon transform. Images of various aircraft models were created from measured target responses over a wide band of frequencies and over the entire range of aspect angles. For the limited-view problem, two techniques have been proposed to process this practical situation. One of the approaches is the method of projections onto convex sets (POCS) which has been used in image processing for a long time. We extend this approach to radar imaging for the first time and show some useful results. Another approach which we have demonstrated is to process the available measured projections in order to generate an estimate of the full set of projections, an image which is called a sinogram. The goal of this approach is to recover the sinogram from the available measured data using linear prediction. Since the scattered field of a target can be written as a superposition of distinct specular reflection arising from scattering centers on the target, the position and strength of the scattering centers can be predicted using linear prediction with the change of the observation angle. Thus the missing data can be predicted before reconstructing the image. In the imaging of complex radar target, the PO approximation is used in the reconstruction algorithm. However, the PO approximation is inadequate for scattering problems of a complex shaped conducting object such as aircraft. At high frequency, edge diffractions, multiple reflections, creeping waves, and surface travelling waves may also be important scattering mechanisms. Additionally, the spectral and angular windows for data are usually restricted by practical constraints. Therefore the time domain image of a aircraft may be different from their geometrical shape. We have investigated time domain imaging of aircraft employing SMEP responses, and interpret the reconstructed image from a new approach, based on analysis of the scattering mechanisms and the back-projection algorithm utilized in image retrieval. The time-domain inverse scattering identity with the incorporation of Geometrical Theory of Diffraction (GTD) is derived and some interesting experimental results are provided.

Dai, Yingcheng

91

All-optical ultra-wideband doublet signal source based on the cross-gain modulation in a semiconductor optical amplifier  

NASA Astrophysics Data System (ADS)

We propose a novel scheme to generate the ultra-wideband (UWB) doublet signal pulse based on the cross-gain modulation (XGM) in a semiconductor optical amplifier (SOA). In the scheme, only an optical source and an SOA are needed. As there is only one wavelength included in the output doublet signal pulse, no time difference between the upper and down pulses is introduced during the transmission process. By using the software of Optisystem 7.0, the impacts of the optical power, the SOA current, the wavelength and the input signal pulse width on the generated doublet pulse are simulated and tudied numerically. The results show that when the pulse width of the input signal pulse is larger, the output signal pulse is better, and is insensitive to the change of wavelength. In addition, the ultra-wideband positive and negative monocycles can be generated by choosing suitable optical source power and SOA current.

Zhao, Zan-shan; Li, Pei-li; Zheng, Jia-jin; Pan, Ting-ting; Huang, Shi-jie; Luo, You-hong

2012-03-01

92

Evaluation of an Ultra-Wideband Propagation Channel  

Microsoft Academic Search

This paper describes the results of an ultra- wideband (UWB) propagation study in which arrays of propagation measurements were made. After a description of the propagation measurement technique, an approach to the spatial and temporal decomposition of an array of mea- surements into wavefronts impinging on the receiving array is presented. Based on am odification of the CLEAN algo- rithm,

J. M. Cramer; R. A. Scholtz; M. Z. Win

2002-01-01

93

Nonparametric UWB radar imaging algorithm for moving target using multi-static RPM approach  

Microsoft Academic Search

Ultra-wideband (UWB) pulse radar is promising technology for the imaging sensors of rescue robots operating in disaster scenarios, where optical sensors are not applicable be- cause of dusty air or strong backlighting. An UWB radar imaging algorithm for a target with arbitrary motion has already been proposed. That algorithm is based on a circular approximation of the target boundary, and

Ryo Yamaguchi; Shouhei Kidera; Tetsuo Kirimoto

2011-01-01

94

All-optical UWB doublet pulses generation by using a delay interferometer  

NASA Astrophysics Data System (ADS)

We demonstrated a simple scheme to generate ultra wideband (UWB) doublet pulses by inputting a dark return-to-zero (RZ) signal into a fiber delay interferometer (FDI). An 0.625-Gbit/s dark-RZ pulse train where the pulse width is 120 ps was inputted into a FDI where the free spectral range (FSR) is 0.16 nm (˜20 GHz, according time delay is ˜50 ps) and the extinction ratio (ER) is 9 dB, and the phase difference of the two fiber arms was changed and controlled by adjusting the operation temperature of the FDI, by do so, UWB doublet pulses were directly generated at an output port of the FDI. The system parameter effects on the output UWB pulses were discussed. Moreover, we also numerically demonstrated that the UWB quadruplet pulses can be generated in the same set by optimizing system parameters. This scheme has some distinct advantages including easy integration, convenient tuning, good stability, and so on. Presented method also accords with the general features in future applied UWB-Over-Fiber communication system, such as, single optical source input, simple configuration and passive device.

Wang, Fei; Xu, En-Ming

2013-06-01

95

Ultra-Wideband Low-Noise Amplifier  

NASA Astrophysics Data System (ADS)

Ultra-Wideband (UWB) Low-Noise Amplifier (LNA) is an essential part of the digital TV and UWB signal processor, but what makes it hard to design is the comprehensive consideration of bandwidth, noise and gain control performance. A new solution of high performance amplifier with low-noise, UWB and direct current (DC) is presented (Fig.1), which is composed of a precision pre-amplifier with AD797, a stepped gain controller with VCA810 and a digital potentiometer, an eight-order Bessel low-pass filter with LC network, a zero-drift corrector with the digital compensation method. The test results (Tab 1-3 & Fig.6) show that the gain of amplifier can be adjusted from 0 to 80 dB by step, the fluctuation of the pass band from DC to 10 MHz is less than 0.87 dB, stop-band attenuation reaches -42 dB/2fc, the equivalent input noise voltage is less than 7.2 ?Vrms. This design successfully solves some high challenging contradictions, such as ultra-wideband and low-noise, stop-band attenuation and pass-band fluctuation, precise gain control and DC zero-drift correction.

Lei, Kaizhuo; Su, Jiao; Shang, Jintao; Cui, Quanshun; Yang, Haibo

96

Ultra-wideband communication system prototype using orthogonal frequency coded SAW correlators.  

PubMed

This paper presents preliminary ultra-wideband (UWB) communication system results utilizing orthogonal frequency coded SAW correlators. Orthogonal frequency coding (OFC) and pseudo-noise (PN) coding provides a means for spread-spectrum UWB. The use of OFC spectrally spreads a PN sequence beyond that of CDMA; allowing for improved correlation gain. The transceiver approach is still very similar to that of the CDMA approach, but provides greater code diversity. Use of SAW correlators eliminates many of the costly components that are typically needed in the intermediate frequency (IF) section in the transmitter and receiver, and greatly reduces the signal processing requirements. Development and results of an experimental prototype system with center frequency of 250 MHz are presented. The prototype system is configured using modular RF components and benchtop pulse generator and frequency source. The SAW correlation filters used in the test setup were designed using 7 chip frequencies within the transducer. The fractional bandwidth of approximately 29% was implemented to exceed the defined UWB specification. Discussion of the filter design and results are presented and are compared with packaged device measurements. A prototype UWB system using OFC SAW correlators is demonstrated in wired and wireless configurations. OFC-coded SAW filters are used for generation of a transmitted spread-spectrum UWB and matched filter correlated reception. Autocorrelation and cross-correlation system outputs are compared. The results demonstrate the feasibility of UWB SAW correlators for use in UWB communication transceivers. PMID:23475929

Gallagher, Daniel R; Kozlovski, Nikolai Y; Malocha, Donald C

2013-03-01

97

An ultra-wideband transceiver for biotelemetry systems  

NASA Astrophysics Data System (ADS)

This paper introduces an Ultra-Wideband (UWB) transceiver for in-vivo biotelemetry applications, especially for wireless endoscope. A system modeling, simulation and design trade-off analysis for an UWB impulse radio transceiver is presented that incorporates the human body attenuation effect, the IEEE 802.14a indoor channel model, and channel noise to determine an optimum architecture for the given applications. Based on the system simulation using Matlab, the severe effect from the human body attenuation has been identified and a non-coherent Transmit Reference (TR) Transceiver architecture with differential Binary Phase Shift Keying (DBPSK) modulation was selected as the best option for a communication link in biotelemetry applications. The transceiver consists of an all-digital transmitter with H-bridge output stage type of Pulse Generator (PG), wideband inductorless resistive shunt feedback Low Noise Amplifier (LNA) with thermal noise canceling, Gilbert mixer, Integrator, decision detector and Variable Delay Controller (VDC). The performance characteristics of the PG, LNA and mixer are presented by the circuit simulation results using 0.18?m digital CMOS technology.

Kim, Chul; Lehmann, Torsten; Nooshabadi, Saeid

2007-12-01

98

Ultra-wideband radios for time-of-flight-ranging and network position estimation  

DOEpatents

This invention provides a novel high-accuracy indoor ranging device that uses ultra-wideband (UWB) RF pulsing with low-power and low-cost electronics. A unique of the present invention is that it exploits multiple measurements in time and space for very accurate ranging. The wideband radio signals utilized herein are particularly suited to ranging in harsh RF environments because they allow signal reconstruction in spite of multipath propagation distortion. Furthermore, the ranging and positioning techniques discussed herein directly address many of the known technical challenges encountered in UWB localization regarding synchronization and sampling. In the method developed, noisy, corrupted signals can be recovered by repeating range measurements across a channel, and the distance measurements are combined from many locations surrounding the target in a way that minimizes the range biases associated to indirect flight paths and through-wall propagation delays.

Hertzog, Claudia A. (Houston, TX); Dowla, Farid U. (Castro Valley, CA); Dallum, Gregory E. (Livermore, CA); Romero, Carlos E. (Livermore, CA)

2011-06-14

99

Repetitive, plasma switched, gigawatt, ultra-wideband impulse transmitter development  

SciTech Connect

Sandia National Laboratories has developed several repetitive, ultra-wideband (UWB), impulse transmitters to address impulse source, and to support experimental applications. The sources fall into two different classes, pulse peaking and pulse shorting. SNIPER (Sub-Nanosecond ImPulsE Radiator) is a source which uses an oil peaking switch to obtain a fast risetime (250-pS) pulse of 2-nS duration. The output voltage ranges between few tens of kilovolts to 250-kV. EMBL (EnantioMorphic Blumlein) is a similar device (presently under development) which uses a gas switch to short the falling portion of a 2-nS pulse to approximately 100-pS. To date, an output voltage of approximately 600-kV has been obtained (700-kV is the design goal). Depending upon the source, repetitive operation from single shot to 5-kHz (1-kHz nominal) has been obtained with excellent reliability and repeatability. Both sources are plasma switched impulse transmitters using a Hydrogen-thyratron based modulator, an oil-filled Blumlein (of two types), a peaking (or shorting) switch and a wideband TEM horn. Powers exceeding one-gigawatt are routinely generated. This technology appears to be extendable to at least 10-gigawatts. The frequency spectrum of the radiated pulse from these sources include the spectrum of 100-MHz to 3-GHz. The pulse is generated externally and then injected into the antenna. Due to the high powers involved and the need to radiate a broad spectrum of frequencies, Sandia has concentrated on TEM horn antennas. Several TEM horns have been built and used during this program. In those cases where higher gains are desired for the higher frequencies, TEM horn-fed dish antennas have been employed. A detailed overview of the UWB Transmitters along with measured radiated electric field strengths will be presented.

Clark, R.S.; Rinehart, L.F.; Buttram, M.T.; Aurand, J.F.; Lundstrom, J.M.; Patterson, P.E.; Roose, L.D.; Crowe, W.

1992-01-01

100

Repetitive, plasma switched, gigawatt, ultra-wideband impulse transmitter development  

SciTech Connect

Sandia National Laboratories has developed several repetitive, ultra-wideband (UWB), impulse transmitters to address impulse source, and to support experimental applications. The sources fall into two different classes, pulse peaking and pulse shorting. SNIPER (Sub-Nanosecond ImPulsE Radiator) is a source which uses an oil peaking switch to obtain a fast risetime (250-pS) pulse of 2-nS duration. The output voltage ranges between few tens of kilovolts to 250-kV. EMBL (EnantioMorphic Blumlein) is a similar device (presently under development) which uses a gas switch to short the falling portion of a 2-nS pulse to approximately 100-pS. To date, an output voltage of approximately 600-kV has been obtained (700-kV is the design goal). Depending upon the source, repetitive operation from single shot to 5-kHz (1-kHz nominal) has been obtained with excellent reliability and repeatability. Both sources are plasma switched impulse transmitters using a Hydrogen-thyratron based modulator, an oil-filled Blumlein (of two types), a peaking (or shorting) switch and a wideband TEM horn. Powers exceeding one-gigawatt are routinely generated. This technology appears to be extendable to at least 10-gigawatts. The frequency spectrum of the radiated pulse from these sources include the spectrum of 100-MHz to 3-GHz. The pulse is generated externally and then injected into the antenna. Due to the high powers involved and the need to radiate a broad spectrum of frequencies, Sandia has concentrated on TEM horn antennas. Several TEM horns have been built and used during this program. In those cases where higher gains are desired for the higher frequencies, TEM horn-fed dish antennas have been employed. A detailed overview of the UWB Transmitters along with measured radiated electric field strengths will be presented.

Clark, R.S.; Rinehart, L.F.; Buttram, M.T.; Aurand, J.F.; Lundstrom, J.M.; Patterson, P.E.; Roose, L.D.; Crowe, W.

1992-09-01

101

Receiver improvement for ultra-wideband transmitted-reference systems  

Microsoft Academic Search

The optimality of the cross-correlation receiver for ultra-wideband (UWB) transmitted-reference (TR) systems is first justified as the optimal linear combiner with a noisy reference. In light of the observation that combining all the available paths with a noisy reference may lead to inferior performance to that of combining just some of them, a weighted cross-correlation receiver is proposed based on

Meng-Hsuan Chung; Robert A. Scholtz

2005-01-01

102

Generation of an ultra-wideband triplet signal based on semiconductor optical amplifier  

NASA Astrophysics Data System (ADS)

We propose a novel ultra-wideband (UWB) triplet signal source based on the cross-gain modulation (XGM) in semiconductor optical amplifier (SOA). In the proposed scheme, only an optical source and two SOAs are needed, so the all-optical structure is compact. A triplet optical pulse with center frequency of 6.25 GHz and fractional bandwidth of 83% is obtained by the scheme. The extinction ratio can be improved by the counter-propagating scheme. The triplet pulse signal with only one wavelength can be easily controlled, and can aviod the dispersion effect. The output triplet pulse signal is insensitive to the light wavelength shifts, its available wavelength range is wide, the dynamic range of the input power is more than 6 dBm, and the bias current of the SOAs is exhibited.

Ma, Qiang; Li, Pei-li; Zheng, Jia-jin; Shen, Dan-hong; Zhao, Meng; Zhou, Wen; Zhao, Zan-shan

2013-05-01

103

IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 54, NO. 5, MAY 2006 2169 A Computational Study of Ultra-Wideband Versus  

E-print Network

Study of Ultra-Wideband Versus Narrowband Microwave Hyperthermia for Breast Cancer Treatment Mark (NB) microwave hyperthermia for breast cancer treatment with a recently proposed ultra-wideband (UWB studies have shown local hyperthermia to be effective in the treatment of a variety of cancers [1

Hagness, Susan C.

104

Analysis on IR/TR-UWB Interference against Narrowband Systems  

NASA Astrophysics Data System (ADS)

This paper presents the analysis of in-band interference caused by pulse-based ultra-wideband (UWB) systems. The analysis contains both plain Impulse Radio UWB (IR-UWB) and Transmitted Reference UWB (TR-UWB) systems as a source of interference. The supposed victim is a narrowband BPSK system with a band-pass filter. The effect of pulse-based UWB systems is analyzed in terms of bit error rate. The analysis is given in terms of the specific combinations of pulse repetition frequency and center frequency of the narrowband bandpass filter. In those situations, the UWB interference cannot be modeled as a Gaussian noise. It also manifests situations in which the victim is under the severest or the slightest interference from TR-UWB. According to its result, the analysis is validated via simulation.

Shimizu, Yuki; Sanada, Yukitoshi

105

Ultra-wideband digital baseband  

E-print Network

The FCC approved the use of Ultra-wideband signals for communication purposes in February 2002 in the band from 3.1GHz to 10.6GHz, effectively opening 7.5GHz of free unlicensed bandwidth. There are two main constraints for ...

Blázquez-Fernández, Raúl, 1975-

2006-01-01

106

On Equalization for Direct Sequence-Ultra Wideband System Using Received Response Code Sequence  

NASA Astrophysics Data System (ADS)

This paper proposes a combination of novel Received Response (RR) sequence at the transmitter and Matched Filter-Equalizer-RAKE (MF-EQZ-RAKE) combining scheme receiver system for Direct Sequence-Ultra Wideband (DS-UWB) multipath channel model. When binary code sequence such as M sequence is used, there is a possibility of generating extra Inter-Symbol Interference (ISI) in the UWB system. Therefore, it is quite a challenging task to collect the energy efficiently although RAKE reception method is applied at the receiver. The main purpose of the proposed system is to overcome the performance degradation for UWB transmission due to the occurrence of Inter-Symbol Interference (ISI) during high speed transmission of ultra short pulses in a multipath channel. The proposed system improves the system performance by improving the RAKE reception performance using RR sequence and suppressing the ISI effect with the equalizer. Simulation results verify that significant improvement can be obtained by the proposed system especially in UWB multipath channel models such as channel CM4 that suffered severe ISI effect.

Toh, Keat Beng; Tachikawa, Shin'ichi

107

Ultra-wideband noise radar based on optical waveform generation  

NASA Astrophysics Data System (ADS)

A microwave-photonic, ultra-wideband (UWB) noise radar system is proposed and demonstrated. The system brings together photonic generation of UWB waveforms and fiber-optic distribution. The use of UWB noise provides high ranging resolution and better immunity to interception and jamming. Distribution over fibers allows for the separation the radar-operating personnel and equipment from the location of the front-end. The noise waveforms are generated using the amplified spontaneous emission that is associated with stimulated Brillouin scattering in a standard optical fiber, or with an erbium-doped fiber amplifier. Our experiments demonstrate a proof of concept for an integrated radar system, driven by optically generated UWB noise waveforms of more than 1 GHz bandwidth that are distributed over 10 km distance. The detection of concealed metallic object and the resolving of two targets with the anticipated ranging resolution are reported.

Grodensky, Daniel; Kravitz, Daniel; Zadok, Avi

2012-06-01

108

Detection of transformer winding radial deformations by using UWB pulses and DWT  

Microsoft Academic Search

The on-line monitoring of transformer winding radial deformations using Ultra-Wideband (UWB) sensors and Discrete Wavelet Transform (DWT) has been presented in this paper. The measurements on a simplified model of the transformer winding demonstrate the high sensitivity of the proposed method to detect the winding radial deformation.

Javad Ebrahimi; Gevorg B. Gharehpetian; Hamidreza Amindavar; Maryam A. Hejazi

2010-01-01

109

A compact LTCC ultra-wideband bandpass filter using semi-lumped parallel-resonance circuits for spurious suppression  

Microsoft Academic Search

A very compact ultra-wideband (UWB) bandpass filter with both high selectivity and suppressed spurious passband is implemented in the low-temperature co-fired ceramic (LTCC) substrate. By using the optimum distributed highpass filter structure of 11th-order, an ultra-wideband filter with the bandwidth from 3.1 GHz to 10.6 GHz is realized. In this study, the semi-lumped parallel resonance circuits are adopted in conjunction

Chung-Hwa Wu; Yo-Shen Lin; Chi-Hsueh Wang; Chun Hsiung Chen

2007-01-01

110

A survey of antennas for ultra-wideband applications  

NASA Astrophysics Data System (ADS)

The usage of ultra-wideband (UWB) technology is growing in many communication systems such as radar systems, communication and measurement systems and imaging systems mainly because unlike the other wireless technologies UWB is not restricted to using a narrow waveband and it has high speed data rate. The large transmission bandwidth makes UWB-based electronic device resistive to interferences and gives immunity against getting detected. Typical operational frequency range of the UWB devices varies from few 100s MHz to 10 GHz. However, the most popular UWB devices are designed to operate between 1-3 GHz. This paper presents an overview of different types of commercially available antennas suitable for UWB applications. The paper begins with the basics of understanding of antennas properties. Next, it discusses the main antenna characteristics like: radiation pattern (directional or omni-directional), gain, bandwidth, size, etc for different UWB applications and explains criterions for quantitative and qualitative performance measure of the antennas. The antennas covered in this paper include: TEM Horn, Folded horn, Dipole, Planner Fat Dipole, Cross Dipole, Rolled Dipole, UWB dielectric, Bowtie, Wire Bowtie, etc. This paper describes the pros and cons of each antenna and highlights the application areas of each antenna. Lastly, this paper summaries the important characteristics of the antennas and presents several promising directions for future enhancement of UWB antenna systems.

Sarfaraz, Maysam; Shirkhodaie, Amir

2008-04-01

111

UWB dual burst transmit driver  

DOEpatents

A dual burst transmitter for ultra-wideband (UWB) communication systems generates a pair of precisely spaced RF bursts from a single trigger event. An input trigger pulse produces two oscillator trigger pulses, an initial pulse and a delayed pulse, in a dual trigger generator. The two oscillator trigger pulses drive a gated RF burst (power output) oscillator. A bias driver circuit gates the RF output oscillator on and off and sets the RF burst packet width. The bias driver also level shifts the drive signal to the level that is required for the RF output device.

Dallum, Gregory E. (Livermore, CA); Pratt, Garth C. (Discovery Bay, CA); Haugen, Peter C. (Livermore, CA); Zumstein, James M. (Livermore, CA); Vigars, Mark L. (Livermore, CA); Romero, Carlos E. (Livermore, CA)

2012-04-17

112

INTRODUCTION TO ULTRA-WIDEBAND ANTENNAS Hans Gregory Schantz (h.schantz@ieee.org)  

E-print Network

INTRODUCTION TO ULTRA-WIDEBAND ANTENNAS Hans Gregory Schantz (h.schantz@ieee.org) Next-RF, Inc. 4811Cove Creek Drive Brownsboro, AL 35741 In addition, a UWB antenna is preferentially non- dispersive- periodic antenna is an example of a dispersive antenna. Larger scale components radiate low frequency

Arslan, Hüseyin

113

An ultra-wideband radar for vehicle detection in railroad crossings  

Microsoft Academic Search

This paper describes an ultra-wideband (UWB) radar system designed to detect motor vehicles such as cars and trucks when they are present in a railway crossing. Once fully developed, the detection performance of the system is to be compared against a video detection system in a test at a crossing in Maywood, Illinois. If the test is successful this system

Stephen P. Lohmeier; R. Rajaraman; V. C. Ramasami

2002-01-01

114

A Comparison of Ultra Wideband Signal Functions for Wireless Ad Hoc Networks  

Microsoft Academic Search

This paper describes, simulates, evaluates and compares four time and band limited functions that can be used to create ultra wideband signals. Expressions and methods for generating the functions are presented followed with simulations using uniform sets of parameters. It is shown at the -10bB points the Hermite, prolate spheroidal wave function (PSWF) and wavelets have suitable UWB properties. Using

Johnson I. Agbinya; Ha Dang Truong

2005-01-01

115

Photonic generation of power-efficient FCC-compliant ultra-wideband waveforms using semiconductor optical amplifier (SOA): theoretical analysis and experiment verification  

NASA Astrophysics Data System (ADS)

We theoretically design a power-efficient ultra-wideband pulse generator by combining three monocycle pulses with different weights. We also experimentally demonstrate a feasible scheme to generate such power-efficient ultra-wideband waveforms using cross-phase modulation in a single semiconductor optical amplifier. The designed ultra-wideband pulse fully satisfies the requirements for the spectral mask specified by the Federal Communications Commission with high power efficiency. In the experiment, a power-efficient ultra-wideband waveform with a pulse duration of 310 ps is achieved, and the power efficiency is greatly improved compared with that of a single monocycle pulse or a mixture of two monocycles.

Dong, Jian-Ji; Luo, Bo-Wen; Huang, De-Xiu; Zhang, Xin-Liang

2012-04-01

116

Performance analysis of multi-user UWB wireless communication systems  

Microsoft Academic Search

This paper presents a performance comparison of impulse radio ultra wideband (IR-UWB) and multi-band orthogonal frequency division multiplexing (MB-OFDM) for multi-user wireless communication systems. Focusing on the analysis of system performance affected by multi-user interference (MUI) over general additive white Gaussion noise (AWGN) channel, we run a complete system simulation for direct sequence pulse amplitude modulation (DS-PAM), time hopping pulse

Yuhong Li; Youzheng Wang; Jianhua Lu

2009-01-01

117

An overview of Sandia National Laboratories` plasma switched, gigawatt, ultra-wideband impulse transmitter program  

SciTech Connect

Sandia National Laboratories has developed several repetitive, ultra-wideband (UWB), impulse transmitters to address impulse source technology and to support experimental applications. The sources fall into two different classes, pulse peaking and pulse shorting depending on how the UWB frequency components are generated. ne frequency spectrum of the radiated pulse from these sources include the spectrum of 100-MHz to 3-GHz. Depending upon the source, repetitive operation from single shot to 5-kHz (1-kHz nominal) has been obtained with excellent reliability and repeatability. SNIPER (Sub-Nanosecond impulse Radiator) is a source which uses an oil peaking switch to obtain a fast risetime (250-pS) pulse of 2-nS duration. The output voltage ranges between few tens of kilovolts to 250-kV. EMBL (EnantioMorphic Blumlein) is a similar device (presently under development) which uses a gas switch to sharpen the trailing edge of a 2-nS pulse to approximately 100-pS. To date, an output voltage of approximately 600-kV has been obtained (700- kV is the design goal). Since the frequency spectra are identical between sources with sharpened leading or trailing edges, alternatively, one can use parallel switches to short the pulse at its peak voltage. The pulse is generated externally and then injected into the antenna. Due to the high powers involved and the need to radiate a broad spectrum of frequencies, Sandia has concentrated on TEM horn. antennas with special high voltage feed adapters. Several TEM horns have been built and used during this program. In those cases where higher gains are desired for the higher frequencies, TEM horn-fed, dish antennas have been employed. An overview of the UWB transmitters, including design and operation of the modulators, the PFN`S, the pulse sharpening switches and the antennas will be presented.

Clark, R.S.; Rinehart, L.F.; Buttram, M.T.; Aurand, J.F.

1992-11-01

118

An overview of Sandia National Laboratories' plasma switched, gigawatt, ultra-wideband impulse transmitter program  

SciTech Connect

Sandia National Laboratories has developed several repetitive, ultra-wideband (UWB), impulse transmitters to address impulse source technology and to support experimental applications. The sources fall into two different classes, pulse peaking and pulse shorting depending on how the UWB frequency components are generated. ne frequency spectrum of the radiated pulse from these sources include the spectrum of 100-MHz to 3-GHz. Depending upon the source, repetitive operation from single shot to 5-kHz (1-kHz nominal) has been obtained with excellent reliability and repeatability. SNIPER (Sub-Nanosecond impulse Radiator) is a source which uses an oil peaking switch to obtain a fast risetime (250-pS) pulse of 2-nS duration. The output voltage ranges between few tens of kilovolts to 250-kV. EMBL (EnantioMorphic Blumlein) is a similar device (presently under development) which uses a gas switch to sharpen the trailing edge of a 2-nS pulse to approximately 100-pS. To date, an output voltage of approximately 600-kV has been obtained (700- kV is the design goal). Since the frequency spectra are identical between sources with sharpened leading or trailing edges, alternatively, one can use parallel switches to short the pulse at its peak voltage. The pulse is generated externally and then injected into the antenna. Due to the high powers involved and the need to radiate a broad spectrum of frequencies, Sandia has concentrated on TEM horn. antennas with special high voltage feed adapters. Several TEM horns have been built and used during this program. In those cases where higher gains are desired for the higher frequencies, TEM horn-fed, dish antennas have been employed. An overview of the UWB transmitters, including design and operation of the modulators, the PFN'S, the pulse sharpening switches and the antennas will be presented.

Clark, R.S.; Rinehart, L.F.; Buttram, M.T.; Aurand, J.F.

1992-01-01

119

An overview of Sandia National Laboratories' plasma switched, gigawatt, ultra-wideband impulse transmitter program  

NASA Astrophysics Data System (ADS)

Sandia National Laboratories has developed several repetitive, ultra-wideband (UWB), impulse transmitters to address impulse source technology and to support experimental applications. The sources fall into two different classes, pulse peaking and pulse shorting depending on how the UWB frequency components are generated. The frequency spectrum of the radiated pulse from these sources include the spectrum of 100-MHz to 3-GHz. Depending upon the source, repetitive operation from single shot to 5-kHz (1-kHz nominal) has been obtained with excellent reliability and repeatability. SNIPER (Sub-Nanosecond Impulse Radiator) is a source which uses an oil peaking switch to obtain a fast risetime (250-pS) pulse of 2-nS duration. The output voltage ranges between few tens of kilovolts to 250-kV. EMBL (EnantioMorphic Blumlein) is a similar device (presently under development) which uses a gas switch to sharpen the trailing edge of a 2-nS pulse to approximately 100-pS. To date, an output voltage of approximately 600-kV has been obtained (700-kV is the design goal). Since the frequency spectra are identical between sources with sharpened leading or trailing edges, alternatively, one can use parallel switches to short the pulse at its peak voltage. The pulse is generated externally and then injected into the antenna. Due to the high powers involved and the need to radiate a broad spectrum of frequencies, Sandia has concentrated on TEM horn antennas with special high voltage feed adapters. Several TEM horns have been built and used during this program. In those cases where higher gains are desired for the higher frequencies, TEM horn-fed, dish antennas have been employed. An overview of the UWB transmitters, including design and operation of the modulators, the PFN'S, the pulse sharpening switches and the antennas will be presented.

Clark, R. S.; Rinehart, L. F.; Buttram, M. T.; Aurand, J. F.

120

Three-dimensional confocal imaging for breast cancer detection using CMOS Gaussian monocycle pulse transmitter and 4 × 4 ultra wideband antenna array with impedance matching layer  

NASA Astrophysics Data System (ADS)

A time-domain reflectometry breast cancer detection system was developed, which was composed of a Gaussian monocycle pulse (GMP) transmitter circuit fabricated by complementary metal oxide semiconductor (CMOS) 65 nm technology and an ultra wide-band (UWB) planar slot antenna array. The center frequency and bandwidth of the antenna were 6 and 9.2 GHz, respectively. The GMP train having the pulse width of 160 ps was generated by the 65 nm CMOS logic circuit with a core area of 0.0017 mm2 and was emitted by the 4 × 4 planar slot antenna array. The fabricated planar 4 × 4 antenna array with the matching layer could resolve the two separate 5 × 5 × 5 mm3 breast tumor phantoms, which were located at the depth of 22 mm with the spacing of 8 mm.

Sugitani, Takumi; Kubota, Shinichi; Hafiz, Mohiuddin; Xiao, Xia; Kikkawa, Takamaro

2014-01-01

121

Induced Mitogenic Activity in AML-12 Mouse Hepatocytes Exposed to Low-dose Ultra-Wideband Electromagnetic Radiation  

PubMed Central

Ultra–wideband (UWB) technology has increased with the use of various civilian and military applications. In the present study, we hypothesized that low-dose UWB electromagnetic radiation (UWBR) could elicit a mitogenic effect in AML-12 mouse hepatocytes, in vitro. To test this hypothesis, we exposed AML-12 mouse hepatocytes, to UWBR in a specially constructed gigahertz transverse electromagnetic mode (GTEM) cell. Cells were exposed to UWBR for 2 h at a temperature of 23°C, a pulse width of 10 ns, a repetition rate of 1 kHz, and field strength of 5–20 kV/m. UWB pulses were triggered by an external pulse generator for UWBR exposure but were not triggered for the sham exposure. We performed an MTT Assay to assess cell viability for UWBR-treated and sham-exposed hepatocytes. Data from viability studies indicated a time-related increase in hepatocytes at time intervals from 8–24 h post exposure. UWBR exerted a statistically significant (p < 0.05) dose-dependent response in cell viability in both serum-treated and serum free medium (SFM) -treated hepatocytes. Western blot analysis of hepatocyte lysates demonstrated that cyclin A protein was induced in hepatocytes, suggesting that increased MTT activity after UWBR exposure was due to cell proliferation. This study indicates that UWBR has a mitogenic effect on AML-12 mouse hepatocytes and implicates a possible role for UWBR in hepatocarcinoma. PMID:16705798

Dorsey, W. C.; Ford, B. D.; Roane, L.; Haynie, D. T.; Tchounwou, P. B.

2005-01-01

122

A localization and tracking application for UWB  

Microsoft Academic Search

An increasing demand for applications in the area of Ultra-Wideband Radio Technology led to the EUWB (Coexisting Short Range Radio by Advanced Ultra-Wideband Radio Technology, FP7-ICT-215669, www.euwb.eu) project, which has been started in April 2008. The goal of this industry-led initiative of major industrial and excellent academic organizations is the improvement, integration, and the applications of UltraWideband Radio Technology (UWB-RT).

Christian KOCKS; Ernest SCHEIBER; Dong Xu; Alexander VIESSMANN; Shangbo Wang; Guido H. BRUCK; Peter JUNG

2009-01-01

123

Orthogonal frequency coded filters for use in ultra-wideband communication systems.  

PubMed

The use of ultra-short pulses, producing very wide bandwidths and low spectral power density, are the widely accepted approach for ultra-wideband (UWB) communication systems. This approach is simple and can be implemented with current digital signal processing technologies. However, surface acoustic wave (SAW) devices have the capability of producing complex signals with wide bandwidths and relatively high frequency operation. This approach, using SAW based correlators, eliminates many of the costly components that are needed in the IF block in the transmitter and receiver, and reduces many of the signal processing requirements. This work presents the development of SAW correlators using orthogonal frequency coding (OFC) for use in UWB spread spectrum communication systems. OFC and pseudonoise (PN) coding provide a means for UWB spreading of data. The use of OFC spectrally spreads a PN sequence beyond that of code division multiple access (CDMA) because of the increased bandwidth providing an improvement in processing gain. The transceiver approach is still very similar to that of a CDMA but provides greater code diversity. Experimental results of a SAW filter designed with OFC transducers are presented. The SAW correlation filter was designed using seven contiguous chip frequencies within the transducer. SAW correlators with a 29% fractional bandwidth were fabricated on lithium niobate (LiNbO3) having a center frequency of 250 MHz. A coupling-of-modes (COM) model is used to predict the SAW filter response experimentally and is compared to the measured data. Good correlation between the predicted COM responses and the measured device data is obtained. Discussion of the design, analysis, and measurements are presented. The experimental matched filter results are shown for the OFC device and are compared to the ideal correlation. The results demonstrate the OFC SAW device concept for UWB communication transceivers. PMID:18407859

Gallagher, Daniel R; Malocha, Donald C; Puccio, Derek; Saldanha, Nancy

2008-03-01

124

Analysis of a multi-access scheme and asynchronous transmit-only UWB for wireless body area networks.  

PubMed

Ultra Wideband (UWB) has many favorable factors for use in a wireless body area network application. The major drawback is the high power consumption of an UWB receiver. One solution to address this problem is to use a transmit-only UWB sensor node. In this paper, we propose a multi-access scheme that is suitable for asynchronous transmit-only UWB wireless body area networks (UWB-WBAN). Each sensor attached on the patient under monitoring is assigned a unique number of UWB pulses per data bit. The number of UWB pulses assigned to the sensors is optimized to improve the bit error rate and system reliability. Simulation shows that through careful selection of the number of pulses for the sensors, it is possible to maintain almost similar bit error probability, regardless of the distance from the receiver. PMID:19964453

Keong, Ho Chee; Yuce, Mehmet R

2009-01-01

125

Multi-band OFDM UWB receiver with narrowband interference suppression  

E-print Network

A multi band orthogonal frequency division multiplexing (MB-OFDM) compatible ultra wideband (UWB) receiver with narrowband interference (NBI) suppression capability is presented. The average transmit power of UWB system is limited to -41.3 dBm/MHz...

Kelleci, Burak

2009-05-15

126

Ultra Wideband InterferenceUltra Wideband Interference Effects on an AmateurEffects on an Amateur  

E-print Network

Ultra Wideband InterferenceUltra Wideband Interference Effects on an AmateurEffects on an Amateur is the ARRL?What is the ARRL? Amateur radio hobbyists and publicAmateur radio hobbyists and public serviceSensitivity is important 1. http://www.arrl.org #12;Amateur Radio BandsAmateur Radio Bands MHz GHz Mid-Range Imaging Indoor

Southern California, University of

127

Ultra-wideband impedance sensor  

DOEpatents

The ultra-wideband impedance sensor (UWBZ sensor, or Z-sensor) is implemented in differential and single-ended configurations. The differential UWBZ sensor employs a sub-nanosecond impulse to determine the balance of an impedance bridge. The bridge is configured as a differential sample-and-hold circuit that has a reference impedance side and an unknown impedance side. The unknown impedance side includes a short transmission line whose impedance is a function of the near proximity of objects. The single-ended UWBZ sensor eliminates the reference side of the bridge and is formed of a sample and hold circuit having a transmission line whose impedance is a function of the near proximity of objects. The sensing range of the transmission line is bounded by the two-way travel time of the impulse, thereby eliminating spurious Doppler modes from large distant objects that would occur in a microwave CW impedance bridge. Thus, the UWBZ sensor is a range-gated proximity sensor. The Z-sensor senses the near proximity of various materials such as metal, plastic, wood, petroleum products, and living tissue. It is much like a capacitance sensor, yet it is impervious to moisture. One broad application area is the general replacement of magnetic sensors, particularly where nonferrous materials need to be sensed. Another broad application area is sensing full/empty levels in tanks, vats and silos, e.g., a full/empty switch in water or petroleum tanks. 2 figs.

McEwan, T.E.

1999-03-16

128

Ultra-wideband impedance sensor  

DOEpatents

The ultra-wideband impedance sensor (UWBZ sensor, or Z-sensor) is implemented in differential and single-ended configurations. The differential UWBZ sensor employs a sub-nanosecond impulse to determine the balance of an impedance bridge. The bridge is configured as a differential sample-and-hold circuit that has a reference impedance side and an unknown impedance side. The unknown impedance side includes a short transmission line whose impedance is a function of the near proximity of objects. The single-ended UWBZ sensor eliminates the reference side of the bridge and is formed of a sample and hold circuit having a transmission line whose impedance is a function of the near proximity of objects. The sensing range of the transmission line is bounded by the two-way travel time of the impulse, thereby eliminating spurious Doppler modes from large distant objects that would occur in a microwave CW impedance bridge. Thus, the UWBZ sensor is a range-gated proximity sensor. The Z-sensor senses the near proximity of various materials such as metal, plastic, wood, petroleum products, and living tissue. It is much like a capacitance sensor, yet it is impervious to moisture. One broad application area is the general replacement of magnetic sensors, particularly where nonferrous materials need to be sensed. Another broad application area is sensing full/empty levels in tanks, vats and silos, e.g., a full/empty switch in water or petroleum tanks.

McEwan, Thomas E. (Livermore, CA)

1999-01-01

129

Power-efficient UWB generation based on hybrid of optical fiber link and RF circuits  

NASA Astrophysics Data System (ADS)

We propose a low cost solution to generate power efficient ultra-wideband (UWB) radio frequency (RF) signal based on the hybrid of optical fiber and RF circuits. In our solution, any return-to-zero (RZ) optical pulse with enough bandwidth is transmitted over optical fiber first, then converted to a power-efficient UWB pulse by an electrical bandpass filter (EBPF) with a passband of 3.1-10.6 GHz. The transmission and modulation of UWB signal is processed in optical domain, whereas the generation of UWB is processed in electrical domain. This solution embodies the advantages of both low-loss long-haul transmission of optical fiber and low-cost mature RF circuits. Both UWB modulations of on-off keying (OOK) and binary phase shift keying (BPSK) are experimentally demonstrated. The impacts of RZ pulsewidth and the EBPF bandwidth on the UWB waveforms are also discussed.

Dong, Jianji; Yu, Yu; Huang, Dexiu; Zhang, Xinliang

2012-12-01

130

A reconfigurable software defined ultra-wideband impulse radio transceiver  

NASA Astrophysics Data System (ADS)

An ultra-wideband (UWB) software defined radio (SDR) implementation is presented. The developed impulse radio (IR) transceiver employs first order bandpass (BP) sampling at a conversion frequency which is four times the channel bandwidth. The subsampling architecture directly provides the RF signal avoiding any non-ideal mixer stages and reduces the requirements of digital signal processing implemented in a field programmable gate array (FPGA). The transmitter consists basically of a multi-Nyquist digital to analog converter (DAC), whereas the implemented matched filter (MF) receiver prototype employs a standard digitizing oscilloscope. This design can be adaptively reconfigured in terms of modulation, data rate, and channel equalization. The reconfigurable design is used for an extensive performance analysis of the quadrature phase shift keying (QPSK) modulation scheme investigating the influence of different antennas, amplifiers, narrowband interferers as well as different equalizer lengths. Even for distances up to 7 m in a multipath environment robust communication was achieved.

Blech, M. D.; Ott, A. T.; Neumeier, P.; Möller, M.; Eibert, T. F.

2010-09-01

131

An Exact Theoretical Approach to Performance Analysis of Low-duty UWB Multiple Access Systems  

Microsoft Academic Search

In this paper, we present an overview of our recent works on developing exact theoretical error probabilities for various low-duty ultra-wideband (UWB) multiple access systems. The exact method is simple and is based on the characteristic function (CF) method. The analysis is developed considering a general pulse shape and Nakagami fading channel. Note that Nakagami fading can model a wide-variety

Mohammad Azizur Rahman; Shigenobu Sasaki; Hisakazu Kikuchi

132

A New Type of Miniature Ultra-Wideband Band-Pass Filter with Coplanar Waveguide Fed  

NASA Astrophysics Data System (ADS)

A novel miniature ultra-wideband (UWB) bandpass filter with coplanar waveguide (CPW) fed is proposed. The size of the filter is reduced largely because of combining the wideband couple gap and parallel-coupled CPW line (not cascading multiple resonator), and the length of realized filter is only 0.42 ? g0 (? g0 is the guiding wavelength at central frequency). The measured insertion loss is less than 2.0 dB, and the group delay variation is less than 0.2 ns within the UWB passband. Basic agreement between the simulated and measured results has been achieved.

Yao, Chunhui; Zhang, Wenmei; Han, Liping; Ma, Runbo

2007-10-01

133

Ultra-wideband microwave imaging of breast cancer tumors via Bayesian inverse scattering  

NASA Astrophysics Data System (ADS)

We develop a new algorithm for ultra-wideband (UWB) microwave imaging of breast cancer tumors using Bayesian inverse scattering. A key feature of the proposed algorithm is that constitutive properties of breast tissues are reconstructed from scattered UWB microwave signals together with the confidence level of the reconstruction. Having such confidence level enables minimization of both false alarms and missed detections. Results from the application of the proposed algorithm demonstrate the accuracy in estimating both location and permittivity of breast tumors without the need for a priori knowledge of pointwise properties of the background breast tissue.

Fouda, A. E.; Teixeira, F. L.

2014-02-01

134

Compact Electromagnetic Bandgap Structures for Notch Band in Ultra-Wideband Applications  

PubMed Central

This paper introduces a novel approach to create notch band filters in the front-end of ultra-wideband (UWB) communication systems based on electromagnetic bandgap (EBG) structures. The concept presented here can be implemented in any structure that has a microstrip in its configuration. The EBG structure is first analyzed using a full wave electromagnetic solver and then optimized to work at WLAN band (5.15–5.825 GHz). Two UWB passband filters are used to demonstrate the applicability and effectiveness of the novel EBG notch band feature. Simulation results are provided for two cases studied. PMID:22163430

Rotaru, Mihai; Sykulski, Jan

2010-01-01

135

MODELS FOR UWB PULSES AND THEIR EFFECTS ON NARROWBAND DIRECT CONVERSION RECEIVERS  

E-print Network

the bandwidth of the UWB signal. 2. MODELS FOR UWB SIGNALS Perhaps the simplest UWB communication pulse waveform and generalizations of transmitted UWB pulse wave- forms have been developed, including sinusoidal bursts with variousMODELS FOR UWB PULSES AND THEIR EFFECTS ON NARROWBAND DIRECT CONVERSION RECEIVERS Leonard E. Miller

136

Ultra-wideband radar sensors and networks  

SciTech Connect

Ultra wideband radar motion sensors strategically placed in an area of interest communicate with a wireless ad hoc network to provide remote area surveillance. Swept range impulse radar and a heart and respiration monitor combined with the motion sensor further improves discrimination.

Leach, Jr., Richard R; Nekoogar, Faranak; Haugen, Peter C

2013-08-06

137

UWB Pulse Design and capability analyze base on PSWF  

Microsoft Academic Search

UWB is a new wireless communication technology, due to its extremely wide bandwidth, it becomes especially important to coexist with extant wireless communication systems. Pulse design is one of pivotal technologies to reduce the interference among these wireless communication systems. This thesis introduced a special function-----PSWF to design appropriate pulse waveform for UWB.

Liu Ping; Ning Jing

2007-01-01

138

Software-Defined Ultra-wideband Radio Communications: A New RF Technology for Emergency Response Applications  

SciTech Connect

Reliable wireless communication links for local-area (short-range) and regional (long-range) reach capabilities are crucial for emergency response to disasters. Lack of a dependable communication system can result in disruptions in the situational awareness between the local responders in the field and the emergency command and control centers. To date, all wireless communications systems such as cell phones and walkie-talkies use narrowband radio frequency (RF) signaling for data communication. However, the hostile radio propagation environment caused by collapsed structures and rubble in various disaster sites results in significant degradation and attenuation of narrowband RF signals, which ends up in frequent communication breakdowns. To address the challenges of reliable radio communication in disaster fields, we propose an approach to use ultra-wideband (UWB) or wideband RF waveforms for implementation on Software Defined Radio (SDR) platforms. Ultra-wideband communications has been proven by many research groups to be effective in addressing many of the limitations faced by conventional narrowband radio technologies. In addition, LLNL's radio and wireless team have shown significant success in field deployment of various UWB communications system for harsh environments based on LLNL's patented UWB modulation and equalization techniques. Furthermore, using software defined radio platform for UWB communications offers a great deal of flexibility in operational parameters and helps the radio system to dynamically adapt itself to its environment for optimal performance.

Nekoogar, F; Dowla, F

2009-10-19

139

Noise suppression in UWB transmitted reference systems  

Microsoft Academic Search

Transmitted reference (TR) systems have recently been proposed for ultra wideband (UWB) communications. They considerably simplify synchronization and channel estimation, which are known to be difficult problems in UWB communications. We extend existing receivers for TR-UWB systems by replacing the correlation operation by a linear combination of specific parts of the correlation and weighting the parts that have a small

Geert Leus; Aile-Jan van def Veen

2004-01-01

140

ULTRA WIDEBAND INTERFERENCE EFFECTS ON AN AMATEUR RADIO RECEIVER R. D. Wilson, R. D. Weaver, M.-H. Chung and R. A. Scholtz  

E-print Network

ULTRA WIDEBAND INTERFERENCE EFFECTS ON AN AMATEUR RADIO RECEIVER R. D. Wilson, R. D. Weaver, M of an amateur radio receiver in the presence of sinusoidal and UWB interference is stud- ied. We characterize will have on systems with which spectrum is shared. Radio amateurs are one of the groups concerned

Southern California, University of

141

Ultra-wideband conformal helmet antenna  

Microsoft Academic Search

This paper presents the development of an ultra-wideband (300 to 3000 MHz), vertically polarized, nearly omni-directional (in azimuth) communications antenna integrated into the camouflage cover of a standard military-issue Kevlar helmet. The Helmet Camouflage Cover Antenna (referred to as the “helmet antenna”) is one of three antennas (with the combined frequency coverage from 2 to 2000 MHz) based on the

J. Lebaric; Ah-Tuan Tan

2000-01-01

142

Ultra-wideband miniaturized microstrip patch antennas for wireless communications: Design guidelines and modeling  

NASA Astrophysics Data System (ADS)

The number of wireless communication applications continue to increase steadily, leading to competition for currently allocated frequency bands. Capacity issues in form of data rate and latency have always been a bottleneck for broadband wireless-communication usage. New communication systems like ultra-wideband (UWB) require larger bandwidth than what is normally utilized with traditional antenna techniques. The interest for compact consumer electronics is growing in the meantime, creating a demand on efficient and low profile antennas which can be integrated on a printed circuit board. The main objective of this thesis is to study, design, analyze and implement UWB low profile microstrip patch antenna that satisfy UWB technology requirements. Some methods to extend the bandwidth and other antenna parameters associated with wideband usages are studied. Several techniques are used for optimal UWB bandwidth performance of the UWB microstrip patch antenna. The performance parameters such as VSWR, Gain and radiation pattern of the UWB microstrip patch antenna is extensively investigated with simulations using FEKO. A set of simple design guidelines is proposed to provide approximate rules that result in optimum "first-pass" designs of probe-fed, miniaturized, low profile, microstrip UWB antennas using different bandwidth-enhancement techniques to satisfy UWB bandwidth that require minimal tuning.

Dandu, Varun Kumar

143

UTag: Long-range Ultra-wideband Passive Radio Frequency Tags  

SciTech Connect

Long-range, ultra-wideband (UWB), passive radio frequency (RF) tags are key components in Radio Frequency IDentification (RFID) system that will revolutionize inventory control and tracking applications. Unlike conventional, battery-operated (active) RFID tags, LLNL's small UWB tags, called 'UTag', operate at long range (up to 20 meters) in harsh, cluttered environments. Because they are battery-less (that is, passive), they have practically infinite lifetimes without human intervention, and they are lower in cost to manufacture and maintain than active RFID tags. These robust, energy-efficient passive tags are remotely powered by UWB radio signals, which are much more difficult to detect, intercept, and jam than conventional narrowband frequencies. The features of long range, battery-less, and low cost give UTag significant advantage over other existing RFID tags.

Dowla, F

2007-03-14

144

Ultra-wideband horn antenna with abrupt radiator  

DOEpatents

An ultra-wideband horn antenna transmits and receives impulse waveforms for short-range radars and impulse time-of flight systems. The antenna reduces or eliminates various sources of close-in radar clutter, including pulse dispersion and ringing, sidelobe clutter, and feedline coupling into the antenna. Dispersion is minimized with an abrupt launch point radiator element; sidelobe and feedline coupling are minimized by recessing the radiator into a metallic horn. Low frequency cut-off associated with a horn is extended by configuring the radiator drive impedance to approach a short circuit at low frequencies. A tapered feed plate connects at one end to a feedline, and at the other end to a launcher plate which is mounted to an inside wall of the horn. The launcher plate and feed plate join at an abrupt edge which forms the single launch point of the antenna. 8 figs.

McEwan, T.E.

1998-05-19

145

Ultra-wideband horn antenna with abrupt radiator  

DOEpatents

An ultra-wideband horn antenna transmits and receives impulse waveforms for short-range radars and impulse time-of flight systems. The antenna reduces or eliminates various sources of close-in radar clutter, including pulse dispersion and ringing, sidelobe clutter, and feedline coupling into the antenna. Dispersion is minimized with an abrupt launch point radiator element; sidelobe and feedline coupling are minimized by recessing the radiator into a metallic horn. Low frequency cut-off associated with a horn is extended by configuring the radiator drive impedance to approach a short circuit at low frequencies. A tapered feed plate connects at one end to a feedline, and at the other end to a launcher plate which is mounted to an inside wall of the horn. The launcher plate and feed plate join at an abrupt edge which forms the single launch point of the antenna.

McEwan, Thomas E. (Livermore, CA)

1998-01-01

146

A low-cost protocol and application for UWB localization  

Microsoft Academic Search

Range Radio by Advanced Ultra-Wideband Radio Technology, FP7-ICT-215669, www.euwb.eu) project has been an industry-led initiative of twenty-one major industrial and excellent academic organizations from Europe and Israel who have been targeting innovative improvement, adaptation, integration and application of short-range Ultra-Wideband Radio Technology (UWB-RT). EUWB has effectively leveraged and significantly enhanced the scientific knowledge base in the advanced UWB-RT and has

Christian KOCKS; Ernest SCHEIBER; Dong Xu; Alexander VIESSMANN; Shangbo Wang; Guido H. BRUCK; Peter JUNG

2009-01-01

147

Signal processing techniques for stepped frequency ultra-wideband radar  

NASA Astrophysics Data System (ADS)

The U.S. Army Research Laboratory (ARL) has developed the impulse-based, ground vehicle-based, forward-looking ultra-wideband (UWB), synthetic aperture radar (SAR) to detect concealed targets. Although the impulse-based architecture offers its own advantages, one of the important challenges is that when using this architecture it is very difficult to transmit a radar signal with an arbitrary bandwidth and shape. This feature is crucial for the radar to be compliant with the local frequency authority. In addition, being able to transmit signals with an arbitrary spectral shape is an important step in creating the next generation of smart (cognitive) radars. Therefore, we have designed a next-generation prototype radar to take advantage of the stepped frequency architecture. The design and building of the radar hardware is underway. In this paper, we study the radar transmit and acquisition scheme; the trade-offs between SAR image performance and various key radar parameters; and data reconstruction techniques for radar signals with an arbitrary spectrum. This study demonstrates performance, provides some guidelines for the radar design, and serves as a foundation for the signal and image processing stage.

Nguyen, Lam

2014-05-01

148

SEMICONDUCTOR INTEGRATED CIRCUITS: A 6-9 GHz ultra-wideband CMOS PA for China's ultra-wideband standard  

NASA Astrophysics Data System (ADS)

A 6-9 GHz ultra-wideband CMOS power amplifier (PA) for the high frequency band of China's UWB standard is proposed. Compared with the conventional band-pass filter wideband input matching methodology, the number of inductors is saved by the resistive feedback complementary amplifying topology presented. The output impendence matching network utilized is very simple but efficient at the cost of only one inductor. The measured S22 far exceeds that of similar work. The PA is designed and fabricated with TSMC 0.18 ?m 1P6M RF CMOS technology. The implemented PA achieves a power gain of 10 dB with a ripple of 0.6 dB, and S11 < -10 dB over 6-9 GHz, S22 < -35 dB over 4-10 GHz. The measured output power at the 1 dB compression point is over 3.5 dBm from 6 to 9 GHz. The PA dissipates a total power of 21 mW from a 1.8 V power supply. The chip size is 1.1 × 0.8 mm2.

Zhendong, Gao; Zhiqiang, Li; Haiying, Zhang

2010-09-01

149

Fiber-distributed Ultra-wideband noise radar with steerable power spectrum and colorless base station.  

PubMed

A fiber-distributed Ultra-wideband (UWB) noise radar was achieved, which consists of a chaotic UWB noise source based on optoelectronic oscillator (OEO), a fiber-distributed transmission link, a colorless base station (BS), and a cross-correlation processing module. Due to a polarization modulation based microwave photonic filter and an electrical UWB pass-band filter embedded in the feedback loop of the OEO, the power spectrum of chaotic UWB signal could be shaped and notch-filtered to avoid the spectrum-overlay-induced interference to the narrow band signals. Meanwhile, the wavelength-reusing could be implemented in the BS by means of the distributed polarization modulation-to-intensity modulation conversion. The experimental comparison for range finding was carried out as the chaotic UWB signal was notch-filtered at 5.2 GHz and 7.8 GHz or not. Measured results indicate that space resolution with cm-level could be realized after 3-km fiber transmission thanks to the excellent self-correlation property of the UWB noise signal provided by the OEO. The performance deterioration of the radar raised by the energy loss of the notch-filtered noise signal was negligible. PMID:24663829

Zheng, Jianyu; Wang, Hui; Fu, Jianbin; Wei, Li; Pan, Shilong; Wang, Lixian; Liu, Jianguo; Zhu, Ninghua

2014-03-10

150

Adaptive low-rank channel estimation for multi-band OFDM ultra-wideband communications  

NASA Astrophysics Data System (ADS)

In this paper, an adaptive channel estimation scheme based on the reduced-rank (RR) Wiener filtering (WF) technique is proposed for multi-band (MB) orthogonal frequency division multiplexing (OFDM) ultra-wideband (UWB) communication systems in multipath fading channels. This RR-WF-based algorithm employs an adaptive fuzzy-inference-controlled (FIC) filter rank. Additionally, a comparative investigation into various channel estimation schemes is presented as well for MB-OFDM UWB communication systems. As a consequence, the FIC RR-WF channel estimation algorithm is capable of producing the bit-error-rate (BER) performance similar to that of the full-rank WF channel estimator and superior than those of other interpolation-based channel estimation schemes.

Hu, Chia-Chang; Lee, Shih-Chang

2011-12-01

151

Fiber-connected UWB sensor network for high-resolution localization using optical time-division multiplexing.  

PubMed

A fiber-connected ultra-wideband (UWB) sensor network for high-resolution localization which consists of a central station and several sensor nodes is proposed and demonstrated. To make the central station easily identify the received UWB pulses from different sensor nodes, optical time-division multiplexing (OTDM), realized by inserting a certain length of optical fiber between every two sensor nodes, is implemented. Due to the OTDM technology, the UWB pulses received by different sensors are mapped into different time slots, so neither parameter estimation nor clock synchronization is required in the UWB sensor node. All complex signal processing is completed in the central station, which greatly improve the localization accuracy and simplify the system. A proof-of-concept experiment for two-dimensional localization is demonstrated. Spatial resolution as high as 3.9 cm is achieved. PMID:24103995

Fu, Jianbin; Pan, Shilong

2013-09-01

152

The effects of the human body on UWB signal propagation in an indoor environment  

Microsoft Academic Search

Ultra-wideband (UWB) communication systems are investigated for their ability to operate in dense multipath environments. While a great deal of time and effort has been spent characterizing both the indoor and outdoor UWB channels, the effects of human body interaction with a close proximity UWB antenna remains unexplored. Measurements of a commercially available UWB antenna performance in an anechoic chamber

T. B. Welch; Randall L. Musselman; Bomono A. Emessiene; Phillip D. Gift; Daniel K. Choudhury; Derek N. Cassadine; Scott M. Yano

2002-01-01

153

Printed-Circuit Antennas for Ultra-Wideband Monitoring Applications  

E-print Network

a time-domain technique (CST Microwave Studio) and feeding an UWB pulse to the input of the microstrip-spread and addresses issues such as EIRP compliance [2], immunity tests [3], interference [4], high-power microwave

Bornemann, Jens

154

Photonic generation and wireless transmission of different pulse modulation formats for high-speed impulse radio ultrawideband over fiber systems  

NASA Astrophysics Data System (ADS)

Novel methods on photonic generation of different pulse modulation formats for impulse radio ultra-wideband (IR-UWB) over fiber application is overviewed. A flexible, high-speed and power-efficient photonic on-off keying and binary phase shift keying modulated IR-UWB over fiber communication system is proposed and demonstrated. IR-UWB transmission over 20km fiber and 0.25m wireless link without any compensation is presented. The transmission performance for both modulation formats is evaluated and compared by measuring eye diagrams and the electrical spectra.

Xie, Shizhong; Chen, Hongwei; Chen, Minghua; Yang, Sigang; Li, Pengxiao

2011-12-01

155

Adaptive signal processing algorithm for remote detection of heart rate (HR) using ultra-wideband waveforms based on principal component analysis.  

PubMed

Ultra-Wideband (UWB) technology provides a convenient approach for remote biomedical sensing and vital signs monitoring in humans. In this paper, a specific algorithm is proposed to improve the ability of Heart Rate (HR) detection. Unlike previous methods for remote HR detection, the proposed method provides an adaptive filter based on respiration and heart rate parameters obtained from UWB waveforms. The algorithm is capable of detecting heart rate by changing the adaptive filter parameters accordingly. The proposed method is employed on real life data collected by UWB transceiver. According to experiments, it is concluded that the proposed technique is able to handle remote detection of different heart rates accurately. PMID:19963914

Sharifahmadian, Ershad; Ahmadian, Alireza

2009-01-01

156

Ultra-Wideband Time-Difference-of-Arrival High Resolution 3D Proximity Tracking System  

NASA Technical Reports Server (NTRS)

This paper describes a research and development effort for a prototype ultra-wideband (UWB) tracking system that is currently under development at NASA Johnson Space Center (JSC). The system is being studied for use in tracking of lunar./Mars rovers and astronauts during early exploration missions when satellite navigation systems are not available. U IATB impulse radio (UWB-IR) technology is exploited in the design and implementation of the prototype location and tracking system. A three-dimensional (3D) proximity tracking prototype design using commercially available UWB products is proposed to implement the Time-Difference- Of-Arrival (TDOA) tracking methodology in this research effort. The TDOA tracking algorithm is utilized for location estimation in the prototype system, not only to exploit the precise time resolution possible with UWB signals, but also to eliminate the need for synchronization between the transmitter and the receiver. Simulations show that the TDOA algorithm can achieve the fine tracking resolution with low noise TDOA estimates for close-in tracking. Field tests demonstrated that this prototype UWB TDOA High Resolution 3D Proximity Tracking System is feasible for providing positioning-awareness information in a 3D space to a robotic control system. This 3D tracking system is developed for a robotic control system in a facility called "Moonyard" at Honeywell Defense & System in Arizona under a Space Act Agreement.

Ni, Jianjun; Arndt, Dickey; Ngo, Phong; Phan, Chau; Dekome, Kent; Dusl, John

2010-01-01

157

Generalized equivalent circuit model for ultra wideband antenna structure with double steps for energy scavenging  

NASA Astrophysics Data System (ADS)

There are various types of UWB antennas can be used to scavenge energy from the air and one of them is the printed disc monopole antenna. One of the new challenges imposed on ultra wideband is the design of a generalized antenna circuit model. It is developed in order to extract the inductance and capacitance values of the UWB antennas. In this research work, the developed circuit model can be used to represent the rectangular printed disc monopole antenna with double steps. The antenna structure is simulated with CST Microwave Studio, while the circuit model is simulated with AWR Microwave Office. In order to ensure the simulation result from the circuit model is accurate, the circuit model is also simulated using Mathlab program. The developed circuit model is found to be able to depict the actual UWB antenna. Energy harvesting from environmental wirelessly is an emerging method, which forms a promising alternative to existing energy scavenging system. The developed UWB can be used to scavenge wideband energy from electromagnetic wave present in the environment.

>Oon Kheng Heong, Goh Chin; Chakrabarty, Chandan Kumar; >Goh Tian Hock,

2013-06-01

158

Ultra wideband ground penetrating radar imaging of heterogeneous solids  

DOEpatents

A non-invasive imaging system for analyzing engineered structures comprises pairs of ultra wideband radar transmitters and receivers in a linear array that are connected to a timing mechanism that allows a radar echo sample to be taken at a variety of delay times for each radar pulse transmission. The radar transmitters and receivers are coupled to a position determining system that provides the x,y position on a surface for each group of samples measured for a volume from the surface. The radar transmitter and receivers are moved about the surface, e.g., attached to the bumper of a truck, to collect such groups of measurements from a variety of x,y positions. Return signal amplitudes represent the relative reflectivity of objects within the volume and the delay in receiving each signal echo represents the depth at which the object lays in the volume and the propagation speeds of the intervening material layers. Successively deeper z-planes are backward propagated from one layer to the next with an adjustment for variations in the expected propagation velocities of the material layers that lie between adjacent z-planes.

Warhus, John P. (Brentwood, CA); Mast, Jeffrey E. (Livermore, CA)

1998-01-01

159

Ultra wideband ground penetrating radar imaging of heterogeneous solids  

DOEpatents

A non-invasive imaging system for analyzing engineered structures comprises pairs of ultra wideband radar transmitters and receivers in a linear array that are connected to a timing mechanism that allows a radar echo sample to be taken at a variety of delay times for each radar pulse transmission. The radar transmitters and receivers are coupled to a position determining system that provides the x,y position on a surface for each group of samples measured for a volume from the surface. The radar transmitter and receivers are moved about the surface, e.g., attached to the bumper of a truck, to collect such groups of measurements from a variety of x,y positions. Return signal amplitudes represent the relative reflectivity of objects within the volume and the delay in receiving each signal echo represents the depth at which the object lays in the volume and the propagation speeds of the intervening material layers. Successively deeper z-planes are backward propagated from one layer to the next with an adjustment for variations in the expected propagation velocities of the material layers that lie between adjacent z-planes. 11 figs.

Warhus, J.P.; Mast, J.E.

1998-11-10

160

2494 IEEE JOURNAL OF SOLID-STATE CIRCUITS, VOL. 48, NO. 10, OCTOBER 2013 64-Channel UWB Wireless Neural Vector  

E-print Network

Velazquez, and Roman Genov, Senior Member, IEEE Abstract--An ultra wideband (UWB) 64-channel responsive with tunable switched-capacitor (SC) bandpass filters, 64 multiplying 8-bit SAR ADCs, 64 pro- grammable 16-tap

Genov, Roman

161

Real-time kinematic surveying using tightly-coupled GPS and ultra-wideband ranging  

NASA Astrophysics Data System (ADS)

Ultra-wideband (UWB) ranging radios, an emerging technology that offers precise, short distance, range measurements are investigated as a method to augment carrier-phase GPS positioning. This thesis begins with a discussion of radio-frequency based methods of augmenting high precision GPS and proposes to utilize UWB ranging technology in a tightly-coupled GPS and UWB position estimation filter. This thesis then provides an overview of UWB in the context of ranging applications and assesses the precision and accuracy of UWB ranging from both a theoretical perspective and a practical perspective using real data. Two types of commercially available UWB ranging radios are introduced which are used in testing. Actual ranging accuracy is assessed from line-of-sight testing in benign signal conditions and in outdoor testing with line-of-sight obstructions and strong reflection sources. A tightly-coupled GPS and UWB real-time kinematic (RTK) estimation method is developed and the performance of the system is evaluated in static and kinematic testing. The results of static testing show that the integrated solution provides better accuracy, better ability to resolve integer ambiguities and enhanced fixed ambiguity solution availability compared with GPS alone. The results of kinematic testing demonstrate that UWB errors can be successfully estimated in a real-time filter. In static and kinematic testing in a degraded GPS environment created by artificially inducing a 40° satellite elevation mask, subdecimetre accuracy was maintained. The tightly-coupled system is also tested to survey several external corner points of an eight story building. The tightly-coupled solution is compared to GPS-only, UWB-only, and loosely-coupled solutions. Sub-metre level solutions are maintained using tight-coupling in conditions where the solutions from the other three approaches are either unavailable or unreliable. The thesis also provides a novel and efficient method for deploying UWB reference stations and performing the RTK survey. Tightly-coupled GPS+UWB for RTK surveying is a promising new technology that extends RTK surveying to new environments. In addition, in marginal GPS-only surveying environments, position accuracy and RTK solution availability are improved substantially.

Macgougan, Glenn D.

162

An omnidirectional and low-VSWR antenna for the FCC-approved UWB frequency band  

Microsoft Academic Search

Recently, encouraged by deregulation ultra-wideband (UWB) technology has attracted attention for use in communication and sensing applications in the commercial domain. In February 2002 the Federal Communications Commission (FCC) in the United States conditionally waived unlicensed operation of the personal UWB products in the private sector. In this paper, we constructed a prototype antenna for the FCC approved UWB frequency

Takuya Taniguchi; Takehiko Kobayashi

2003-01-01

163

Generic z-domain discrete-time transfer function estimation for ultra-wideband  

E-print Network

regime based upon prolate spheroidal wave functions (PSWFs) [3] is employed for transmitting the UWB-PSWF) and equating it with (5) we obtain the value for bl with UWB-PSWF pulse duration and energy T and E

Chen, Sheng

164

Small and Broadband Planar Antennas for UWB Wireless Communication Applications  

NASA Astrophysics Data System (ADS)

Due to the unique features of ultra-wideband (UWB) wireless communication systems, the antenna design with small size and broad band-widths for transfer response and systems gain are required. A novel rolled planar antenna is proposed to meet the requirements for omni-directional UWB wireless communication applications.

Chen, Z. N.

165

Small and Broadband Planar Antennas for UWB Wireless Communication Applications  

Microsoft Academic Search

Due to the unique features of ultra-wideband (UWB) wireless communication systems, the antenna design with small size and broad band-widths for transfer response and systems gain are required. A novel rolled planar antenna is proposed to meet the requirements for omni-directional UWB wireless communication applications.

Z. N. Chen

2007-01-01

166

UWB Microwave Monopulse Radar System for breast cancer detection  

Microsoft Academic Search

The concept of an Ultra Wideband (UWB) Monopulse Microwave Radar System for detection and location of breast cancer is described. The system uses a two-element Tapered Slot Antenna (TSA) array accompanied by a UWB 180° hybrid which scans the breast. When the breast tissue features symmetry with respect to the array axis and the hybrid enables the 180° out phase

Marek E. Bialkowski; Yifan Wang; Amin Abbosh

2010-01-01

167

Design of UWB pulse radio transceiver using statistical correlation technique in frequency domain  

NASA Astrophysics Data System (ADS)

In this paper, we propose a new technique to extract low power UWB pulse radio signals, near to noise level, using statistical correlation technique in frequency domain. The receiver consists of many narrow bandpass filters which extract energy either from transmitted UWB signal, interfering channels or noise. Transmitted UWB data can be eliminated by statistical correlation of multiple bandpass filter outputs. Super-regenerative oscillators, tuned within UWB spectrum, are designed as bandpass filters. Summers and comparators perform statistical correlation.

Anis, M.; Tielert, R.

2007-06-01

168

Technical note: a novel approach to the detection of estrus in dairy cows using ultra-wideband technology.  

PubMed

Detection of estrus is a key determinant of profitability of dairy herds, but estrus is increasingly difficult to observe in the modern dairy cow with shorter duration and less-intense estrus. Concurrent with the unfavorable correlation between milk yield and fertility, estrus-detection rates have declined to less than 50%. We tested ultra-wideband (UWB) radio technology (Thales Research & Technology Ltd., Reading, UK) for proof of concept that estrus could be detected in dairy cows (two 1-wk-long trials; n=16 cows, 8 in each test). The 3-dimensional positions of 12 cows with synchronized estrous cycles and 4 pregnant control cows were monitored continuously using UWB mobile units operating within a network of 8 base units for a period of 7d. In the study, 10 cows exhibited estrus as confirmed by visual observation, activity monitoring, and milk progesterone concentrations. Automated software was developed for analysis of UWB data to detect cows in estrus and report the onset of estrus in real time. The UWB technology accurately detected 9 out of 10 cows in estrus. In addition, UWB technology accurately confirmed all 6 cows not in estrus. In conclusion, UWB technology can accurately detect estrus and hence we have demonstrated proof of concept for a novel technology that has significant potential to improve estrus-detection rates. PMID:23910546

Homer, E M; Gao, Y; Meng, X; Dodson, A; Webb, R; Garnsworthy, P C

2013-10-01

169

Matching layer for path loss reduction in ultra wideband implant communications.  

PubMed

Real-time monitoring of various physiological signals is of utmost importance for the treatment of chronic conditions. Radio technology can enable real-time sensing and collection of physiological data to facilitate timely medication and early pre-hospital management of patients. This can be realized with the aid of implantable biomedical sensors with the capability to transmit wirelessly the collected information to an external unit for display and analysis. Currently, commercial wireless medical implantable sensors operate in frequencies below 1 GHz with narrowband signals. Recently, it has been demonstrated that ultra wideband (UWB) signals could be also used for the radio interface of these devices. However, establishing an implant communication link in the allocated UWB spectrum of 3.1-10.6 GHz is challenging. The attenuation of UWB signals propagating through biological tissues at these frequencies is high. Part of these path losses are caused by the impedance mismatch between the two propagation environments (i.e., air and biological tissues) that constitute an implant communication link. This mismatch results in inefficient power transmission of the radio waves. In this paper we propose the use of a layer of dielectric material that can be applied on the patient's skin. The permittivity value of this matching layer has to be chosen such that wave coupling is maximized. Through numerical simulations we determined the appropriate permittivity value of a matching layer for UWB implant communication links in the human thorax for 1-6 GHz. Path loss reduction of up to 10 dB can be obtained in this frequency band. These results can help improve the use of UWB signals for other in-body biomedical devices like the wireless capsule endoscope (WCE). PMID:25571604

Chavez-Santiago, Raul; Khaleghi, Ali; Balasingham, Ilangko

2014-08-01

170

3D positioning scheme exploiting nano-scale IR-UWB orthogonal pulses.  

PubMed

In these days, the development of positioning technology for realizing ubiquitous environments has become one of the most important issues. The Global Positioning System (GPS) is a well-known positioning scheme, but it is not suitable for positioning in in-door/building environments because it is difficult to maintain line-of-sight condition between satellites and a GPS receiver. To such problem, various positioning methods such as RFID, WLAN, ZigBee, and Bluetooth have been developed for indoor positioning scheme. However, the majority of positioning schemes are focused on the two-dimension positioning even though three-dimension (3D) positioning information is more useful especially in indoor applications, such as smart space, U-health service, context aware service, etc. In this paper, a 3D positioning system based on mutually orthogonal nano-scale impulse radio ultra-wideband (IR-UWB) signals and cross array antenna is proposed. The proposed scheme uses nano-scale IR-UWB signals providing fine time resolution and high-resolution multiple signal specification algorithm for the time-of-arrival and the angle-of-arrival estimation. The performance is evaluated over various IEEE 802.15.4a channel models, and simulation results show the effectiveness of proposed scheme. PMID:21970578

Kim, Nammoon; Kim, Youngok

2011-01-01

171

3D positioning scheme exploiting nano-scale IR-UWB orthogonal pulses  

NASA Astrophysics Data System (ADS)

In these days, the development of positioning technology for realizing ubiquitous environments has become one of the most important issues. The Global Positioning System (GPS) is a well-known positioning scheme, but it is not suitable for positioning in in-door/building environments because it is difficult to maintain line-of-sight condition between satellites and a GPS receiver. To such problem, various positioning methods such as RFID, WLAN, ZigBee, and Bluetooth have been developed for indoor positioning scheme. However, the majority of positioning schemes are focused on the two-dimension positioning even though three-dimension (3D) positioning information is more useful especially in indoor applications, such as smart space, U-health service, context aware service, etc. In this paper, a 3D positioning system based on mutually orthogonal nano-scale impulse radio ultra-wideband (IR-UWB) signals and cross array antenna is proposed. The proposed scheme uses nano-scale IR-UWB signals providing fine time resolution and high-resolution multiple signal specification algorithm for the time-of-arrival and the angle-of-arrival estimation. The performance is evaluated over various IEEE 802.15.4a channel models, and simulation results show the effectiveness of proposed scheme.

Kim, Nammoon; Kim, Youngok

2011-10-01

172

Photonic generation of millimeter-wave ultra-wideband signal using phase modulation to intensity modulation conversion and frequency up-conversion  

NASA Astrophysics Data System (ADS)

We propose and experimentally demonstrate the generation of a pair of polarity-reversed 24 GHz millimeter-wave (MMW) ultra-wideband (UWB) monocycles. The scheme is realized by using delay interferometer (DI) based phase modulation to intensity modulation (PM-IM) conversion and carrier suppression modulation (CSM) based frequency up-conversion. The phase modulation is realized by using either electro-optic phase modulator (EOPM) or cross phase modulation (XPM) in semiconductor optical amplifier (SOA), which is an all-optical approach to obtaining baseband UWB signals, respectively. After frequency up-converted by using CSM in a Mach-Zehnder modulator (MZM), a pair of polarity-reversed 24 GHz MMW-UWB signals complying with the Federal Communication Committee (FCC) requirements is generated. The bi-phase modulation (BPM) of 24 GHz MMW-UWB signals can also be realized by electrically switching the bias voltage of delay interferometer.

Yu, Yuan; Dong, Jianji; Li, Xiang; Zhang, Xinliang

2012-04-01

173

All-optical UWB pulse generation using sum-frequency generation in a PPLN waveguide.  

PubMed

We propose and demonstrate a novel approach to optically generate ultrawideband (UWB) monocycle pulses by exploiting the parametric attenuation effect of sum-frequency generation (SFG) in a periodically poled lithium niobate (PPLN) waveguide. The SFG process changes the continuous-wave pump into dark optical pulse pump with undershoot, resulting in the generation of UWB monocycle through the combination of input signal and output pump with proper relative time advance/delay. Pairs of polarity-inverted UWB monocycle pulses meeting the UWB definition of U. S. Federal Communications Commission (FCC, part 15) are successfully obtained in the experiment. PMID:19259191

Wang, Jian; Sun, Qizhen; Sun, Junqiang; Zhang, Weiwei

2009-03-01

174

A Transformer Noise-Canceling Ultra-Wideband CMOS Low-Noise Amplifier  

NASA Astrophysics Data System (ADS)

Previously reported wideband CMOS low-noise amplifiers (LNAs) have difficulty in achieving both wideband input impedance matching and low noise performance at low power consumption and low supply voltage. We present a transformer noise-canceling wideband CMOS LNA based on a common-gate topology. The transformer, composed of the input and shunt-peaking inductors, partly cancels the noise originating from the common-gate transistor and load resistor. The combination of the transformer with an output series inductor provides wideband input impedance matching. The LNA designed for ultra-wideband (UWB) applications is implemented in a 90nm digital CMOS process. It occupies 0.12mm2 and achieves |S11| < -10dB, NF < 4.4dB, and |S21| > 9.3dB across 3.1-10.6GHz with a power consumption of 2.5mW from a 1.0V supply. These results show that the proposed topology is the most suitable for low-power and low-voltage UWB CMOS LNAs.

Kihara, Takao; Matsuoka, Toshimasa; Taniguchi, Kenji

175

Ultra-wideband sensors for improved magnetic resonance imaging, cardiovascular monitoring and tumour diagnostics.  

PubMed

The specific advantages of ultra-wideband electromagnetic remote sensing (UWB radar) make it a particularly attractive technique for biomedical applications. We partially review our activities in utilizing this novel approach for the benefit of high and ultra-high field magnetic resonance imaging (MRI) and other applications, e.g., for intensive care medicine and biomedical research. We could show that our approach is beneficial for applications like motion tracking for high resolution brain imaging due to the non-contact acquisition of involuntary head motions with high spatial resolution, navigation for cardiac MRI due to our interpretation of the detected physiological mechanical contraction of the heart muscle and for MR safety, since we have investigated the influence of high static magnetic fields on myocardial mechanics. From our findings we could conclude, that UWB radar can serve as a navigator technique for high and ultra-high field magnetic resonance imaging and can be beneficial preserving the high resolution capability of this imaging modality. Furthermore it can potentially be used to support standard ECG analysis by complementary information where sole ECG analysis fails. Further analytical investigations have proven the feasibility of this method for intracranial displacements detection and the rendition of a tumour's contrast agent based perfusion dynamic. Beside these analytical approaches we have carried out FDTD simulations of a complex arrangement mimicking the illumination of a human torso model incorporating the geometry of the antennas applied. PMID:22163498

Thiel, Florian; Kosch, Olaf; Seifert, Frank

2010-01-01

176

Ultra-Wideband Sensors for Improved Magnetic Resonance Imaging, Cardiovascular Monitoring and Tumour Diagnostics  

PubMed Central

The specific advantages of ultra-wideband electromagnetic remote sensing (UWB radar) make it a particularly attractive technique for biomedical applications. We partially review our activities in utilizing this novel approach for the benefit of high and ultra-high field magnetic resonance imaging (MRI) and other applications, e.g., for intensive care medicine and biomedical research. We could show that our approach is beneficial for applications like motion tracking for high resolution brain imaging due to the non-contact acquisition of involuntary head motions with high spatial resolution, navigation for cardiac MRI due to our interpretation of the detected physiological mechanical contraction of the heart muscle and for MR safety, since we have investigated the influence of high static magnetic fields on myocardial mechanics. From our findings we could conclude, that UWB radar can serve as a navigator technique for high and ultra-high field magnetic resonance imaging and can be beneficial preserving the high resolution capability of this imaging modality. Furthermore it can potentially be used to support standard ECG analysis by complementary information where sole ECG analysis fails. Further analytical investigations have proven the feasibility of this method for intracranial displacements detection and the rendition of a tumour’s contrast agent based perfusion dynamic. Beside these analytical approaches we have carried out FDTD simulations of a complex arrangement mimicking the illumination of a human torso model incorporating the geometry of the antennas applied. PMID:22163498

Thiel, Florian; Kosch, Olaf; Seifert, Frank

2010-01-01

177

Ultra-wideband source using gallium arsenide photoconductive semiconductor switches  

Microsoft Academic Search

An ultrawide-band (UWB) pulse generator based on high-gain (lock-on mode) gallium arsenide (GaAs) photoconductive semiconductor switches (PCSS's) is presented. Revised PCSS contact design shows improved performance in hold-off field, on-state switch potential, and switching jitter, while reducing the switch volume by 75% compared to previous designs. A compact laser diode module operates at 904 nm and triggers the PCSS at

Jon S. H. Schoenberg; Jeffrey W. Burger; J. Scott Tyo; Michael D. Abdalla; Michael C. Skipper; Walter R. Buchwald

1997-01-01

178

Equalization for Multiband OFDM based UWB Systems  

Microsoft Academic Search

The focus for ultra-wideband (UWB) technology has recently shifted to applications involving short-range, high-speed wireless communications like IEEE 802.15.3a for personal area network (PAN). FCC defines UWB signals as one that occupies more than 500 MHz bandwidth in the 3.1 to 10.6 GHz band and meets the output power limit of -41.3 dBm\\/MHz. This paper addresses the problem of equalizer

Baijayanta Ray; P. K. Venkataraghavan; Sriram Balasubramanian

2007-01-01

179

On the analysis of UWB communication channels  

Microsoft Academic Search

Ultra-wideband (UWB) communication systems have been proposed for use in dense multipath or shadowed environments. Given the bandwidth of the signals involved, traditional signal processing techniques are often not applicable to the analysis of UWB waveforms. In particular, many array signal processing techniques for determining the angle-of-arrival which make use of a narrowband assumption are not suitable. An iterative algorithm

J. M. Cramer; R. A. Scholtz; M. Z. Win

1999-01-01

180

Power control for interference mitigation between coexisting UWB systems  

Microsoft Academic Search

In this paper, we investigate the coexistence issue of two type of ultra-wideband (UWB) systems under IEEE 802.15.3a, i.e. Direct-Sequence UWB and MultiBand-Orthogonal Frequency Division Multiplexing UWB. The mutual interference of such coexistence scenarios is analyzed by physical layer Monte Carlo simulations. We observe severe and asymmetric performance degradation due to the mutual interference between the two systems. Therefore, we

Yongjing Zhang; Haitao Wu; Qian Zhang; Ping Zhang

2006-01-01

181

LTCC-based ultra-wideband Linearly Tapered Slot Antenna design guidelines  

Microsoft Academic Search

In this paper, the design of antipodal non-planar linearly tapered slot antenna (LTSA) designed in LTCC technology with wide bandwidth operation for ultra-wideband applications and a practical design guideline of LTCC-based ultra wideband LTSA is presented. The LTCC-based ultra wideband LTSA characteristics are investigated and then compared to a compact antipodal LTCC-based Vivaldi design. Using microstrip feeding technique, the antenna

Ziad El-Khatib; Leonard MacEachern; Samy A. Mahmoud

2009-01-01

182

A COMPACT ULTRA-WIDEBAND MICROSTRIP ANTENNA WITH MULTIPLE NOTCHES  

Microsoft Academic Search

In this paper, a new compact circular monopole ultra- wideband antenna with multiple narrow bands notched is proposed, which is implemented by using the existing techniques, such as loading a L-type band-stop filter, inserting a split ring resonator (SRR), and the method we proposed that connecting L branches on the radiation disk. Four sharp notches at 2.4GHz, 3.5 GHz, 5.5

C. Yin; L. Ruan; S.-G. Mo; Jia-Hui Chu

2008-01-01

183

Ultra-wideband Active Receiving Array Antenna with Dual Polarization  

NASA Astrophysics Data System (ADS)

This chapter presents results of the investigations directed to creation of large ultra-wideband active receiving array antennas with dual polarization. The array element is made on the basis of two crossed electric dipoles. Each arm of the dipoles is loaded to the single-stage FET amplifier. Four such elements form a 2 × 2 module being a component of a multielement array antenna.

Koshelev, V. I.; Balzovsky, E. V.; Buyanov, Yu. I.

184

Detect and Avoid Procedure for UWB Interference Mitigation on Narrowband Systems  

Microsoft Academic Search

Detect and avoid procedures (DAA) are helpful to solve coexistence issues between ultra-wideband (UWB) devices and existing narrowband system operating in the same area and at the same time. We consider a system scenario where a narrowband UMTS terminal is considered to be primary and UWB devices create a secondary network on a local area basis. DAA procedures are only

A. Durantini; R. Giuliano; F. Mazzenga; J. Hernandez; M. B. Villarroya

2006-01-01

185

Demo: Prototyping UWB-Enabled EnHANTs Jianxun Zhu, Gerald Stanje, Robert Margolies, Maria Gorlatova,  

E-print Network

-low-power ultra- wideband (UWB) communications and in organic semiconductor- based energy harvesting materials@, bv2152@, luca@cs., kinget@ee., johnkym@ee., gil@ee.]columbia.edu ABSTRACT Energy Harvesting Active with a UWB Transceiver and an energy harvest- ing module (EHM) that allows demonstrating energy harvesting

Carloni, Luca

186

Microwave and millimeter-wave rectifying circuit arrays and ultra-wideband antennas for wireless power transmission and communications  

E-print Network

because of demand for high data-rate transmission. Hence, ultra-wideband antennas have received much attention in mobile wireless communications. Planar monopole ultra-wideband antennas for UHF, microwave, and millimeter-wave bands are developed, with many...

Ren, Yu-Jiun

2009-05-15

187

A low-cost protocol and application for UWB localization, exploiting cross-layer design and cognitive radio aspects  

Microsoft Academic Search

The EUWB (Coexisting Short Range Radio by Advanced Ultra-Wideband Radio Technology, FP7-ICT-215669, www.euwb.eu) project has been an industry-led initiative of twenty-one major industrial and excellent academic organizations from Europe and Israel targeting innovative improvement, adaptation, integration and application of short- range Ultra-Wideband Radio Technology (UWB-RT). Started in April 2008, the EUWB project has leveraged and enhanced the scientific knowledge base

Christian KOCKS; Ernest SCHEIBER; Alexander VIESSMANN; Dong Xu; Shangbo Wang; Guido H. BRUCK; Peter JUNG

2009-01-01

188

Performance Evaluation of a UWB-RFID System for Potential Space Applications  

NASA Technical Reports Server (NTRS)

This talk presents a brief overview of the ultra-wideband (UWB) RFID system with emphasis on the performance evaluation of a commercially available UWB-RFID system. There are many RFID systems available today, but many provide just basic identification for auditing and inventory tracking. For applications that require high precision real time tracking, UWB technology has been shown to be a viable solution. The use of extremely short bursts of RF pulses offers high immunity to interference from other RF systems, precise tracking due to sub-nanosecond time resolution, and robust performance in multipath environments. The UWB-RFID system Sapphire DART (Digital Active RFID & Tracking) will be introduced in this talk. Laboratory testing using Sapphire DART is performed to evaluate its capability such as coverage area, accuracy, ease of operation, and robustness. Performance evaluation of this system in an operational environment (a receiving warehouse) for inventory tracking is also conducted. Concepts of using the UWB-RFID technology to track astronauts and assets are being proposed for space exploration.

Phan, Chan T.; Arndt, D.; Ngo, P.; Gross, J.; Ni, Jianjun; Rafford, Melinda

2006-01-01

189

Matched filter design optimisation for UWB receiver for sensor network application  

NASA Astrophysics Data System (ADS)

Ultra Wideband (UWB) communications is one of the possible solutions for future wireless personal area network (WPAN) applications. The Federal Communications Commission (FCC), in the USA, allocated 7.5 GHz of unlicensed frequency bandwidth from 3.1 GHz to 10.6 GHz for UWB communication. It is an available spectrum which can be utilised for data communication using different technologies complying with FCC regulations. This paper presents a brief overview of the world wide regulations and Institute of Electrical and Electronic Engineers (IEEE) standardisation updates for UWB. It also focuses on the wireless sensor network application and the use of UWB communications in biomedical sensor networks. The paper aims at the design and implementation of an optimised pulsed matched filter (OPMF) used in the digital backend of a UWB radio. The optimisations are performed at the architectural and circuit level in order to reduce hardware complexity and reduced power. The OPMF is successfully implemented using the application specific integrated circuit (ASIC) design methodology and the results are compared with those obtained in previous implementation. The OPMF implementation presented in this paper yields improved characteristics such as reduction in area, almost 25% power reduction and better timing.

Naik, Rohit; Singh, Jugdutt; Veljanovski, Ronny

2005-12-01

190

A Hybrid TDOA/RSS Localization Algorithm Based on UWB Ranging in Underground Mines  

NASA Astrophysics Data System (ADS)

Ultra-Wideband technology is regarded by many as one of the future key technologies in communications and positioning. In this paper a TDOA/RSS hybrid positioning algorithm is described for accurate underground mine localization of a sensor in a network of known beacons. The sensor measures the range to the beacons using an Ultra-Wideband (UWB) signal and uses statistical inference to correct for the error due to multipath and NLOS in underground mine. It shows that a TDOA/RSS algorithm can be used to improved positioning accuracy over beacon measurement. Simulation results show perfect performance with UWB ranging and TDOA/RSS hybrid localization algorithm.

Zhu, Daixian; Yi, Kechu

191

Low-cost PCB antenna for UWB applications  

Microsoft Academic Search

This letter presents a low-cost knight's helm shape double-sided printed circuit board (PCB) antenna of size 3 cm×3 cm for ultra-wideband (UWB) application. The antenna has a return loss of more than 10 dB, constant group delay and gain flatness over the frequency range set by the Federal Communications Commission (FCC) for UWB application. Satisfactory performance was obtained using FR4

Z. N. Low; J. H. Cheong; C. L. Law

2005-01-01

192

Amplify-and-Forward Cooperative Diversity for Green UWB-Based WBSNs  

PubMed Central

This paper proposes a novel green cooperative diversity technique based on suboptimal template-based ultra-wideband (UWB) wireless body sensor networks (WBSNs) using amplify-and-forward (AF) relays. In addition, it analyzes the bit-error-rate (BER) performance of the proposed nodes. The analysis is based on the moment-generating function (MGF) of the total signal-to-noise ratio (SNR) at the destination. It also provides an approximate value for the total SNR. The analysis studies the performance of equally correlated binary pulse position modulation (EC-BPPM) assuming the sinusoidal and square suboptimal template pulses. Numerical results are provided for the performance evaluation of optimal and suboptimal template-based nodes with and without relay cooperation. Results show that one relay node provides ~23?dB performance enhancement at 1e ? 3 BER, which mitigates the effect of the nondesirable non-line-of-sight (NLOS) links in WBSNs. PMID:24307880

2013-01-01

193

Joint Timing and Channel Estimation for Ultra-Wideband Signals  

NASA Astrophysics Data System (ADS)

This paper is concerned with timing synchronization of high rates UWB signals operating in a dense multipath environment, where access must tackle inter-frame interference (IFI), inter-symbol interference (ISI) and even multi-user interference (MUI). A training-based joint timing and channel estimation scheme is proposed, which is resilient to IFI, ISI, MUI and pulse distortion. A low-complexity detection scheme similar to transmit-reference (TR) scheme comes out as a by-product. For saving the training symbols, we further develop an extended decision-directed (DD) scheme. A lower bound on the probability of correct detection is derived which agrees well with the simulated result for moderate to high SNR values. The results show that the proposed algorithm achieves a significant performance gain in terms of mean square error and bit error rate in comparison to the “timing with dirty templates” (TDT) algorithms.

Liu, Tao; Zhu, Shihua

194

Research of all-optical ultra-wideband triplet signal source based on a single semiconductor optical amplifier  

NASA Astrophysics Data System (ADS)

A novel scheme for all-optical ultra-wideband triplet signal pulse generation based on the cross-gain modulation (XGM) in a single semiconductor optical amplifier (SOA) is demonstrated. In this scheme, only one optical source and one SOA are needed, so the configuration is simple. Due to only one wavelength is included in the generated triplet pulse, no time difference between output signal light and probe light is introduced during the transmission process. By using the software of Optisystem 7.0, the impacts of the input signal width, the optical power and the wavelength of the optical source on the generated triplet pulse are numerically simulated and studied. The results show that the proposed scheme has better triplet signal pulse when the input signal pulse width is larger, and it is insensitive to the wavelength change within a certain range.

Xue, Fei; Li, Pei-li; Zheng, Jia-jin; Wang, Li-li; Liang, Wei-kang

2013-07-01

195

Performance of multiple pulse multiple delay modulated UWB signals in a multiple access indoor wireless channel  

Microsoft Academic Search

In this paper, the performance of a two user UWB multiple access (UWB-MA) system based on multiple-pulse multiple-delay (MPMD) modulation scheme in an indoor wireless channel is evaluated by computer simulations. The indoor multipart propagation channel model used in this study is based on the modified statistical Saleh-Valenzuela model proposed by Foerester and Li from Intel. The simulation results indicate

Faranak Nekoogar; Farid Dowla

2003-01-01

196

All-optical binary phase-coded UWB signal generation using DWDM-based multi-channel frequency discriminator  

NASA Astrophysics Data System (ADS)

A simple all-optical binary phase-coded ultra-wideband (UWB) signal generation scheme only using a DWDM-based multi-channel optical frequency discriminator is proposed and demonstrated. In the proposed scheme, the CW lights emitted from a laser array are modulated in a phase modulator driven by electrical Gaussian pulses, and then are sent to a DWDM used as a multi-channel optical frequency discriminator, in which phase modulation to intensity modulation (PM-IM) conversions are performed, and by locating the phase-modulated light wavelengths at the positive or negative slopes of the DWDM transmission spectra, delaying and recombining each channel signal, binary phase-coded UWB codes are generated. We numerically demonstrate encode and decode process of binary phase-coded UWB signals with a code length of 4, operating at 625 Mbit/s. In addition, binary phase-coded UWB signal transmission in fiber link was also numerically investigated. Our proposed system has potential application in future multi-user UWB-over-fiber communication systems.

Tan, Long-Sheng; Wang, Fei; Ma, Huan; Hu, Qiang; Zhao, Xiao-Fang

2014-02-01

197

Ultra-wideband Location Authentication for Item Tracking  

SciTech Connect

International safeguards is increasingly utilizing unattended and remote monitoring methods to improve inspector efficiency and the timeliness of diversion detection. Item identification and tracking has been proposed as one unattended remote monitoring method, and a number of radio-frequency (RF) technologies have been proposed. When utilizing location information for verification purposes, strong assurance of the authenticity of the reported location is required, but most commercial RF systems are vulnerable to a variety of spoofing and relay attacks. ORNL has developed a distance bounding method that uses ultra-wideband technology to provide strong assurance of item location. This distance bounding approach can be coupled with strong symmetric key authentication methods to provide a fully authenticable tracking system that is resistant to both spoofing and relay attacks. This paper will discuss the overall problems associated with RF tracking including the common spoofing and relay attack scenarios, the ORNL distance bounding approach for authenticating location, and the potential applications for this technology.

Rowe, Nathan C [ORNL; Kuhn, Michael J [ORNL; Stinson, Brad J [ORNL; Holland, Stephen A [ORNL

2012-01-01

198

QUAD RIDGED HORN ANTENNA FOR UWB APPLICATIONS  

Microsoft Academic Search

Abstract—This paper describes a novel design of a dual-polarized ultra wideband horn antenna. Based on a VSWR ? 2.6, the bandwidth of the designed UWB horn antenna is from 8–18 GHz, most suitable for radar systems. A newcoaxial line to quadruple-ridged waveguide transition and a newtechnique for tapering the flared section of the horn is introduced to improve the return

Ramin Dehdasht-Heydari; Hamid Reza Hassani; Ali Reza Mallahzadeh

2008-01-01

199

Human body imaging by microwave UWB radar  

Microsoft Academic Search

This paper investigates the feasibility of human body imaging by means of microwave ultra-wideband (UWB) radar with a planar aperture. Its potential imaging capability is at first estimated by numerical simulation which demonstrates the dependence of cross-range resolution and side\\/grating lobe level on both the operational bandwidth and spatial sampling. Experimental results from 2-D synthetic aperture (SAR) measurements validate the

X. Zhuge; T. G. Savelyev; A. G. Yarovoy; L. P. Ligthart; J. Matuzas; B. Levitas

2008-01-01

200

Novel Compact Ultra-Wideband Bandpass Filter by Application of Short-Circuited Stubs and Stepped-Impedance-Resonator  

NASA Astrophysics Data System (ADS)

To realize the compact ultra-wideband (UWB) bandpass filters, a novel filter prototype with two short-circuited stubs loaded at both sides of a stepped-impedance resonator (SIR) via the parallel coupled lines is proposed based on a distributed filter synthesis theory. The equivalent circuit of this filter is established, while the corresponding 7-pole Chebyshev-type transfer function is derived for filter synthesis. Then, a distributed-circuit-based technique was presented to synthesize the elements' values of this filter. As an example, a FCC UWB filter with the fractional bandwidth (FWB) @ -10dB up to 110% was designed using the proposed prototype and then re-modeled by commercial microwave circuit simulator to verify the correctness and accuracy of the synthesis theory. Furthermore, in terms of EM simulator, the filter was further-optimized and experimentally-realized by using microstrip line. Good agreements between the measurement results and theoretical ones validate the effectiveness of our technique. In addition, compared with the conventional SIR-type UWB filter without short-circuited stubs, the new one significantly improves the selectivity and out-of-band characteristics (especially in lower one -45dB@1-2GHz) to satisfy the FCC's spectrum mask. The designed filter also exhibits very compact size, quite low insertion loss, steep skirts, flat group delay and the easily-fabricatable structure (the coupling gap dimension in this filter is 0.15mm) as well. Moreover, it should be noted that, in terms of the presented design technique, the proposed filter prototype can be also used to easily realize the UWB filters with other FBW even greater than 110%.

Chen, Chun-Ping; Ma, Zhewang; Anada, Tetsuo

201

Ultra-Wideband Bandpass Filter with Sharp Attenuation Slope Using Inter-Digital Finger Resonator and Parallel-Coupled Lines  

NASA Astrophysics Data System (ADS)

This paper presents an ultra-wideband (UWB) bandpass filter (BPF) with sharp attenuation slope characteristics. The circuit structure consists of an inter-digital finger resonator, parallel-coupled lines and phase matching line. The design of the bandwidth was described by using the even and odd mode characteristic impedances in the resonator structure. The parallel-coupled lines were also designed in the same manner. The parameters of the resonator and two parallel-coupled lines in combination as the BPF were then optimized by the simulation with HFSS. The designed BPF was experimentally fabricated and its measured performances showed the bandwidth from 3.6 to 10GHz with the 20dB outband rejection. For the U.S. UWB band design, the matching line was inserted between the two parallel-coupled lines. The matching at both band edges was then qualitatively analyzed on the smithchart. The HFSS simulation results of the structure realized the bandwidth from 3.1 to 10.6GHz with sharp attenuation slope characteristics for SWR < 2.0. The measurement results agree well with the simulation results.

Yasuzumi, Takenori; Omote, Yusuke; Uwano, Tomoki; Hashimoto, Osamu

202

A technique for the generation of customizable ultra-wideband pseudo-noise waveforms  

NASA Astrophysics Data System (ADS)

Noise excitation sources in radar systems have become increasingly useful in applications requiring wideband spectral responses and covertness. However, in applications requiring spectral controllability, traditional analog noise sources prove troublesome and require additional hardware such as sets of digital filters whose own spectral characteristics must also be accounted for. In an effort to reduce these issues and increase the applications of noise waveforms, a technique for generating a fully controllable pseudo-noise waveform is presented. This pseudo-noise waveform will be generated through the use of a multi-tone waveform. By randomizing the phase angles and setting the appropriate amplitudes to the individual tones, the result is a waveform whose temporal pattern resembles noise and frequency response is broadband. The capabilities of this digitally produced pseudo-noise multi-tone waveform is presented by optimization via a water-filling technique, thereby producing a flat spectral response for a user defined amplitude, effectively removing the spectral effects of the radar components. This optimized waveform is used to present methods for increasing signal to noise ratio (SNR) of cross-correlated responses of the waveform through the application of window functions to the waveform. As a whole, this paper showcases the ability to use this pseudo-noise multi-tone waveform for complete ultra-wideband (UWB) spectral control through water-filling and a method for increasing SNR of the cross correlated response of the transmitted and received radar waveform for a bandwidth of 2.5 GHz ranging from 2 to 4.5 GHz.

Vela, Russell; Erisman, David; Narayanan, Ram M.

2011-06-01

203

A 21pJ/pulse FCC Compliant UWB Pulse Generator Yousif Shamsa and Wouter A. Serdijn  

E-print Network

A 21pJ/pulse FCC Compliant UWB Pulse Generator Yousif Shamsa and Wouter A. Serdijn Electronics is presented. A 6th order elliptical filter approximation of the Federal Com- munications Commission (FCC, when the Federal Communications Commission (FCC) approved this technology for commercial applications

Serdijn, Wouter A.

204

Switchable optical UWB monocycle and doublet generation using a reconfigurable photonic microwave delay-line filter.  

PubMed

Optically switchable Ultra-Wideband (UWB) monocycle and doublet pulse generation using an optically reconfigurable photonic microwave delay-line filter is proposed and demonstrated. The microwave filter can be reconfigured as a two- or three-tap microwave filter with coefficients of (1, -1) or (1, -2, 1). The function of the two- or three-tap microwave filter is equivalent to an operation of a first- or second-order difference, which can be approximated as a first- or second-order derivative. When a Gaussian pulse is inputted to the two- or three-tap microwave delay-line filter, a Gaussian monocycle or doublet pulse is generated. The proposed photonic microwave delay-line filter is implemented using a polarization modulator (PolM), a length of polarization maintaining fiber (PMF), and a balanced photo-detector (BPD). In the experiment, Gaussian monocycle and doublet pulses with a fractional bandwidth of about 170% and 130% are generated. The switchability of the proposed UWB pulse generator in pulse shape and polarity is also experimentally demonstrated. PMID:19550747

Wang, Qing; Yao, Jianping

2007-10-29

205

Impulse Radio Ultra-Wideband Communication Over Free-Space Optical Links  

E-print Network

. The elements of the input Gaussian pulse train are first phase modulated by a high-speed electro-optical phase]. The UWB pulses are directly gener- ated in the optical domain by the use of a high-speed electro- optic to achieve very high data rates, however, due to the low power requirement and the severe multipath

Deliç, Hakan

206

Physical optics characterization of a THz time domain system: UWB leaky lens antenna vs. Austin switch  

Microsoft Academic Search

In this work we show that a THz time domain system based on photoconductive antennas can be improved by over one order of magnitude by using the Ultra-wideband (UWB) leaky lens antenna. The system has been analyzed by implementing a physical optics method to characterize radiated fields by a silicon lens.

N. Llombart; A. Neto; P. H. Siegel

2010-01-01

207

Adaptive and Cognitive UWB Radio and a Vision for Flexible Future Spectrum Management  

Microsoft Academic Search

The continuing intense debate on introduction of ultra wideband (UWB) communications has focused on concerns about interference into and by other communication systems, and resulted in much research into how to mitigate it. Adaptive techniques to mitigate interference are summarized. The definition and use of \\

Michael Sablatash

2007-01-01

208

75 FR 62476 - Ultra-Wideband Transmission Systems  

Federal Register 2010, 2011, 2012, 2013, 2014

...Systems proceeding and thus provides certainty for the continued development of UWB equipment, including ground penetrating radars for underground imaging, through wall imaging systems, short- range high capacity data links, and other applications....

2010-10-12

209

Group Delay in THz Spectroscopy with Ultra-Wideband Log-Spiral Antennae  

NASA Astrophysics Data System (ADS)

We report on the group delay observed in continuous-wave terahertz spectroscopy based on photomixing with phase-sensitive homodyne detection. We discuss the different contributions of the experimental setup to the phase difference ? ?( ?) between transmitter arm and receiver arm. A simple model based on three contributions yields a quantitative description of the overall behavior of ? ?( ?). Firstly, the optical path-length difference gives rise to a term linear in frequency ?. Secondly, the ultra-wideband log-spiral antennae effectively radiate and receive in a frequency-dependent active region, which in the most simple model is an annular area with a circumference equal to the wavelength. The corresponding term changes by roughly 6 ? between 100 GHz and 1 THz. The third contribution stems from the photomixer impedance. In contrast, the derivative ?? ?/ ? ? is dominated by the contribution of periodic modulations of ? ?( ?) caused by standing waves, e.g., in the photomixers' Si lenses. Furthermore, we discuss the Fourier-transformed spectra, which are equivalent to the waveform in a time-domain experiment. In the time domain, the group delay introduced by the log-spiral antennae gives rise to strongly chirped signals, in which low frequencies are delayed. Correcting for the contributions of antennae and photomixers yields sharp peaks or "pulses" and thus facilitates a time-domain-like analysis of our continuous-wave data.

Langenbach, M.; Roggenbuck, A.; Cámara Mayorga, I.; Deninger, A.; Thirunavukkuarasu, K.; Hemberger, J.; Grüninger, M.

2014-11-01

210

Cognitive Implementation of Chirp Waveform in UWB System  

NASA Astrophysics Data System (ADS)

Cognitive Radios (CR) can recognize the communication environment and switch its communication scheme to more efficiently and flexibly utilize the radio spectrum. The performance of ultra wideband (UWB) degrades if interference is not suppressed properly. We propose here a series of adaptive chirp waveforms in UWB systems. By designing waveform shaping of both linear chirp and non-linear cases, we avoid the estimated spectrum of the on-going applications without the necessity of notch filters, and thus reduce the system complexity. We evaluate system performance of the proposed scheme by simulations and verify that the proposed scheme is a candidate for cognitive UWB systems.

Shen, Hanbing; Zhang, Weihua; Kwak, Kyung Sup

211

Millimeter-Wave Ultra-Wideband Bandpass Filter Employing Dual-Mode Ring Resonators Fed by Step-Impedance Coupled Lines  

NASA Astrophysics Data System (ADS)

This paper presents a novel millimeter-wave ultra-wideband (UWB) bandpass filter (BPF) based on microstrip dual-mode rectangular ring resonators. In order to get strong coupling between the input/output line and the dual-mode ring resonators, a step-impedance parallel-coupled structure is adopted for the design of the filter. On the other hand, transmission zeros are produced by the dual-mode resonator. As a consequence, the filter has low insertion-loss in its passband, sharp attenuation in its lower and upper stopbands and very wide stopbands. As an example, a filter with two dual-mode ring resonators is designed and fabricated. The measured frequency property of the fabricated filter shows good agreement with the simulated response.

Cai, Peng; Ma, Zhewang; Kanzaki, Hitoshi; Zhang, Yong; Chen, Bin

2009-05-01

212

Physical Modeling and Template Design for UWB Channels with Per-Path Distortion  

Microsoft Academic Search

Recent experimental and physical modeling studies demonstrate that, as opposed to systems with smaller bandwidth, the ultra-wideband (UWB) channel exhibits frequency-dependent distortion of individual multipath components. This per-path distortion is particularly significant in outdoor UWB applications, where line-of-sight (LOS) or non-distorted reflected signals might not be available at the receiver (for example, in a canyon-like street). In these cases, the

L. Ma; A. Duel-Hallen; H. Hallen

2006-01-01

213

Ultra-Wideband Optical Modulation Spectrometer (OMS) Development  

NASA Technical Reports Server (NTRS)

The optical modulation spectrometer (OMS) is a novel, highly efficient, low mass backend for heterodyne receiver systems. Current and future heterodyne receiver systems operating at frequencies up to a few THz require broadband spectrometer backends to achieve spectral resolutions of R approximately 10(exp 5) to 10(exp 6) to carry out many important astronomical investigations. Among these are observations of broad emission and absorption lines from extra-galactic objects at high redshifts, spectral line surveys, and observations of planetary atmospheres. Many of these lines are pressure or velocity broadened with either large half-widths or line wings extending over several GHz. Current backend systems can cover the needed bandwidth only by combining the output of several spectrometers, each with typically up to 1 GHz bandwidth, or by combining several frequency-shifted spectra taken with a single spectrometer. An ultra-wideband optical modulation spectrometer with 10 - 40 GHz bandwidth will enable broadband ob- servations without the limitations and disadvantages of hybrid spectrometers. Spectrometers like the OMS will be important for both ground-based observatories and future space missions like the Single Aperture Far-Infrared Telescope (SAFIR) which might carry IR/submm array heterodyne receiver systems requiring a spectrometer for each array pixel. Small size, low mass and small power consumption are extremely important for space missions. This report summarizes the specifications developed for the OMS and lists already identified commercial parts. The report starts with a review of the principle of operation, then describes the most important components and their specifications which were derived from theory, and finishes with a conclusion and outlook.

Gardner, Jonathan (Technical Monitor); Tolls, Volker

2004-01-01

214

Ultra-wideband polarization conversion metasurfaces based on multiple plasmon resonances  

NASA Astrophysics Data System (ADS)

We propose to realize ultra-wideband polarization conversion metasurfaces in microwave regime through multiple plasmon resonances. An ultra-wideband polarization conversion metasurface is designed using a double-head arrow structure and is further demonstrated both numerically and experimentally. Four plasmon resonances are generated by electric and magnetic resonances, which lead to bandwidth expansion of cross-polarization reflection. The simulated results show that the maximum conversion efficiency is nearly 100% at the four plasmon resonance frequencies and a 1:4 3 dB bandwidth can be achieved for both normally incident x- and y-polarized waves. Experimental results agree well with simulation ones.

Chen, Hongya; Wang, Jiafu; Ma, Hua; Qu, Shaobo; Xu, Zhuo; Zhang, Anxue; Yan, Mingbao; Li, Yongfeng

2014-04-01

215

Design and development of a small compact ultra wideband antenna  

NASA Astrophysics Data System (ADS)

In this paper the design of a novel and compact U slot UWB printed monopole microstrip antenna of size 19.2 × 28.8 mm2 has been presented for wireless applications. The planar, small and thin UWB antenna design consists of a U slot radiator fed by a single 50? microstrip line with truncated ground plane is excited by a coaxial SMA connector. The simulations are done using the Ansoft High Frequency Structure Simulator (HFSS) software tool. The simulated results of impedance bandwidth are well supported by measurement. The measured group delay and radiation pattern results are also presented and performance of the antenna is analyzed/discussed.

Qurratulain; Chattoraj, Neela

2013-04-01

216

UWB Tracking Software Development  

NASA Technical Reports Server (NTRS)

An Ultra-Wideband (UWB) two-cluster Angle of Arrival (AOA) tracking prototype system is currently being developed and tested at NASA Johnson Space Center for space exploration applications. This talk discusses the software development efforts for this UWB two-cluster AOA tracking system. The role the software plays in this system is to take waveform data from two UWB radio receivers as an input, feed this input into an AOA tracking algorithm, and generate the target position as an output. The architecture of the software (Input/Output Interface and Algorithm Core) will be introduced in this talk. The development of this software has three phases. In Phase I, the software is mostly Matlab driven and calls C++ socket functions to provide the communication links to the radios. This is beneficial in the early stage when it is necessary to frequently test changes in the algorithm. Phase II of the development is to have the software mostly C++ driven and call a Matlab function for the AOA tracking algorithm. This is beneficial in order to send the tracking results to other systems and also to improve the tracking update rate of the system. The third phase is part of future work and is to have the software completely C++ driven with a graphics user interface. This software design enables the fine resolution tracking of the UWB two-cluster AOA tracking system.

Gross, Julia; Arndt, Dickey; Ngo, Phong; Phan, Chau; Dusl, John; Ni, Jianjun; Rafford, Melinda

2006-01-01

217

An Ultra-Wideband Amplifier MMIC for 3-10.6 GHz Wireless Applications with InGaP/GaAs HBT Technology  

NASA Astrophysics Data System (ADS)

An ultra-wideband amplifier MMIC has been demonstrated for the Ultra-Wide-Band (UWB) standard with InGaP/GaAs Heterojunction Bipolar Transistor (HBT) technology. The fabricated MMIC chip size is only 0.53 mm by 0.93mm. The amplifier MMIC includes all matching circuits on the chip. This amplifier MMIC is applicable to both a UWB low noise amplifier and a UWB transmitter amplifier by changing the collector current. The operating bias currents are 15 mA for a low noise amplifier and 30 mA for a transmitter amplifier. The collector bias voltage is 3.0 V. The MMIC as a transmitter amplifier exhibits a gain of 16 +/-1 dB and a third-order intercept point at the input (IIP3) of 0 dBm with 6.0 and 6.01 GHz signals with equal amplitude level. As a low noise amplifier, the MMIC exhibits a noise figure of less than 3.7 dB from 3.1 to 10.6 GHz.

Kurachi, Satoshi; Yoshimasu, Toshihiko; Liu, Haiwen; Chen, Jia; Shimamatsu, Yuichiro

218

Tightly-coupled GPS/UWB Integration  

NASA Astrophysics Data System (ADS)

Ultra-wideband (UWB) ranging radios, an emerging technology that offers precise, short distance range measurements are investigated as a method to augment carrier-phase GPS positioning. A commercially available UWB ranging system is used in a tightly-coupled GPS and UWB real-time kinematic (RTK) system. The performance of the tightly-coupled system is evaluated in static and kinematic testing. This work demonstrates that UWB errors can be successfully estimated in a real-time filter. The results of static testing show that the integrated solution provides better accuracy, better ability to resolve integer ambiguities and enhanced fixed ambiguity solution availability compared with GPS alone. In kinematic testing in a degraded GPS environment, sub-decimetre accuracy was maintained.

Macgougan, Glenn; O'Keefe, Kyle; Klukas, Richard

219

High-order UWB pulses scheme to generate multilevel modulation formats based on incoherent optical sources.  

PubMed

We present a high-order UWB pulses generator based on a microwave photonic filter which provides a set of positive and negative samples by using the slicing of an incoherent optical source and the phase inversion in a Mach-Zehnder modulator. The simple scalability and high reconfigurability of the system permit a better accomplishment of the FCC requirements. Moreover, the proposed scheme permits an easy adaptation to pulse amplitude modulation, bi phase modulation, pulse shape modulation and pulse position modulation. The flexibility of the scheme for being adaptable to multilevel modulation formats permits to increase the transmission bit rate by using hybrid modulation formats. PMID:24514405

Bolea, Mario; Mora, José; Ortega, Beatriz; Capmany, José

2013-11-18

220

A high-speed circuit architecture for IR-UWB transmission of fast-scan cyclic voltammetry in 0.35 ?m CMOS.  

PubMed

This paper reports on the design of a high-speed circuit for impulse radio ultra-wideband (IR-UWB) transmission of 16-channel neurochemical activity recorded using 300-V/s fast-scan cyclic voltammetry (FSCV). Simulated in a low-cost 0.35-?m standard complementary metal-oxide-semiconductor (CMOS) technology, the circuit generates 3(rd)-derivative Gaussian pulses with sub-nanosecond duration, which are highpass filtered externally using a 4(th)-order Butterworth filter before feeding to an off-chip UWB antenna. The power spectral density (PSD) achieves a peak emission frequency of 4.6 GHz with a 2.3-GHz bandwidth (-10 dB), and is fully compliant with the UWB emission mask. The energy efficiency in pulse generation is 161.7 pJ/pulse that leads to a power consumption of 4.85 mW from 3.3 V for a data rate of 15 Mbps, when two pulses are used to transmit a single data bit. PMID:21096381

Zamani, Hamidreza; Mohseni, Pedram

2010-01-01

221

Software defined radio channel simulator for wireless communications: Demonstrations of the hardware reconfiguration using DSRC and UWB channels  

Microsoft Academic Search

The software defined radio (SDR) channel simulator is designed and implemented in the FPGA for various wireless communication systems. The dedicated short range communications (DSRC) and ultra-wideband (UWB) channels are carried out to observe the characteristics of multi-path fading channels and validate the correctness of the SDR channel simulator. The hardware reconfiguration of the fading channel weighting generator circuit module

Jeich Mar; Chi-Cheng Kuo; You-Rong Lin; Ti-Han Lung

2009-01-01

222

Approaching vehicle alert system for pedestrians using UWB impulse radio  

Microsoft Academic Search

Accidents between battery-operated vehicles and pedestrians are expected to increase as electric vehicles (EV) or plug-in hybrid vehicles (PHV) are widely used in near future because of small ambient noise of EV\\/PHV. To prevent such accidents, a portable alert system for pedestrians to detect approaching vehicle is proposed in this paper. The alert system exploits ultra-wideband impulse radio (UWB-IR) for

Keiichi Nakamura; Hisanori Matsumoto; S. Kobayashi; N. Koshizuka; K. Sakamura

2010-01-01

223

A Synchronization Design for UWB-Based Wireless Multimedia Systems  

Microsoft Academic Search

Multi-band orthogonal frequency-division multiplexing (MB-OFDM) ultra-wideband (UWB) technology offers large throughput, low latency and has been adopted in wireless audio\\/video (AV) network products. The complexity and power consumption, however, are still major hurdles for the technology to be widely adopted. In this paper, we propose a unified synchronizer design targeted for MB-OFDM transceiver that achieves high performance with low implementation

Zhenzhen Ye; Chunjie Duan; Philip V. Orlik; Jinyun Zhang; Alhussein A. Abouzeid

2010-01-01

224

On optimal data detection for UWB transmitted reference systems  

Microsoft Academic Search

Transmitted reference (TR) modulation schemes, initially proposed for spread-spectrum systems in the 1920's have regained popularity in the context of ultra-wideband (UWB) communications, where accurate channel estimation is a challenging task. In the conventional TR approach, a reference signal (without data modulation) is received and employed in a correlator receiver for data modulated signals. By exploiting the statistics of the

Stefan Franz; Urbashi Mitra

2003-01-01

225

Studies of Scattering, Reflectivity, and Transmitivity in WBAN Channel: Feasibility of Using UWB  

PubMed Central

The Wireless Personal Area Network (WPAN) is one of the fledging paradigms that the next generation of wireless systems is sprouting towards. Among them, a more specific category is the Wireless Body Area Network (WBAN) used for health monitoring. On the other hand, Ultra-Wideband (UWB) comes with a number of desirable features at the physical layer for wireless communications. One big challenge in adoption of UWB in WBAN is the fact that signals get attenuated exponentially. Due to the intrinsic structural complexity in human body, electromagnetic waves show a profound variation during propagation through it. The reflection and transmission coefficients of human body are highly dependent upon the dielectric constants as well as upon the frequency. The difference in structural materials such as fat, muscles and blood essentially makes electromagnetic wave attenuation to be different along the way. Thus, a complete characterization of body channel is a challenging task. The connection between attenuation and frequency of the signal makes the investigation of UWB in WBAN an interesting proposition. In this paper, we study analytically the impact of body channels on electromagnetic signal propagation with reference to UWB. In the process, scattering, reflectivity and transmitivity have been addressed with analysis of approximate layer-wise modeling, and with numerical depictions. Pulses with Gaussian profile have been employed in our analysis. It shows that, under reasonable practical approximations, the human body channel can be modeled in layers so as to have the effects of total reflections or total transmissions in certain frequency bands. This could help decide such design issues as antenna characteristics of implant devices for WBAN employing UWB. PMID:22219673

Kabir, Md. Humaun; Ashrafuzzaman, Kazi; Chowdhury, M. Sanaullah; Kwak, Kyung Sup

2010-01-01

226

CPW-Fed Quasi-Magnetic Printed Antenna for Ultra-Wideband Applications  

Microsoft Academic Search

An optimized coplanar waveguide fed quasimagnetic printed antenna for ultra wideband applications is described. A parameter study, motivated by a design procedure, allowed a substantial increase in the return-loss operational bandwidth. The numerically predicted performance was validated by means of physical measurements of fabricated samples. The measured radiation patterns of the antenna demonstrated its adequate radiation characteristics. The feed radiation

F. Muge Tanyer-Tigrek; Dani P. Tran; I. E. Lager; Leonardus P. Ligthart

2009-01-01

227

Investigation on ultra-wideband printed circular monopole antenna with frequency-notched  

Microsoft Academic Search

This paper presents a novel design of a printed circular monopole antenna for ultra-wideband applications. It consists of a circular patch with an arc slot notched, which intends to obtain frequency notched for WLAN. To broaden the bandwidth and shorten the width of the substrate, a truncated ground plane is introduced. Thus, the width of the substrate is sharply shortened

Zhantao Yang; Li Li; Huazhi Wang

2008-01-01

228

Fingerprinting Localization based on Neural Networks and Ultra-wideband signals  

E-print Network

Fingerprinting Localization based on Neural Networks and Ultra-wideband signals Lei Yu, Mohamed Abstract--Fingerprinting techniques have been proved as an effective techniques for determining (RSS) are subject to big positioning errors. In this paper, a fingerprinting based localization

Paris-Sud XI, Université de

229

All-optical binary phase-coded UWB signal generation for multi-user UWB communications.  

PubMed

An all-optical incoherent scheme for generation of binary phase-coded ultra-wideband (UWB) signals is proposed and experimentally demonstrated. The binary phase coding is performed based on all-optical phase modulation in a semiconductor optical amplifier (SOA) and phase modulation to intensity modulation (PM-IM) conversion in a fiber delay interferometer (DI) that serves as a multichannel frequency discriminator. By locating the phase-modulated light waves at the positive and negative slopes of the DI transmission spectra, binary phase encoded UWB codes (0 and ?) are generated. We also experimentally demonstrate a bipolar UWB coding system with a code length of 4, operating at 1.25 Gb/s. And the decoding is analyzed as well. Our proposed system has potential application in future high-speed UWB impulse radio over optical fiber access networks. PMID:21643312

Dong, Jianji; Yu, Yuan; Zhang, Yin; Li, Xiang; Huang, Dexiu; Zhang, Xinliang

2011-05-23

230

UWB Tracking System Design for Free-Flyers  

NASA Technical Reports Server (NTRS)

This paper discusses an ultra-wideband (UWB) tracking system design effort for Mini-AERCam (Autonomous Extra-vehicular Robotic Camera), a free-flying video camera system under development at NASA Johnson Space Center for aid in surveillance around the International Space Station (ISS). UWB technology is exploited to implement the tracking system due to its properties, such as high data rate, fine time resolution, and low power spectral density. A system design using commercially available UWB products is proposed. A tracking algorithm TDOA (Time Difference of Arrival) that operates cooperatively with the UWB system is developed in this research effort. Matlab simulations show that the tracking algorithm can achieve fine tracking resolution with low noise TDOA data. Lab experiments demonstrate the UWB tracking capability with fine resolution.

Ni, Jianjun; Arndt, Dickey; Phan, Chan; Ngo, Phong; Gross, Julia; Dusl, John

2004-01-01

231

Millimeter-wave silicon-based ultra-wideband automotive radar transceivers  

NASA Astrophysics Data System (ADS)

Since the invention of the integrated circuit, the semiconductor industry has revolutionized the world in ways no one had ever anticipated. With the advent of silicon technologies, consumer electronics became light-weight and affordable and paved the way for an Information-Communication-Entertainment age. While silicon almost completely replaced compound semiconductors from these markets, it has been unable to compete in areas with more stringent requirements due to technology limitations. One of these areas is automotive radar sensors, which will enable next-generation collision-warning systems in automobiles. A low-cost implementation is absolutely essential for widespread use of these systems, which leads us to the subject of this dissertation---silicon-based solutions for automotive radars. This dissertation presents architectures and design techniques for mm-wave automotive radar transceivers. Several fully-integrated transceivers and receivers operating at 22-29 GHz and 77-81 GHz are demonstrated in both CMOS and SiGe BiCMOS technologies. Excellent performance is achieved indicating the suitability of silicon technologies for automotive radar sensors. The first CMOS 22-29-GHz pulse-radar receiver front-end for ultra-wideband radars is presented. The chip includes a low noise amplifier, I/Q mixers, quadrature voltage-controlled oscillators, pulse formers and variable-gain amplifiers. Fabricated in 0.18-mum CMOS, the receiver achieves a conversion gain of 35-38.1 dB and a noise figure of 5.5-7.4 dB. Integration of multi-mode multi-band transceivers on a single chip will enable next-generation low-cost automotive radar sensors. Two highly-integrated silicon ICs are designed in a 0.18-mum BiCMOS technology. These designs are also the first reported demonstrations of mm-wave circuits with high-speed digital circuits on the same chip. The first mm-wave dual-band frequency synthesizer and transceiver, operating in the 24-GHz and 77-GHz bands, are demonstrated. All circuits except the oscillators are shared between the two bands. A multi-functional injection-locked circuit is used after the oscillators to reconfigure the division ratio inside the phase-locked loop. The synthesizer is suitable for integration in automotive radar transceivers and heterodyne receivers for 94-GHz imaging applications. The transceiver chip includes a dual-band low noise amplifier, a shared downconversion chain, dual-band pulse formers, power amplifiers, a dual-band frequency synthesizer and a high-speed programmable baseband pulse generator. Radar functionality is demonstrated using loopback measurements.

Jain, Vipul

232

UWB micro-doppler radar for human gait analysis using joint range-time-frequency representation  

NASA Astrophysics Data System (ADS)

In this paper, we present a novel, standalone ultra wideband (UWB) micro-Doppler radar sensor that goes beyond simple range or micro-Doppler detection to combined range-time-Doppler frequency analysis. Moreover, it can monitor more than one human object in both line-of-sight (LOS) and through wall scenarios, thus have full human objects tracking capabilities. The unique radar design is based on narrow pulse transceiver, high speed data acquisition module, and wideband antenna array. For advanced radar post-data processing, joint range-time-frequency representation has been performed. Characteristics of human walking activity have been analyzed using the radar sensor by precisely tracking the radar object and acquiring range-time-Doppler information simultaneously. The UWB micro-Doppler radar prototype is capable of detecting Doppler frequency range from -180 Hz to +180 Hz, which allows a maximum target velocity of 9 m/s. The developed radar sensor can also be extended for many other applications, such as respiration and heartbeat detection of trapped survivors under building debris.

Wang, Yazhou; Fathy, Aly E.

2013-05-01

233

Research and design on ultra-wideband dielectric hemispheric lens loaded quad-ridged horn antenna  

Microsoft Academic Search

Based on the ultra-wideband ridged horn antenna theory in communication system, a new quad-ridged horn antenna with a lens is described in this paper, which consists of a quad-ridged horn and a dielectric hemispheric lens. By simulation and optimization with CST MWS software which is based on the finite integration technique, a dual polarization dielectric lens loaded quad-ridged horn antenna

Jinghui Qiu; Ying Suo; Wei Li

2007-01-01

234

Ultra-wideband, zero visual signature RF vest antenna for man-portable radios  

Microsoft Academic Search

This paper presents the recent research of the COMbat Wear INtegration (COMWIN) RF vest antenna initially presented at MILCOM2000. This version of the ultra-wideband VHF\\/UHF (30 MHz to 500 MHz) vest antenna, designated as MK-III, is integrated into the existing dismounted marine\\/soldier kevlar flak vest and has no visual signature. This antenna is one of the three COMWIN antennas developed

Jovan E. Lebaric; Richard W. Adler; Matthew E. Limbert

2001-01-01

235

Fully integrated microwave reflectometers in multi-layer microstrip-slot technology for ultra wideband applications  

Microsoft Academic Search

This paper presents the design of compact fully integrated six-port reflectometers, which, from scalar power measurements, are capable to determine the complex reflection coefficient over an ultra wide frequency band of 3.1 to 10.6 GHz. These devices are formed by multi-layer microstrip\\/slot couplers and power dividers that are assembled without vias or wire cross-overs. An ultra wideband operation of these

M. E. Bialkowski; N. Seman; M. S. Leong; S. P. Yeo

2008-01-01

236

A Low-Power Ultra-Wideband CMOS True RMS Power Detector  

Microsoft Academic Search

This paper introduces a low-power ultra-wideband true root-mean-square power detector with a 0.13-mum CMOS process operating from 125 MHz to 8.5 GHz. The detector utilizes the MOS transistor's square-law characteristic in the strong inversion region to obtain the power information of the input RF signal, and its exponential characteristic in the weak inversion region to realize the linear-in-decibel output. Measured

Yijun Zhou; Michael Yan-Wah Chia

2008-01-01

237

An ultra-wideband vertical transition from microstrip to stripline in PCB technology  

Microsoft Academic Search

An ultra-wideband transition from microstrip to stripline in PCB technology is presented applying only through via holes for simple fabrication. The design is optimized using full-wave EM simulations. A prototype is manufactured and measured achieving a return loss better than 8.7dB and an insertion loss better than 1.2 dB in the FCC frequency range. A meander-shaped delay line in stripline

Mario Leib; Michael Mirbach; Wolfgang Menzel

2010-01-01

238

Short-Range Wireless Communications for Next-Generation Networks: UWB, 60 GHz Millimeter-Wave WPAN, And ZigBee  

Microsoft Academic Search

This article presents standardization, regulation, and development issues associated with short-range wireless technologies for next-generation personal area networks (PAN). Ultra-wideband (UWB) and 60 GHz millimeter-wave communication technologies promise unprecedented short-range broadband wireless communication and are the harbingers of multigigabit wireless networks. Despite the huge potential for PAN, standardization and global spectrum regulations challenge the success of UWB. On the other

Theordore Rappaport

2007-01-01

239

UWB Technology and Applications on Space Exploration  

NASA Technical Reports Server (NTRS)

Ultra-wideband (UWB), also known as impulse or carrier-free radio technology, is one promising new technology. In February 2002, the Federal Communications Commission (FCC) approved the deployment of this technology. It is increasingly recognized that UWB technology holds great potential to provide significant benefits in many terrestrial and space applications such as precise positioning/tracking and high data rate mobile wireless communications. This talk presents an introduction to UWB technology and some applications on space exploration. UWB is characterized by several uniquely attractive features, such as low impact on other RF systems due to its extremely low power spectral densities, immunity to interference from narrow band RF systems due to its ultra-wide bandwidth, multipath immunity to fading due to ample multipath diversity, capable of precise positioning due to fine time resolution, capable of high data rate multi-channel performance. The related FCC regulations, IEEE standardization efforts and industry activities also will be addressed in this talk. For space applications, some projects currently under development at NASA Johnson Space Center will be introduced. These include the UWB integrated communication and tracking system for Lunar/Mars rover and astronauts, UWB-RFID ISS inventory tracking, and UWB-TDOA close-in high resolution tracking for potential applications on robonaut.

Ngo, Phong; Phan, Chau; Gross, Julia; Dusl, John; Ni, Jianjun; Rafford, Melinda

2006-01-01

240

OPTIMIZED ULTRA-WIDEBAND RADIATION OF DIPOLE ANTENNAS WITH TRIANGLE  

E-print Network

, including pulsed antennas. These generic problems have been widely explored through full-wave numerical electromagnetic solvers, the E- and K-pulse signal processing techniques, and other fashions. Previous work often mainly on signal processing like E- and K-pulse techniques are not well suited for direct implementation

Southern California, University of

241

A Long-Range UWB Channel Sounding System Exploiting UWB over Fibre Technology  

NASA Astrophysics Data System (ADS)

This study presents the design and realisation of an innovative ultra-wideband over fibre vector network analyser channel sounder for channel measurements. This technique exploits the low insertion loss and low dispersion penalty of an electro-absorption modulator and achieves good performance in terms of UWB transmission with very low power. Experimental results demonstrate that this technique achieves high-quality UWB signal distribution up to 20 GHz with the current equipment. A link budget for long distance channel measurements is analysed to investigate the expected received power levels, in order to identify a suitable power amplifier for the distance of 100 m. The system performance confirmed by conducting an indoor line-of-sight UWB measurement in a dense multipath environment. Channel parameters are reported and the system is shown to be suitable for point-to-point characterisation, synthetic aperture and multiple antenna measurements.

Kavatjikidis, A.; Edwards, D. J.; Stevens, C. J.

242

Novel UWB Bandpass Filter Using CPW-to-Microstrip Transition Structure  

NASA Astrophysics Data System (ADS)

A novel bandpass filter (BPF) for an ultra-wideband (UWB) system is proposed in this letter. The BPF consists of four coplanar stripline (CPS)-to-microstrip transitions. Each transition is employed for broad electromagnetic (EM) coupling between a short-circuited CPS and an open-circuited microstrip line. The equivalent circuit model of the proposed geometry is derived and utilized in the impedance and mode matching analysis. Measured results show good agreement with the analysis and simulated ones.

Lee, Tae-Hak; Baik, Jung-Woo; Pyo, Seongmin; Kim, Young-Sik

243

A New Compact Ultra Wide Band (UWB) Planar Antenna using Glass as Substrate  

Microsoft Academic Search

In this paper, we present a new planar waveguide-fed ultra wideband (UWB) antenna. This antenna is designed for 50 ? feed on a loss less glass as a substrate. The impedance bandwidth with VSWR < 2 is from about 4.4 GHz to more than 12 GHz in simulation results but from 3.8 GHz to about 11.5 GHz in measurement. This

S. A. Hosseini; Z. Atlasbaf; K. Forooraghi

2008-01-01

244

Coexistence Between DS-UWB and MB-OFDM: Analysis and Interference Mitigation  

Microsoft Academic Search

Ultra wideband (UWB) technology is one of the promising solutions for future short-range communication which has recently been receiving increasing attention by many researchers. So far, two standards have been proposed to the IEEE 802.15.3a task group (TG3a) as high-speed physical technologies for next-generation wireless personal area networks (WPAN). These standards are based on multiband orthogonal frequency division multiplexing (MB-OFDM)

Abolfazl Mehbodniya; Sonia Aïssa

2007-01-01

245

Modeling and Mitigation of Narrowband Interference for Transmitted-Reference UWB Systems  

Microsoft Academic Search

Transmitted-reference ultra-wideband (TR-UWB) systems, in conjunction with autocorrelation-receivers (AcR), can collect all energy of the multipath channel response at low complexity. Unfortunately the AcR front-end also collects the energy of narrowband interference (NBI) signals, which severely degrades its performance. We present an elaborate statistical analysis of the NBI for a multichannel AcR front-end. Our results show specific correlation properties, which

Yohannes D. Alemseged; Klaus Witrisal

2007-01-01

246

Fully integrated distributed power amplifier in CMOS technology, optimized for UWB transmitters  

Microsoft Academic Search

A power amplifier (PA) using the distributed amplifier technique for the ultra wideband (UWB) standard is presented. The amplifier is fabricated in a standard 0.13 ?m CMOS technology and comes with on-chip biasing circuitry and a non-distributed input stage. Measurement results are given for a chip-on-board module to take any influence of product assembly into account. It achieves a transmission

Christian Grewing; Kay Winterberg; Stefan van Waasen; Martin Friedrich; Giuseppe Li Puma; A. Wiesbauer; C. Sandner

2004-01-01

247

Prototype ultra wideband-based wireless body area network--consideration of CAP and CFP slot allocation during human walking motion.  

PubMed

This paper presents an experimental evaluation of communication during human walking motion, using the medium access control (MAC) evaluation system for a prototype ultra-wideband (UWB) based wireless body area network for suitable MAC parameter settings for data transmission. Its physical layer and MAC specifications are based on the draft standard in IEEE802.15.6. This paper studies the effects of the number of retransmissions and the number of commands of GTS (guaranteed time slot) request packets in the CAP (contention access period) during human walking motion by varying the number of sensor nodes or the number of CFP (contention free period) slots in the superframe. The experiments were performed in an anechoic chamber. The number of packets received is decreased by packet loss caused by human walking motion in the case where 2 slots are set for CFP, regardless of the number of nodes, and this materially decreases the total number of packets received. The number of retransmissions and the GTS request commands increase according to increases in the number of nodes, largely reflecting the effects of the number of CFP slots in the case where 4 nodes are attached. In the cases where 2 or 3 nodes are attached and 4 slots are set for CFP, the packet transmission rate is more than 95%. In the case where 4 nodes are attached and 6 slots are set for CFP, the packet transmission rate is reduced to 88% at best. PMID:23366429

Takei, Yuichiro; Katsuta, Hiroki; Takizawa, Kenichi; Ikegami, Tetsushi; Hamaguchi, Kiyoshi

2012-01-01

248

Negative refractive index material-inspired 90-deg electrically tilted ultra wideband resonator  

NASA Astrophysics Data System (ADS)

A negative refractive index material loaded patch antenna is proposed for ultra wideband applications. The wideband operation has been achieved by creating a defected ground plane with a CNC shaped split ring resonator. The defected ground plane CNC resonator also exhibits a 90-deg electrical tilt. Two additional slots are engineered in the patch antenna for further bandwidth enhancement. A -10 dB bandwidth with an order of 57.89% has been achieved with a peak gain of 5.37 dBi at a 5.5 GHz resonant frequency. Measured results demonstrate good agreement with simulated results.

Upadhyaya, Trushit K.; Kosta, Shiv Prasad; Jyoti, Rajeev; Palandoken, Merih

2014-10-01

249

Distance bounded energy detecting ultra-wideband impulse radio secure protocol.  

PubMed

We present a demonstration of a novel protocol for secure transmissions on a Ultra-wideband impulse radio that includes distance bounding. Distance bounding requires radios to be within a certain radius to communicate. This new protocol can be used in body area networks for medical devices where security is imperative. Many current wireless medical devices were not designed with security as a priority including devices that can be life threatening if controlled by a hacker. This protocol provides multiple levels of security including encryption and a distance bounding test to prevent long distance attacks. PMID:25571513

Hedin, Daniel S; Kollmann, Daniel T; Gibson, Paul L; Riehle, Timothy H; Seifert, Gregory J

2014-08-01

250

Chaotic ultra-wideband radio generator based on an optoelectronic oscillator with a built-in microwave photonic filter.  

PubMed

We induce a microwave photonic bandpass filter into an optoelectronic oscillator to generate a chaotic ultra-wideband signal in both the optical and electrical domain. The theoretical analysis and numerical simulation indicate that this system is capable of generating band-limited high-dimensional chaos. Experimental results coincide well with the theoretical prediction and show that the power spectrum of the generated chaotic signal basically meets the Federal Communications Commission indoor mask. The generated chaotic carrier is further intensity modulated by a 10 MHz square wave, and the waveform of the output ultra-wideband signal is measured for demonstrating the chaotic on-off keying modulation. PMID:22614596

Wang, Li Xian; Zhu, Ning Hua; Zheng, Jian Yu; Liu, Jian Guo; Li, Wei

2012-05-20

251

Accurate TOA-Based UWB Localization System in Coal Mine Based on WSN  

NASA Astrophysics Data System (ADS)

Over the last years, there has been a great deal of interest in Ultra Wideband (UWB) wireless communication and Wireless Sensor Networks(WSN), especially following the proposing of the internet of things by the MIT (Massachusetts Institute of Technology) in 1999, hich is also result in an increasing research on UWB and WSN applications. This article mainly introduced the accurate UWB Localization System based on WSN in coal mine. Firstly, we briefly introduced UWB and WSN Localization technology. Secondly, the advantages and disadvantages of the previous personnel localization technology in coal mine was analyzed and contrasted, and then the suitable personnel localization system in coal mine based on UWB signal and TOA estimate positioning scheme are presented. At last the rationality and feasibility of this scheme was proved through the simulation results.

Cheng, Guangliang

252

Ultra-Wideband GPR Imaging of the Vaucluse Karst Aquifer  

NASA Astrophysics Data System (ADS)

In this paper, we present the validation of an Ultra Wide band measurement system which is the first experimental step of the French MAXWELL Research Project devoted to the survey of the karst aquifer located in the Vaucluse in Provence. This radar system employs Exponentially Tapered Slot Antennas (ETSA), with a usable bandwidth from 100 MHz to 2.5 GHz. The antenna is driven by a .01- 26.5 GHz Agilent vector network analyzer (VNA), with a noise floor of -120dB under test conditions and a noise floor of -100 dB in a field setting. A synthetic pulse is applied to the antenna by using a classical step frequency sweeping. The recorded amplitudes and phases of the reflection coefficient (S11 parameter) are filtered and inverse Fourier transformed to obtain the time-domain data. In principal, due to the flat radiation characteristic of the frequency generator, appropriate synthetic pulses can be generated for analysis. The advantages of this approach are mainly, 1) a large depth resolution due to increased bandwidth, 2) a wider dynamic range for detection of weak late underground echoes, 3) a low signal distortion due to absence of pulse deconvolution post-processing. The foregoing system was deployed inside a tunnel in the Low-Noise Underground Laboratory (LSBB) located in Rustrel (France) which allows the use of low power radiation. Minimization of noise interference was accomplished by : 1) using low noise and low-loss cables, 2) using a PVC structure covered with absorbers to shield the ETSA from unwanted tunnel wall reflections and from radiation from the vector network analyzer, 3) an effective calibration of long cables to the antenna connector with careful cable unwinding to reduce phase errors, 4) a power level fixed at 8 dBm in the frequency band of interest to avoid distortion in the mixer of the VNA. Monostatic or multistatic data, were collected by moving manually the antennas along the PVC frame, in 5 cm increments over a length of 6 m. Both parallel and perpendicular polarizations were recorded. Data were obtained from 150 MHz to 2 GHz to reduce any reflections from the connection to the analyzer. Time sections were then processed after an inverse Fourier transform. To validate our results (from a geophysics point of view), reference data were also collected using 100, 250 and 500 MHz RAMAC GPR systems. Results are very promising especially regarding the resolution of the images, depth penetration and low emitting power. In future experiments, our approach could be still improved by using shorter cables, high directive antennas and absorbers to reduce coupling in multistatic configurations.

Dauvignac, J.; Fortino, N.; Sénéchal, G.; Cresp, A.; Yedlin, M.; Gaffet, S.; Rousset, D.; Pichot, C.

2008-12-01

253

Hybrid UWB and WiMAX radio-over-multi-mode fibre for in-building optical networks  

Microsoft Academic Search

In this paper the use of hybrid WiMedia-defined ultra-wideband (UWB) and IEEE 802.16d WiMAX radio-over-fibre is proposed and experimentally demonstrated for multi-mode based in-building optical networks with the advantage of great immunity to optical transmission impairments. In the proposed approach, spectral coexistence of both signals must be achieved with negligible mutual interference. The experimental study performed addressed an indoor configuration

R. Llorente J Perez

2014-01-01

254

Ultra-Wideband Radar Measurements Over Bare and Snow-Covered Saline Ice S. Gogineniand P. Kanagaratnam  

E-print Network

Ultra-Wideband Radar Measurements Over Bare and Snow-Covered Saline Ice S. Gogineniand P. Kanagaratnam Radar Systems & Remote Sensing Laboratory University of Kansas 2291 Irving Hill Rd., Lawrence, KS-We developed an tiltra-wideband radar operating over frequencies from 500 MHz to 18 Ghz and used

Kansas, University of

255

Generation and distribution of UWB pulse signals by use of optical phase modulation and PM-IM conversions  

NASA Astrophysics Data System (ADS)

In this paper, we present two approaches to generating and distributing FCC-regulated UltraWideBand (UWB) pulse signals in the optical domain, based on optical phase modulation. In the first approach, an electrical Gaussian pulse train is applied to modulate the phase of an optical carrier using an electrooptic phase modulator. A 25-km single-mode fiber link is then used to realize PM-IM conversion which has a frequency response equivalent to a microwave bandpass filter. When the Gaussian pulse train is distributed over the 25-km fiber, the Gaussian pulses are then shaped into doublet pulses at the receiver front-end. Therefore, the UWB pulses are not generated but also distributed over optical fiber. In the second approach, instead of using an electrooptic phase modulator, optical phase modulation is implemented in the optical domain based on cross phase modulation in a nonlinear fiber. The PM-IM conversion is then achieved by use of a fiber Bragg grating that serves as a frequency discriminator. Electrical monocycle and doublet pulses are obtained at the output of the photodetector. Experimental results for both approaches are presented and discussed. The use of the second configuration to implement pulse on-off, polarity and shape modulation in the optical domain is also discussed.

Zeng, Fei; Yao, Jianping

2006-09-01

256

Pulse-Based Radar Imaging Using a Genetic Optimization Approach for Echo Separation  

Microsoft Academic Search

This paper describes a novel 3-D ultra-wideband (UWB) imaging technique with the aim of detecting, classifying, and imaging water pipes located inside walls. The target under test was chosen in such a way that the echoes of the front side of the wall and of the water pipes overlap making it impossible to distinguish between them in the raw data.

Sebastian Hantscher; Christian G. Diskus

2009-01-01

257

A 2.4 GHz Differential Wavelet Generator in 0.18 ?m Complementary Metal-Oxide-Semiconductor for 1.4 Gbps Ultra-Wideband Impulse Radio in Wireless Inter/Intra-Chip Data Communication  

NASA Astrophysics Data System (ADS)

Ultra-wideband impulse based radio systems use Gaussian monocycle pulses as transmitted signals at the transmitting end and as template signals at the receiving end. In this paper we present a new fully integrated differential Gaussian monocycle pulse generator in 0.18 ?m complementary metal-oxide-semiconductor (CMOS) technology. Here the Gaussian monocycle pulse is generated from triangular shaped pulse by a single differentiator circuit and it is then converted into differential form by using a single input to dual output amplifier. The developed circuit occupies a small area of 0.06 mm2 and consumes a total power of 44 mW at 1.8 V. The transmission of the generated differential Gaussian monocycle pulse at a rate of 1.4 Gbps through integrated dipole antenna in the same Si-substrate for intrachip communication in future ultralarge scale integrated circuit (ULSI) is verified by simulation and results are presented here.

Saha, Pran Kanai; Sasaki, Nobuo; Kimoto, Kentaro; Kikkawa, Takamaro

2006-04-01

258

S - C - L triple wavelength superluminescent source based on an ultra-wideband SOA and FBGs  

NASA Astrophysics Data System (ADS)

We propose and demonstrate a wide-band semiconductor optical amplifier (SOA) based triple-wavelength superluminescent source with the output in the S-, C- and L-band regions. The proposed systems uses an ultra-wideband SOA with an amplification range from 1440 to 1620 nm as the linear gain medium. Three fibre Bragg gratings (FBGs) with centre wavelengths of 1500, 1540 and 1580 nm are used to generate the lasing wavelengths in the S-, Cand L-bands respectively, while a variable optical attenuator is used to finely balance the optical powers of the lasing wavelengths. The ultra-wideband SOA generates an amplified spontaneous emission (ASE) spectrum with a peak power of -33 dBm at the highest SOA drive current, and also demonstrates a down-shift in the centre wavelength of the generated spectrum due to the spatial distribution of the carrier densities. The S-band wavelength is the dominant wavelength at high drive currents, with an output power of -6 dBm as compared to the C- and L-bands, which only have powers of -11 and -10 dBm, respectively. All wavelengths have a high average signal-to-noise ratio more than 60 dB at the highest drive current of 390 mA, and the system also shows a high degree of stability, with power fluctuations of less than 3 dB within 70 min. The proposed system can find many applications where a wide-band and stable laser source is crucial, such as in communications and sensing.

Ahmad, H.; Zulkifli, M. Z.; Hassan, N. A.; Muhammad, F. D.; Harun, S. W.

2013-10-01

259

Two-Stage Acquisition in Time-Hopping Impulse Radio Systems for UWB Communications  

Microsoft Academic Search

Ultra wideband impulse radio is a promising radio technology for networks delivering extremely high data rates at short ranges. The use of extremely short duration pulses however makes synchronization task more difficult. In this paper a two-stage acquisition with serial search noncoherent correlator for time hopping impulse radio is proposed. The proposed two-stage acquisition scheme gets chip timing synchronization, and

Yuanliang Huang; Jiangzhou Wang

2007-01-01

260

UWB Tracking Algorithms: AOA and TDOA  

NASA Technical Reports Server (NTRS)

Ultra-Wideband (UWB) tracking prototype systems are currently under development at NASA Johnson Space Center for various applications on space exploration. For long range applications, a two-cluster Angle of Arrival (AOA) tracking method is employed for implementation of the tracking system; for close-in applications, a Time Difference of Arrival (TDOA) positioning methodology is exploited. Both AOA and TDOA are chosen to utilize the achievable fine time resolution of UWB signals. This talk presents a brief introduction to AOA and TDOA methodologies. The theoretical analysis of these two algorithms reveal the affecting parameters impact on the tracking resolution. For the AOA algorithm, simulations show that a tracking resolution less than 0.5% of the range can be achieved with the current achievable time resolution of UWB signals. For the TDOA algorithm used in close-in applications, simulations show that the (sub-inch) high tracking resolution is achieved with a chosen tracking baseline configuration. The analytical and simulated results provide insightful guidance for the UWB tracking system design.

Ni, Jianjun David; Arndt, D.; Ngo, P.; Gross, J.; Refford, Melinda

2006-01-01

261

79 GHz UWB automotive short range radar - Spectrum allocation and technology trends  

NASA Astrophysics Data System (ADS)

Automotive UWB (Ultra-Wideband) short range radar (SSR) is on the market as a key technology for novel comfort and safety systems. SiGe based 79 GHz UWB SRR will be a definite candidate for the long term substitution of the 24 GHz UWB SRR. This paper will give an overview of the finished BMBF joint project KOKON and the recently started successing project RoCC, which concentrate on the development of this technology and sensor demonstrators. In both projects, the responsibilities of Daimler AG deal with application based sensor specification, test and evaluation of realized sensor demonstrators. Recent UWB SRR frequency regulation approaches and activitites will be introduced. Furthermore, some first results of Daimler activities within RoCC will be presented, dealing with the packaging and operation of these sensors within the complex car environment.

Bloecher, H.-L.; Sailer, A.; Rollmann, G.; Dickmann, J.

2009-05-01

262

Photonic generation of UWB impulses by using a Fabry-Pérot semiconductor optical amplifier  

NASA Astrophysics Data System (ADS)

A novel approach to generating ultra-wideband (UWB) impulses based on a Mach-Zehnder modulator (MZM) and a Fabry-Pérot semiconductor optical amplifier (FP-SOA) is proposed and demonstrated. Both the carrier dynamic behavior of SOA and the feedback of FP cavity are exploited to generate a pair of polarity-reversed doublet-like impulses. Simulations and experiments are carried out to verify the UWB generation. In the experiment, the fractional bandwidths of the negative-doublet-like and the positive-doublet-like impulses are 100% and 108%, respectively. The bit error rate (BER) performance of the UWB before and after a span of 19-km standard single mode fiber (SSMF) transmission is also investigated and error-free performance can be achieved for each condition. Finally the UWB wireless transmission over a span of 10 cm is investigated.

Yu, Yuan; Dong, Jianji; Jiang, Fan; Luo, Bowen; Zhang, Xinliang

2014-03-01

263

Design and performance of an ultra-wideband stepped-frequency radar with precise frequency control for landmine and IED detection  

NASA Astrophysics Data System (ADS)

The Army Research Laboratory (ARL) has developed an impulse-based vehicle-mounted forward-looking ultra- wideband (UWB) radar for imaging buried landmines and improvised explosive devices (IEDs). However, there is no control of the radiated spectrum in this system. As part of ARL's Partnerships in Research Transition (PIRT) program, the above deficiency is addressed by the design of a Stepped-Frequency Radar (SFR) which allows for precise control over the radiated spectrum, while still maintaining an effective ultra-wide bandwidth. The SFR utilizes a frequency synthesizer which can be configured to excise prohibited and interfering frequency bands and also implement frequency-hopping capabilities. The SFR is designed to be a forward-looking ground- penetrating (FLGPR) Radar utilizing a uniform linear array of sixteen (16) Vivaldi notch receive antennas and two (2) Quad-ridge horn transmit antennas. While a preliminary SFR consisting of four (4) receive channels has been designed, this paper describes major improvements to the system, and an analysis of expected system performance. The 4-channel system will be used to validate the SFR design which will eventually be augmented in to the full 16-channel system. The SFR has an operating frequency band which ranges from 300 - 2000 MHz, and a minimum frequency step-size of 1 MHz. The radar system is capable of illuminating range swaths that have maximum extents of 30 to 150 meters (programmable). The transmitter has the ability to produce approximately -2 dBm/MHz average power over the entire operating frequency range. The SFR will be used to determine the practicality of detecting and classifying buried and concealed landmines and IEDs from safe stand-off distances.

Phelan, Brian R.; Sherbondy, Kelly D.; Ranney, Kenneth I.; Narayanan, Ram M.

2014-05-01

264

30 pJ/b, 67 Mbps, Centimeter-to-Meter Range Data Telemetry With an IR-UWB Wireless Link.  

PubMed

This paper reports an energy-efficient, impulse radio ultra wideband (IR-UWB) wireless link operating in 3-5 GHz for data telemetry over centimeter-to-meter range distances at rates extended to tens of Mbps. The link comprises an all-digital, integrated transmitter (TX) fabricated in 90 nm 1P/9M CMOS that incorporates a waveform-synthesis pulse generator and a timing generator for on-off-keying (OOK) pulse modulation and phase scrambling. The link also incorporates an energy-detection receiver (RX) realized with commercial off-the-shelf (COTS) components that performs radio-frequency (RF) filtering, amplification, logarithmic power detection for data demodulation and automatic level control for robust operation in the presence of distance variations. Employing a miniaturized, UWB, chip antenna for the TX and RX, wireless transmission of pseudo-random binary sequence (PRBS) data at rates up to 50 Mbps over 10 cm-1 m is shown. Further, employing a high-gain horn antenna for the RX, wireless transmission of PRBS data at rates up to 67 Mbps over 50 cm-4 m is shown with a TX energy consumption of 30 pJ/b (i.e., power consumption of 2 mW) from 1.2 V. The measured bit error rate (BER) in both cases is . Results from wireless recording of the background current of a carbon-fiber microelectrode (CFM) in one fast-scan cyclic voltammetry (FSCV) scan using the IR-UWB link are also included, exhibiting excellent match with those obtained from a conventional frequency-shift-keyed (FSK) link at  ? 433 MHz. PMID:25134088

Ebrazeh, Ali; Mohseni, Pedram

2014-08-12

265

Low-loss ultra-wideband transition between conductor-backed coplanar waveguide and substrate integrated waveguide  

Microsoft Academic Search

A novel transition between conductor-backed coplanar waveguide (CBCPW) and substrate integrated waveguide (SIW) is presented for microwave and millimeter-wave integrated circuit design. The proposed integrated transition that can provide simultaneous field and impedance matching, exhibits outstanding low-loss performances over an ultra-wideband range (entire Ka-band in our case). In this work, a generalized impedance inverter whose parameters are accurately extracted by

Xiao-Ping Chen; Ke Wu

2009-01-01

266

Ultra-Wideband Surface Acoustic Wave Devices Using Cu-Grating\\/Rotated-YX-LiNbO3Substrate Structure  

Microsoft Academic Search

This paper discusses the application of Love mode propagating on Cu-grating\\/rotated YX-LiNbO3-substrate structure to the development of ultra-wideband and low-loss RF surface acoustic wave (SAW) filters. Theoretical analysis suggested that high performance resonators with very small capacitance ratio would be realised using Cu gratings with a thickness of several percent of wavelength. It was also suggested that in particular, on

Ken-ya Hashimoto; Hiroki Asano; Tatsuya Omori; Masatsune Yamaguchi

2004-01-01

267

Ultra-Wideband and UniDirectional Radiation Slot Antenna for MultiBand Wireless Communication Applications  

Microsoft Academic Search

In this paper, a ultra-wideband slot antenna is proposed and developed for multi-band wireless communication applications.\\u000a The radiating slot is fed by a microstrip line with a microstrip fork shaped tuning stub and backed by a finite metallic reflector.\\u000a The frequency characteristic and radiation performance of the proposed antenna are successfully optimized and the related\\u000a prototypes are fabricated and tested.

Qinjiang Rao; Tayeb A. Denidni

2007-01-01

268

Fuzzy neighborhood filters for UWB range radios in multipath environments  

NASA Astrophysics Data System (ADS)

An ultra-wideband (UWB) inter-radio ranging technology with measurement resolution of +/-0.5 ft and range up to 0.5 kilometer under certain FCC regulation was recently introduced. However, measurement data are extremely erroneous due to stochastic variables in the device and multipath radio wave reflections. This paper presents fuzzy logic tuned double tracking filters as a solution to remove misinformation in the data. The 1st tracker locates the overall center of the data in the presence of the large sporadic noise. A fuzzy logic admits only neighborhood data to a 2nd tracker which takes care of smaller deviation noise. The fuzzy neighborhood filter approach has been successfully applied to clean up the UWB radio ranges. Experimental results are shown.

Cheok, Ka C.; Hudas, Gregory R.; Overholt, James L.

2008-04-01

269

A VLSI Neural Monitoring System With Ultra-Wideband Telemetry for Awake Behaving Subjects.  

PubMed

Long-term monitoring of neuronal activity in awake behaving subjects can provide fundamental information about brain dynamics for neuroscience and neuroengineering applications. Here, we present a miniature, lightweight, and low-power recording system for monitoring neural activity in awake behaving animals. The system integrates two custom designed very-large-scale integrated chips, a neural interface module fabricated in 0.5 ?m complementary metal-oxide semiconductor technology and an ultra-wideband transmitter module fabricated in a 0.5 ?m silicon-on-sapphire (SOS) technology. The system amplifies, filters, digitizes, and transmits 16 channels of neural data at a rate of 1 Mb/s. The entire system, which includes the VLSI circuits, a digital interface board, a battery, and a custom housing, is small and lightweight (24 g) and, thus, can be chronically mounted on small animals. The system consumes 4.8 mA and records continuously for up to 40 h powered by a 3.7-V, 200-mAh rechargeable lithium-ion battery. Experimental benchtop characterizations as well as in vivo multichannel neural recordings from awake behaving rats are presented here. PMID:23851199

Greenwald, E; Mollazadeh, M; Hu, C; Wei Tang; Culurciello, E; Thakor, V

2011-04-01

270

Accurate permittivity measurements for microwave imaging via ultra-wideband removal of spurious reflectors.  

PubMed

The use of microwave imaging is becoming more prevalent for detection of interior hidden defects in manufactured and packaged materials. In applications for detection of hidden moisture, microwave tomography can be used to image the material and then perform an inverse calculation to derive an estimate of the variability of the hidden material, such internal moisture, thereby alerting personnel to damaging levels of the hidden moisture before material degradation occurs. One impediment to this type of imaging occurs with nearby objects create strong reflections that create destructive and constructive interference, at the receiver, as the material is conveyed past the imaging antenna array. In an effort to remove the influence of the reflectors, such as metal bale ties, research was conducted to develop an algorithm for removal of the influence of the local proximity reflectors from the microwave images. This research effort produced a technique, based upon the use of ultra-wideband signals, for the removal of spurious reflections created by local proximity reflectors. This improvement enables accurate microwave measurements of moisture in such products as cotton bales, as well as other physical properties such as density or material composition. The proposed algorithm was shown to reduce errors by a 4:1 ratio and is an enabling technology for imaging applications in the presence of metal bale ties. PMID:22163668

Pelletier, Mathew G; Viera, Joseph A; Wanjura, John; Holt, Greg

2010-01-01

271

Accurate Permittivity Measurements for Microwave Imaging via Ultra-Wideband Removal of Spurious Reflectors  

PubMed Central

The use of microwave imaging is becoming more prevalent for detection of interior hidden defects in manufactured and packaged materials. In applications for detection of hidden moisture, microwave tomography can be used to image the material and then perform an inverse calculation to derive an estimate of the variability of the hidden material, such internal moisture, thereby alerting personnel to damaging levels of the hidden moisture before material degradation occurs. One impediment to this type of imaging occurs with nearby objects create strong reflections that create destructive and constructive interference, at the receiver, as the material is conveyed past the imaging antenna array. In an effort to remove the influence of the reflectors, such as metal bale ties, research was conducted to develop an algorithm for removal of the influence of the local proximity reflectors from the microwave images. This research effort produced a technique, based upon the use of ultra-wideband signals, for the removal of spurious reflections created by local proximity reflectors. This improvement enables accurate microwave measurements of moisture in such products as cotton bales, as well as other physical properties such as density or material composition. The proposed algorithm was shown to reduce errors by a 4:1 ratio and is an enabling technology for imaging applications in the presence of metal bale ties. PMID:22163668

Pelletier, Mathew G.; Viera, Joseph A.; Wanjura, John; Holt, Greg

2010-01-01

272

Improved resolution and reduced clutter in ultra-wideband microwave imaging using cross-correlated back projection: experimental and numerical results.  

PubMed

Microwave breast cancer detection is based on the dielectric contrast between healthy and malignant tissue. This radar-based imaging method involves illumination of the breast with an ultra-wideband pulse. Detection of tumors within the breast is achieved by some selected focusing technique. Image formation algorithms are tailored to enhance tumor responses and reduce early-time and late-time clutter associated with skin reflections and heterogeneity of breast tissue. In this contribution, we evaluate the performance of the so-called cross-correlated back projection imaging scheme by using a scanning system in phantom experiments. Supplementary numerical modeling based on commercial software is also presented. The phantom is synthetically scanned with a broadband elliptical antenna in a mono-static configuration. The respective signals are pre-processed by a data-adaptive RLS algorithm in order to remove artifacts caused by antenna reverberations and signal clutter. Successful detection of a 7?mm diameter cylindrical tumor immersed in a low permittivity medium was achieved in all cases. Selecting the widely used delay-and-sum (DAS) beamforming algorithm as a benchmark, we show that correlation based imaging methods improve the signal-to-clutter ratio by at least 10?dB and improves spatial resolution through a reduction of the imaged peak full-width half maximum (FWHM) of about 40-50%. PMID:21331362

Jacobsen, S; Birkelund, Y

2010-01-01

273

Improved Resolution and Reduced Clutter in Ultra-Wideband Microwave Imaging Using Cross-Correlated Back Projection: Experimental and Numerical Results  

PubMed Central

Microwave breast cancer detection is based on the dielectric contrast between healthy and malignant tissue. This radar-based imaging method involves illumination of the breast with an ultra-wideband pulse. Detection of tumors within the breast is achieved by some selected focusing technique. Image formation algorithms are tailored to enhance tumor responses and reduce early-time and late-time clutter associated with skin reflections and heterogeneity of breast tissue. In this contribution, we evaluate the performance of the so-called cross-correlated back projection imaging scheme by using a scanning system in phantom experiments. Supplementary numerical modeling based on commercial software is also presented. The phantom is synthetically scanned with a broadband elliptical antenna in a mono-static configuration. The respective signals are pre-processed by a data-adaptive RLS algorithm in order to remove artifacts caused by antenna reverberations and signal clutter. Successful detection of a 7?mm diameter cylindrical tumor immersed in a low permittivity medium was achieved in all cases. Selecting the widely used delay-and-sum (DAS) beamforming algorithm as a benchmark, we show that correlation based imaging methods improve the signal-to-clutter ratio by at least 10?dB and improves spatial resolution through a reduction of the imaged peak full-width half maximum (FWHM) of about 40–50%. PMID:21331362

Jacobsen, S.; Birkelund, Y.

2010-01-01

274

Adaptive and Ultra-Wideband Sampling via Signal Segmentation and Projection  

E-print Network

functionsfk are not band- limited. We discuss this in section 3.) For this choice of N, we compute f(t) = kZ f(t)[(k)Tc,(k@arl.army.mil Abstract: Adaptive frequency band (AFB) and ultra-wide-band (UWB) systems require either rapidly changing frequency band (AFB) and ultra-wide-band (UWB) systems, requiring either rapidly changing or very high

Boyer, Edmond

275

0.18 um 3.1-10.6 GHz CMOS UWB LNA with 25±1dB gain  

NASA Astrophysics Data System (ADS)

A 3.1-10.6 GHz ultra-wideband low noise-amplifier (UWB LNA) using standard 0.18 um CMOS technology which is applicable in telecommunication has been reported. A two-stage, common-gate in cascade with cascode, UWB LNA has been proposed to achieve more than 10 dB input and output return loss, maximum gain of 26 dB, and NF of 2.9 dB over the full frequency band. The proposed LNA consumes 10 mW from 1.8 V supply. The designed LNA has an excellent high gain in comparison with previous works.

Shamsadini, Shila; Kashani, Farokh Hojat; Bathaei, Neda

2011-05-01

276

Effects of Quantization in Systolic 2D IIR Beam Filters on UWB Wireless Communications  

Microsoft Academic Search

Ultra-wideband (UWB) wireless beamforming systems may potentially be implemented digitally at multi-gigahertz clock frequencies\\u000a using low-precision systolic array realizations of two-dimensional (2D) infinite impulse response (IIR) beam plane-wave filters.\\u000a The finite precision performance of such filters is analyzed in terms of quantization noise. Extensive Monte Carlo simulations\\u000a are performed using test vectors that are derived from 2D finite-difference time-domain (FDTD)

Sean Victor Hum; Leonard T. Bruton

277

Ultra-wideband coaxial hybrid coupler for load resilient ion cyclotron range of frequency heating at fusion plasmas  

SciTech Connect

We designed a high power and ultra-wideband two-section 3 dB coaxial hybrid coupler for load resilient ion cyclotron range of frequency heating by configuring asymmetric impedance matching using a three-dimensional simulation code, hfss. By adjusting the characteristic impedances of main and coupled lines of the hybrid coupler, we realized that the bandwidth of the proposed circuit is not only wider than that of a conventional three-section coupler, but also that the bandwidth is almost twice as wide compared to the conventional two-section hybrid coupler while maintaining the identical overall size.

Kim, H. J.; Bae, Y. S.; Yang, H. L.; Kwak, J.-G. [National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of); Wang, S. J. [Korea Atomic Energy Research Institute, Daejeon 305-333 (Korea, Republic of); Kim, B. K.; Choi, J. J. [Department of Electronics Convergence Engineering, Kwangwoon University, Seoul 139-701 (Korea, Republic of)

2012-06-25

278

UWB Two-Cluster AOA Tracking Prototype System Design  

NASA Technical Reports Server (NTRS)

This presentation discusses a design effort for a prototype ultra-wideband (UWB) tracking system that is currently under development at NASA Johnson Space Center (JSC). The system is being studied for use in tracking of lunar/Mars rovers during early exploration missions when satellite navigation systems are not available. The UWB technology is exploited to implement the tracking system due to its properties such as fine time resolution, low power spectral density and multipath immunity. A two cluster prototype design using commercially available UWB radios is employed to implement the Angle of Arrival (AOA) tracking methodology in this design effort. In order to increase the tracking range, low noise amplifiers (LNA) and high gain horns are used at the receiving sides. Field tests were conducted jointly with the Science and Crew Operation Utility Testbed (SCOUT) vehicle near the Meteor Crater in Arizona to test the tracking capability for a moving target in an operational environment. These tests demonstrate that the UWB tracking system can co-exist with other on-board radio frequency (RF) communication systems (such as Global Positioning System (GPS), video, voice and telemetry systems), and that a tracking resolution less than 1% of the range can be achieved.

Ngo, Phong H.; Arndt, D.; Phan, C.; Gross, J.; Jianjun; Rafford, Melinda

2006-01-01

279

UWB Tracking System Design for Lunar/Mars Exploration  

NASA Technical Reports Server (NTRS)

This paper describes a design effort for a prototype ultra-wideband (UWB) tracking system that is currently under development at NASA Johnson Space Center (JSC). The system is being studied for use in tracking of lunar/Mars rovers during early exploration missions when satellite navigation systems are not available. The UWB technology is exploited to implement the tracking system due to its properties such as high data rate, fine time resolution, low power spectral density, and multipath immunity. A two-cluster prototype design using commercially available UWB products is proposed to implement the Angle Of Arrival (AOA) tracking methodology in this research effort. An AOA technique using the Time Difference Of Arrival (TDOA) information is utilized for location estimation in the prototype system, not only to exploit the precise time resolution possible with UWB signals, but also to eliminate the need for synchronization between the transmitter and the receiver. After the UWB radio at each cluster is used to obtain the TDOA estimates from the UWB signal sent from the target, the TDOA data is converted to AOA data to find the angle of arrival, assuming this is a far field application. Since the distance between two clusters is known, the target position is computed by a simple triangulation. Simulations show that the average tracking error at a range of 610 meters is 2.7595 meters, less than 0.5% of the tracking range. Outdoor tests to track the SCOUT vehicle (The Science Crew Operations and Utility Testbed) near the Meteor Crater, Flagstaff, Arizona were performed on September 12-13, 2005. The tracking performance was obtained with less than 1% tracking error at ranges up to 2000 feet. No RF interference with on-board GPS, video, voice and telemetry systems was detected. Outdoor tests demonstrated the UWB tracking capability.

Ni, Jianjun; Arndt, Dickey; Ngo, Phong; Phan, Chau; Gross, Julia

2006-01-01

280

A 264 MHz CMOS Gm—C LPF for ultra-wideband standard  

NASA Astrophysics Data System (ADS)

A 264 MHz CMOS 4th Gm—C LPF target for the UWB standard is presented. The filter is designed by cascading two biquad cells. Compared with the previously published biquad cells, the biquad proposed here saves 1 transconductor, 3 CMFB networks and 2 capacitors. Benefiting from these merits, the power consumption and chip area of the 4th order UWB LPF are reduced dramatically without other characteristics being affected. The LPF is designed and fabricated with TSMC 0.18 ?m 1P6M CMOS technology. The implemented LPF achieves a power gain of -0.5 dB. The measured frequency response matches well with that of the simulating results. The core chip area is only 0.06 mm2, which has a wonderful advantage over those from similar work. The LPF excluding test-buffers dissipates a total current of 3 mA from the 1.8 V power supply.

Zhendong, Gao; Zhiqiang, Li; Hongkun, Li; Haiying, Zhang

2010-11-01

281

Design of all-optical UWB monocycle generation for UWB-over-fibre communications  

NASA Astrophysics Data System (ADS)

We propose and demonstrate a novel approach generating ultrawideband (UWB) monocycle pulses using cross phase modulation (XPM) of the semiconductor optical amplifier (SOA). A pair of polarity-reversed UWB monocycle pulses is achieved by locating the probe carrier at the positive and negative linear slopes of the filter. We achieve different UWB spectrum width by 25ps- and 50ps-width Gauss pulse injection. The generated monocycle pulses can be controlled by either optical Gauss pulse or both injections, which function as logic OR-monocycle. It has potential applications in UWB-over-fiber communications.

Dong, Jianji; Zhang, Xinliang; Xu, Jing; Huang, Dexiu

2007-11-01

282

Performance of inter-chip RF-interconnect using CPW, capacitive coupler, and UWB transceiver  

Microsoft Academic Search

A novel inter-chip RF-interconnect system operating in the range of 22-29 GHz is described and analyzed in terms of system bit error rate (BER) performance. After characterizing the interconnect channel, plotting the transmitted and received ultra-wideband pulses, and estimating the switching noise power density by proposing a novel switching noise attack model, we finally get the results of the system

M. Sun; Y. P. Zhang

2005-01-01

283

Joint semi-blind channel and timing estimation for generalized UWB transmitted reference systems  

Microsoft Academic Search

Synchronization is one of the most critical issues in ultra-wideband communications due to the short duration of the pulses. In this work, a semi-blind synchronization scheme based on maximum-likelihood techniques to recover both symbol and frame timing is developed. The proposed algorithm performs joint timing and channel estimation and is thus robust against moderate timing errors. The probability of acquisition

Stefan Franz; Cecilia Carbonelli; Urbashi Mitra

2007-01-01

284

Multiple Access Interference Reduction Using Received Response Code Sequence for DS-CDMA UWB System  

NASA Astrophysics Data System (ADS)

This paper proposes a combination of novel Received Response (RR) sequence at the transmitter and a Matched Filter-RAKE (MF-RAKE) combining scheme receiver system for the Direct Sequence-Code Division Multiple Access Ultra Wideband (DS-CDMA UWB) multipath channel model. This paper also demonstrates the effectiveness of the RR sequence in Multiple Access Interference (MAI) reduction for the DS-CDMA UWB system. It suggests that by using conventional binary code sequence such as the M sequence or the Gold sequence, there is a possibility of generating extra MAI in the UWB system. Therefore, it is quite difficult to collect the energy efficiently although the RAKE reception method is applied at the receiver. The main purpose of the proposed system is to overcome the performance degradation for UWB transmission due to the occurrence of MAI during multiple accessing in the DS-CDMA UWB system. The proposed system improves the system performance by improving the RAKE reception performance using the RR sequence which can reduce the MAI effect significantly. Simulation results verify that significant improvement can be obtained by the proposed system in the UWB multipath channel models.

Toh, Keat Beng; Tachikawa, Shin'ichi

285

Novel Dual-band Slot Antenna Design for Bluetooth and UWB Applications  

NASA Astrophysics Data System (ADS)

A novel technique to introduce an additional low frequency band to compact ultra wideband (UWB) slot antennas is proposed in this paper. To get an additional Bluetooth band, a parasitic strip is mounted on the back side of the slot edge. Because of the interaction of the strip and the slot edge, the Bluetooth band can be obtained while a notch band between the Bluetooth band and UWB band also appears. Two types of feeding, coplanar waveguide and microstrip line, are investigated. The proposed antennas are both fabricated on a low-cost FR4 substrate and have compact size (24 mm × 28 mm × 1 mm). The good agreement between measured and simulated results verifies our design.

Huang, Hai-Yan; Shao, Wei; Wang, Bing-Zhong; Ma, Xiao-Liang

2014-05-01

286

Remotely-sensed TOA interpretation of synthetic UWB based on neural networks  

NASA Astrophysics Data System (ADS)

Because of the good penetration into many common materials and inherent fine resolution, Ultra-Wideband (UWB) signals are widely used in remote sensing applications. Typically, accurate Time of Arrival (TOA) estimation of the UWB signals is very important. In order to improve the precision of the TOA estimation, a new threshold selection algorithm using Artificial Neural Networks (ANN) is proposed which is based on a joint metric of the skewness and maximum slope after Energy Detection (ED). The best threshold based on the signal-to-noise ratio (SNR) is investigated and the effects of the integration period and channel model are examined. Simulation results are presented which show that for the IEEE802.15.4a channel models CM1 and CM2, the proposed ANN algorithm provides better precision and robustness in both high and low SNR environments than other ED-based algorithms.

Zhang, Hao; Cui, Xue-rong; Gulliver, T. Aaron

2012-12-01

287

An ultra-wideband wire spiral antenna for in-body communications using different material matching layers.  

PubMed

In this work an ultra-wideband wire antenna was designed and fabricated for transmitting/receiving signals to/from inside the human body. The antenna provides high gain and thus high field intensity in its broadside direction; hence, a high energy density wireless can be established with the inner body. The proposed antenna operates in the frequency band of 3-10 GHz with an impedance of 200 Ohms in free space. The antenna was embedded in different materials with permittivity values ranging from 12 to 74 in order to evaluate the matching layer effect on wave propagation from outside to inside the body. The antenna port impedance was adjusted by using matching circuits. The electric field intensity inside the human chest was calculated for different materials and depths. The best improvement in wave penetration was obtained for the frequency band of 750-1000 MHz by embedding the antenna inside a material with permittivity equal to 27. PMID:25571603

Khaleghi, Ali; Balasingham, Ilangko; Chavez-Santiago, Raul

2014-08-01

288

UWB communication receiver feedback loop  

DOEpatents

A novel technique and structure that maximizes the extraction of information from reference pulses for UWB-TR receivers is introduced. The scheme efficiently processes an incoming signal to suppress different types of UWB as well as non-UWB interference prior to signal detection. Such a method and system adds a feedback loop mechanism to enhance the signal-to-noise ratio of reference pulses in a conventional TR receiver. Moreover, sampling the second order statistical function such as, for example, the autocorrelation function (ACF) of the received signal and matching it to the ACF samples of the original pulses for each transmitted bit provides a more robust UWB communications method and system in the presence of channel distortions.

Spiridon, Alex (Palo Alto, CA); Benzel, Dave (Livermore, CA); Dowla, Farid U. (Castro Valley, CA); Nekoogar, Faranak (San Ramon, CA); Rosenbury, Erwin T. (Castro Valley, CA)

2007-12-04

289

Provision of IR-UWB wireless and baseband wired services over a WDM-PON.  

PubMed

A simple scheme to simultaneously generate an on-off keying or bi-phase modulation (BPM) impulse radio ultra wideband (IR-UWB) signal and a baseband wired signal in the optical domain using a dual-drive modulator is proposed and demonstrated. Although the two signals have spectral overlap in the optical spectrum, they are located at different frequency bands when converted to electrical signals at a photodetector (PD), which can be well separated by an electrical filter. An experiment is carried out. Eye diagrams, electrical spectra and BER measurements show that the co-channel interference between the UWB and the wired signals is small for a single-channel 36-km fiber link to provide 1.25-Gb/s UWB wireless and 1.25-Gb/s baseband wired services. The inter-channel interference is also small and negligible when the link is operated together with two other 1.25 Gb/s baseband wired links, which demonstrates that a conventional WDM-PON can be upgraded to provide additional UWB services without affecting the existing services by modifying the modulators in the center office and inserting UWB antennas in the optical network units. PMID:22274021

Pan, Shilong; Yao, Jianping

2011-12-12

290

A Framework for UWB-Based Communication and Location Tracking Systems for Wireless Sensor Networks  

PubMed Central

Ultra wideband (UWB) radio technology is nowadays one of the most promising technologies for medium-short range communications. It has a wide range of applications including Wireless Sensor Networks (WSN) with simultaneous data transmission and location tracking. The combination of location and data transmission is important in order to increase flexibility and reduce the cost and complexity of the system deployment. In this scenario, accuracy is not the only evaluation criteria, but also the amount of resources associated to the location service, as it has an impact not only on the location capacity of the system but also on the sensor data transmission capacity. Although several studies can be found in the literature addressing UWB-based localization, these studies mainly focus on distance estimation and position calculation algorithms. Practical aspects such as the design of the functional architecture, the procedure for the transmission of the associated information between the different elements of the system, and the need of tracking multiple terminals simultaneously in various application scenarios, are generally omitted. This paper provides a complete system level evaluation of a UWB-based communication and location system for Wireless Sensor Networks, including aspects such as UWB-based ranging, tracking algorithms, latency, target mobility and MAC layer design. With this purpose, a custom simulator has been developed, and results with real UWB equipment are presented too. PMID:22164120

Chóliz, Juan; Hernández, Ángela; Valdovinos, Antonio

2011-01-01

291

A 60 GHz MMIC pHEMT image reject mixer with integrated ultra wideband IF hybrid and 30 dB of image rejection ratio  

Microsoft Academic Search

A 60 GHz image reject mixer (IRM) with an integrated ultra wideband IF hybrid has been designed, fabricated and characterized in a commercial pHEMT MMIC process. A measured conversion loss (Lc) of 10.2 to 11.4 dB over the frequency range 55 to 65 GHz is obtained with a state-of-the-art image rejection ratio (IRR) of 30 dB at the 60 GHz

Sten E. Gunnarsson; Dan Kuylenstierna; Herbert Zirath

2005-01-01

292

Mary pulse shape modulation for PSWF-based UWB systems in multipath fading environment  

Microsoft Academic Search

M-ary pulse shape modulation (PSM) has been proposed for achieving a high data rate even in severe multipath fading environments, based on the orthogonality of pulse waveforms of prolate spheroidal wave functions (PSWF). With respect to the PSWF-based M-ary PSM proposal, adaptive guard-time and selective-Rake receivers with different combining fingers are also considered The BER performance of the M-ary PSM,

Kazuto USUDA; Honggang Zhang; Masao NAKAGAWA

2004-01-01

293

A 12mW 264MHz high linearity sharp roll-off CMOS opamp-RC low-pass filter for MB-OFDM UWB systems  

Microsoft Academic Search

This paper presents a high linearity wideband sharp roll-off Opamp-RC low-pass filter (LPF) for Ultra wideband (UWB) applications.\\u000a The proposed LPF is composed of three biquads’ transfer functions with different Q-factors in series. Sharp roll-off is attributed\\u000a to the steep slope of the peaking of a biquad transfer function with a high Q-factor. The superposition of these biquads also\\u000a helps

Anh Tuan Phan; Ronan Farrell; Sang-Gug Lee

2009-01-01

294

A Hybrid TOA-Fingerprinting Based Localization of Mobile Nodes Using UWB Signaling for Non Line-Of-Sight Conditions  

PubMed Central

Recently, Impulse Radio Ultra Wideband (IR-UWB) signaling has become popular for providing precise location accuracy for mobile and wireless sensor node localization in the indoor environment due to its large bandwidth and high time resolution while providing ultra-high transmission capacity. However, the Non-line-of-sight (NLOS) error mitigation has considerable importance in localization of wireless nodes. In order to mitigate NLOS errors in indoor localization this paper proposes and investigates a novel approach which creates a hybrid combination of channel impulse response (CIR)-based fingerprinting (FP) positioning and an iterative Time of Arrival (TOA) real time positioning method using Ultra Wideband (UWB) signaling. Besides, to reduce the calculation complexities in FP method, this paper also introduces a unique idea for the arrangement of reference nodes (or tags) to create a fingerprinting database. The simulation results confirm that the proposed hybrid method yields better positioning accuracies and is much more robust in NLOS error mitigation than TOA only and FP only and a conventional iterative positioning method. PMID:23112651

Kabir, Md. Humayun; Kohno, Ryuji

2012-01-01

295

Photonic envelope detection and fiber transmission of 24 GHz IR-UWB signal based on phase modulation  

NASA Astrophysics Data System (ADS)

A novel scheme for photonic envelope detection and fiber transmission of 24 GHz impulse radio ultra-wideband (IRUWB) signal is proposed based on phase modulator (PM). In the system, an optics assisted envelope detection unit (OAEDU) is used for filtering one of the first sidebands at the output of PM, then this narrow band optical signal transfers over single-mode fiber (SMF), and the envelope of 24 GHz IR-UWB signal is obtained after photodetection (PD) and low pass filter (LPF). The numerical simulation results show that the combination of PM and OAEDU can alleviate the fiber chromatic dispersion (CD) effectively. The proposed system may provide a simple and cost-effective solution for IR-UWB receiver.

Yin, Xiao-li; Han, Jing-jing; Xu, Can; Hao, Ji; Xin, Xiang-jun; Li, Li

2015-01-01

296

Development of an electronically tunable ultra-wideband radar imaging sensor and its components  

E-print Network

and receiver respectively for timing control. A novel integrated CSH (Coupled-Slotline Hybrid)sampling mixer has been developed along with the design of the strobe pulse generator appropriate for the impulse radar system. The integrated sampling mixer has...

Han, Jeongwoo

2006-08-16

297

On IEEE 802.15.6 IR-UWB receivers - simulations for DBPSK modulation.  

PubMed

In 2002, Federal Communications Commission (FCC) was the first in defining regulations for ultra wideband (UWB) communications followed by Europe and Japan some years later. Focusing on impulse radio (IR) UWB, in 2007 was the time for the first published standard targeting in personal area networks, released by the IEEE. The second IEEE released standard including UWB definitions is targeted for wireless body area networks (WBAN) and was published in 2012. As the wireless communications has been and will be passing through almost any levels in society, the natural step with WBAN is using it in different medical, healthcare and wellbeing applications. The arguments for these are related to the modern lifestyle, in which people have increasingly more free time and are more interested in taking care of their health and wellbeing. Another challenge is the population composition, i.e., aging in developed countries which call for new solutions and procedures, particularly from cost wise. In this paper, we are evaluating UWB receivers based on the IEEE 802.15.6 physical layer definitions and capable of detecting differentially encoded modulation. The evaluation is performed using two different WBAN channel models. PMID:24110027

Niemelä, Ville; Hämäläinen, Matti; Iinatti, Jari

2013-01-01

298

Design and simulation of gain-flattened ultra wideband fiber amplifiers covering S-, C-, and L-bands  

NASA Astrophysics Data System (ADS)

A novel design of a gain-flattened amplifier that covers an ultra-wideband including the S-, C-, and L-bands is presented. The amplifier is comprised of a split-band structure, which amplifies the S-, C-, and L-band signals in separate paths then recombines the amplified signals for the final output to the transmission fiber. For C-band amplification, a two-stage erbium doped fiber amplifier (EDFA) with mid-stage gain equalization filter (GEF) topology was used, for L-band amplification, single-stage longer EDFA topology was used. While for S-band amplification, a Raman fiber amplifier (RFA) with counter-propagating multiple-pump configuration was adopted. Using the VPIcomponentMaker(TM) software package from VPI Systems(TM), the design was simulated and tested for optimization. Computer simulations analyzed the gain and noise-figure of the novel amplifier. Approximately 30-dB gain with an overall gain ripple less than 1.6 dB and low noise-figure, and gain-bandwidth over 120 nm can be achieved. It encompasses more than 144 ITU-T channels at 100 GHz spacing. Comparing with previous reported work in the literature, the amplification range of the novel fiber amplifier not only covers the C- and L-bands, but also covers the S-band, which is the first investigation of this type. And hasn't been reported in literature by others for discrete amplification. This makes the novel amplifier described here as having the widest gain-flattened amplification bandwidth range among the discrete fiber amplifiers investigated till today.

Cao, Yang

299

An ultra-wideband tunable multi-wavelength Brillouin fibre laser based on a semiconductor optical amplifier and dispersion compensating fibre in a linear cavity configuration  

NASA Astrophysics Data System (ADS)

A multi-wavelength Brillouin fibre laser (MBFL) with an ultra-wideband tuning range from 1420 nm to 1620 nm is demonstrated. The MBFL uses an ultra-wideband semiconductor optical amplifier (SOA) and a dispersion compensating fibre (DCF) as the linear gain medium and nonlinear gain medium, respectively. The proposed MBFL has a wide tuning range covering the short (S-), conventional (C-) and long (L-) bands with a wavelength spacing of 0.08 nm, making it highly suitable for DWDM system applications. The output power of the observed Brillouin Stokes ranges approximately from —5.94 dBm to —0.41 dBm for the S-band, from —4.34 dBm to 0.02 dBm for the C-band and from —2.19 dBm to 0.39 dBm for the L-band. The spacing between each adjacent wavelengths of all the three bands is about 0.08 nm, which is approximately 10.7 GHz for the frequency domain.

Zulkifli, M. Z.; Ahmad, H.; Hassan, N. A.; Jemangin, M. H.; Harun, S. W.

2011-07-01

300

Ultra wide band signal design by angular and radial prolate spheroidal wave functions (PSWF)  

Microsoft Academic Search

Prolate spheroidal wave functions (PSWF) provide significant advantage in ultra wideband (UWB) pulse-shapes design because of the time limited nature and wide bandwidth of such orthogonal signal waveforms. In this paper, we show the design procedure for UWB pulses utilizing the joining properties of radial and angular PSWF. Results in the paper demonstrate utility of eigenvalues and power spectral properties

D. Adhikari; C. Bhattacharya

2011-01-01

301

Development of a Multiple-Input Multiple-Output Ultra-Wideband System Emulator G Tsao, K Sasloglou, L Petropoulakis, R Atkinson, I Andonovic, I A Glover  

E-print Network

narrowband transmission loss models from the resulting UWB database. The extraction of a UWB channel model position modulation (PPM) of impulses in impulse radio (IR), conventional spread spectrum methods, OFDM the UWB database and section 5 draws some conclusions. II. MEASUREMENT METHODOLOGY The frequency domain

Atkinson, Robert C

302

Swarm optimized UWB-PPM and protocol design for sensor network  

NASA Astrophysics Data System (ADS)

In this paper, a swarm based ultra-wideband waveform and routing protocol is used for communicating messages in the form of short pulses in sensor based health care application. Due to the time sensitivity of the application, a cognitive protocol is applied to make decisions based on resource availability and quality-of-service. The combination of swarm based physical and routing layer protocol helps in achieving an energy, bandwidth and time efficient application. This paper compares the performance of cross layer protocol when exhaustive search and swarm based waveform design is used.

Muraleedharan, Rajani; Osadciw, Lisa Ann; Gao, Weihua

2009-05-01

303

A novel through-wall respiration detection algorithm using UWB radar.  

PubMed

Through-wall respiration detection using Ultra-wideband (UWB) impulse radar can be applied to the post-disaster rescue, e.g., searching living persons trapped in ruined buildings after an earthquake. Since strong interference signals always exist in the real-life scenarios, such as static clutter, noise, etc., while the respiratory signal is very weak, the signal to noise and clutter ratio (SNCR) is quite low. Therefore, through-wall respiration detection using UWB impulse radar under low SNCR is a challenging work in the research field of searching survivors after disaster. In this paper, an improved UWB respiratory signal model is built up based on an even power of cosine function for the first time. This model is used to reveal the harmonic structure of respiratory signal, based on which a novel high-performance respiration detection algorithm is proposed. This novel algorithm is assessed by experimental verification and simulation and shows about a 1.5dB improvement of SNR and SNCR. PMID:24109862

Li, Xin; Qiao, Dengyu; Li, Ye; Dai, Huhe

2013-01-01

304

SEMICONDUCTOR INTEGRATED CIRCUITS: A 3-5 GHz CMOS UWB power amplifier with ±8 ps group delay ripple  

NASA Astrophysics Data System (ADS)

A differential power amplifier (PA), designed using the linear-phase filter model, for a BPSK modulated ultra-wideband (UWB) system operating in the 3-5 GHz frequency range is presented. The proposed PA was fabricated using 0.18 ?m SMIC CMOS technology. To achieve sufficient linearity and efficiency, this PA operates in the class-AB region, delivering an output power of 8.5 dBm at an input-1 dB compression point of -0.5 dBm. It consumes 28.8 mW, realizing a flat gain of 9.11 ± 0.39 dB and a very low group delay ripple of ±8 ps across the whole band of operation.

Tianzuo, Xi; Lu, Huang; Zhong, Zheng; Lisong, Feng

2010-04-01

305

A progressive processing method for breast cancer detection via UWB based on an MRI-derived model  

NASA Astrophysics Data System (ADS)

Ultra-wideband (UWB) microwave imaging is a promising method for breast cancer detection based on the large contrast of electric parameters between the malignant tumor and its surrounded normal breast organisms. In the case of multiple tumors being present, the conventional imaging approaches may be ineffective to detect all the tumors clearly. In this paper, a progressive processing method is proposed for detecting more than one tumor. The method is divided into three stages: primary detection, refocusing and image optimization. To test the feasibility of the approach, a numerical breast model is developed based on the realistic magnetic resonance image (MRI). Two tumors are assumed embedded in different positions. Successful detection of a 3.6 mm-diameter tumor at a depth of 42 mm is achieved. The correct information of both tumors is shown in the reconstructed image, suggesting that the progressive processing method is promising for multi-tumor detection.

Xiao, Xia; Song, Hang; Wang, Zong-Jie; Wang, Liang

2014-07-01

306

UWB-WBAN sensor node design.  

PubMed

In this paper, we discuss the hardware development of a UWB sensor node for wireless body area networks. A few unique UWB pulse generation techniques have been discussed. The sensor node transmits multiple pulses per bit to increase the average power of the transmitted signal in order to improve the bit-error rate (BER) performance. The multiple-pulse per bit technique is also used as the coding scheme to identify the individual sensor nodes when more than one sensor forms a network. The sensors nodes are able to transmit body signals up to 2 m with a BER lower than 10(-5). PMID:22254770

Keong, Ho Chee; Yuce, M R

2011-01-01

307

Reconfigurable UWB Bandpass Filter with Flexible Notch Characteristics  

NASA Astrophysics Data System (ADS)

The thesis reports a compact tunable ultra-wideband (UWB) notch filter using hybrid microstrip and coplanar waveguide (CPW) structure. The tunable notch is implemented to filter out the wireless local area network (WLAN) channels from 5GHz to 6GHz. The proposed structure utilizes the resonance of open ended stubs to achieve transmission zeroes in the filter passband. Varactors and by-pass capacitors are then introduced for dynamic tunability of notch. Further, the electromagnetic decoupling of the two resonators leads to tunable bandwidth of notch. DC bias circuitry is implemented to control the varactor capacitances. Rejection levels up to 25 dB are attained using this technique while maintaining insertion loss levels below 2.5 dB in the passband. The reconfigurability of bandwidth is shown by maintaining a constant bandwidth of 150 MHz across the WLAN band for the notch. The filter achieves an excellent wide bandwidth (from 2.5 GHz to 8.5 GHz) using multimode-resonator (MMR) based topology which makes the filter one wavelength long at the central frequency.

Dhwaj, Kirti

308

Exact Error Rate Analysis for Pulsed DS- and Hybrid DS/TH-CDMA in Nakagami Fading  

NASA Astrophysics Data System (ADS)

Exact bit error probabilities (BEP) are derived in closed-form for binary pulsed direct sequence (DS-) and hybrid direct sequence time hopping code division multiple access (DS/TH-CDMA) systems that have potential applications in ultra-wideband (UWB) communications. Flat Nakagami fading channel is considered and the characteristic function (CF) method is adopted. An exact expression of the CF is obtained through a straightforward method, which is simple and good for any arbitrary pulse shape. The CF is then used to obtain the exact BEP that requires less computational complexity than the method based on improved Gaussian approximation (IGA). It is shown under identical operating conditions that the shape of the CF, as well as, the BEP differs considerably for the two systems. While both the systems perform comparably in heavily faded channel, the hybrid system shows better BEP performance in lightly-faded channel. The CF and BEP also strongly depend on chip length and chip-duty that constitute the processing gain (PG). Different combinations of the parameters may result into the same PG and the BEP of a particular system for a constant PG, though remains nearly constant in a highly faded channel, may vary substantially in lightly-faded channel. A comparison of the results from the exact method with those from the standard Gaussian approximation (SGA) reveals that the SGA, though accurate for both the systems in highly-faded channel, becomes extremely optimistic for low-duty systems in lightly-faded channel. The SGA also fails to track several other system trade-offs.

Rahman, Mohammad Azizur; Sasaki, Shigenobu; Kikuchi, Hisakazu; Harada, Hiroshi; Kato, Shuzo

309

Hybrid UWB and WiMAX radio-over-multi-mode fibre for in-building optical networks  

NASA Astrophysics Data System (ADS)

In this paper the use of hybrid WiMedia-defined ultra-wideband (UWB) and IEEE 802.16d WiMAX radio-over-fibre is proposed and experimentally demonstrated for multi-mode based in-building optical networks with the advantage of great immunity to optical transmission impairments. In the proposed approach, spectral coexistence of both signals must be achieved with negligible mutual interference. The experimental study performed addressed an indoor configuration with 50 ?m multi-mode fibres (MMF) and 850 nm vertical-cavity surface-emitting laser (VCSEL) transmitters. The results indicate that the impact of the wireless convergence in radio-over-multi-mode fibre (RoMMF) is significant for UWB transmissions, mainly due to MMF dispersion and electrooptical (EO) devices with limited bandwidth. On the other hand, WiMAX transmission is feasible for a 300 m MMF and 30 m wireless link in the presence of UWB, with -31 dBm WiMAX EVM.

Perez, J.; Llorente, R.

2014-01-01

310

Performance Evaluation of a 60-GHz Multi-band OFDM (MB-OFDM) Ultra-Wideband Radio-Over-Fibre System  

E-print Network

GHz band. The impact of the non-linearity of the MZM, fibre transmission and the received optical to increase the transmission distance of UWB, a low-cost solution is to employ transmission over fibre. This enables us to combine the above-mentioned advantages of UWB with the advantages optical fibre offers

Haddadi, Hamed

311

Studies on an Iterative Frequency Domain Channel Estimation Technique for MIMO-UWB Communications  

NASA Astrophysics Data System (ADS)

MIMO (Multiple-Input Multiple-Output) technologies have attracted much interest for high-rate and high-capacity wireless communications. MIMO technologies under frequency-selective fading environments (wideband MIMO technologies) have also been studied. A wideband MIMO system is affected by ISI (Inter Symbol Interference) and CCI (Co-Channel Interference). Hence, we need a MIMO signal detection technique that simultaneously suppresses ISI and CCI. The OFDM system and SC-FDE (Single Carrier-Frequency Domain Equalization) techniques are often used for suppressing ISI. By employing these techniques with the ZF (Zero Forcing) or the MMSE (Minimum Mean Square Error) spatial filtering technique, we can cancel both ISI and CCI. To use ZF or MMSE, we need channel state information for calculating the receive weights. Although an LS (Least Square) channel estimation technique has been proposed for MIMO-OFDM systems, it needs a large estimation matrix at the receiver side to obtain sufficient estimation performance in heavy multipath environments. However, the use of a large matrix increases computational complexity and the circuit size. We use frequency domain channel estimation to solve these problems and propose an iterative method for achieving better estimation performance. In this paper, we assume the use of a MIMO-UWB system that employs a UWB-IR (Ultra-Wideband Impulse Radio) scheme with the FDE technique as the wideband wireless transmission scheme for heavy multipath environments, and we evaluate the iterative frequency domain channel estimation through computer simulations and computational complexity calculations.

Takanashi, Masaki; Ogawa, Yasutaka; Nishimura, Toshihiko; Ohgane, Takeo

312

Design of UWB Monopole Antenna with Dual Notched Bands Using One Modified Electromagnetic-Bandgap Structure  

PubMed Central

A modified electromagnetic-bandgap (M-EBG) structure and its application to planar monopole ultra-wideband (UWB) antenna are presented. The proposed M-EBG which comprises two strip patch and an edge-located via can perform dual notched bands. By properly designing and placing strip patch near the feedline, the proposed M-EBG not only possesses a simple structure and compact size but also exhibits good band rejection. Moreover, it is easy to tune the dual notched bands by altering the dimensions of the M-EBG. A demonstration antenna with dual band-notched characteristics is designed and fabricated to validate the proposed method. The results show that the proposed antenna can satisfy the requirements of VSWR < 2 over UWB 3.1–10.6?GHz, except for the rejected bands of the world interoperability for microwave access (WiMAX) and the wireless local area network (WLAN) at 3.5?GHz and 5.5?GHz, respectively. PMID:24170984

Xu, Ziqiang

2013-01-01

313

Low-power wide-locking-range injection-locked frequency divider for OFDM UWB systems  

NASA Astrophysics Data System (ADS)

This paper describes a divide-by-two injection-locked frequency divider (ILFD) for frequency synthesizers as used in multiband orthogonal frequency division multiplexing (OFDM) ultra-wideband (UWB) systems. By means of dual-injection technique and other conventional tuning techniques, such as DCCA and varactor tuning, the divider demonstrates a wide locking range while consuming much less power. The chip was fabricated in the Jazz 0.18 ?m RF CMOS process. The measurement results show that the divider achieves a locking range of 4.85 GHz (6.23 to 11.08 GHz) at an input power of 8 dBm. The core circuit without the test buffer consumes only 3.7 mA from a 1.8 V power supply and has a die area of 0.38 × 0.28 mm2. The wide locking range combined with low power consumption makes the ILFD suitable for its application in UWB systems.

Jiangwei, Yin; Ning, Li; Renliang, Zheng; Wei, Li; Junyan, Ren

2009-05-01

314

A Study on Performance Enhancement of Packet Detection in MB-OFDM UWB Systems  

NASA Astrophysics Data System (ADS)

This paper presents a high performance and hardware efficient packet detection structure, which employs a cross correlator for the M-sample time delayed correlation operation and a signal power calculator using the received input samples less than or equal to a zero-padded suffix of length M. We investigate the detailed characteristics of the proposed packet detector. In this paper, the performance of a class of packet detection algorithms in the ultra-wideband (UWB) channel environments is also studied. The best packet detection algorithm for the multi-band orthogonal frequency division multiplexing (MB-OFDM) UWB transmission is determined through analysis and extensive simulations. The results of analysis show that the proposed packet detection structure has advantages in the hardware complexity as well as performance when compared with the existing packet detection structures. In order to effectively conduct the packet detection before the automatic gain control (AGC) mode, we investigate the effects of both a frequency offset and the initial gain level of a variable gain amplifier (VGA) on the performance of the packet detection. We also suggest a VGA gain control technique to enhance the performance of packet detection.

Kang, Kyu-Min

315

Design and development of ultra-wideband 3 dB hybrid coupler for Ion cyclotron resonance frequency heating in tokamak  

NASA Astrophysics Data System (ADS)

Design and development of a high power ultra-wideband, 3 dB tandem hybrid coupler is presented and its application in ICRF heating of the tokamak is discussed. In order to achieve the desired frequency band of 38-112 MHz and 200 kW power handling capability, the 3 dB hybrid coupler is developed using two 3-element 8.34 ± 0.2 dB coupled lines sections in tandem. In multi-element coupled lines, junctions are employed for the joining of coupled elements that produce the undesirable reactance called junction discontinuity effect. The effect becomes prominent in the high power multi-element coupled lines for high frequency (HF) and very high frequency(VHF) applications because of larger structural dimensions. Junction discontinuity effect significantly deteriorates coupling and output performance from the theoretical predictions. For the analysis of junction discontinuity effect and its compensation, a theoretical approach has been developed and generalized for n-element coupled lines section. The theory has been applied in the development of the 3 dB hybrid coupler. The fabricated hybrid coupler has been experimentally characterized using vector network analyzer and obtained results are found in good agreement with developed theory.

Yadav, Rana Pratap; Kumar, Sunil; Kulkarni, S. V.

2014-04-01

316

Planar Differential Elliptical UWB Antenna Optimization  

Microsoft Academic Search

A recently proposed optimization procedure, based on the time domain characteristics of an antenna, is exploited to design a planar differential elliptical antenna for ultrawideband (UWB) applications. The optimization procedure aims at finding an antenna not only with low VSWR but also one exhibiting low-dispersion characteristics over the relevant frequency band. Furthermore, since in pulse communications systems the input signal

Nikolay Telzhensky; Yehuda Leviatan

2006-01-01

317

SA and SAR Analysis for Wearable UWB Body Area Applications  

NASA Astrophysics Data System (ADS)

With the rapid progress of electronic and information technology, an expectation for the realization of body area network (BAN) by means of ultra wide band (UWB) techniques has risen. Although the signal from a single UWB device is very low, the energy absorption may increase significantly when many UWB devices are simultaneously adorned to a human body. An analysis method is therefore required from the point of view of biological safety evaluation. In this study, two approaches, one is in the time domain and the other is in the frequency domain, are proposed for the specific energy absorption (SA) and the specific absorption rate (SAR) calculation. It is shown that the two approaches have the same accuracy but the time-domain approach is more straightforward in the numerical analysis. By using the time-domain approach, SA and SAR calculation results are given for multiple UWB pulse exposure to an anatomical human body model under the Federal Communications Commission (FCC) UWB limit.

Wang, Qiong; Wang, Jianqing

318

Generation and Radiation of UWB-signals  

Microsoft Academic Search

The most promising radiated UWB-signal is bipolar short one, like on sine cycle with time position modulation. The compromise between complexity, technology and compatibility is central frequency 2-5 GHz, which corresponds to short (<500 ps) pulse having 2-4 half periods at pulse repetition rate 10-100 MHz. Time position control should be down to 10 ps. Peak power reaches tens and

A. F. Kardo-Sysoev

2003-01-01

319

Generation and radiation of UWB-signals  

Microsoft Academic Search

The most promising radiated UWB-signal is bipolar short one, like one sine cycle with time position modulation. The compromise between complexity, technology and compatibility is central frequency 2-5 GHz, which corresponds to short (<500ps) pulse having 2-4 half periods at pulse repetition rate 10-100 MHz. time position control should be down to 10 ps. Peak power reaches tens and hundreds

A. F. Kardo-Sysoev

2003-01-01

320

A new communication system design of M-ary PPM UWB suitable to FCC signal spectrum  

NASA Astrophysics Data System (ADS)

UWB impulse radio signals have a very short duration, extremely wide bandwidth and share the same frequency spectrum with other existing systems. It was determined by the Federal Communications Commission (FCC) that UWB systems could cause interference with other systems, such as Global Positioning System (GPS) for example. Therefore, at present, the FCC has restricted the use of UWB systems to frequencies above 3.1 GHz. In this paper, we evaluated performance of UWB system using proposed pulses that are strictly limited in time to remove interference while, at the same time, contain their power distribution to a frequency band from 3.1 GHz to 10.6 GHz. In particular, we evaluated the BER Performance in relation to system parameters such as pulse duration, ?, the number of users, Nu, and the number of symbols, M. We found the optimal pulse duration ? through computer simulation using developed UWB pulses. It is shown that performance evaluation between the UWB communication system using these UWB pulses and the Gaussian monocycle pulse in M-ary PPM and BPSK schemes. These results can be contributed to construct M-ary PPM UWB communication system in terms of multiuser parameters and pulse duration.

Lee, Mike M.; Cho, Byung-Lok; Kim, Dae-Ik

2004-03-01

321

Intruder detection and tracking using UWB technology  

NASA Astrophysics Data System (ADS)

UWB communication is essentially the transmission and receiving of ultra short electromagnetic energy pulses. Short pulses mean wide bandwidths, often greatly exceeding 25% of the nominal center frequency. Modern UWB radio is characterized by very low power transmission (in the range of tens of microwatts) and wide bandwidths (greater than a gigahertz). One of the major applications of Ultra-wide band technology has been for detection and tracking of intruders in different environments. Based on some of our previous work [1,2] we developed a hybrid Ray-tracing/FDTD technique to study the indoor and outdoor propagation of UWB signals. The basic goal of this paper is to describe the experimental and simulation studies that were conducted to locate and track an intruder inside a UWB sensor web system. The sensor was developed using the Time Domain P-200 device and the software was developed using MATLAB. Return scans from UWB devices are analyzed to determine the noise floor and the signal strength. Using the noise floor level a threshold level is set above which the alarm will be triggered to determine the presence of an intruder. The probability of false alarm (PFA) is also determined using the Signal-to-Noise ratio and the threshold. We vary the PFA to lower the false alarm to a minimum level. We also determine the noise statistics of the system using Non-parametric Kolmogorov-Smirnov (KS) test. Using this basic UWB sensor web system we will try to determine the physical dimensions of the intruder and also track multiple intruders on the system.

Schiavone, Guy A.; Wahid, Parveen; Palaniappan, Ravishankar; Tracy, Judd; Vandoorn, Eric; Micikevicius, Paulis; Hughes, Charles

2004-08-01

322

A 128-channel 6 mW wireless neural recording IC with spike feature extraction and UWB transmitter.  

PubMed

This paper reports a 128-channel neural recording integrated circuit (IC) with on-the-fly spike feature extraction and wireless telemetry. The chip consists of eight 16-channel front-end recording blocks, spike detection and feature extraction digital signal processor (DSP), ultra wideband (UWB) transmitter, and on-chip bias generators. Each recording channel has amplifiers with programmable gain and bandwidth to accommodate different types of biological signals. An analog-to-digital converter (ADC) shared by 16 amplifiers through time-multiplexing results in a balanced trade-off between the power consumption and chip area. A nonlinear energy operator (NEO) based spike detector is implemented for identifying spikes, which are further processed by a digital frequency-shaping filter. The computationally efficient spike detection and feature extraction algorithms attribute to an auspicious DSP implementation on-chip. UWB telemetry is designed to wirelessly transfer raw data from 128 recording channels at a data rate of 90 Mbit/s. The chip is realized in 0.35 mum complementary metal-oxide-semiconductor (CMOS) process with an area of 8.8 x 7.2 mm(2) and consumes 6 mW by employing a sequential turn-on architecture that selectively powers off idle analog circuit blocks. The chip has been tested for electrical specifications and verified in an ex vivo biological environment. PMID:19435684

Chae, Moo Sung; Yang, Zhi; Yuce, Mehmet R; Hoang, Linh; Liu, Wentai

2009-08-01

323

A CPW-Fed Circular Wide-Slot UWB Antenna with Wide Tunable and Flexible Reconfigurable Dual Notch Bands  

PubMed Central

A coplanar waveguide (CPW)-fed circular slot antenna with wide tunable dual band-notched function and frequency reconfigurable characteristic is designed, and its performance is verified experimentally for ultra-wideband (UWB) communication applications. The dual band-notched function is achieved by using a T-shaped stepped impedance resonator (T-SIR) inserted inside the circular ring radiation patch and by etching a parallel stub loaded resonator (PSLR) in the CPW transmission line, while the wide tunable bands can be implemented by adjusting the dimensions of the T-SIR and the PSLR. The notch band reconfigurable characteristic is realized by integrating three switches into the T-SIR and the PSLR. The numerical and experimental results show that the proposed antenna has a wide bandwidth ranging from 2.7?GHz to 12?GHz with voltage standing wave ratio (VSWR) less than 2, except for the two notch bands operating at 3.8–5.9?GHz and 7.7–9.2?GHz, respectively. In addition, the proposed antenna has been optimized to a compact size and can provide omnidirectional radiation patterns, which are suitable for UWB communication applications. PMID:24222733

Li, Yingsong; Li, Wenxing; Ye, Qiubo

2013-01-01

324

Time-lapse imaging of human heart motion with switched array UWB radar.  

PubMed

Radar systems for detection of human heartbeats have mostly been single-channel systems with limited spatial resolution. In this paper, a radar system for ultra-wideband (UWB) imaging of the human heart is presented. To make the radar waves penetrate the human tissue the antenna is placed very close to the body. The antenna is an array with eight elements, and an antenna switch system connects the radar to the individual elements in sequence to form an image. Successive images are used to build up time-lapse movies of the beating heart. Measurements on a human test subject are presented and the heart motion is estimated at different locations inside the body. The movies show rhythmic motion consistent with the beating heart, and the location and shape of the reflections correspond well with the expected response form the heart wall. The spatial dependent heart motion is compared to ECG recordings, and it is confirmed that heartbeat modulations are seen in the radar data. This work shows that radar imaging of the human heart may provide valuable information on the mechanical movement of the heart. PMID:25350945

Brovoll, Sverre; Berger, Tor; Paichard, Yoann; Aardal, Øyvind; Lande, Tor Sverre; Hamran, Svein-Erik

2014-10-01

325

A Multiuser Detector Based on Artificial Bee Colony Algorithm for DS-UWB Systems  

PubMed Central

Artificial Bee Colony (ABC) algorithm is an optimization algorithm based on the intelligent behavior of honey bee swarm. The ABC algorithm was developed to solve optimizing numerical problems and revealed premising results in processing time and solution quality. In ABC, a colony of artificial bees search for rich artificial food sources; the optimizing numerical problems are converted to the problem of finding the best parameter which minimizes an objective function. Then, the artificial bees randomly discover a population of initial solutions and then iteratively improve them by employing the behavior: moving towards better solutions by means of a neighbor search mechanism while abandoning poor solutions. In this paper, an efficient multiuser detector based on a suboptimal code mapping multiuser detector and artificial bee colony algorithm (SCM-ABC-MUD) is proposed and implemented in direct-sequence ultra-wideband (DS-UWB) systems under the additive white Gaussian noise (AWGN) channel. The simulation results demonstrate that the BER and the near-far effect resistance performances of this proposed algorithm are quite close to those of the optimum multiuser detector (OMD) while its computational complexity is much lower than that of OMD. Furthermore, the BER performance of SCM-ABC-MUD is not sensitive to the number of active users and can obtain a large system capacity. PMID:23983638

Liu, Xiaohui

2013-01-01

326

Feasibility Study and Design of a Wearable System-on-a-Chip Pulse Radar for Contactless Cardiopulmonary Monitoring  

PubMed Central

A new system-on-a-chip radar sensor for next-generation wearable wireless interface applied to the human health care and safeguard is presented. The system overview is provided and the feasibility study of the radar sensor is presented. In detail, the overall system consists of a radar sensor for detecting the heart and breath rates and a low-power IEEE 802.15.4 ZigBee radio interface, which provides a wireless data link with remote data acquisition and control units. In particular, the pulse radar exploits 3.1–10.6 GHz ultra-wideband signals which allow a significant reduction of the transceiver complexity and then of its power consumption. The operating principle of the radar for the cardiopulmonary monitoring is highlighted and the results of the system analysis are reported. Moreover, the results obtained from the building-blocks design, the channel measurement, and the ultra-wideband antenna realization are reported. PMID:18389068

Zito, Domenico; Pepe, Domenico; Neri, Bruno; Zito, Fabio; De Rossi, Danilo; Lanatà, Antonio

2008-01-01

327

SSA realization for spectrum shaping and NBI suppression in cognitive UWB radios  

Microsoft Academic Search

This paper investigates spectrum shaping in ultrawideband (UWB) communications and introduces spectral nulls to limit interference with narrowband signals. In order to achieve the cognitive UWB radio, a design scheme for pulse waveform optimization based on prolate spheroidal wave functions (PSWF) has been investigated for producing the expected spectral notches while matching with the required spectral mask. We simulate the

Changguo Wu; Gangxing Jiang; Hongbo Zhu

2008-01-01

328

1-GHz Input Bandwidth Under-Sampling A/D Converter with Dynamic Current Reduction Comparator for UWB-IR Receiver  

NASA Astrophysics Data System (ADS)

A 1-GHz input bandwidth analog-to-digital (A/D) converter for an ultra-wideband impulse radio (UWB-IR) receiver is developed. Both an under-sampling sample-and-hold (S/H) circuit and a dynamic current-reduction comparator are proposed for the A/D converter. An under-sampling S/H circuit, which digitizes an input signal at a higher frequency than the sampling frequency with low power consumption, is required because the UWB-IR system utilizes intermittent ultrashort impulses. The proposed S/H circuit executes sampling by separating a sampling capacitor from an operational amplifier and accumulating the offset voltage of the amplifier in the other capacitor. The proposed dynamic current reduction comparator reduces bias current dynamically corresponding to its input-voltage level. The A/D converter is implemented in a 0.18-µm CMOS process technology, which achieves an effective number of bits of 5.5, 5.4, and 4.9 for input signals with frequencies of 1, 513, and 1057MHz, respectively, at 32M samples/s. The converter consumes 0.89mA and 0.42mA in the analog and digital component, respectively, at a 1.8-V supply.

Nakagawa, Tatsuo; Matsuura, Tatsuji; Imaizumi, Eiki; Kudoh, Junya; Ono, Goichi; Miyazaki, Masayuki

329

UWB channel estimation using new generating TR transceivers  

DOEpatents

The present invention presents a simple and novel channel estimation scheme for UWB communication systems. As disclosed herein, the present invention maximizes the extraction of information by incorporating a new generation of transmitted-reference (Tr) transceivers that utilize a single reference pulse(s) or a preamble of reference pulses to provide improved channel estimation while offering higher Bit Error Rate (BER) performance and data rates without diluting the transmitter power.

Nekoogar, Faranak (San Ramon, CA); Dowla, Farid U. (Castro Valley, CA); Spiridon, Alex (Palo Alto, CA); Haugen, Peter C. (Livermore, CA); Benzel, Dave M. (Livermore, CA)

2011-06-28

330

BER performance of implant-to-air high-speed UWB data communications for neural recording systems.  

PubMed

Implant-to-air ultra-wideband communication systems are interesting for neural recording systems due to their low power consumption and high data-rates. In this paper we investigate the performance of an implant-to-air wireless link using a realistic model of the biological channel for neural recording systems. We propose an optimized fifth-derivative Gaussian pulse as a transmitted waveform for different modulations: binary phase shift keying (BPSK), on-off keying (OOK) and differential phase shift keying (DPSK). Monitoring of neural responses with high resolution in the brain requires a high data rate link as the number of electrodes is increased. Each electrode needs a data rate around 800 kb/s to support its neural channel. As we target more than 512 electrodes, we require a data link higher than 400 Mbps. PMID:25570859

Bahrami, H; Mirbozorgi, S A; Rusch, L A; Gosselin, B

2014-08-01

331

SEMICONDUCTOR INTEGRATED CIRCUITS: A low jitter, low spur multiphase phase-locked loop for an IR-UWB receiver  

NASA Astrophysics Data System (ADS)

A low jitter, low spur multiphase phase-locked loop (PLL) for an impulse radio ultra-wideband (IR-UWB) receiver is presented. The PLL is based on a ring oscillator in order to simultaneously meet the jitter requirement, low power consumption and multiphase clock output. In this design, a noise and matching improved voltage-controlled oscillator (VCO) is devised to enhance the timing accuracy and phase noise performance of multiphase clocks. By good matching achieved in the charge pump and careful choice of the loop filter bandwidth, the reference spur is suppressed. A phase noise of -118.42 dBc/Hz at a frequency offset of 1 MHz, RMS jitter of 1.53 ps and reference spur of -66.81 dBc are achieved at a carrier frequency of 264 MHz in measurement. The chip was manufactured in 0.13 ?m CMOS technology and consumes 4.23 mW from a 1.2 V supply while occupying 0.14 mm2 area.

Ke, Shao; Hu, Chen; Yaohua, Pan; Zhiliang, Hong

2010-08-01

332

A Modified ?0/4 Short-Circuited Stub Bandpass Filter for UWB Applications Utilizing LTCC Technology  

NASA Astrophysics Data System (ADS)

In this paper, we utilize low temperature co-fired ceramic technology (LTCC) to realize a modified short-circuited stub bandpass filter suitable for ultra-wideband (UWB) applications. By modifying the conventional short-circuited stub bandpass filter structure with stubs and connecting lines of lower characteristic impedances, the number of stubs has been reduced from 5 to 2 on a high dielectric constant substrate (?r=40). A wireless local area network (WLAN) stopband in the frequency range of 5.15 to 5.825GHz has been inserted into the filter characteristic using three short-circuited coupled lines. The filter is fabricated and measurement results show that it has an insertion loss less than 1.0dB and return loss better than 10dB in the pass bands. A bandwidth ratio of 109.49% has been achieved. Measurement results agree well with simulation results. The dimensions of the filter are 4×8×0.57mm3.

Duong, Thai Hoa; Lee, Kye San; Kim, Ihn S.

333

Physically small and adjustable double-ridged horn antenna for biomedical UWB radar applications  

Microsoft Academic Search

Biomedical applications of ultra-wideband radar promise a very important means to remotely characterise tissues and organs. The acquisition of such physiological signatures requires small and efficient antennas, designed for ultra-wideband frequency operation. We have designed and characterised physically small and adjustable double-ridged horn antennas for frequencies from 1 to 10 GHz. The miniaturisation of the radiating elements was accomplished by

U. Schwarz; M. Helbig; J. Sachs; F. Seifert; R. Stephan; F. Thiel; M. A. Hein

2008-01-01

334

Aspects of ultrafast spark gap switching UWB HPM generation  

Microsoft Academic Search

The Air Force is interested in compact ultra-wideband systems which utilize a minimum volume of high pressure gas. These desires lead us to look closely at single channel spark gaps, because both the size and volume of gas, for example, hydrogen, under pressure can be much less than needed for sources containing ring gap switches. White single channel spark gap

J. M. Lehr; C. E. Baum; W. D. Prather; F. J. Agee

1997-01-01

335

Constrained maximum likelihood positioning for UWB based human motion tracking  

Microsoft Academic Search

In this paper, the problem of human motion tracking with ultra-wideband radio nodes is addressed. We provide a general maximum likelihood formulation of the positioning problem based on range measurements which can handle synchronous and asynchronous agents. Geometrical constraints on the node topology, which are imposed by the human body, are also taken into account. For a Gaussian ranging error

Zemene W. Mekonnen; Eric Slottke; Heinrich Luecken; Christoph Steiner; Armin Wittneben

2010-01-01

336

A RF receiver frontend for SC-UWB in a 0.18-?m CMOS process  

NASA Astrophysics Data System (ADS)

A radio frequency (RF) receiver frontend for single-carrier ultra-wideband (SC-UWB) is presented. The front end employs direct-conversion architecture, and consists of a differential low noise amplifier (LNA), a quadrature mixer, and two intermediate frequency (IF) amplifiers. The proposed LNA employs source inductively degenerated topology. First, the expression of input impedance matching bandwidth in terms of gate-source capacitance, resonant frequency and target S11 is given. Then, a noise figure optimization strategy under gain and power constraints is proposed, with consideration of the integrated gate inductor, the bond-wire inductance, and its variation. The LNA utilizes two stages with different resonant frequencies to acquire flat gain over the 7.1-8.1 GHz frequency band, and has two gain modes to obtain a higher receiver dynamic range. The mixer uses a double balanced Gilbert structure. The front end is fabricated in a TSMC 0.18-?m RF CMOS process and occupies an area of 1.43 mm2. In high and low gain modes, the measured maximum conversion gain are 42 dB and 22 dB, input 1 dB compression points are -40 dBm and -20 dBm, and S11 is better than -18 dB and -14.5 dB. The 3 dB IF bandwidth is more than 500 MHz. The double sideband noise figure is 4.7 dB in high gain mode. The total power consumption is 65 mW from a 1.8 V supply.

Rui, Guo; Haiying, Zhang

2012-12-01

337

FIR Filter of DS-CDMA UWB Modem Transmitter  

NASA Astrophysics Data System (ADS)

This letter presents low-complexity digital pulse shaping filter structures of a direct sequence code division multiple access (DS-CDMA) ultra wide-band (UWB) modem transmitter with a ternary spreading code. The proposed finite impulse response (FIR) filter structures using a look-up table (LUT) have the effect of saving the amount of memory by about 50% to 80% in comparison to the conventional FIR filter structures, and consequently are suitable for a high-speed parallel data process.

Kang, Kyu-Min; Cho, Sang-In; Won, Hui-Chul; Choi, Sang-Sung

338

UWB Dual-Polarized Antenna for HPEM Sources  

NASA Astrophysics Data System (ADS)

A novel dual-polarized exponential tapered slot antenna for high power electromagnetic (HPEM) sources is designed and verified. This antipodal version of an ultra-wideband Vivaldi antenna offers compact sizes and sustains high input power of about 40 kV. Gains of about 8 dBi can be achieved. Both antenna planes are isolated with more than 20 dB.

Schmitz, J.; Camp, M.; Jung, M.; Adamiuk, G.; Scherr, S.; Zwick, T.

339

Characteristics of trap-filled gallium arsenide photoconductive switches used in high gain pulsed power applications  

SciTech Connect

The electrical properties of semi-insulating (SI) Gallium Arsenide (GaAs) have been investigated for some time, particularly for its application as a substrate in microelectronics. Of late this material has found a variety of applications other than as an isolation region between devices, or the substrate of an active device. High resistivity SI GaAs is increasingly being used in charged particle detectors and photoconductive semiconductor switches (PCSS). PCSS made from these materials operating in both the linear and non-linear modes have applications such as firing sets, as drivers for lasers, and in high impedance, low current Q-switches or Pockels cells. In the non-linear mode, it has also been used in a system to generate Ultra-Wideband (UWB) High Power Microwaves (HPM). The choice of GaAs over silicon offers the advantage that its material properties allow for fast, repetitive switching action. Furthermore photoconductive switches have advantages over conventional switches such as improved jitter, better impedance matching, compact size, and in some cases, lower laser energy requirement for switching action. The rise time of the PCSS is an important parameter that affects the maximum energy transferred to the load and it depends, in addition to other parameters, on the bias or the average field across the switch. High field operation has been an important goal in PCSS research. Due to surface flashover or premature material breakdown at higher voltages, most PCSS, especially those used in high power operation, need to operate well below the inherent breakdown voltage of the material. The lifetime or the total number of switching operations before breakdown, is another important switch parameter that needs to be considered for operation at high bias conditions. A lifetime of {approximately} 10{sup 4} shots has been reported for PCSS's used in UWB-HPM generation [5], while it has exceeded 10{sup 8} shots for electro-optic drivers. Much effort is currently being channeled in the study related to improvements of these two parameters high bias operation and lifetime improvement for switches used in pulsed power applications. The contact material and profiles are another important area of study. Although these problems are being pursued through the incorporation of different contact materials and introducing doping near contacts, it is important that the switch properties and the conduction mechanism in these switches be well understood such that the basic nature of the problems can be properly addressed. In this paper the authors report on these two basic issues related to the device operation, i.e., mechanisms for increasing the hold-off characteristics through neutron irradiation, and the analysis of transport processes at varying field conditions in trap dominated SI GaAs in order to identify the breakdown mechanism during device operation. It is expected that this study would result in a better understanding of photoconductive switches, specifically those used in high power operation.

ISLAM,N.E.; SCHAMILOGLU,E.; MAR,ALAN; LOUBRIEL,GUILLERMO M.; ZUTAVERN,FRED J.; JOSHI,R.P.

2000-05-30

340

SSA realization in UWB multiple access systems based on prolate spheroidal wave functions  

Microsoft Academic Search

With respect to soft-spectrum adaptation (SSA) UWB wireless system with multiband pulse waveform shaping and adaptation, we investigate a design scheme for pulse waveform optimization based on prolate spheroidal wave functions (PSWF). The PSWF-based pulse shaping is then applied to M-ary signaling for high data rate and multiple accessing environment expected by multiuser services. Moreover, double water-filling (DWF) method is

Honggang Zhang; Ryuji KOHNO

2004-01-01

341

Impulse radio multipath characteristics and diversity reception  

Microsoft Academic Search

Delay-and-sum beamforming is applied to both ideal and measured ultra-wideband (UWB) signals. The results of propagation measurements are also used directly to estimate the performance of an UWB communication system and to characterize design tradeoffs

R. Jean-Marc Cramer; Moe Z. Win; Robert A. Scholtz

1998-01-01

342

UWB doublet generation using nonlinearly-biased electro-optic intensity modulator  

E-print Network

-optic intensity modulator (EOM) is proposed and experimentally demonstrated. The EOM is biased at a nonlinear to the EOM, the pedestal or the peak part of the pulse is inverted, leading to the generation of a UWB that uses only a single electro- optic intensity modulator (EOM). The fundamental principle is to shape

Yao, Jianping

343

Coded N-ary PPM UWB impulse radio with chaotic time hopping and polarity  

E-print Network

, S.-Y. Jin and H.-Y. Song A coded N-ary pulse position modulated (PPM) ultra-wide bandwidth (UWB hopping (TH) ultra-wide band- width (UWB) impulse radio (IR) communications. A pseudo chaotic time hopping is given by mk;u ¼ ðkTf þðuþ1=2�Ts kTf þðu�1=2�Ts rðt� � wðt � kTf � uTs�dt ð2� A vector mk ¼ ðmk;0; mk;1

Song, Hong-Yeop

344

MIMO-UWB propagation channels  

Microsoft Academic Search

The use of ultra-wide bandwidth, while keeping a low power spectral density, is a promising approach for high-data rate communications as well as low-power communications and geolocation. The use of multiple antenna elements at transmitter and receiver (MIMO) can further increase data rate, system robustness, and precision of localization. The ultimate performance of MIMO-UWB systems is determined by the propagation

Andreas F. Molisch

2010-01-01

345

Generation of Power-Efficient FCC-Compliant UWB Waveforms Using FBGs: Analysis and Experiment  

Microsoft Academic Search

In this paper, we design, analyze, and demonstrate experimentally U.S. Federal Communications Commission (FCC)- compliant power-efficient ultrawideband (UWB) waveforms generated by optical pulse shaping. The time-domain pulse shape is written in the frequency domain, and a single-mode fiber performs the frequency-to-time conversion. The waveform is inscribed in the frequency domain by the fiber Bragg grating (FBG). A significant challenge for

Mohammad Abtahi; Julien Magne; Mehrdad Mirshafiei; Leslie A. Rusch; Sophie Larochelle

2008-01-01

346

ULTRA WIDEBAND ROSE LEAF MICROSTRIP PATCH ANTENNA  

Microsoft Academic Search

In this paper a novel rose leaf shape microstrip antenna with capacitively coupled rectangular fed is presented.Various shapes of capacitive coupled fed are compared and optimized by successive iterations of a computer-aided analysis.The Ansoft HFSS is employed for analysis at the frequency band of 4.3 GHz-8.3 GHz. The antenna is fabricated and measurement results show a very good agreement with

Abbas Ali Lotfi Neyestanak; Shahre Rey Branch

2008-01-01

347

Ultra-Wideband Digital Receiver LNA Design  

E-print Network

output SNR, which is defined as the matched filter bound. ­ Applies equally to broadband and narrowband power dissipation. #12;Existing Work · Narrowband matching. ­ Single-tone assumption. · NF = (output on signal and noise spectrum. · SNR defined as the matched filter bound. ­ Whitened matched filter for one

Southern California, University of

348

Ultra-wideband tomography of land cover  

NASA Astrophysics Data System (ADS)

This paper describes a comprehensive approach which combines the application of OKO-2 ground penetrating radar, conventional method of cross sectioning accepted in edaphology, soil-testing parameters, mobile and laboratory research of dielectric permittivity for stratified soil cover research. Dielectric characteristics measurements of selected contact samples by the waveguide-coaxial technique showed a correlation between electrophysic characteristics of soil with soil moisture and density. Location of deep aquifers was detected and the real local topography was restored. Research was performed within the Timiryazevskoye forest district near Tomsk. Comparing the results of radar non-destructive sounding and contact measurements demonstrated high correlation of detected structural soil features. The suggested approach provides a solid basis for verifying the non-contact radiophysical methods of research in the interests of rational nature management and land utilization.

Kochetkova, Tatiana D.; Zapasnoy, Andrey S.; Klokov, Andrey V.; Shipilov, Sergey E.; Yakubov, Vladimir P.; Yurchenko, Alexey V.

2014-11-01

349

Time-of-arrival estimation by UWB radios with low sampling rate and clock drift calibration$  

E-print Network

: Ultra-wideband Time-of-arrival Clock drift Stroboscopic sampling a b s t r a c t In this paper, we is featured by a low sampling rate and is robust against clock drift. Low-rate stroboscopic sampling, which samples, the clock drift is one of the main error sources in TOA estimation with stroboscopic sampling IR

Leus, Geert

350

Coarse synchronization of UWB signals in the dense multipath channel based on the golden section  

Microsoft Academic Search

In this paper we address the problem of coarse synchronization of ultra wideband signals in the dense multipath channel, following the widely used hypothesis testing approach in which the uncertainty region for the timing offset is divided into a certain number of cells. We propose a novel strategy for the search of the correct cells, within the constant increment perspective.

Eva Arias-de-Reyna; José I. Acha-Catalina

2007-01-01

351

Improving link quality of UWB communication links by means of PSWF-Basis persuit denoising  

Microsoft Academic Search

Wireless Body Area Networks (WBANs) utilising Ultra Wideband communication channels often use a combina- tion of thin sensor nodes and a heavy base node. The sensor nodes need to be as simple and low power as possible. This makes it difficult to maintain a good quality link. In this paper additional post processing steps at the base node are proposed

Wouter Dullaert; Hendrik Rogier; Luca De Camillis; Tom Dhaene

2011-01-01

352

Design and implementation of a digital impulse generator for a 24GHz UWB radar  

NASA Astrophysics Data System (ADS)

In this paper, we design and implement a digital impulse generator using a DCM block and an OSERDES block for a 24GHz UWB impulse-Doppler radar. The Federal Communications Commission (FCC) has confirmed the spectrum from 22 to 29GHz for UWB radar with a limit power of -41.3dBm/MHz. UWB signal possesses an absolute bandwidth larger than 500MHz or a relative bandwidth up to 20%. The vehicle radar is the key technology with the inherent advantage detected the distance and the velocity regardless of weather. Radar has a role to measure the distance and the velocity of long-distance vehicle. But, the radar with 1m resolution is difficult to satisfy the detection performance in the blind spot zone because the blind spot zone needs high resolution. So, UWB impulse-Doppler radar with 30cm resolution is suitable for the blind spot zone. The designed impulse generator has a 2ns pulse width and 100us PRI. We perform simulations through Xilinx ISE; experiments use a spectrum analyzer and a digital oscilloscope. For UWB radar, we use an AD9779 DAC module with a 1Gsps maximum sampling rate. For equipment, we use a TDS5104B oscilloscope of Tektronix with 3dB bandwidth at 1GHz for the analysis of the time domain and an E4448A spectrum analyzer of Agilent with a 50GHz spectrum for the analysis of the frequency domain. The results of the digital impulse measurement show a 2ns pulse width in the time domain, a 500MHz bandwidth, and a 10KHz spectrum peak in the frequency domain.

Kim, Sang-Dong; Lee, Jong-Hun

2011-06-01

353

WCNC 2002WCNC 2002 UWB Radio: PresentUWB Radio: Present  

E-print Network

Block Painted 2X6 Board Clay Brick 3/4" Plywood 3/4" Pine Board Wet Paper Towel Glass Drywall Asphalt Shingle TotalOneWayAttenuation(dB) Kevlar Sheet Polyethylene Paper Towel (Dry) Fiberglass Insul. See: L. MUltRa Lab WCNC 2002WCNC 2002 UWB Radio: PresentUWB Radio: Present Challenges,Challenges, Future

Southern California, University of

354

A Low Complex Frequency Domain Nondata-Aided Channel Estimation for Indoor Time-Hopping UWB Communication System  

Microsoft Academic Search

This paper proposes a low complex frequency domain channel estimation for ultra-wideband indoor environment. The channel parameters are the attenuations and delays incurred by the signal echoes along the propagation paths. Time-hopping (TH) modulation with binary symbols is assumed. Codewords span a transmission frame. Frames are separated by a guard time to cope with the channel time dispersion. The estimation

Long Zhao; Chenglin Zhao; Zheng Zhou; Peng Lu

2006-01-01

355

Non-Invasive UWB Sensing of Astronauts' Breathing Activity.  

PubMed

The use of a UWB system for sensing breathing activity of astronauts must account for many critical issues specific to the space environment. The aim of this paper is twofold. The first concerns the definition of design constraints about the pulse amplitude and waveform to transmit, as well as the immunity requirements of the receiver. The second issue concerns the assessment of the procedures and the characteristics of the algorithms to use for signal processing to retrieve the breathing frequency and respiration waveform. The algorithm has to work correctly in the presence of surrounding electromagnetic noise due to other sources in the environment. The highly reflecting walls increase the difficulty of the problem and the hostile scenario has to be accurately characterized. Examples of signal processing techniques able to recover breathing frequency in significant and realistic situations are shown and discussed. PMID:25558995

Baldi, Marco; Cerri, Graziano; Chiaraluce, Franco; Eusebi, Lorenzo; Russo, Paola

2014-01-01

356

Photonic generation of ultrawideband pulse using semiconductor laser with optical feedback.  

PubMed

We propose and demonstrate an approach to the generation of an ultrawideband (UWB) pulse utilizing the nonlinear dynamics of a semiconductor laser (SL). The output UWB chaotic optical pulses generated by the SL with optical feedback can be controlled when the feedback strength and driving current of the SL are tuned. Our experiment proves that the spectrum characteristics of the UWB pulses satisfy Federal Communications Commission regulations, and the experimental results are consistent with the simulated results based on the laser's rate equations. PMID:20517398

Zheng, Jian-Yu; Zhang, Ming-Jiang; Wang, An-Bang; Wang, Yun-Cai

2010-06-01

357

Antennas for the Detection of Radio Emission Pulses from Cosmic-Ray induced Air Showers at the Pierre Auger Observatory  

E-print Network

The Pierre Auger Observatory is exploring the potential of the radio detection technique to study extensive air showers induced by ultra-high energy cosmic rays. The Auger Engineering Radio Array (AERA) addresses both technological and scientific aspects of the radio technique. A first phase of AERA has been operating since September 2010 with detector stations observing radio signals at frequencies between 30 and 80 MHz. In this paper we present comparative studies to identify and optimize the antenna design for the final configuration of AERA consisting of 160 individual radio detector stations. The transient nature of the air shower signal requires a detailed description of the antenna sensor. As the ultra-wideband reception of pulses is not widely discussed in antenna literature, we review the relevant antenna characteristics and enhance theoretical considerations towards the impulse response of antennas including polarization effects and multiple signal reflections. On the basis of the vector effective l...

Abreu, P; Ahlers, M; Ahn, E J; Albuquerque, I F M; Allard, D; Allekotte, I; Allen, J; Allison, P; Almela, A; Castillo, J Alvarez; Alvarez-Muñiz, J; Batista, R Alves; Ambrosio, M; Aminaei, A; Anchordoqui, L; Andringa, S; Anti?i?, T; Aramo, C; Arganda, E; Arqueros, F; Asorey, H; Assis, P; Aublin, J; Ave, M; Avenier, M; Avila, G; Badescu, A M; Balzer, M; Barber, K B; Barbosa, A F; Bardenet, R; Barroso, S L C; Baughman, B; Bäuml, J; Baus, C; Beatty, J J; Becker, K H; Bellétoile, A; Bellido, J A; BenZvi, S; Berat, C; Bertou, X; Biermann, P L; Billoir, P; Blanco, F; Blanco, M; Bleve, C; Blümer, H; Boh\\'{?ová, M; Boncioli, D; Bonifazi, C; Bonino, R; Borodai, N; Brack, J; Brancus, I; Brogueira, P; Brown, W C; Bruijn, R; Buchholz, P; Bueno, A; Buroker, L; Burton, R E; Caballero-Mora, K S; Caccianiga, B; Caramete, L; Caruso, R; Castellina, A; Catalano, O; Cataldi, G; Cazon, L; Cester, R; Chauvin, J; Cheng, S H; Chiavassa, A; Chinellato, J A; Diaz, J Chirinos; Chudoba, J; Cilmo, M; Clay, R W; Cocciolo, G; Collica, L; Coluccia, M R; Conceição, R; Contreras, F; Cook, H; Cooper, M J; Coppens, J; Cordier, A; Coutu, S; Covault, C E; Creusot, A; Criss, A; Cronin, J; Curutiu, A; Dagoret-Campagne, S; Dallier, R; Daniel, B; Dasso, S; Daumiller, K; Dawson, B R; de Almeida, R M; De Domenico, M; De Donato, C; de Jong, S J; De La Vega, G; Junior, W J M de Mello; Neto, J R T de Mello; De Mitri, I; de Souza, V; de Vries, K D; del Peral, L; del Río, M; Deligny, O; Dembinski, H; Dhital, N; Di Giulio, C; Castro, M L Díaz; Diep, P N; Diogo, F; Dobrigkeit, C; Docters, W; D'Olivo, J C; Dong, P N; Dorofeev, A; Anjos, J C dos; Dova, M T; D'Urso, D; Dutan, I; Ebr, J; Engel, R; Erdmann, M; Escobar, C O; Espadanal, J; Etchegoyen, A; Luis, P Facal San; Falcke, H; Farrar, G; Fauth, A C; Fazzini, N; Ferguson, A P; Fick, B; Figueira, J M; Filevich, A; Filip?i?, A; Fliescher, S; Fracchiolla, C E; Fraenkel, E D; Fratu, O; Fröhlich, U; Fuchs, B; Gaior, R; Gamarra, R F; Gambetta, S; García, B; Roca, S T Garcia; Garcia-Gamez, D; Garcia-Pinto, D; Bravo, A Gascon; Gemmeke, H; Ghia, P L; Giller, M; Gitto, J; Glass, H; Gold, M S; Golup, G; Albarracin, F Gomez; Berisso, M Gómez; Vitale, P F Gómez; Gonçalves, P; Gonzalez, J G; Gookin, B; Gorgi, A; Gouffon, P; Grashorn, E; Grebe, S; Griffith, N; Grigat, M; Grillo, A F; Guardincerri, Y; Guarino, F; Guedes, G P; Hansen, P; Harari, D; Harrison, T A; Harton, J L; Haungs, A; Hebbeker, T; Heck, D; Herve, A E; Hojvat, C; Hollon, N; Holmes, V C; Homola, P; Hörandel, J R; Horvath, P; Hrabovský, M; Huber, D; Huege, T; Insolia, A; Ionita, F; Italiano, A; Jansen, S; Jarne, C; Jiraskova, S; Josebachuili, M; Kadija, K; Kampert, K H; Karhan, P; Kasper, P; Katkov, I; Kégl, B; Keilhauer, B; Keivani, A; Kelley, J L; Kemp, E; Kieckhafer, R M; Klages, H O; Kleifges, M; Kleinfeller, J; Knapp, J; Koang, D -H; Kotera, K; Krohm, N; Krömer, O; Kruppke-Hansen, D; Kuempel, D; Kulbartz, J K; Kunka, N; La Rosa, G; Lachaud, C; LaHurd, D; Latronico, L; Lauer, R; Lautridou, P; Coz, S Le; Leão, M S A B; Lebrun, D; Lebrun, P; de Oliveira, M A Leigui; Letessier-Selvon, A; Lhenry-Yvon, I; Link, K; López, R; Agüera, A Lopez; Louedec, K; Bahilo, J Lozano; Lu, L; Lucero, A; Ludwig, M; Lyberis, H; Maccarone, M C; Macolino, C; Maldera, S; Maller, J; Mandat, D; Mantsch, P; Mariazzi, A G; Marin, J; Marin, V; Maris, I C; Falcon, H R Marquez; Marsella, G; Martello, D; Martin, L; Martinez, H; Bravo, O Martínez; Martraire, D; Meza, J J Masías; Mathes, H J; Matthews, J; Matthews, J A J; Matthiae, G; Maurel, D; Maurizio, D; Mazur, P O; Medina-Tanco, G; Melissas, M; Melo, D; Menichetti, E; Menshikov, A; Mertsch, P; Meurer, C; Meyhandan, R; Mi?anovi?, S; Micheletti, M I; Minaya, I A; Miramonti, L; Molina-Bueno, L; Mollerach, S; Monasor, M; Ragaigne, D Monnier; Montanet, F; Morales, B; Morello, C; Moreno, E; Moreno, J C; Mostafá, M; Moura, C A; Muller, M A; Müller, G; Münchmeyer, M; Mussa, R; Navarra, G; Navarro, J L; Navas, S; Necesal, P; Nellen, L; Nelles, A; Neuser, J; Nhung, P T; Niechciol, M; Niemietz, L; Nierstenhoefer, N; Nitz, D; Nosek, D; Nožka, L; Oehlschläger, J; Olinto, A; Ortiz, M; Pacheco, N; Selmi-Dei, D Pakk; Palatka, M; Pallotta, J; Palmieri, N; Parente, G; Parizot, E; Parra, A; Pastor, S; Paul, T; Pech, M; P?kala, J; Pelayo, R; Pepe, I M; Perrone, L; Pesce, R; Petermann, E; Petrera, S; Petrolini, A; Petrov, Y; Pfendner, C; Piegaia, R; Pierog, T; Pieroni, P; Pimenta, M; Pirronello, V; Platino, M; Plum, M; Ponce, V H; Pontz, M; Porcelli, A; Privitera, P; Prouza, M; Quel, E J; Querchfeld, S; Rautenberg, J; Ravel, O; Ravignani, D; Revenu, B; Ridky, J; Riggi, S; Risse, M; Ristori, P; Rivera, H; Rizi, V; Roberts, J; de Carvalho, W Rodrigues; Rodriguez, G; Cabo, I Rodriguez; Martino, J Rodriguez; Rojo, J Rodriguez; Rodríguez-Frías, M D; Ros, G; Rosado, J

2012-01-01

358

Performance of UWB-Impulse Radio Receiver Based on Matched Filter Implementation with Imperfect Channel Estimation  

NASA Astrophysics Data System (ADS)

UWB communications have attracted considerable interest, targeting applications in high-speed data transfer wireless communication systems. This paper studies the effects of matched filter receiver in the performance of such a system. Such effects are evaluated in terms of the Bit Error Rate (BER) for a Binary Pulse Position Modulation (BPPM) scheme, considering multipath propagation channel and the presence of noise. The case of imperfect channel estimation is taken into account. Dependence of BER on parameters such as signal to noise ratio, number of estimation pulses and correletor taps is also presented.

Tatsis, Giorgos; Votis, Constantinos; Raptis, Vasilis; Christofilakis, Vasilis; Chronopoulos, Spyridon K.; Kostarakis, Panos

2010-01-01

359

Design and Implementation of Energy-Collection-Based Low Complexity IR-UWB Receiver  

NASA Astrophysics Data System (ADS)

In this paper, an energy-collection-based non-coherent IR-UWB receiver allowing low complexity and low power consumption is proposed for short range data communication. The proposed receiver consists of an on-the-fly integrator, a 1-bit digital sampler, a pre-processor and a digital symbol synchronizer. The on-the-fly integrator for energy collection and the 1-bit digital sampler reduce complexity of IR-UWB system. Furthermore, with a simple digital filter in the pre-processing unit, SNR and robustness of the receiver against time-varying channel are enhanced. Also the receiver complexity is diminished by a simple scheme of symbol synchronization based on rough time information about incoming pulses, not requiring exact timing information. The performance of the proposed receiver is simulated based on IEEE 802. 15. 4a channel model and the algorithms are implemented and verified on a FPGA.

Lee, Soon-Woo; Park, Young-Jin; Kim, Kwan-Ho

360

Asymmetrically-loaded interdigital coupled line for wideband microstrip bandpass filters  

E-print Network

at least twice. Very recently, this three coupled-line structure in the format of an interdigital capacitor has been employed to constitute an ultra-wideband (UWB) bandpass filter [5]. Moreover, by extending

Leung, Ka-Cheong

361

Frequency-aware rate adaptation and MAC protocol  

E-print Network

There has been burgeoning interest in wireless technologies that can use wider frequency spectrum. Technology advances, such as 802.11n and ultra-wideband (UWB), are pushing toward wider frequency bands. The analog-to-digital ...

Rahul, Hariharan Shankar

362

Distributed MAC protocol for networks with multipacket reception capability and spatially distributed nodes  

E-print Network

The physical layer of future wireless networks will be based on novel radio technologies such as Ultra-Wideband (UWB) and Multiple-Input Multiple-Output (MIMO). One of the important capabilities of such technologies is the ...

Celik, Guner Dincer

2007-01-01

363

Photoinjector-driven chirped-pulsed free electron maser  

NASA Astrophysics Data System (ADS)

An ultra-short pulse, millimeter-wave free electron maser experiment is currently underway at UC Davis and Lawrence Livermore National Laboratory. A 8.5 kG, 30 mm period helical wiggler is used to transversally accelerate a train of one hundred 5 MeV, 0.25 nC, 1 ps duration micro bunches synchronously energized by a 20 MW, X-band photocathode RF linac. The photocathode is irradiated by a burst-mode, UV laser system which produces up to 100 pulses at 207 nm, with an energy of 10 mJ/pulse, and a pulse duration of 200 fs, at a repetition rate of 2.142 GHz. This system includes a 400 fs jitter synchronously modelocked AlGaAs semiconductor laser oscillator which is amplified by an eight-pass Ti:Al2O3 chirped pulse laser amplifier. The output of this amplifier is subsequently frequency quadrupled into the UV. Because the electron micro bunches are shorter than the radiation wavelength, the system coherently synchrotron radiates and behaves essentially as a prebunched FEM. In addition, by operating in a waveguide structure at grazing, where the bunch axial velocity in the wiggler matches the group velocity of the electromagnetic waves, one obtains output radiation pulses which are extremely short, and have greatly enhanced peak power. The device operates in the TE(sub 12) mode of a cylindrical waveguide, and will produce up to 2 MW of coherent synchrotron radiation power at 140 GHz, in a 15 ps FWHM pulse. The -3 dB instantaneous interaction bandwidth extends from 125 GHz to 225 GHz. The output pulse is chirped over the full interaction bandwidth. One of the major potential applications of such a device is an ultra-wideband millimeter-wave radar.

Lesage, G. P.; Hartemann, F. V.; Feng, H. X. C.; Fochs, S. N.; Heritage, J. P.; Luhmann, N. C., Jr.; Perry, M. D.; Westenskow, G. A.

1995-03-01

364

Ranging detection algorithm for indoor UWB channels  

E-print Network

. · Analyze the UWB ranging performance in indoor environment and use the analysis to facilitate the ranging and Analysis 1 2 3 4 5 6 7 8 9 10 11 12 -160 -140 -120 -100 -80 -60 -40 Frequency (GHz) Power;14 -- CDF of ranging errors |CDF of ranging errors ||| 0 0.02 0.04 0.06 0.08 0 0.2 0.4 0.6 0.8 1 || (m

Southern California, University of

365

Simulative research on generating UWB signals by all-optical BPF  

NASA Astrophysics Data System (ADS)

The simulating technique is used to investigate generating and distributing Ultra-Wide-Band signals depend on fiber transmission. Numerical result for the system about the frequency response shows that the characteristics of band-pass filter is presented, and the shorter the wavelength is, the bandwidth of lower frequency is wider. Transmission performance simulation for 12.5Gb/s psudo-random sequence also shows that Gaussian pulse signal after transported in fiber is similar to UWB wave pattern mask of FCC in time domain and frequency spectrum specification of FCC in frequency domain .

Yang, Chunyong; Hou, Rui; Chen, Shaoping

2007-11-01

366

Power-efficient impulse radio ultrawideband pulse generator based on the linear sum of modified doublet pulses.  

PubMed

We propose a new and power-efficient impulse radio ultawideband (IR-UWB) pulse design concept. The proposed concept is based on a linear sum of modified doublet pulses. The proposed concept is both simulated and experimentally demonstrated. The experimental demonstration employs a photonic scheme that generates the designed pulse using two main steps, mainly optical shaping and differential detection. The optical shaping is performed using a single electro-optic modulator biased in the nonlinear portion of its transfer function, and the differential detection is performed using a balanced photodetector. The generated IR-UWB pulse is fully Federal Communications Commission compliant, even in the highly power-restricted global positioning system band. The proposed optical scheme has potential to be integrated on a compact optical chip and thus suitable for reliable, low-cost, high-speed, short-range UWB wireless access, such as in-building networks. PMID:21686021

Abraha, S T; Okonkwo, C M; Tangdiongga, E; Koonen, A M J

2011-06-15

367

Development of UWB, dual-polarized dielectric horn antenna (DHA) for UWB applications  

Microsoft Academic Search

A novel UWB dual-polarized dielectric horn antenna (DHA) is presented. A DHA consists of four major components - launcher, solid dielectric horn body, feeding structure and background absorber material. The characteristics of this DHA design have been investigated in detail via experiments and FDTD models. This new design is found to provide the desired ultrawide bandwidth, dual-linear polarization, frequency independent

Kwan-Ho Lee; Chi-Chih Chen; Roben Lee

2004-01-01

368

Breakdown Behavior of a Wireless Communication Network Under UWB Impact  

NASA Astrophysics Data System (ADS)

Systems with high priority to safety and reliability such as monitoring systems on airports have to work properly. Fast information transmission, continuous access to databases, as well as the management of air traffic are most important for effective and safe operation. Sources of Intentional Electromagnetic Interference can be manufactured relatively easy using commercially available components by civilian persons with relevant expertise and can be used for sabotage or blackmail purposes. For analyzing the weak points of a system existing on airports, it is necessary to reproduce its setup. In this investigation a UHF transmitter of a wireless communication device is developed and its breakdown behavior to unipolar fast rise pulses (UWB) is determined. A breakdown is a non-permanent damage, but includes a type of upset, that requires manual reset or at least stops communications for some period of time. The transmitter consists of three main components connected by data cables: power supply, microcontroller, and loop antenna. The immunity tests are accomplished as a function of the electromagnetic field direction to the device using an open TEM waveguide.

Rohe, M.; Koch, M.

369

UWB radar technique for arc detection in coaxial cables and waveguides  

NASA Astrophysics Data System (ADS)

As spread spectrum technology has revolutionized the communications industry, Ultra Wide Band (UWB) technology is dramatically improving radar performances. These advanced signal processing techniques have been adapted to coaxial cables and waveguides to provide new features and enhanced performance on arc detection. UWB signals constituted by a sequence of chips (properly chosen to reduce side lobes and to improve detection accuracy) are transmitted along the transmission lines at a specified Pulse Repetition Frequency (PRF) and their echoes are received by means of directional couplers. The core of the receiver is an ultra high-speed correlator implemented in a Digital Signal Processor (DSP). When a target (arc) is detected, its position and its "radar cross section" are calculated to be able to provide the arc position along the transmission line and to be able to classify the type of detected arc. The "background scattering" is routinely extracted from the received signal at any pulse. This permits to be resilient to the background structure of transmission lines (bends, junctions, windows, etc.). Thanks to the localization feature, segmentation is also possible for creating sensed and non-sensed zones (for example, to be insensitive to antenna load variations).

Maggiora, R.; Salvador, S.

2009-11-01

370

UWB radar technique for arc detection in coaxial cables and waveguides  

SciTech Connect

As spread spectrum technology has revolutionized the communications industry, Ultra Wide Band (UWB) technology is dramatically improving radar performances. These advanced signal processing techniques have been adapted to coaxial cables and waveguides to provide new features and enhanced performance on arc detection. UWB signals constituted by a sequence of chips (properly chosen to reduce side lobes and to improve detection accuracy) are transmitted along the transmission lines at a specified Pulse Repetition Frequency (PRF) and their echoes are received by means of directional couplers. The core of the receiver is an ultra high-speed correlator implemented in a Digital Signal Processor (DSP). When a target (arc) is detected, its position and its 'radar cross section' are calculated to be able to provide the arc position along the transmission line and to be able to classify the type of detected arc. The 'background scattering' is routinely extracted from the received signal at any pulse. This permits to be resilient to the background structure of transmission lines (bends, junctions, windows, etc.). Thanks to the localization feature, segmentation is also possible for creating sensed and non-sensed zones (for example, to be insensitive to antenna load variations)

Maggiora, R.; Salvador, S. [Politecnico di Torino, Department of Electronics, Torino (Italy)

2009-11-26

371

A CMOS variable gain LNA for UWB receivers  

NASA Astrophysics Data System (ADS)

A CMOS variable gain low noise amplifier (LNA) is presented for 4.2-4.8 GHz ultra-wideband application in accordance with Chinese standard. The design method for the wideband input matching is presented and the low noise performance of the LNA is illustrated. A three-bit digital programmable gain control circuit is exploited to achieve variable gain. The design was implemented in 0.13-?m RF CMOS process, and the die occupies an area of 0.9 mm2 with ESD pads. Totally the circuit draws 18 mA DC current from 1.2 V DC supply, the LNA exhibits minimum noise figure of 2.3 dB, S(1,1) less than -9 dB and S(2,2) less than -10 dB. The maximum and the minimum power gains are 28.5 dB and 16 dB respectively. The tuning step of the gain is about 4 dB with four steps in all. Also the input 1 dB compression point is -10 dBm and input third order intercept point (IIP3) is -2 dBm.

Feihua, Chen; Lingyun, Li; Xinzhong, Duo; Tong, Tian; Xiaowei, Sun

2011-02-01

372

Low-power impulse UWB architectures and circuits  

E-print Network

Ultra-wide-band (UWB) communication has a variety of applications ranging from wireless USB to radio frequency (RF) identification tags. For many of these applications, energy is critical due to the fact that the radios ...

Chandrakasan, Anantha P.

373

Compact Tapered Slot Antennas for UWB microwave imaging applications  

Microsoft Academic Search

This paper presents the design of compact Tapered Slot Antennas (TSAs) for application in an Ultra Wide Band (UWB) microwave imaging system. In the initial step, a conventional size-reduced TSA with an exponential taper for 3.1–10.6 GHz band is designed. From the radiation pattern analysis, it is found that this antenna exhibits poor directivity in the lower part of UWB.

Yifan Wang; Aslina Abu Bakar; Marek E. Bialkowski

2010-01-01

374

Imaging of Distributed Objects in UWB Sensor Networks  

NASA Astrophysics Data System (ADS)

The chapter proposes a new imaging algorithm. This algorithm is suitable for the imaging of extended objects in UWB sensor networks. Its comparison to the conventional range migration algorithm known from GPR or similar applications is given by a simulated example. The example shows disadvantages of the range migration algorithm for imaging in UWB sensor networks. Images obtained by the new proposed algorithm are easier to interpret and their quality is much higher.

Zetik, R.; Thomä, R. S.

375

2-Dimensional Imaging of Human Bodies with UWB Radar Using Approximately Uniform Walking Motion along a Straight Line with the SEABED Algorithm  

NASA Astrophysics Data System (ADS)

UWB (Ultra Wide-Band) pulse radar is a promising candidate for surveillance systems designed to prevent crimes and terror-related activities. The high-speed SEABED (Shape Estimation Algorithm based on BST and Extraction of Directly scattered waves) imaging algorithm, is used in the application of UWB pulse radar in fields that require realtime operations. The SEABED algorithm assumes that omni-directional antennas are scanned to observe the scattered electric field in each location. However, for surveillance systems, antenna scanning is impractical because it restricts the setting places of the devices. In this paper, movement of a body is used to replace antenna scanning. The instantaneous velocity of any given motion is an unknown variable that changes as a function of time. A pair of antennas is used to analyze delay time to estimate the unknown motion. We propose a new algorithm to estimate the shape of a human body using data obtained from a human body passing stationary antennas.

Sakamoto, Takuya; Sato, Toru

376

UWB and 60-GHz RF generation and transmission over WDM-PON based on bidirectional asymmetric polarization modulation and frequency multiplication  

NASA Astrophysics Data System (ADS)

A novel scheme to simultaneously provide UWB, 60-GHz millimeter-wave (mmW), and baseband services over a wavelength division multiplexing (WDM) passive optical network (PON) is proposed and demonstrated. In the proposed system, an OOK Gaussian pulse signal is modulated on the optical carrier and then converted to an OOK UWB impulse signal at an edge filter, a baseband signal and a 30-GHz signal are then modulated on the same optical carrier. By employing polarization multiplex technique, the UWB and baseband signal will have orthogonal polarization directions and the spectrum interference between the two signals is avoided. By suppressing the optical carrier, a frequencydoubled mmW signal at 60 GHz is generated by beating the two 1st order sidebands at a photodetector (PD). Error-free transmission of a UWB signal at 2.5 Gbps and a wired baseband signal at 2.5 and 5 Gbps over a 25-km single-mode fiber (SMF) is achieved. A frequency-doubled mmW signal at 60 GHz is also obtained.

Liu, Weilin; Yao, Jianping

2013-10-01

377

A 10 GS/s Distributed Waveform Generator for Sub-Nanosecond Pulse Generation and Modulation in Standard Digital CMOS  

E-print Network

A 10 GS/s Distributed Waveform Generator for Sub-Nanosecond Pulse Generation and Modulation, Email:hwu@ece.rochester.edu Abstract-- A distributed waveform generator is presented for sub-nanosecond pulse generation in UWB impulse radios. It time- interleaves multiple digital pulse generators, and uses

Wu, Hui

378

Ultra-wideband polarimetric imaging of corner reflectors in foliage  

Microsoft Academic Search

An ultrawideband imaging radar was developed. It is a highly mobile, ground-based system capable of 2D and 3D imaging at very close ranges to a synthetic aperture. The radar is fully coherent over two bandwidths (0.1 to 2 GHz and 2 to 18 GHz) and is being used for target and for foliage penetration measurements. The emphasis of the program

D. J. Blejer; S. M. Scarborough; C. E. Frost; H. R. Catalan; K. H. McCoin; J. Roman; D. M. Mukai

1992-01-01

379

Ultra wideband horn antenna for microwave imaging application  

Microsoft Academic Search

Recently, high-contrast and high-resolution microwave imaging has been extensively studied in the detection of early breast cancer, This method is based on the contrast in electrical properties of healthy fatty breast tissues and malignant tissues. In this paper we design a new TEM double-ridged horn antenna for microwave imaging application. Proposed antenna is simulated with two commercially available packages, namely

Hana Amjadi; Farzad Tavakkol Hamedani

2011-01-01

380

Non-inertial ultra-wideband acoustic transducers  

NASA Astrophysics Data System (ADS)

In introductory and even some advanced textbooks covering ultrasonic transducers including piezoelectric discs, the transducers used for excitation are normally introduced as electrically driven mechanical oscillators operated reversely for detection. A refined treatment based on original work from the early 60's of the last century demonstrates that even in this simple case, electromagnetic-mechanical coupling is restricted to interfaces with the volume of transducer discs operating in part as inertial mass, which can also be provided by suitable backing with improved results. Geometrical effects in combination with the oscillating masses lead to resonances of the transducers limiting the applications. Thin transducer discs or film transducers, which are in comparison to the oscillating masses in the generated or detected acoustic waves approximately mass free, can be operated such that inertial effects in the transducer are reduced respectively almost avoided. Even though such transducers are available on a commercial basis and are well introduced for the generation and detection of Lamb waves, the basic underlying principles are usually not highlighted. These effects are experimentally demonstrated and compared to expectations based on basic principles. Schemes suitable to overcome bandwidth restrictions given by geometrical effects are discussed and an application of wideband transducers for Lamb waves used for stress detection is exemplified.

Amjad, U.; Hahn, K.; Tang, T. G.; Grill, W.

2009-03-01

381

Ultra wideband antenna array processing under spatial aliasing  

E-print Network

gain of the proposed setup is potentially signiflcant, speciflcally when the transmitters are closely spaced and under low Signal to Noise Ratio (SNR), which makes it applicable to license-free communication. v To My parents, Nayereh and Kazem, my... . . . . . . . . . . . . . . . . . . . 34 V ERROR MAGNITUDES UNDER ALIASING : : : : : : : : : : 38 VI SIMULATION SETUP AND RESULTS : : : : : : : : : : : : : 45 A. MLE-based Simulation . . . . . . . . . . . . . . . . . . . . 45 viii CHAPTER Page B. Wideband Subspace-based Simulation...

Shapoury, Alireza

2009-05-15

382

Ultra-wideband printed circular monopole antenna array  

Microsoft Academic Search

In this paper, a printed monopole circular antenna array concept for use in the frequency 3.1 GHz - 10.6 GHz is presented. The design uses the printed monopole disc antenna in a four-element array to produce high gain and to shape the radiation pattern while maintaining good match of the frequency range of interest. The four printed disc monopole antennas

Zainul Ihsan; Klaus Solbach

2009-01-01

383

Recent Progress in Ultra-Wideband Microwave Breast Cancer Detection  

E-print Network

to find new methods for the early detection of breast cancer in order to provide treatment to patients screening methods include mammography, ultrasound techniques, and magnetic resonance imaging (MRI). Mammography is the most common method currently being clinically employed and promoted as a regular screening

Coates, Mark

384

Ultra-wideband and low-frequency SAR interferometry  

Microsoft Academic Search

The authors analyse different techniques for 3D SAR mapping. Interferometry using narrow-band SAR enables retrieval of topography but gives an ambiguous height. Stereoscopy can also be used but has degraded resolution due to speckle. For ultra-wide band SAR, i.e. wavelength-order resolution, these techniques converge and give similar vertical resolution. A significant advantage, however, is that the interferometric height becomes unambiguous

L. M. H. Ulander; P. O. Frolund

1996-01-01

385

Digitizing of UWB Signals Based on Frequency Channelization Won Namgoong, Lei Feng  

E-print Network

Digitizing of UWB Signals Based on Frequency Channelization Won Namgoong, Lei Feng Department receiver for digitizing UWB signals. 1 INTRODUCTION Although great headway has recently been made, therefore, the UWB signal needs to be digitized at the signal Nyquist rate of several gigahertz, so that all

Southern California, University of

386

47 CFR 15.519 - Technical requirements for hand held UWB systems.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 false Technical requirements for hand held UWB systems. 15.519 Section...15.519 Technical requirements for hand held UWB systems. (a) UWB devices...under the provisions of this section must be hand held, i.e., they are relatively...

2010-10-01

387

47 CFR 15.519 - Technical requirements for hand held UWB systems.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 false Technical requirements for hand held UWB systems. 15.519 Section...15.519 Technical requirements for hand held UWB systems. (a) UWB devices...under the provisions of this section must be hand held, i.e. , they are...

2012-10-01

388

47 CFR 15.519 - Technical requirements for hand held UWB systems.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 false Technical requirements for hand held UWB systems. 15.519 Section...15.519 Technical requirements for hand held UWB systems. (a) UWB devices...under the provisions of this section must be hand held, i.e. , they are...

2013-10-01

389

47 CFR 15.519 - Technical requirements for hand held UWB systems.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 false Technical requirements for hand held UWB systems. 15.519 Section...15.519 Technical requirements for hand held UWB systems. (a) UWB devices...under the provisions of this section must be hand held, i.e., they are relatively...

2011-10-01

390

pulses radiated per antenna, and the number of antennas in an array. For example, if each pulse carries 1 mJ of energy, it would  

E-print Network

ridged pyramidal horn antenna with curved launching plane for pulse radiation, IEEE Antennas Wirelesspulses radiated per antenna, and the number of antennas in an array. For example, if each pulse period. In a practical UWB microwave radar imaging scenario, an array of antennas surrounds the breast

Tsang, Leung

391

Generation of ultrawideband pulses using a distributed fiber-link system  

NASA Astrophysics Data System (ADS)

This work develops a simple distributed fiber-link system with a newly designed antenna to generate ultrawideband (UWB) pulses for indoor wireless communications. The proposed system comprises a gain-switched distributed feedback laser diode (DFB-LD), electro-absorption modulator (EAM), a photodetector and a pair of coplanar waveguide (CPW) antennas. This optical approach can tolerate pulse dispersion and prevent the generation of intersymbol interference (ISI), since the optical pulse width is easily adjustable, providing better radio communication, as determined by the generation of UWB signal. Furthermore, the simulated and experimental results demonstrate that the proposed system can generate high-quality UWB pulse signals for application to future indoor high-bit-rate wireless communications.

Lin, Wen-Piao; Li, Ruei Chi

2008-07-01

392

Joint localization of stationary and moving targets behind walls using sparse scene recovery  

NASA Astrophysics Data System (ADS)

We consider sparsity-driven joint localization of stationary and moving targets inside enclosed structures using a reduced set of spatial-fast time-slow time observations in ultra-wideband (UWB) pulsed radar platforms. We exploit the compact temporal support of the UWB signal to suppress the front wall clutter through time gating. The resulting enhancement in the signal-to-clutter ratio enables application of compressive sensing (CS) for scene reconstruction. We establish an appropriate signal model that permits formulation of linear modeling with sensing matrices so as to achieve efficient CS-based localization of stationary and moving targets in the downrange-crossrange-velocity space. We demonstrate the effectiveness of the proposed scheme using real data collected in a laboratory environment.

Qian, Jiang; Ahmad, Fauzia; Amin, Moeness G.

2013-04-01

393

A 500MS/s 5b ADC in 65nm CMOS Brian P. Ginsburg and Anantha P. Chandrakasan  

E-print Network

of the channels has a split capacitor array to reduce switching energy and sensitivity to digital timing skew. Keywords: UWB, ADC, SAR, CMOS, time-interleaved Introduction Ultra-wideband (UWB) radio is an emerging of increased variability. Two new techniques are incorporated to improve energy-efficiency. A split capacitor

Chandrakasan, Anantha

394

1818 IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS, VOL. 4, NO. 4, JULY 2005 A General Model and SINR Analysis of Low  

E-print Network

in the presence of narrowband interference, multipath and additive white Gaussian noise, for both matched- filter and SINR Analysis of Low Duty-Cycle UWB Access Through Multipath With Narrowband Interference and Rake coexisting narrowband services is a critical factor affecting performance of ultra-wideband (UWB) radio

Yang, Liuqing

395

Published in IET Communications Received on 25th January 2008  

E-print Network

.1049/iet-com:20080058 ISSN 1751-8628 Impacts of impulse-based ultra-wideband data links on cooperative, Department of Electrical and Electronic Engineering, Imperial College, London SW7 2BT, UK E-mail: s of such UWB data links, mainly the more likely adopted impulse-based UWB data links for low data rate

Leung, Kin K.

396

A 0.18 ?m CMOS low noise amplifier using a current reuse technique for 3.1-10.6 GHz UWB receivers  

NASA Astrophysics Data System (ADS)

A new, low complexity, ultra-wideband 3.1-10.6 GHz low noise amplifier (LNA), designed in a chartered 0.18 ?m RFCMOS technology, is presented. The ultra-wideband LNA consists of only two simple amplifiers with an inter-stage inductor connected. The first stage utilizing a resistive current reuse and dual inductive degeneration technique is used to attain a wideband input matching and low noise figure. A common source amplifier with an inductive peaking technique as the second stage achieves high flat gain and wide -3 dB bandwidth of the overall amplifier simultaneously. The implemented ultra-wideband LNA presents a maximum power gain of 15.6 dB, and a high reverse isolation of -45 dB, and good input/output return losses are better than -10 dB in the frequency range of 3.1-10.6 GHz. An excellent noise figure (NF) of 2.8-4.7 dB was obtained in the required band with a power dissipation of 14.1 mW under a supply voltage of 1.5 V An input-referred third-order intercept point (IIP3) is -7.1 dBm at 6 GHz. The chip area, including testing pads, is only 0.8 × 0.9 mm2.

Chunhua, Wang; Qiuzhen, Wan

2011-08-01

397

0.7-GHz-Bandwidth DS-UWB-IR System for Low-Power Wireless Communications  

NASA Astrophysics Data System (ADS)

A direct-sequence ultra-wideband impulse radio (DSUWB-IR) system is developed for low-power wireless applications such as wireless sensor networks. This system adopts impulse radio characterized by a low duty cycle, and a direct-sequence 0.7-GHz bandwidth, which enables low-power operation and extremely precise positioning. Simulation results reveal that the system achieves a 250-kbps data rate for 30-mdistance wireless communications using realistic specifications. We also conduct an experiment that confirms the feasibility of our system.

Fujiwara, Ryosuke; Maeki, Akira; Mizugaki, Kenichi; Ono, Goichi; Nakagawa, Tatsuo; Norimatsu, Takayasu; Kokubo, Masaru; Miyazaki, Masayuki; Okuma, Yasuyuki; Hayakawa, Miki; Kobayashi, Shinsuke; Koshizuka, Noboru; Sakamura, Ken

398

Bistability and hysteresis in the emergence of pulses in microstrip Gunn-diode circuits  

NASA Astrophysics Data System (ADS)

We develop time-domain simulations of microwave and THz radiation sources built as arrays of active devices when the radiation wavelength is small as compared to spacing between electronic components. We pursue an approach when the system is represented by equations with time-delay feedback that could generate chaos and other forms of complicated dynamics. The approach simplifies simulations of ultra-wideband effects and exceeds capabilities of frequency-domain methods. As a model case, we simulated a microstrip circuit with Gunn diode and a remote resonator emitting the radiation towards infinity. We observed the emergence of either the continuous waves or the trains of high-frequency pulses depending on the bias conditions. We found bistability and hysteresis in the onset of different oscillation modes that depends on the way of driving the bias voltage into the domain of instability of the given system. The results would allow one to improve the design of THz radiation sources with time-delay coupling between components.

Yurchenko, V. B.; Yurchenko, L. V.

2014-12-01

399

A low noise CMOS RF front-end for UWB 6-9 GHz applications  

NASA Astrophysics Data System (ADS)

An integrated fully differential ultra-wideband CMOS RF front-end for 6-9 GHz is presented. A resistive feedback low noise amplifier and a gain controllable IQ merged folded quadrature mixer are integrated as the RF front-end. The ESD protected chip is fabricated in a TSMC 0.13 ?m RF CMOS process and achieves a maximum voltage gain of 23-26 dB and a minimum voltage gain of 16-19 dB, an averaged total noise figure of 3.3-4.6 dB while operating in the high gain mode and an in-band IIP3 of -12.6 dBm while in the low gain mode. This RF front-end consumes 17 mA from a 1.2 V supply voltage.

Feng, Zhou; Ting, Gao; Fei, Lan; Wei, Li; Ning, Li; Junyan, Ren

2010-11-01

400

Experimental UWB channel characterisation of an electromagnetically small environment  

Microsoft Academic Search

This paper presents an experimental characterization of the ultra-wide bandwidth (UWB) indoor channel based on an extensive measurement in a PC tower case environment to identify the optimum channel performance. The investigation is based on the analysis of the statistical properties of the multipath profiles, measured over a finely spaced measurement grid. The small-scale statistics of the received path energy

J. Gelabert; A. Kavatjikidis; D. J. Edwards; C. J. Stevens

2009-01-01

401

Improved Equalization for UWB Multiband OFDM Sylvain Traverso  

E-print Network

Improved Equalization for UWB Multiband OFDM Sylvain Traverso Myriam Ariaudo Jean-Luc Gautier ECIME. The proposed equalizer is optimal in the least square sense, and does not increase complexity compared to classical equalizers. The performance of this equalizer is studied for chan- nel delay spread below

Paris-Sud XI, Université de

402

Through-wall UWB radar operating within FCC's mask for sensing heart beat and breathing rate  

Microsoft Academic Search

Non-invasive sensing of heart beat and breathing rate using UWB radar within the FCC's mask between 3.1 to 10.6 GHz and operating within -41 dbm\\/MHz has been developed. Compared to existing radars, the EIRP of UWB is much lower and it can also achieve comparable performance with the unique capability of through the wall environment. The UWB radar transceiver system

M. Y. W. Chia; S. W. Leong; C. K. Sim; K. M. Chan

2005-01-01

403

Impacts of Narrowband Interference on OFDM-UWB Receivers: Analysis and Mitigation  

Microsoft Academic Search

Orthogonal frequency-division multiplexing (OFDM)-based ultra-wide-band (UWB) transceivers hold the promise to revolutionize the next generation of short-range wireless networks and to be adopted in electronics products for both civil and military applications. For the UWB transceivers to coexist with nearby devices, it is necessary to design efficient UWB receivers whose operation is robust to narrowband interferences (NBI). This paper conducts

Kai Shi; Yi Zhou; Burak Kelleci; Timothy Wayne Fischer; Erchin Serpedin; Aydn lker Karsilayan

2007-01-01

404

Performance of UWB Impulse Radio With Planar Monopoles Over On-Human-Body Propagation Channel for Wireless Body Area Networks  

Microsoft Academic Search

Ultrawideband (UWB) is a promising technology for wireless body area networks (WBANs). This paper studied the impacts of 3.1-10.6 GHz on-human-body UWB channel on the impulse radio WBAN system. A performance evaluation method is presented for the realistic UWB WBAN systems, which observes the waveform distortion along the signal path. The measurement and characterization of the 3.1-10.6 GHz on-human-body UWB

Yue Ping Zhang; Qiang Li

2007-01-01

405

A Compact Polyimide-Based UWB Antenna for Flexible Electronics  

Microsoft Academic Search

In this letter, we present a compact ultrawideband (UWB) antenna printed on a 50.8-$ \\\\mu$m Kapton polyimide substrate. The antenna is fed by a linearly tapered coplanar waveguide (CPW) that provides smooth transitional impedance for improved matching. The proposed design is tuned to cover the 2.2–14.3-GHz frequency range that encompasses both the 2.45-GHz Industrial, Scientific, Medical (ISM) band and the

Haider R. Khaleel; Hussain M. Al-Rizzo; Daniel G. Rucker; Seshadri Mohan

2012-01-01

406

Rake Receiver Improvement for Residual Interference Cancellation in UWB Context  

Microsoft Academic Search

In the context of PAM Time-Hopping\\/Direct Se- quence Impulse Radio Ultra Wide Band (IR-UWB), a residual interference occurs at the output of the Rake Receiver when realistic multipath propagation channel is considered even if a large guard-time interval is used. As a consequence, the performance is limited and exhibits BER floor. In this paper, we explicitally explains what causes such

Anne-laure Deleuze; Christophe Le Martret; Philippe Ciblat

2007-01-01

407

Novel method of UWB antenna optimization for specified input signal forms by means of genetic algorithm  

Microsoft Academic Search

A novel optimization procedure for the design of antennas for ultrawideband (UWB) wireless communication systems is presented. The optimization is based on the time-domain characteristics of the antenna. The optimization procedure was applied to a simplified version of the volcano smoke antenna proposed by Kraus. However, any other type of UWB antenna can be treated with the same technique. Our

Nikolay Telzhensky; Yehuda Leviatan

2006-01-01

408

Robust BPSK impulse radio UWB-over-fiber systems using optical phase modulation  

Microsoft Academic Search

The impact of fiber dispersion on the performance of optical phase modulated impulse- radio-ultrawideband (IR-UWB) signals is experimentally investigated. 2Gbps BPSK IR-UWB over 78km fiber transmission is successfully achieved by using digital coherent detection. ©2011 Optical Society of America OCIS codes: (060.1660) Coherent communications, (060.5625) Radio frequency photonics.

Tien-Thang Pham; Neil Guerrero Gonzalez; Xianbin Yu; Darko Zibar; Lars Dittmann; Idelfonso Tafur Monroy

2011-01-01

409

Ultra wide band (UWB) systems and their implications to electromagnetic environment  

Microsoft Academic Search

Ultra Wide Band (UWB) systems have received considerable interest in recent years as a system that might offer technical improvements in conventional electronic systems. Defence applications of UWB signals include communication radar, electronic intelligence and electronic warfare. Defence radio and radar systems will require signals free from interception exploitation and interference. The electronic warfare sequence of measures, countermeasures, counter-countermeasures leads

D. C. Pande

1999-01-01

410

Compact Cactus-Shaped Ultra Wide-Band (UWB) Monopole on Organic Symeon Nikolaou*(1)  

E-print Network

Compact Cactus-Shaped Ultra Wide-Band (UWB) Monopole on Organic Substrate Symeon Nikolaou*(1, U.S.A. simos@ece.gatech.edu Abstract: The implementation of a novel cactus-shaped monopole antenna-segments broadband antennas proposed in [4-5] do not cover the whole UWB range. In this paper, a compact cactus

Tentzeris, Manos

411

Sense-Through-Wall Human Detection Using UWB Radar With Sparse SVD  

E-print Network

-Through-Wall Human Detection Using UWB Radar With Sparse SVD Xiaoyang Lia , Qilian Liangb , Francis C.M. Laua, Singular Value Decomposition, Lanczos Process 1. Introduction UWB radars are used nowadays for different the highest and lowest frequencies of interest and con- tains about 95% of the signal power [2][3]. Such radar

Lau, Francis C.M.

412

BLIND SYNCHRONIZATION IN ASYNCHRONOUS UWB NETWORKS BASED ON THE TRANSMIT-REFERENCE SCHEME  

E-print Network

- nel with a long impulse response. The proposed al- gorithm processes a block of received data samples, takes advantage of a shift invariance structure in the frequency domain, and applies a MUSIC-like search UWB network. The design of UWB systems based on impulse radio is complicated by the fact

van der Veen, Alle-Jan

413

Distortion effects in a switch array UWB radar for time-lapse imaging of human heartbeats  

NASA Astrophysics Data System (ADS)

Cardiovascular diseases (CVD) are a major cause of deaths all over the world. Microwave radar can be an alternative sensor for heart diagnostics and monitoring in modern healthcare that aids early detection of CVD symptoms. In this paper measurements from a switch array radar system are presented. This UWB system operates below 3 GHz and does time-lapse imaging of the beating heart inside the human body. The array consists of eight fat dipole elements. With a switch system, every possible sequence of transmit/receive element pairs can be selected to build a radar image from the recordings. To make the radar waves penetrate the human tissue, the antenna array is placed in contact with the body. Removal of the direct signal leakage through the antennas and body surface are done by high-pass (HP) filtering of the data prior to image processing. To analyze the results, measurements of moving spheres in air and simulations are carried out. We see that removal of the direct signal introduces amplitude distortion in the images. In addition, the effect of small target motion between the collection times of data from the individual elements is analyzed. With low pulse repetition frequency (PRF) this motion will distort the image. By using data from real measurements of heart motion in simulations, we analyze how the PRF and the antenna geometry influence this distortions.

Brovoll, Sverre; Berger, Tor; Aardal, Åyvind; Lande, Tor S.; Hamran, Svein-Erik

2014-05-01

414

Design and analysis of a UWB low-noise amplifier in the 0.18 ?m CMOS process  

NASA Astrophysics Data System (ADS)

An ultra-wideband (3.1-10.6 GHz) low-noise amplifier using the 0.18 ?m CMOS process is presented. It employs a wideband filter for impedance matching. The current-reused technique is adopted to lower the power consumption. The noise contributions of the second-order and third-order Chebyshev filers for input matching are analyzed and compared in detail. The measured power gain is 12.4-14.5 dB within the bandwidth. NF ranged from 4.2 to 5.4 dB in 3.1-10.6 GHz. Good input matching is achieved over the entire bandwidth. The test chip consumes 9 mW (without output buffer for measurement) with a 1.8 V power supply and occupies 0.88 mm2.

Yi, Yang; Zhuo, Gao; Liqiong, Yang; Lingyi, Huang; Weiwu, Hu

2009-01-01

415

Capacity of UWB wireless channel for neural recording systems.  

PubMed

Ultra wide-band (UWB) short-range communication systems are valuable in medical technology, particularly for implanted devices, due to their low-power consumption, low cost, small size and high data rates. Monitoring of neural responses in the brain requires high data rate if we target a system supporting a large number of sensors. In this work, we are interested in the evaluation of the capacity of the ultra wide-band (UWB) channel that we could exploit using a realistic model of the biological channel. The channel characteristics are examined under two scenarios that are related to TX antenna placements. Using optimal power spectrum allocation (OPSA) at the transmitter side, we have computed this capacity by taking into account the fading characteristics of the channel. The results show the pertinence of the optimal power spectrum allocation for this type of channel. An improvement by a factor of 2 to 3 over a uniform power spectrum allocation (UPSA) when the SNR <; 0 dB was obtained. When the SNR is > 40 dB, both approaches give similar results. Antennas placement is examined under two scenarios having contrasting power constraints. PMID:25570860

El Khaled, Mohamad; Bahrami, Hadi; Fortier, Paul; Gosselin, Benoit; Rusch, Leslie Ann

2014-08-01

416

Numerical and experimental investigation of an ultrawideband ridged pyramidal horn antenna with curved launching plane for pulse radiation  

Microsoft Academic Search

We report the numerical analysis and experimental characterization of an ultrawideband (UWB) antenna designed for radiating short microwave pulses. The antenna consists of a pyramidal horn, a ridge, and a curved launching plane terminated with resistors. The pyramidal horn is connected to the outer conductor of the coaxial feed and serves as the ground plane. The curved launching plane is

Xu Li; Susan C. Hagness; Min K. Choi; Daniel W. van der Weide

2003-01-01

417

Through-wall imaging and characterization of human activity using ultrawideband (UWB) random noise radar  

NASA Astrophysics Data System (ADS)

Recent terrorist activities and law-enforcement situations involving hostage situations underscore the need for effective through-wall imaging. Current building interior imaging systems are based on short-pulse waveforms, which require specially designed antennas to subdue unwanted ringing. In addition, periodically transmitted pulses of energy are easily recognizable by the intelligent adversary who may employ appropriate countermeasures to confound detection. A coherent polarimetric random noise radar architecture is being developed based on UWB technology and software defined radio, which has great promise in its ability to covertly image obscured targets. The main advantages of the random noise radar lie in two aspects: first, random noise waveform has an ideal "thumbtack" ambiguity function, i.e., its down range and cross range resolution can be separately controlled, thus providing unambiguous high resolution imaging at any distance; second, random noise waveform is inherently low probability of intercept (LPI) and low probability of detection (LPD), i.e., it is immune from detection, jamming, and interference. Thus, it is an ideal candidate sensor for covert imaging of obscured regions in hostile environments. The coherency in the system can be exploited to field a fully-polarimetric system that can take advantage of polarization features in target recognition. Moving personnel can also be detected using Doppler processing. Simulation studies are used to analyze backscattered signals from the walls, and humans and other targets behind the walls. Real-time data processing shows human activity behind the wall and human target tracking. The high resolution provides excellent multipath and clutter rejection.

Lai, Chieh-Ping; Narayanan, Ram M.

2005-05-01

418

A 16.3 pJ/pulse low-complexity and energy-efficient transmitter with adjustable pulse parameters  

NASA Astrophysics Data System (ADS)

This paper presents a novel, fully integrated transmitter for 3-5 GHz pulsed UWB. The BPSK modulation transmitter has been implemented in SMIC CMOS 0.13 ?m technology with a 1.2-V supply voltage and a die size of 0.8 × 0.95 mm2. This transmitter is based on the impulse response filter method, which uses a tunable R paralleled with a LC frequency selection network to realize continuously adjustable pulse parameters, including bandwidth, width and amplitude. Due to the extremely low duty of the pulsed UWB, a proposed output buffer is employed to save power consumption significantly. Finally, measurement results show that the transmitter consumes only 16.3 pJ/pulse to achieve a pulse repetition rate of 100 Mb/s. Generated pulses strictly comply with the FCC spectral mask. The continuously variable pulse width is from 900 to 1.5 ns and the amplitude with the minimum 178 mVpp and the maximum 432 mVpp can be achieved.

Jun, Jiang; Yi, Zhao; Ke, Shao; Hu, Chen; Lingli, Xia; Zhiliang, Hong

2011-06-01

419

A 3.1-4.8 GHz CMOS receiver for MB-OFDM UWB  

NASA Astrophysics Data System (ADS)

An integrated fully differential ultra-wideband CMOS receiver for 3.1-4.8 GHz MB-OFDM systems is presented. A gain controllable low noise amplifier and a merged quadrature mixer are integrated as the RF front-end. Five order Gm-C type low pass filters and VGAs are also integrated for both I and Q IF paths in the receiver. The ESD protected chip is fabricated in a Jazz 0.18 ?m RF CMOS process and achieves a maximum total voltage gain of 65 dB, an AGC range of 45 dB with about 6 dB/step, an averaged total noise figure of 6.4 to 8.8 dB over 3 bands and an in-band IIP3 of -5.1 dBm. The receiver occupies 2.3 mm2 and consumes 110 mA from a 1.8 V supply including test buffers and a digital module.

Guang, Yang; Wang, Yao; Jiangwei, Yin; Renliang, Zheng; Wei, Li; Ning, Li; Junyan, Ren

2009-01-01

420

TIME-BASED ARITHMETIC USING STEP FUNCTIONS Vishnu Ravinuthula and John G. Harris  

E-print Network

of such techniques as class D amplifiers, spike-based sensors and even ultra-wideband (UWB) signal transmis- sion and I2 are connected to the source of PMOS transistors charge the capacitor C depending on the timing of the step inputs. A comparator senses the voltage across the capacitor and outputs a step when the voltage

Harris, John G.

421

202 2006 IEEE International Solid-State Circuits Conference ISSCC 2006 / SESSION 11 / RF BUILDING BLOCKS AND PLLS / 11.6  

E-print Network

and Telecommunications Research Institute, Daejon, Korea Ultra wideband (UWB) radio communication is capable of a high.6.2. This circuit includes the shunt capacitor C1, which is also known as the Miller capacitor, and a shunt inductor. It is also important to note that an addi- tional capacitor C2 is present in series with the input. The over

Ha, Dong S.

422

Bandwidth dependence of CW ranging to UHF RFID tags in severe multipath environments  

Microsoft Academic Search

In this paper the impact of the signal bandwidth on the performance of frequency modulated continuous wave (FMCW) radar based ranging to ultra high frequency (UHF) radio frequency identification (RFID) tags is investigated. The analyses are based on ultra-wideband (UWB) channel measurements performed in a warehouse portal, which is a severe multipath environment. It is illustrated that the available bandwidth

Gang Li; Daniel Arnitz; Randolf Ebelt; Ulrich Muehlmann; Klaus Witrisal; Martin Vossiek

2011-01-01

423

Information Raining for Mobile Hotspots in 4G Wireless Networks  

E-print Network

Cellular Optical WLAN Fast Ethernet 100 Information Raining Fig. 1. Mobility versus bandwidth plot cellular systems have not been designed to support the speeds beyond 250 km/h. The second challenge arises), ultra wideband (UWB), etc, it is possible to achieve bit rates in the order of 100 Mbit/s for fast

Valaee, Shahrokh

424

Challenge: Ultra-Low-Power Energy-Harvesting Active Networked Tags (EnHANTs)  

E-print Network

, ultra-wideband (UWB) circuit design, and organic electronic harvesting techniques will enable ranges. Moreover, solar energy harvesting based on organic semiconductors allows having flexible solarChallenge: Ultra-Low-Power Energy-Harvesting Active Networked Tags (EnHANTs) Maria Gorlatova, Peter

Zussman, Gil

425

Tennessee Tech Time-Reversal Based Range Extension Technique for  

E-print Network

I I Tennessee Tech UNIVERSITY Time-Reversal Based Range Extension Technique for Ultra-wideband (UWB for Manufacturing Research Tennessee Technological University Cookeville, TN 38501 * 20070924084 I #12;REPORT ORGANIZATION NAME(S) AND ADDRESS(ES) 8. PERFORMING ORGANIZATION Tennessee Technological University REPORT

Qiu, Robert Caiming

426

Evaluation of an ultra-wide-band propagation channel  

Microsoft Academic Search

This paper describes the results of an ultra-wideband (UWB) propagation study in which arrays of propagation measurements were made. After a description of the propagation measurement technique, an approach to the spatial and temporal decomposition of an array of measurements into wavefronts impinging on the receiving array is presented. Based on a modification of the CLEAN algorithm, this approach provides

R. Jean-Marc Cramer; Robert A. Scholtz; Moe Z. Win

2002-01-01

427

1930 IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS, VOL. 5, NO. 7, JULY 2006 Low-Complexity Blind Synchronization and  

E-print Network

communication systems: from classical narrowband and emerging (ultra) wideband (UWB) point-to-point links- nications. In narrowband (NB) transmissions over additive white Gaussian noise (AWGN) channels, timing acquisition amounts to peak-picking the correlation of the transmit-filter with its template formed

Giannakis, Georgios

428

The diamond dipole: a Gaussian impulse antenna  

Microsoft Academic Search

When a typical narrowband antenna is excited by an ultra-wideband (UWB) impulse, the antenna rings at its resonant frequency, stretching out the waveform in time. A resonant antenna, like the bow tie, discone, or bicone have been available for years. A bow tie has a relatively high input impedance, and requires a matching balun to make it useable with a

H. G. Schantz; L. Fullerton

2001-01-01

429

A novel impulse radio network for tactical military wireless communications  

Microsoft Academic Search

Two of the major concerns in tactical military wireless communication networks are covertness and throughput. Impulse radio is an ultra-wideband code division multiple access (UWB-CDMA) technique being considered as the physical layer for future networks. Impulse radio exhibits low power spectral density and relatively high immunity to fading but suffers from relatively long acquisition times. In traditional packet radio networks

Santosh S. Kolenchery; J. K. Townsend; J. A. Freebersyser

1998-01-01

430

A comparative study of algorithms for radar imaging from gapped data  

Microsoft Academic Search

In ultra wideband (UWB) radar imagery, there are often cases where the radar's operating bandwidth is interrupted due to various reasons, either periodically or randomly. Such interruption produces phase history data gaps, which in turn result in artifacts in the image if conventional image reconstruction techniques are used. The higher level artifacts severely degrade the radar images. In this work,

Xiaojian Xu; Ruixue Luan; Li Jia; Ying Huang

2007-01-01

431

EM Channel Estimation in a Low-cost UWB Receiver based on Energy Detection  

E-print Network

greater than 100Mb/s with a simple impulse radio UWB receiver. I. INTRODUCTION The future of ultra, the energy detector (ED) based on a simple schottky diode and a capacitor is by far the less complex

Boyer, Edmond

432

Non-Coherent UWB Communication in the Presence of Multiple Narrowband Interferers  

E-print Network

There has been an emerging interest in non-coherent ultra-wide bandwidth (UWB) communications, particularly for low-data rate applications because of its low-complexity and low-power consumption. However, the presence of ...

Rabbachin, Alberto

433

Using UWB Radios as Sensors for Disaster Jeongeun Julie Lee and Suresh Singh  

E-print Network

Using UWB Radios as Sensors for Disaster Recovery Jeongeun Julie Lee and Suresh Singh Department Reconstruction of wall based on signal attenuation and relative position information Sensor knows approximate

Singh, Suresh

434

VCSEL-based gigabit IR-UWB link for converged communication and sensing applications in optical metro-access networks  

NASA Astrophysics Data System (ADS)

We report on experimental demonstration of an impulse radio ultrawideband (IR-UWB) based converged communication and sensing system. A 1550-nm VCSEL-generated IR-UWB signal is used for 2-Gbps wireless data distribution over 800-m and 50-km single mode fiber links which present short-range in-building and long-reach access network applications. The IR-UWB signal is also used to simultaneously measure the rotational speed of a blade spinning between 18 and 30 Hz. To the best of our knowledge, this is the very first demonstration of a simultaneous gigabit UWB telecommunication and wireless UWB sensing application, paving the way forward for the development and deployment of converged UWB VCSEL-based technologies in access and in-building networks of the future.

Pham, Tien-Thang; Braidwood Gibbon, Timothy; Tafur Monroy, Idelfonso

2012-11-01

435

Space-Time-Frequency Code implementation in MB-OFDM UWB communications: Design criteria and performance  

Microsoft Academic Search

This paper proposes a general framework of space-time-frequency codes (STFCs) for multi-band orthogonal frequency division multiplexing (MB-OFDM) ultra-wide band (UWB) communications systems. A great similarity between the STFC MB-OFDM UWB systems and conventional wireless complex orthogonal space-time block code (CO STBC) multiple-input multiple-output (MIMO) systems is discovered. This allows us to quantify the pairwise error probability (PEP) of the proposed

Le Chung Tran; Alfred Mertins

2009-01-01

436

Design and Evaluation of a Compact Antenna for Implant-to-Air UWB Communication  

Microsoft Academic Search

A compact, printed, capsule-shaped ultrawideband (UWB) antenna for biomedical implants is presented. The 10-dB return loss bandwidth of the proposed antenna is 3.5-4.5 GHz, which covers the recently proposed UWB for biomedical applications. The antenna matching has been optimized using CST Microwave Studio and verified by measurements. An optimized feed mechanism to reduce guided wavelength, as well as integration with

Tharaka Dissanayake; Mehmet R. Yuce; Chee Ho

2009-01-01

437

Double-sided printed bow-tie antenna for UWB communications  

Microsoft Academic Search

This letter proposes a double-sided printed bow-tie antenna for ultra wide band (UWB) applications. The frequency band considered is 3.1-10.6 GHz, which has been approved by the Federal Communications Commission as a commercial UWB band. The proposed antenna has a return loss less than 10 dB, phase linearity, and gain flatness over the above frequency band.

Katsuki Kiminami; Akimasa Hirata; Toshiyuki Shiozawa

2004-01-01

438

UWB Antennas and MIMO Antenna Arrays Development for Near-Field Imaging  

Microsoft Academic Search

UWB radar is the most promising radar system for the future. In addition, by combining the UWB and array signal processing, one can obtain 3-D images of the objects for classification and identification, which is very useful in many applications. To achieve high-resolution real-time 3-D imaging radar, two essential items are missing in the current technology: dedicated antenna systems for

Y. Yang

2011-01-01

439

A novel direction of arrival estimation technique using a single UWB antenna  

Microsoft Academic Search

In this paper, we propose a novel DOA estimation technique for broadband signals using a single UWB antenna inspired by the human auditory system. The received spectra of the UWB antenna are incident angle dependent in the x-y, x-z and y-z planes. The estimated DOA is then obtained by evaluating the correlation coefficients of the measured spectra with pre-determined incident

Rongguo Zhou; Hao Xin

2010-01-01

440

The Design of UWB Bandpass Filter-Combined Ultra-Wide Band Antenna  

Microsoft Academic Search

We have proposed a compact filter-combined ultra-wide band antenna for the use of DS-UWB low band or MB-OFDM lower three bands (3.1-5.2 GHz). The designed antenna has a microstrip-fed trapezoidal radiating patch, UWB band pass filter using the dumbbell-shaped DGS (defected ground structure) and IDC (interdigital capacitor), two steps for impedance matching, and microstrip feeding. Three kinds of prototypes (trapezoidal

Jung N. Lee; Jin H. Yoo; Ji H. Kim; Jong K. Park; Jin S. Kim

2008-01-01

441

Non-Coherent UWB Communication in the Presence of Multiple Narrowband Interferers  

Microsoft Academic Search

There has been an emerging interest in non-coherent ultra-wide bandwidth (UWB) communications, particularly for low-data rate applications because of its low-complexity and low-power consumption. However, the presence of narrowband (NB) interference severely degrades the communication performance since the energy of the interfering signals is also collected by the receiver. In this paper, we compare the performance of two non-coherent UWB

Alberto Rabbachin; Tony Q. S. Quek; Pedro C. Pinto; Ian Oppermann; Moe Z. Win

2010-01-01

442

Service multicasting by all-optical routing of 1 Gb\\/s IR-UWB for in-building networks  

Microsoft Academic Search

We propose and demonstrate, for the first time, service multicasting by all-optical routing of 1 Gb\\/s IR-UWB using XGM of SOA. This technique has potential applications for integrating IR-UWB with WDM PON and in-building networks. ©2011 Optical Society of America OCIS codes: (060.4510) Optical communications; (060.5625) Radio frequency photonics.

S. T. Abraha; N. C. Tran; C. M. Okonkwo; H. S. Chen; E. Tangdiongga; A. M. J. Koonen

2011-01-01

443

Three-dimensional FDTD simulation of biomaterial exposure to electromagnetic nanopulses  

NASA Astrophysics Data System (ADS)

Ultra-wideband (UWB) electromagnetic pulses of nanosecond duration, or nanopulses, have recently been approved by the Federal Communications Commission for a number of different applications. They are also being explored for applications in biotechnology and medicine. The simulation of the propagation of a nanopulse through biological matter, previously performed using a two-dimensional finite-difference time-domain (FDTD) method, has been extended here into a full three-dimensional computation. To account for the UWB frequency range, the geometrical resolution of the exposed sample was 0.25 mm and the dielectric properties of biological matter were accurately described in terms of the Debye model. The results obtained from the three-dimensional computation support the previously obtained results: the electromagnetic field inside a biological tissue depends on the incident pulse rise time and width, with increased importance of the rise time as the conductivity increases; no thermal effects are possible for the low pulse repetition rates, supported by recent experiments. New results show that the dielectric sample exposed to nanopulses behaves as a dielectric resonator. For a sample in a cuvette, we obtained the dominant resonant frequency and the Q-factor of the resonator.

Simicevic, Neven

2005-11-01

444

Modeling, Real-Time Estimation, and Identification of UWB Indoor Wireless Channels  

SciTech Connect

In this paper, stochastic differential equations (SDEs) are used to model ultrawideband (UWB) indoor wireless channels. We show that the impulse responses for time-varying indoor wireless channels can be approximated in a mean square sense as close as desired by impulse responses that can be realized by SDEs. The state variables represent the inphase and quadrature components of the UWB channel. The expected maximization and extended Kalman filter are employed to recursively identify and estimate the channel parameters and states, respectively, from online received signal strength measured data. Both resolvable and non-resolvable multipath received signals are considered and represented as small-scaled Nakagami fading. The proposed models together with the estimation algorithm are tested using UWB indoor measurement data demonstrating the method s viability and the results are presented.

Olama, Mohammed M [ORNL] [ORNL; Djouadi, Seddik M [ORNL] [ORNL; Li, Yanyan [ORNL] [ORNL; Fathy, Aly [University of Tennessee (UT)] [University of Tennessee (UT)

2013-01-01

445

Wearable system-on-a-chip UWB radar for contact-less cardiopulmonary monitoring: present status.  

PubMed

The present status of the project aimed at the realization of an innovative wearable system-on-chip UWB radar for the cardiopulmonary monitoring is presented. The overall system consists of a wearable wireless interface including a fully integrated UWB radar for the detection of the heart beat and breath rates, and a IEEE 802.15.4 ZigBee low-power radio interface. The principle of operation of the UWB radar for the monitoring of the heart wall is summarized. With respect to the prior art, this paper reports the results of the experimental characterization of the intra-body channel loss, which has been carried out successfully in order to validate the theoretical model employed for the radar system analysis. Moreover, the main building blocks of the radar have been manufactured in 90 nm CMOS technology by ST-Microelectronics and the relevant performance are resulted in excellent agreement with those expected by post-layout simulations. PMID:19163907

Zito, D; Pepe, D; Mincica, M; Zito, F; De Rossi, D; Lanata, A; Scilingo, E P; Tognetti, A

2008-01-01

446

Smart container UWB sensor system for situational awareness of intrusion alarms  

DOEpatents

An in-container monitoring sensor system is based on an UWB radar intrusion detector positioned in a container and having a range gate set to the farthest wall of the container from the detector. Multipath reflections within the container make every point on or in the container appear to be at the range gate, allowing intrusion detection anywhere in the container. The system also includes other sensors to provide false alarm discrimination, and may include other sensors to monitor other parameters, e.g. radiation. The sensor system also includes a control subsystem for controlling system operation. Communications and information extraction capability may also be included. A method of detecting intrusion into a container uses UWB radar, and may also include false alarm discrimination. A secure container has an UWB based monitoring system

Romero, Carlos E.; Haugen, Peter C.; Zumstein, James M.; Leach, Jr., Richard R.; Vigars, Mark L.

2013-06-11

447

Ultrawide band sensor for rangefinding and communication  

NASA Astrophysics Data System (ADS)

Ultra-wideband (UWB) communications is a new field of technology that has a wide range of applications from range finding to wide bandwidth communications. Ultra-wideband signals are unusual because their bandwidth to center frequency ratio is not small and can be greater than 100%. Recent developments of integrating this technology on a chip have made it versatile and low cost. A number of areas especially those in ITS can benefit by this technology including Automatic Vehicle Identification (AVI), Advanced Traveler Information Systems (ATIS), Advanced Traffic Management Systems (ATMS), Transportation Planning, Collision Avoidance, and Automated Highway Systems (AHS). This paper describes the basics of UWB technology, describes its features, provides background on the technology, and provides some possible applications of UWB to ITS. This paper is not intended to be overly detailed in any one area, but, to provide information about a technology to a wide audience.

James, Robert D.; Mendola, Jeffrey B.

1995-12-01

448

Integrated Navigation Fusion Strategy of INS/UWB for Indoor Carrier Attitude Angle and Position Synchronous Tracking  

PubMed Central

In some GPS failure conditions, positioning for mobile target is difficult. This paper proposed a new method based on INS/UWB for attitude angle and position synchronous tracking of indoor carrier. Firstly, error model of INS/UWB integrated system is built, including error equation of INS and UWB. And combined filtering model of INS/UWB is researched. Simulation results show that the two subsystems are complementary. Secondly, integrated navigation data fusion strategy of INS/UWB based on Kalman filtering theory is proposed. Simulation results show that FAKF method is better than the conventional Kalman filtering. Finally, an indoor experiment platform is established to verify the integrated navigation theory of INS/UWB, which is geared to the needs of coal mine working environment. Static and dynamic positioning results show that the INS/UWB integrated navigation system is stable and real-time, positioning precision meets the requirements of working condition and is better than any independent subsystem. PMID:25121111

Wu, Yaheng; Hui, Jing; Wu, Lei; Zhou, Lijuan

2014-01-01

449

Integrated navigation fusion strategy of INS/UWB for indoor carrier attitude angle and position synchronous tracking.  

PubMed

In some GPS failure conditions, positioning for mobile target is difficult. This paper proposed a new method based on INS/UWB for attitude angle and position synchronous tracking of indoor carrier. Firstly, error model of INS/UWB integrated system is built, including error equation of INS and UWB. And combined filtering model of INS/UWB is researched. Simulation results show that the two subsystems are complementary. Secondly, integrated navigation data fusion strategy of INS/UWB based on Kalman filtering theory is proposed. Simulation results show that FAKF method is better than the conventional Kalman filtering. Finally, an indoor experiment platform is established to verify the integrated navigation theory of INS/UWB, which is geared to the needs of coal mine working environment. Static and dynamic positioning results show that the INS/UWB integrated navigation system is stable and real-time, positioning precision meets the requirements of working condition and is better than any independent subsystem. PMID:25121111

Fan, Qigao; Wu, Yaheng; Hui, Jing; Wu, Lei; Yu, Zhenzhong; Zhou, Lijuan

2014-01-01

450

Design of Pulse Waveform for Waveform Division Multiple Access UWB Wireless Communication System  

PubMed Central

A new multiple access scheme, Waveform Division Multiple Access (WDMA) based on the orthogonal wavelet function, is presented. After studying the correlation properties of different categories of single wavelet functions, the one with the best correlation property will be chosen as the foundation for combined waveform. In the communication system, each user is assigned to different combined orthogonal waveform. Demonstrated by simulation, combined waveform is more suitable than single wavelet function to be a communication medium in WDMA system. Due to the excellent orthogonality, the bit error rate (BER) of multiuser with combined waveforms is so close to that of single user in a synchronous system. That is to say, the multiple access interference (MAI) is almost eliminated. Furthermore, even in an asynchronous system without multiuser detection after matched filters, the result is still pretty ideal and satisfactory by using the third combination mode that will be mentioned in the study. PMID:24672294

Yin, Zhendong; Wang, Zhirui; Liu, Xiaohui

2014-01-01

451

Design of pulse waveform for waveform division multiple access UWB wireless communication system.  

PubMed

A new multiple access scheme, Waveform Division Multiple Access (WDMA) based on the orthogonal wavelet function, is presented. After studying the correlation properties of different categories of single wavelet functions, the one with the best correlation property will be chosen as the foundation for combined waveform. In the communication system, each user is assigned to different combined orthogonal waveform. Demonstrated by simulation, combined waveform is more suitable than single wavelet function to be a communication medium in WDMA system. Due to the excellent orthogonality, the bit error rate (BER) of multiuser with combined waveforms is so close to that of single user in a synchronous system. That is to say, the multiple access interference (MAI) is almost eliminated. Furthermore, even in an asynchronous system without multiuser detection after matched filters, the result is still pretty ideal and satisfactory by using the third combination mode that will be mentioned in the study. PMID:24672294

Yin, Zhendong; Wang, Zhirui; Liu, Xiaohui; Wu, Zhilu

2014-01-01

452

TOA Estimation Using UWB with Low Sampling Rate and Clock Drift Calibration  

E-print Network

. We adopt low-rate stroboscopic sampling, which can achieve an equivalent sampling rate as high for the stroboscopic sampling IR-UWB system, since a long preamble is required to collect sufficient data samples calibration significantly reduces the TOA estimation errors due to the drift, and that stroboscopic sampling

Leus, Geert

453

Time-of-arrival estimation by UWB radios with low sampling rate and clock drift calibration$  

E-print Network

-of-arrival Clock drift Stroboscopic sampling a b s t r a c t In this paper, we propose a time-of-arrival (TOA and is robust against clock drift. Low-rate stroboscopic sampling, which can achieve an equivalent sampling rate error sources in TOA estimation with stroboscopic sampling IR-UWB systems. Taking the drift into account

Leus, Geert

454

64-Channel UWB Wireless Neural Vector Analyzer and Phase Synchrony-Triggered Stimulator SoC  

E-print Network

the magnitude, but also the phase of neural signals. It is also the first SoC to demonstrate real-time on64-Channel UWB Wireless Neural Vector Analyzer and Phase Synchrony-Triggered Stimulator SoC Karim, phase and phase synchronization of neural signals. Abnormal phase synchrony triggers programmable

Genov, Roman

455

Design and implementation of frequency synthesizers for 3-10 ghz mulitband ofdm uwb communication  

E-print Network

. This work proposes a frequency band plan for multiband OFDM based UWB radios in the 3.1-10.6 GHz range. Based on this frequency plan, two 11-band frequency synthesizers are designed, implemented and tested making them one of the first frequency synthesizers...

Mishra, Chinmaya

2009-05-15

456

Dual polarized UWB antenna for free-space characterization of dielectric objects  

Microsoft Academic Search

This paper presents a dual polarized antenna for UWB sensor applications. The antenna consists of four circular radiating elements forming two dipoles excited in even mode in both polarizations. The geometry avoids directly crossed baluns but requires two power dividers and four tapered baluns because of four feeding points. It provides an input return loss better than 7dB over a

H. Mextorf; R. Martens; F. Daschner; R. Kno?chel

2010-01-01

457

Reconfigurable UWB printed monopole antenna with band rejection covering IEEE 802.11a\\/h  

Microsoft Academic Search

Reconfigurable microstrip UWB printed monopole antenna has been designed, analyzed, fabricated and measured with WLAN\\/Hyperlan2 band rejection characteristic. Band notch is realized by adding a parasitic patch in the back plan then it is cut into two parts which are connected by mean of two RF switches. The ON and OFF state of these switches enables and disables the band

Ahmed H. Khidre; H. A. El Sadek; H. F. Ragai

2009-01-01

458

Study of a printed circular disc monopole antenna for UWB systems  

Microsoft Academic Search

This paper presents a study of a novel monopole antenna for ultrawide-band (UWB) applications. Printed on a dielectric substrate and fed by a 50 ? microstrip line, a planar circular disc monopole has been demonstrated to provide an ultra wide 10 dB return loss bandwidth with satisfactory radiation properties. The parameters which affect the performance of the antenna in terms

Jianxin Liang; Choo C. Chiau; Xiaodong Chen; Clive G. Parini

2005-01-01

459

Object Tracking in a 2D UWB Sensor Network Cheng Chang  

E-print Network

network's communication system. This problem is related to multi-static radar. Position estimation usingObject Tracking in a 2D UWB Sensor Network Cheng Chang Electrical Engineering and Computer Science largely determined by the objects in the sensor network field. Collectively tracking the position

Sahai, Anant

460

Sequence Optimization-based UWB Receiver Jihad Ibrahim, Rekha Menon, and Dr. R.M. Buehrer  

E-print Network

- Noise is augmented · Alternative strategies: · Pre-Rake receiver: Rake combining at transmitter · Modify," IEEE Communications Letters, April 2006. ·R. Menon, J. Ibrahim, and R.M. Buehrer, "UWB Signal Detection Communication Conference, MILCOM 2005, October 2005 #12;

Southern California, University of

461

Compressive Sampling based Multiple Symbol Differential Detection for UWB IR Signals  

E-print Network

heavily stress the analog-to-digital converters (ADCs) causing high power consumption in the digitalCompressive Sampling based Multiple Symbol Differential Detection for UWB IR Signals Shahzad.s.gishkori@tudelft.nl; g.j.t.leus@tudelft.nl; vincenzo.lottici@iet.unipi.it Abstract--In this paper, a compressive sampling

Leus, Geert

462

Cognitive UWB-OFDM: Pushing Ultrawideband Beyond Its Limit via Opportunistic Spectrum Usage  

Microsoft Academic Search

In a continuously expanding wireless world, the number of ra- dio systems increases every day, and efficient spectrum usage be- comes a more significant requirement. Ultrawideband (UWB) and cognitive radio are two exciting technologies that offer new ap- proaches to the spectrum usage. The main objective of this paper is to shed the first light on the marriage of these

Hüseyin Arslan

2006-01-01

463

Airborne array aperture UWB UHF radar-motivation and system considerations  

Microsoft Academic Search

The paper discusses the necessity, feasibility and technology of FOPEN GMTI. It argues that this functionality may be one mode in a multi-function UWB UHF system, which jointly possesses the capabilities for air target MTI and high resolution FOPEN SAR. The radar platform may be a UAV or an aircraft, whereas it is proposed to use the push boom type

Hans Hellsten; Lars M. H. Ulander

1999-01-01

464

Techniques for clutter suppression in the presence of body movements during the detection of respiratory activity through UWB radars.  

PubMed

This paper focuses on the feasibility of tracking the chest wall movement of a human subject during respiration from the waveforms recorded using an impulse-radio (IR) ultra-wideband radar. The paper describes the signal processing to estimate sleep apnea detection and breathing rate. Some techniques to solve several problems in these types of measurements, such as the clutter suppression, body movement and body orientation detection are described. Clutter suppression is achieved using a moving averaging filter to dynamically estimate it. The artifacts caused by body movements are removed using a threshold method before analyzing the breathing signal. The motion is detected using the time delay that maximizes the received signal after a clutter removing algorithm is applied. The periods in which the standard deviations of the time delay exceed a threshold are considered macro-movements and they are neglected. The sleep apnea intervals are detected when the breathing signal is below a threshold. The breathing rate is determined from the robust spectrum estimation based on Lomb periodogram algorithm. On the other hand the breathing signal amplitude depends on the body orientation respect to the antennas, and this could be a problem. In this case, in order to maximize the signal-to-noise ratio, multiple sensors are proposed to ensure that the backscattered signal can be detected by at least one sensor, regardless of the direction the human subject is facing. The feasibility of the system is compared with signals recorded by a microphone. PMID:24514883

Lazaro, Antonio; Girbau, David; Villarino, Ramon

2014-01-01

465

Optical ultra-wide-band pulse bipolar and shape modulation based on a symmetric PM-IM conversion architecture.  

PubMed

A simple and feasible technique for ultra-wide-band (UWB) pulse bipolar modulation (PBM) and pulse shape modulation (PSM) in the optical domain is proposed and demonstrated. The PBM and PSM are performed using a symmetric phase modulation to intensity modulation conversion architecture, including a couple of phase modulators and an optical bandpass filter (OBPF). Two optical carriers, which are separately phase modulated by two appropriate electrical pulse patterns, are at the long- and short-wavelength linear slopes of the OBPF spectrum, respectively. The high-speed PBM and PSM without limit of chip length, polarity, and shape are implemented in simulation and are also verified by experiment. PMID:19838236

Wang, Shiguang; Chen, Hongwei; Xin, Ming; Chen, Minghua; Xie, Shizhong

2009-10-15

466

Subnanosecond hybrid modulator for UWB and HPM applications  

Microsoft Academic Search

A subnanosecond hybrid modulator with an output impedance of 45 ? and some systems based on this modulator have been tested. The modulator consists of a type SM-3NS driver with all-solid-state-switches, which is capable of producing 5-ns high-voltage pulses, and a pulse peaker with hydrogen spark gaps. The driver output stage contains an inductive energy store and a SOS-diode opening

M. I. Yalandin; S. K. Lyubutin; S. N. Rukin; V. G. Shpak; S. A. Shunailov; B. G. Slovikovsky

2002-01-01

467

A 0.18?m CMOS 802.15.4a UWB Transceiver for Communication and Localization  

Microsoft Academic Search

Recently, IEEE 802.15.4a has specified a UWB PHY for low-rate commutation with ranging capability for wireless personnel area and sensor network applications. Related work is reported on low-rate energy-efficient UWB radios. A combination of the burst position modulation (BPM) and binary phase shift keying (BPSK) is adopted. With different coding rate, bursts per symbol, and chips per burst, the mean

Yuanjin Zheng; M. Annamalai Arasu; King-Wan Wong; Yen Ju The; A. P. H. Suan; Duy Duong Tran; Wooi Gan Yeoh; Dim-Lee Kwong

2008-01-01

468

Design of CMOS integrated frequency synthesizers for ultra-wideband wireless communications systems  

E-print Network

of mobility by eliminating messy cables. Nowadays wireless network are dominated by narrow band systems like Bluetooth, Zigbee and IEEE 802.1a/b/g. Their limited data rate, no more than 54Mb/s, is insufficient to fast transfer large files and high...

Tong, Haitao

2009-05-15

469

CMOS Integrated Circuit Design for Ultra-Wideband Transmitters and Receivers  

E-print Network

compared to previously published design while keep relatively high gain and low noise at the same time. The designed sampling mixer shows unprecedented performance of 9-12dB voltage conversion gain, 16-25dB noise figure, and power consumption of only 21.6m...

Xu, Rui

2010-10-12

470

Ultra-Wideband Mitigation of Simultaneous Switching Noise Using Novel Planar Electromagnetic Bandgap Structures  

Microsoft Academic Search

A novel design of power\\/ground plane with planar electromagnetic bandgap (EBG) structures for suppressing simultaneous switching noise (SSN) is presented. The novel design is based on using meander lines to increase the effective inductance of EBG patches. A super cell EBG structure, comprising two different topologies on the same board, is proposed to extend the lower edge of the band.

Jie Qin; Omar M. Ramahi

2006-01-01

471

Respiration-rate estimation of a moving target using impulse-based ultra wideband radars.  

PubMed

Recently, Ultra-wide band signals have become attractive for their particular advantage of having high spatial resolution and good penetration ability which makes them suitable in medical applications. One of these applications is wireless detection of heart rate and respiration rate. Two hypothesis of static environment and fixed patient are considered in the method presented in previous literatures which are not valid for long term monitoring of ambulant patients. In this article, a new method to detect the respiration rate of a moving target is presented. The first algorithm is applied to the simulated and experimental data for detecting respiration rate of a fixed target. Then, the second algorithm is developed to detect respiration rate of a moving target. The proposed algorithm uses correlation for body movement cancellation, and then detects the respiration rate based on energy in frequency domain. The results of algorithm prove an accuracy of 98.4 and 97% in simulated and experimental data, respectively. PMID:22131095

Sharafi, Azadeh; Baboli, Mehran; Eshghi, Mohammad; Ahmadian, Alireza

2012-03-01

472

Ultra-Wideband, Dual-Polarized, Beam-Steering P-Band Array Antenna  

NASA Technical Reports Server (NTRS)

A dual-polarized, wide-bandwidth (200 MHz for one polarization, 100 MHz for the orthogonal polarization) antenna array at P-band was designed to be driven by NASA's EcoSAR digital beam former. EcoSAR requires two wide P-band antenna arrays mounted on the wings of an aircraft, each capable of steering its main beam up to 35deg off-boresight, allowing the twin radar beams to be steered at angles to the flight path. The science requirements are mainly for dual-polarization capability and a wide bandwidth of operation of up to 200 MHz if possible, but at least 100 MHz with high polarization port isolation and low cross-polarization. The novel design geometry can be scaled with minor modifications up to about four times higher or down to about half the current design frequencies for any application requiring a dual-polarized, wide-bandwidth steerable antenna array. EcoSAR is an airborne interferometric P-band synthetic aperture radar (SAR) research application for studying two- and three-dimensional fine-scale measurements of terrestrial ecosystem structure and biomass, which will ultimately aid in the broader study of the carbon cycle and climate change. The two 2×8 element Pband antenna arrays required by the system will be separated by a baseline of about 25 m, allowing for interferometry measurements. The wide 100-to- 200-MHz bandwidth dual-polarized beams employed will allow the determination of the amount of biomass and even tree height on the ground. To reduce the size of the patches along the boresight dimension in order to fit them into the available space, two techniques were employed. One technique is to add slots along the edges of each patch where the main electric currents are expected to flow, and the other technique is to bend the central part of the patch away from the ground plane. The latter also facilitates higher mechanical rigidity. The high port isolation of more than 40 dB was achieved by employing a highly symmetrical feed mechanism for each pair of elements: three apertures coupling to the patch elements were placed along the two symmetry lines of the antenna element pair. Two apertures were used in tandem to excite two of the stacked patch elements for one polarization; the other was used to excite one element from one side and the other element from the other side, opposite in phase, taking care of the remaining polarization. The apertures narrow down to a small gap where they are excited by a crossing microstrip line to prevent any asymmetrical excitation of the two sides of the aperture gap, minimizing port-to-port coupling. Using patches that are non-planar leads to higher mechanical rigidity and smaller patch sizes to fit into the available space. Aperture coupling minimizes direct metal-to-metal connections. Using an aperture coupling feed mechanism results in a feed network for two antenna elements with a total of three feed points, plus one simple in-phase combiner to reduce it to two ports. It greatly reduces the complexity of the alternative, but more conventional, way of feeding a pair of two dual-polarized elements with high port isolation.

duToit, Cornelis

2014-01-01

473

Short range, ultra-wideband radar with high resolution swept range gate  

DOEpatents

A radar range finder and hidden object locator is based on ultra-wide band radar with a high resolution swept range gate. The device generates an equivalent time amplitude scan with a typical range of 4 inches to 20 feet, and an analog range resolution as limited by a jitter of on the order of 0.01 inches. A differential sampling receiver is employed to effectively eliminate ringing and other aberrations induced in the receiver by the near proximity of the transmit antenna, so a background subtraction is not needed, simplifying the circuitry while improving performance. Uses of the invention include a replacement of ultrasound devices for fluid level sensing, automotive radar, such as cruise control and parking assistance, hidden object location, such as stud and rebar finding. Also, this technology can be used when positioned over a highway lane to collect vehicle count and speed data for traffic control. 14 figs.

McEwan, T.E.

1998-05-26

474

Short range, ultra-wideband radar with high resolution swept range gate  

DOEpatents

A radar range finder and hidden object locator is based on ultra-wide band radar with a high resolution swept range gate. The device generates an equivalent time amplitude scan with a typical range of 4 inches to 20 feet, and an analog range resolution as limited by a jitter of on the order of 0.01 inches. A differential sampling receiver is employed to effectively eliminate ringing and other aberrations induced in the receiver by the near proximity of the transmit antenna, so a background subtraction is not needed, simplifying the circuitry while improving performance. Uses of the invention include a replacement of ultrasound devices for fluid level sensing, automotive radar, such as cruise control and parking assistance, hidden object location, such as stud and rebar finding. Also, this technology can be used when positioned over a highway lane to collect vehicle count and speed data for traffic control.

McEwan, Thomas E. (Livermore, CA)

1998-05-26

475

The National Geoelectromagnetic Facility - an open access resource for ultra wideband electromagnetic geophysics (Invited)  

NASA Astrophysics Data System (ADS)

At present, the US academic community has access to two national electromagnetic (EM) instrument pools that support long-period magnetotelluric (MT) equipment suitable for crust-mantle scale studies. The requirements of near surface geophysics, hydrology, glaciology, as well as the full range of crust and mantle investigations require development of new capabilities in data acquisition with broader frequency bandwidth than these existing units, increased instrument numbers, and concomitant developments in 3D/4D data interpretation. NSF Major Research Instrumentation support has been obtained to meet these requirements by developing an initial set of next-generation instruments as a National Geoelectromagnetic Facility (NGF), available to all PIs on a cost recovery basis, and operated by Oregon State University (OSU). In contrast to existing instruments with data acquisition systems specialized to operate within specific frequency bands and for specific electromagnetic methods, the NGF model "Zen/5" instruments being co-developed by OSU and Zonge Research and Engineering Organization are based on modular receivers with a flexible number of digital and analog input channels, designed to acquire EM data at dc, and from frequencies ranging from micro-Hz to MHz. These systems can be deployed in a compact, low power configuration for extended deployments (e.g. for crust-mantle scale experiments), or in a high frequency sampling mode for near surface work. The NGF is also acquiring controlled source EM transmitters, so that investigators may carry out magnetotelluric, audio-MT, radiofrequency-MT, as well as time-domain/transient EM and DC resistivity studies. The instruments are designed to simultaneously accommodate multiple electric field dipole sensors, magnetic fluxgates and induction coil sensors. Sample rates as high as 2.5 MHz with resolution between 24 and 32 bits, depending on sample rate, are specified to allow for high fidelity recording of waveforms. The NGF is accepting instrument use requests from investigators planning electromagnetic surveys via webform submission on its web site ngf.coas.oregonstate.edu. The site is also a port of entry to request access to the 46 long period magnetotelluric instruments also operated by OSU as national instrument pools. Cyberinfrastructure support is available to investigators, including field computers, EM data processing software, and access to a hybrid CPU-GPU parallel computing environment, currently configured with dual Intel Westmere hexacore CPUs and 960 NVidia Tesla and 1792 Nvidia Fermi GPU cores. The capabilities of the Zen/5 receivers will be presented, with examples of data acquired from a recent shallow water marine controlled source experiment conducted in coastal Oregon as part of an effort to locate a buried submarine pipeline, using a 1.1 KW 256 Hz signal source imposed on the pipeline from shore. A Zen/5 prototype instrument, modified for marine use through support by the Oregon Wave Energy Trust, demonstrated the marine capabilities of the NGF instrument design.

Schultz, A.; Urquhart, S.; Slater, M.

2010-12-01

476

Progress In Electromagnetics Research, Vol. 121, 121139, 2011 LOW-PROFILE DIRECTIONAL ULTRA-WIDEBAND AN-  

E-print Network

is presented. The antenna can be fabricated on a printed circuit board (PCB). On one side of the PCB, it has wavelength at the lowest frequency). In order to validate the design, a prototype is also fabricated at Vil- lanova University. A real-time see-through-wall radar system [8] based on FPGA is designed

Doran, Simon J.

477

Group delay in THz spectroscopy with ultra-wideband log-spiral antennae  

E-print Network

We report on the group delay observed in continuous-wave terahertz spectroscopy based on photomixing with phase-sensitive homodyne detection. We discuss the different contributions of the experimental setup to the phase difference \\Delta\\phi(\

Langenbach, M; Mayorga, I Cámara; Deninger, A; Thirunavukkuarasu, K; Hemberger, J; Grüninger, M

2014-01-01

478

On-chip programmable ultra-wideband microwave photonic phase shifter and true time delay unit.  

PubMed

We proposed and experimentally demonstrated an ultra-broadband on-chip microwave photonic processor that can operate both as RF phase shifter (PS) and true-time-delay (TTD) line, with continuous tuning. The processor is based on a silicon dual-phase-shifted waveguide Bragg grating (DPS-WBG) realized with a CMOS compatible process. We experimentally demonstrated the generation of delay up to 19.4 ps over 10 GHz instantaneous bandwidth and a phase shift of approximately 160° over the bandwidth 22-29 GHz. The available RF measurement setup ultimately limits the phase shifting demonstration as the device is capable of providing up to 300° phase shift for RF frequencies over a record bandwidth approaching 1 THz. PMID:25361309

Burla, Maurizio; Cortés, Luis Romero; Li, Ming; Wang, Xu; Chrostowski, Lukas; Azaña, José

2014-11-01

479

Development of an Ultra-Wideband Radar System for Vehicle Detection at Railway Crossings  

E-print Network

a video detection system in a test at a crossing in Maywood, Illinois. If the test is successful According to statistics compiled during 1994 by the Federal Railroad Administration, 610 people were killed or that they can beat the train. One method being studied by the railroad industry to stop these drive

Kansas, University of

480

Ultra-wideband amplifiers based on Bi 2O 3-EDFAs  

NASA Astrophysics Data System (ADS)

We demonstrate broadband amplification over (C?+?L)-band or extended L-band using fusion-spliceable Bi 2O 3-based erbium doped fiber (EDF). A power conversion efficiency (PCE) of 39% is achieved. In a single-stage amplifier we achieved a 3 dB bandwidth of 75 nm. In addition we showed very low four-wave mixing in an extended L-band amplifier by reducing the length of fiber required to a few meters.

Ohara, S.; Sugimoto, N.; Ochiai, K.; Hayashi, H.; Fukasawa, Y.; Hirose, T.; Nagashima, T.; Reyes, M.

2004-10-01

481

Ultra-wideband all-fiber tunable Tm/Ho-co-doped laser at 2 ?m.  

PubMed

We demonstrate an all-fiber tunable Tm/Ho-codoped laser operating in the 2 ?m wavelength region. The wavelength tuning range of the Tm/Ho-codoped fiber laser (THFL) with 1-m length of Tm/Ho-codoped fiber (THDF) was from 1727 nm to 2030 nm. Efficient short wavelength operation and ultra-wide wavelength tuning range of 303 nm were both achieved. To the best of our knowledge, this is the broadest tuning range that has been reported for an all-fiber rare-earth-doped laser to date. By increasing the THDF length to 2 m, the obtainable wavelength of the THFL was further red-shifted to the range from 1768 nm to 2071 nm. The output power of the THFL was scaled up from 1810 nm to 2010 nm by using a stage of Tm/Ho-codoped fiber amplifier (THFA), which exhibited the maximum slope efficiency of 42.6% with output power of 408 mW at 1910 nm. PMID:25401631

Xue, Guanghui; Zhang, Bin; Yin, Ke; Yang, Weiqiang; Hou, Jing

2014-10-20

482

An Ultra-Wideband Receiver and Spectrometer for 74--110 GHz  

NASA Astrophysics Data System (ADS)

A receiver system that covers the widest instantaneous bandwidth ever utilized by an astronomical heterodyne receiver is nearly complete. The entire 74--110.5 GHz band will be covered with a low noise frontend and a backend spectrometer having 31 MHz resolution. The receiver is intended for astronomical use in searching for the highly redshifted spectral lines from galaxies of unknown redshift. The receiver uses InP MMIC based low noise amplifiers operated at 20 K, and operates with dual polarization feeds. The two receivers used with each feed are combined using a full band orthomode transition. Two such feeds are used in conjunction with a beam switch to maintain one dual polarized beam on the source at all times. The backend spectrometer is an analog autocorrelator built using very low cost microwave and analog/digital components.

Erickson, N.; Narayanan, G.; Goeller, R.; Grosslein, R.

2007-10-01

483

Progress towards ultra-wideband AlGaN/GaN MMICs  

NASA Astrophysics Data System (ADS)

The AlGaN/GaN material system possesses fundamental properties that make it an ideal candidate for high power microwave devices. This has been known for over 30 years, however, significant device progress has only come recently. This article gives a summary of AlGaN/GaN electronic device progress, outlines future device directions, and discusses the use of these new devices in power amplifier circuits.

Zolper, J. C.

1999-08-01

484

Power-efficient ultra wideband LNAs for the world's largest radio telescope  

NASA Astrophysics Data System (ADS)

This paper reports two Low Noise Amplifiers (LNA) for Aperture Array system of the international Square Kilometre Array (SKA) project. LNA design for SKA is a step change in traditional LNA design approach for radio astronomy applications as the defining aspects of performance are low noise along with low power consumption and adequate gain. The LNAs are designed, fabricated and characterised for frequency range of 20 -1000 MHz. One LNA has single ended input to single ended output configuration (LNA1) while the other LNA has balanced input to single ended output (LNA2). The S-parameter, noise figure (NF) and large signal response of the LNAs are measured at room temperature. Both LNAs show flat gain of higher than 30 dB over specified frequency range. Average NF values of LNA1 and LNA2 are 0.55 dB and 0.75 dB respectively. Mixed mode S-parameter response based on theoretical analysis of differential configuration is presented. The LNAs have exceptionally low power consumption of less than 25 mW; 20 times lower than the other reported LNAs available for the SKA and also covering complete frequency band with less than 1 dB NF. Therefore implication of these LNAs is a significant step forward as the projected number of LNAs required for the lower frequency band of SKA Aperture Array system is 5,600,000 (Dewdney et al., Proc. IEEE 97(8), 1482-1496, 2009; Faulkner et al. 2010).

Panahi, M.; Bhaumik, S.; George, D.

2014-10-01

485

An analog approach to interference suppression in ultra-wideband receivers  

E-print Network

. The Operational Transconductance Amplifier (OTA) is the predominant building block in the design of the notch filter. In many cases, OTAs must handle input signals with large common mode swings. A new scheme for achieving rail-to-rail input to an OTA is introduced...

Fischer, Timothy W.

2007-09-17

486

Detection and Interference Suppression for Ultra-Wideband Signaling with Analog Processing  

E-print Network

to quantization in the presence of strong narrowband interference is significant. This motivates our design amplifiergain. This front end, follow,edby either a matched filter or one bit AID, yields acceptable performance even with strong narrowband interference. 1. INTRODUCTION There is growing interest in commercial ultra

Dabeer, Onkar

487

Coplanar Printed-Circuit Antenna With Band-Rejection Elements For Ultra-Wideband Filtenna Applications  

E-print Network

Introduction Filtennas consist of wideband antenna structures, which incorporate narrowband filter elements) technology in the 3.1 - 10.6 GHz range, it is essential that certain narrowband services be appropriately. This paper presents three coplanar filtenna designs, which incorporate, first, a coplanar filter in the feed

Bornemann, Jens

488

Time Reversal with MISO for Ultra-Wideband Communications: Experimental Results (invited paper)  

E-print Network

, control of home appliances, search-and-rescue, family communications and supervision of children with the channel impulse response (CIR) (from Rx to Tx), , at the m-th transmitter antenna. Second, the ( )f t x

Qiu, Robert Caiming

489

Graphene as a high impedance surface for ultra-wideband electromagnetic waves  

SciTech Connect

The metals are regularly used as reflectors of electromagnetic fields emitted by antennas ranging from microwaves up to THz. To enhance the reflection and thus the gain of the antenna, metallic high impedance surfaces (HIS) are used. HIS is a planar array of continuous metallic periodic cell surfaces able to suppress surface waves, which cause multipath interference and backward radiation in a narrow bandwidth near the cell resonance. Also, the image currents are reduced, and therefore the antenna can be placed near the HIS. We demonstrate that graphene is acting as a HIS surface in a very large bandwidth, from microwave to THz, suppressing the radiation leakages better than a metal.

Aldrigo, Martino; Costanzo, Alessandra [Department of Electrical, Electronic, and Information Engineering “Guglielmo Marconi” – DEI, University of Bologna, Viale del Risorgimento, 2, 40132 Bologna (Italy); Dragoman, Mircea [National Institute for Research and Development in Microtechnology (IMT), P.O. Box 38-160, 023573 Bucharest (Romania); Dragoman, Daniela [Department of Physics, University of Bucharest, P.O. Box MG-11, 077125 Bucharest (Romania)

2013-11-14

490

Fabrication of CPW-Fed Fractal Antenna for UWB Applications with Omni-Directional Patterns  

PubMed Central

Novel and compact CPW-fed antennas are proposed comprised of a fractal patch and modified ground-plane. The ground-plane is truncated at the center and includes dielectric notches at its side to enhance the antenna's impedance bandwidth. The dimensions of the notches effectively control the upper and lower band edges of the antenna. The optimized antenna operates across 2.95–12.81?GHz for S11 ? ?10?dB. Omnidirectional radiation pattern is achieved over the full UWB frequency range. The miniaturized antenna has a total size of 14 × 18 × 1?mm3. The characteristics of the proposed antenna are suitable for UWB wireless communication requiring low profile antennas. PMID:24672314

Sedghi, Tohid; Jalali, Mahdi; Aribi, Tohid

2014-01-01

491

Simulation and signal processing of through wall UWB radar for human being's periodic motions detection  

NASA Astrophysics Data System (ADS)

The human's Micro-Doppler signatures resulting from breathing, arm, foot and other periodic motion can provide valuable information about the structure of the moving parts and may be used for identification and classification purposes. In this paper, we carry out simulate with FDTD method and through wall experiment with UWB radar for human being's periodic motion detection. In addition, Advancements signal processing methods are presented to classify and to extract the human's periodic motion characteristic information, such as Micro-Doppler shift and motion frequency. Firstly, we apply the Principal Component Analysis (PCA) with singular value decomposition (SVD) to denoise and extract the human motion signal. Then, we present the results base on the Hilbert-Huang transform (HHT) and the S transform to classify and to identify the human's micro-Doppler shift characteristics. The results demonstrate that the combination of UWB radar and various processing methods has potential to detect human's Doppler signatures effectively.

Li, Jing; Liu, Fengshan; Xu, Penglong; Zeng, Zhaofa

2013-05-01

492

Fabrication of CPW-fed fractal antenna for UWB applications with Omni-directional patterns.  

PubMed

Novel and compact CPW-fed antennas are proposed comprised of a fractal patch and modified ground-plane. The ground-plane is truncated at the center and includes dielectric notches at its side to enhance the antenna's impedance bandwidth. The dimensions of the notches effectively control the upper and lower band edges of the antenna. The optimized antenna operates across 2.95-12.81 GHz for S11 ? -10 dB. Omnidirectional radiation pattern is achieved over the full UWB frequency range. The miniaturized antenna has a total size of 14 × 18 × 1 mm(3). The characteristics of the proposed antenna are suitable for UWB wireless communication requiring low profile antennas. PMID:24672314

Sedghi, Tohid; Jalali, Mahdi; Aribi, Tohid

2014-01-01

493

UWB Dual-Linear Polarization Dielectric Horn Antennas as Reflector Feeds  

Microsoft Academic Search

An ultrawide bandwidth (UWB) dielectric horn antenna (DHA) design is presented. This DHA design provides dual-linear polarization with similar Eand H-plane patterns and a near-constant beamwidth from 2 to 18 GHz. The fixed phase center makes it an excellent candidate for feeding a reflector. The DHA is composed of a resistively terminated broadband field launcher, a solid dielectric horn body,

Kwan-Ho Lee; Chi-Chih Chen; Robert Lee

2007-01-01

494

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