Sample records for ultra wideband wireless

  1. Ultra-wideband wireless communications

    Microsoft Academic Search

    Weihua Zhuang; Qi Bi

    2003-01-01

    Summary Ultra-wideband (UWB) communication techniques have attracted a great interest in both academia and industry in the past few years for applications in short-range wireless mobile systems. This is due to the potential advantages of UWB transmissions such as low power, high rate, immunity to multipath propagation, less complex transceiver hardware, and low interference. However, tremendous R&D efforts are required

  2. Signal Processing Algorithms for Ultra-Wideband Wireless Communications

    E-print Network

    Langendoen, Koen

    . . . . . . . . . . . . . . . . . . 12 2.1.2 Standardization and applications . . . . . . . . . . . . . . . . . 14 2.1.3 UWB channelsSignal Processing Algorithms for Ultra-Wideband Wireless Communications PROEFSCHRIFT ter to Ultra-Wideband Radio . . . . . . . . . . . . . . . . 11 2.1.1 Impulse Radio Ultra-Wideband

  3. System considerations for ultra-wideband wireless networks

    Microsoft Academic Search

    Matthew L. Welborn

    2001-01-01

    This paper describes some general properties of ultra-wideband (UWB) communications systems and identify characteristics of UWB technology that make it an attractive solution for indoor wireless networks. This paper describes a number of different modulation and coding schemes that are possible for UWB communication systems. Based on results in the literature and additional analysis here, approaches likely to provide the

  4. Microstrip bandpass filters for Ultra-Wideband (UWB) wireless communications

    Microsoft Academic Search

    Ching-Luh Hsu; Fu-Chieh Hsu; Jen-Tsai Kuo

    2005-01-01

    A new technique is developed for designing a composite microstrip bandpass filter (BPF) with a 3 dB fractional bandwidth of more than 100%. The BPF is suitable for ultra-wideband (UWB) wireless communications. The design utilizes embedding individually designed highpass structures and lowpass filters (LPF) into each other, followed by an optimization for tuning in-band performance. The stepped-impedance LPF is employed

  5. A high speed image transmission system for ultra-wideband wireless links

    E-print Network

    Liang, Helen He

    2009-01-01

    Ultra-wideband (UWB) communication is an emerging technology that offers short range, high data rate wireless transmission, with low power consumption and low consumer cost. Operating in the 3.1 GHz - 10.6 GHz frequency ...

  6. Abstract--Ultra-wideband (UWB) has been proposed for physical layer standard for high speed wireless personal area

    E-print Network

    Paris-Sud XI, Université de

    Abstract-- Ultra-wideband (UWB) has been proposed for physical layer standard for high speed to traditional wireless technologies in WPANs. This paper describes low complexity high data rate Ultra- wideband related to faults associated with wiring (cutting, shearing, false contacts). Indeed, Ultra Wideband [1

  7. Architecture of an ultra wideband wireless body area network for medical applications

    Microsoft Academic Search

    Raúl Chávez-Santiago; Ali Khaleghi; Ilangko Balasingham; Tor A. Ramstad

    2009-01-01

    The utilization of wireless technology in traditional medical services provides patients with enhanced mobility. This has a positive effect on the recovery speed of a patient after major surgical procedures or prolonged illness. This paper presents the architecture of a healthcare wireless network that exploits the capabilities of ultra wideband technology (UWB) for medical sensing and in-body tracking and imaging.

  8. UltraUltra--Wideband (UWB)Wideband (UWB) Wireless CommunicationsWireless Communications

    E-print Network

    Qiu, Robert Caiming

    Devices w/ Integral Wireless Modules - Embedded Apps Telematics / Telemetry Ericsson R380 PDQ Smart Phone Combining Air Interface3G & UWB Combining Air Interface W LA N U W B Not to Scale 1 Wide Area cell = ~10 000Open Research IssuesOpen Research Issues · System and protocol design · Analysis, performance modeling · Test

  9. Impact Of Ultra Wideband (Uwb) Radio Range On Wireless Sensor Networks

    E-print Network

    Ha, Dong S.

    Impact Of Ultra Wideband (Uwb) Radio Range On Wireless Sensor Networks Woo Cheol Chung, Nathaniel J by regulations, so they must extend radio range through other means. We derive the limits of I-UWB radio range that includes the effects of data rate, signal-to-noise ratio, antenna gains at the transmitter and the receiver

  10. Ultra-Wideband Technology for Short or Medium-Range Wireless Communications

    Microsoft Academic Search

    Jeff Foerster; Evan Green; Srinivasa Somayazulu; David Leeper

    2001-01-01

    Ultra-Wideband (UWB) technology is loosely defined as any wireless transmission scheme that occupies a bandwidth of more than 25% of a center frequency, or more than 1.5GHz. The Federal Communications Commission (FCC) is currently working on setting emissions limits that would allow UWB communication systems to be deployed on an unlicensed basis following the Part 15.209 rules for radiated emissions

  11. Ultra-wideband Communications

    Microsoft Academic Search

    K Waltjen; C Romero; S Azevedo; F Dowla; A Spiridon; D Benzel; P Haugen

    2004-01-01

    Many applications in wireless communications often require short-range systems capable of rapidly collecting data and transmitting it reliably. Commercial communication systems operate in fixed frequency bands and are easily detectable and are prone to jamming by the enemy, among other shortcomings. The new ultra-wideband (UWB) communications system in the 3.1 to 10 GHz band is of significant interest to a

  12. Performance comparison of ultra-wideband time-hopping, DSSS and OFDM multiple access schemes for wireless sensor networks

    Microsoft Academic Search

    Naveel Riaz; M. Ghavami

    2006-01-01

    Ultra-wideband (UWB) radio communication sys- tems operate using extremely short duration base-band pulses. This paper compares the performance of three competing multi- ple access modulation schemes that have been proposed for appli- cation to UWB based wireless sensor networks. These multiple access schemes are ultra-wideband Time-Hopping (TH-UWB), Direct Sequence Spread Spectrum (DSSS-UWB) and Orthogonal Frequency Division Multiplexing (OFDM-UWB). Each system

  13. Self Organization of Wireless Sensor Networks Using Ultra-Wideband Radios

    SciTech Connect

    Nekoogar, F; Dowla, F; Spiridon, A

    2004-07-19

    Ultra-wideband (UWB) technology has proven to be useful in short range, high data rate, robust, and low power communications. These features can make UWB systems ideal candidates for reliable data communications between nodes of a wireless sensor network (WSN). However, the low powered UWB pulses can be significantly degraded by channel noise, inter-node interference, and intentional jamming. In this paper we present a novel interference suppression technique for UWB based WSNs that promises self-organization in terms of power conservation, scalability, and channel estimation for the entire distributed network.

  14. Monocycle shapes for ultra wideband system

    Microsoft Academic Search

    Xiaomin Chen; Sqfe Kiaei

    2002-01-01

    Ultra Wideband (UWB) is a promising technique for wireless communications. It is a carrier-free (base-band) technique, which will greatly reduce the complexity and cost of the transceiver. In contrast with the conventional communication systems using the \\

  15. Ultra-wideband Communications

    SciTech Connect

    Waltjen, K; Romero, C; Azevedo, S; Dowla, F; Spiridon, A; Benzel, D; Haugen, P

    2004-02-06

    Many applications in wireless communications often require short-range systems capable of rapidly collecting data and transmitting it reliably. Commercial communication systems operate in fixed frequency bands and are easily detectable and are prone to jamming by the enemy, among other shortcomings. The new ultra-wideband (UWB) communications system in the 3.1 to 10 GHz band is of significant interest to a number of Lawrence Livermore National Laboratory (LLNL) programs including the Nonproliferation, Arms Control, and International Security (NAI) Directorate. Ultra-Wideband (UWB) technology has received a significant degree of attention from communications industry since the Federal Communications Commission (FCC) rulings in February 2002. According to FCC, UWB signals have fractional bandwidth (B{sub f}) of 20% or larger at -10 dB cut-off frequencies, with minimum bandwidth of 500 MHz. Unlike traditional communication systems, UWB systems modulate carrier-less, short-duration (picosec to nanosec) pulses to transmit and receive information. A number of programmatic problems at LLNL, particularly in the NAI and other national security Directorates, require collecting information from multiple sensors distributed over a local area. The information must be collected covertly and by wireless means. The sensors produce data using low power devices and the communication link must operate in severe multipath environments over tens of meters; often the links must be channelized to handle multiple sensors. The communications links between these sensors is a critical issue in the development of LLNL programs to demonstrate distributed sensor network performance in real-time. In summary, such systems must be robust; have a low probability of detection and intercept; employ low-power, small-size hardware; and interface easily with other systems for analysis or to establish long-distance links. The purpose of this work was to develop a new UWB radio-frequency (RF) communications system for the UWB RF band. In this project we addressed the need for robust UWB communication systems with low-power, small-size sensor communication hardware. Our research results have successfully addressed these issues and we developed UWB radios and interfaced these radios with repeater radios for longer distance links. In particular, research and development challenges included signal processing and communication design problems, including developing novel UWB modulation and demodulation schemes, link budget analysis for ultra-wideband signals, multipath mitigation, short-pulse signal synchronization, and building real working radios. We have had a significant degree of success in solving these technical challenges. As a result, several programmatic efforts have spun off from our R&D work in FY04.

  16. Ultra wideband for wireless real-time monitoring of neural signals.

    PubMed

    Tarín, Cristina; Traver, Lara; Martí, Paula; Cardona, Narcís

    2009-06-01

    Performance of an ultra wideband (UWB) wireless system for real-time neural signal monitoring is evaluated by comparing spiking characteristics between transmitted and received signals for different experimental set-ups. Spike detection quality is selected as the main spiking characteristic of evaluated signals. Results are presented in receiver-operating characteristics and area-under-the-curve (AUC). In order to assess spike detection quality, a set of artificially generated neural signals is constructed from real neural recordings such that the ground truth is known. Data analysis shows how channel signal-to-noise-ratio (SNR) variation affects AUC in different signal SNR cases. Signals with low SNRs get less affected by reduced channel SNRs than those with higher SNR. Increasing bit error rate modifies spiking characteristics such that an under-estimation of the spiking frequency occurs due to spike losses. For practical application of real-time neural signal monitoring, UWB seems to offer best transmission conditions in a near-body environment. PMID:19340472

  17. An ultra-wideband transceiver architecture for low power, low rate, wireless systems

    Microsoft Academic Search

    Ian D. O'Donnell; Robert W. Brodersen

    2005-01-01

    This paper presents the system architecture, modeling, and design constraints for a baseband, integrated, CMOS, impulse ultra-wideband transceiver targeting very low power consumption on the order of 1 mW. Intended for a sensor network application, the radio supports low communication rates (?100 kpbs) and ranging capabilities over short distances (?10 m). Based on a \\

  18. Chirp Frequency-Translated Reference Ultra-Wideband (UWB) Wireless Communication System

    Microsoft Academic Search

    Zhang Jian; Hu Han-Ying; Liu Luo-Kun; Wang Tao

    2008-01-01

    A chirp frequency-translated reference ultra-wideband system is proposed based on the time-domain and code-domain transmitted-reference impulse radio UWB systems. Mathematic derivation and simulation results show that while this system has similar performance to pulse-based UWB system without losing the merits, it has the advantages of chirp communication system as well. Meanwhile, this system not only offers a solution of simple

  19. AN INTEGRATED, LOW POWER, ULTRA-WIDEBAND TRANSCEIVER ARCHITECTURE FOR LOW-RATE, INDOOR WIRELESS SYSTEMS

    Microsoft Academic Search

    Ian D. O'Donnell; Mike S. W. Chen; Stanley B. T. Wang; Robert W. Brodersen

    This paper describes the system architecture and circuit design constraints for a proposed Ultra-Wideband radio transceiver. Targeting a sensor network application, the radio supports peer-to-peer communication at greater than 100kbps over 5 meters with a 1mW total (TX+RX) power budget. A narrow pulse (approximately 1ns wide) is trans- mitted using simple digital switches; spreading the energy over a Gigahertz of

  20. Planar printed monopole antennas for ultra-wideband\\/multi-band wireless systems

    Microsoft Academic Search

    Chao Deng; Lu Li; Qingge Gong; Dianfu Zhan; Yongxing Zou

    2011-01-01

    An ultra-wideband (UWB) antenna with band rejection of WLAN\\/WiMAX systems and a tri-band antenna for WLAN\\/WiMAX applications are, respectively, proposed by the band-rejected design of the coplanar waveguide (CPW) fed circular monopole antenna. In order to notch the frequency bands covered by WLAN and WiMAX, two pieces of bent slotline are loaded at the patch bottom of the conventional UWB

  1. A study of the ultra-wideband wireless propagation channel and optimum UWB receiver design

    Microsoft Academic Search

    Robert C. Qiu

    2002-01-01

    The paper addresses a crucial point in ultra-wideband (UWB) radio wave propagation, which is the spatial-temporal resolution of scattering objects into multiple frequency-dependent scattering centers. The effect contributes to the widely observed temporal dispersion of pulse-shaped transmit signals and their distortion, respectively. Particularly the latter is explained by (multiple) diffraction of the incident wave, leading to (multiple) band-limited impulse responses

  2. A fast acquisition system for ultra-wideband wireless multiple-access communications

    Microsoft Academic Search

    Yassine Salih Alj; Charles Despins; Sofiene Affes

    2009-01-01

    The fast and accurate timing acquisition of short ultra-wideband (UWB) pulse shapes and, implicitly, the required high sampling rates play a significant role in UWB receiver-structure design and create challenges for signal acquisition under non-ideal conditions. Furthermore, the pulse shape is seen as one of the key factors influencing the performance of UWB systems. While fulfilling the power-spectral-density emission requirements,

  3. Ultra-wideband digital baseband

    E-print Network

    Blázquez-Fernández, Raúl, 1975-

    2006-01-01

    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 ...

  4. A framework for cooperative localization in ultra-wideband wireless networks

    E-print Network

    Lien, Jaime

    2007-01-01

    Location-aware technologies have the potential to revolutionize computing, cellular services, sensor networks, and many other commercial, military, and social applications. In wireless networks, accurate information about ...

  5. State of arts in ultra wideband (UWB) wireless technology and global harmonization

    Microsoft Academic Search

    Ryuji KOHNO

    2004-01-01

    As a center of mobile multimedia of the 21st century, it is very much looking forward to explosion of R&D and business of various wireless communication systems. In order to maintain advancement of communications and its related industries in Japan, there is a demand to keep creating new high technologies and theories and to educate a high level of experts

  6. A Compact Ultra-Wideband Antenna for Time-and Frequency-Domain Applications

    E-print Network

    Sarabandi, Kamal

    A Compact Ultra-Wideband Antenna for Time- and Frequency- Domain Applications Nader Behdad the early investigations on ultra-wideband (UWB) wireless systems, they have found a wide range, communication systems for military, and UWB short pulse radars for automotive and robotics applications to name

  7. On diversity improvements for ultra wideband communication systems

    Microsoft Academic Search

    Keni Popovski

    2008-01-01

    The wireless communications arena consists of a wide range of products and services, each with a specific target market and approach. Having characteristic advantages and disadvantages, all attempt to increase their market share through diversification and innovation. Ultra wideband (UWB) is a recent entry into the commercial short-range communications world, differentiated by its sparse spectral profile and low peak power

  8. A survey of antennas for ultra-wideband applications

    Microsoft Academic Search

    Maysam Sarfaraz; Amir Shirkhodaie

    2008-01-01

    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

  9. Ultra-wideband communications: an idea whose time has come

    Microsoft Academic Search

    Liuqing Yang; G. B. Giannakis

    2004-01-01

    Ultra-wideband (UWB) radio is a fast emerging technology with many unique attractive features that promotes major advances in wireless communications, networking, radar, imaging, and positioning systems. Research in UWB is still in its infancy stages, offering limited resources in handling the challenges facing the UWB communications. Understanding the unique properties and challenges of UWB communications as well as its application

  10. ISI-free pulses for high-data-rate ultra-wideband wireless systems

    E-print Network

    Chaturvedi, A K

    ´erence intersymbole pour les syst`emes sans fil ultra large bande `a haut d´ebit Ziaul Hasan, Umesh Phuyal, V. Yadav of British Columbia, Vancouver, B.C. V6T 1Z4. E-mail: {ziaulh, phuyal, vijayb}@ece.ubc.ca. V. Ya- dav and A algorithm [3]. The power spectrum of these pulses fits the FCC spectral mask and Ziaul Hasan, Umesh Phuyal

  11. A non-coherent ultra-wideband receiver : algorithms and digital implementation

    E-print Network

    Vitavasiri, Sinit

    2007-01-01

    Ultra-wideband (UWB) communication is an emerging technique for wireless transmission in the 3.1-10.6 GHz unlicensed band with signal bandwidths of 500 MHz or greater. A non-coherent receiver based on energy collection ...

  12. An energy efficient sub-threshold baseband processor architecture for pulsed ultra-wideband communications

    E-print Network

    Sze, Vivienne

    2006-01-01

    Ultra-wideband (UWB) communications is currently being explored as a medium for high-data-rate last-meter wireless links. Accordingly, there has been much interest in integrating UWB radios onto battery-operated devices, ...

  13. A platform for ultra wideband communication systems

    E-print Network

    Ackerman, Nathan (Nathan Joseph)

    2005-01-01

    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 ...

  14. Hemispheric ultra-wideband antenna.

    SciTech Connect

    Brocato, Robert Wesley

    2006-04-01

    This report begins with a review of reduced size ultra-wideband (UWB) antennas and the peculiar problems that arise when building a UWB antenna. It then gives a description of a new type of UWB antenna that resolves these problems. This antenna, dubbed the hemispheric conical antenna, is similar to a conventional conical antenna in that it uses the same inverted conical conductor over a ground plane, but it also uses a hemispheric dielectric fill in between the conductive cone and the ground plane. The dielectric material creates a fundamentally new antenna which is reduced in size and much more rugged than a standard UWB conical antenna. The creation of finite-difference time domain (FDTD) software tools in spherical coordinates, as described in SAND2004-6577, enabled this technological advance.

  15. Ultra-wideband directional sampler

    DOEpatents

    McEwan, T.E.

    1996-05-14

    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.

  16. Wideband local access: wireless LAN and wireless ATM

    Microsoft Academic Search

    K. Pahlavan; A. Zahedi; P. Krishnamurthy

    1997-01-01

    An overview of the status of wideband wireless local access technologies is provided. Service scenarios and availability of the market and products for wireless LAN and wireless ATM technologies are discussed. Similarities among IEEE 802.11 and HIPERLAN standards for wireless LANs and the developing prototypes for wireless ATM are evaluated. An update on the status of the available unlicensed bands

  17. Ultra-wideband impedance sensor

    DOEpatents

    McEwan, Thomas E. (Livermore, CA)

    1999-01-01

    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.

  18. Ultra-wideband impedance sensor

    DOEpatents

    McEwan, T.E.

    1999-03-16

    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.

  19. Compact Ultra-Wideband Antenna for Portable Devices

    NASA Astrophysics Data System (ADS)

    Kasi, B.; Ping, L. C.; Chakrabarty, C. K.

    2013-06-01

    This article presents a compact ultra-wideband (UWB) antenna for wireless dongle devices. The printed monopole antenna, with the size of 15 mm × 30 mm, has an impedance bandwidth ranges from 2.9 to 13 GHz. The proposed structure comprises of a hexagonal radiator fed by a microstrip line with a modified ground plane. Such a design can be easily integrated with wireless universal serial bus (USB) devices. Having stable radiation patterns and constant gain within the UWB spectrum are significant characteristics of this antenna. The time domain studies on the designed antenna indicate reduced ringing effect for impulse excitation across the band of interest.

  20. UCom: Ultra-wideband Communications in Harsh Propagation Environments

    SciTech Connect

    Nekoogar, F

    2007-03-14

    LLNL has developed an ultra-wideband (UWB) system that provides unique, through-the-wall wireless communications in heavy metallic and heavy concrete indoor channels. LLNL's UWB system is the only available wireless communications system that performs successfully and reliably in facilities where conventional narrowband communications usually fail due to destructive reflections from multiple surfaces. These environments include: cargo ships and reinforced, heavy concrete buildings. LLNL's revolutionary system has applications for the military, as well as commercial indoor communications in multistory buildings, and cluttered industrial structures.

  1. Ultra-Wideband Fast Acquisition System for Positioning in an Underground Mining Environment

    Microsoft Academic Search

    Yassine Salih Alj; Charles L. Despins; Sofiène Affes

    2008-01-01

    A major application of wireless communications in confined indoor areas is positioning. Ultra-wideband (UWB) has been recently promoted as a very promising physical support for such use. However, fast and accurate timing acquisition of the ultra-short pulses transmitted in indoor environments is significantly challenging, and even more so in hostile areas such as underground mines. This paper presents an UWB

  2. TO APPEAR IN IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS (SPECIAL ISSUE ON ULTRA WIDEBAND WIRELESS COMMUNICATIONS) 1 Secure Localization and Authentication in

    E-print Network

    Wu, Dapeng Oliver

    .S. Office of Naval Research under Young Investigator Award N000140210464, and the US National ScienceTO APPEAR IN IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS (SPECIAL ISSUE ON ULTRA WIDEBAND limit the paper scope to range-based approaches and leave the investigation on range-free ones

  3. Slot antenna for ultra-wideband applications

    Microsoft Academic Search

    H. M. Jafari; M. J. Deen; S. Hranilovic; N. K. Nikolova

    2006-01-01

    An ultra-wideband (UWB) antenna is designed for communications applications. Parameters that affect the antenna performance are investigated using both simulations and measurements. The same antenna is redesigned for use in a UWB cancer detection system, and its performance characteristics are investigated in a lossy biological coupling medium

  4. Rapid acquisition for ultra-wideband localizers

    Microsoft Academic Search

    Robert Fleniing; Cherie Kushner; Gary Roberts; Uday Nandiwada

    2002-01-01

    Ultra-wideband (UWB) signals as implemented in our localizers provide a foundation for highly accurate methods of 3D position determination using precise ranging between any two nodes. In a large, distributed network of nodes, the time required for all nodes to acquire each other is of paramount importance. We have developed a method of rapid acquisition that allows two nodes to

  5. An ultra wideband TAG circuit transceiver architecture

    Microsoft Academic Search

    Lucian Stoica; Sakari Tiuraniemi; A. Rabbachin; I. Oppermann

    2004-01-01

    The paper presents the architecture of a low power, low complexity ultra wideband (UWB) transceiver circuit. The circuit is designed for low data rate, low cost applications with built in location and tracking. The system is based on a non-coherent architecture which enables the receiver to be extremely simple and largely insensitive to the transmitted pulse shape. The circuit presented

  6. OPTIMIZED ULTRA-WIDEBAND RADIATION OF DIPOLE ANTENNAS WITH TRIANGLE

    E-print Network

    Southern California, University of

    OPTIMIZED ULTRA-WIDEBAND RADIATION OF DIPOLE ANTENNAS WITH TRIANGLE DRIVING PULSES Anatoliy O Communication Commission (FCC) regulations on spectrum usage. Recent needs and advances in ultra-wideband (UWB. PROBLEM FORMULATION It is accepted1, 2, 3 that conventional wideband antennas like dipoles often do

  7. A generalized time domain multipath channel and its application in ultra-wideband (UWB) wireless optimal receiver design-Part II: physics-based system analysis

    Microsoft Academic Search

    Robert C. Qiu

    2004-01-01

    This paper has established a new theoretical framework that allows us to analyze the ultra-wideband system performance using the closed form formulations. A new generalized time-domain multipath channel based on the geometric theory of diffraction\\/uniform theory of diffraction (GTD\\/UTD) framework is incorporated into the system bit-error rate and signal-to-noise ratio by modifying the existing system model. Closed form expressions for

  8. An empirical study of electromagnetic interference caused by ultra wideband transmissions in an IEEE 802.11a wireless local area network

    Microsoft Academic Search

    R. A. Raines; M. A. Temple; R. O. Baldwin

    2004-01-01

    Military communications require the rapid deployment of mobile high-bandwidth systems. This work characterizes the electromagnetic interference (EMI) effects of ultra wideband (UWB) transmissions on an IEEE 802.11a ad-hoc network throughput performance. Radiated measurements in an anechoic chamber investigate interference performance for three binary modulation schemes including bi-phase shift keying (BPSK), pulse position modulation (PPM), and on-off keying (OOK) and four

  9. Digital ADCs and ultra-wideband RF circuits for energy constrained wireless applications by Denis Clarke Daly.

    E-print Network

    Daly, Denis Clarke

    2009-01-01

    Ongoing advances in semiconductor technology have enabled a multitude of portable, low power devices like cellular phones and wireless sensors. Most recently, as transistor device geometries reach the nanometer scale, ...

  10. Channel estimation for ultra-wideband communications

    Microsoft Academic Search

    Vincenzo Lottici; A. D'Andrea; U. Mengali

    2002-01-01

    This paper deals with channel estimation in ultra-wideband communications operating in a multipath environment and in the presence of multiaccess interference. The channel parameters are the attenuations and delays incurred by the signal echoes along the propagation paths. Time-hopping modulation with binary symbols is assumed. The estimation method is based on the maximum-likelihood criterion and is applied to two different

  11. Ultra-wideband precision asset location system

    Microsoft Academic Search

    Robert J. Fontana; Steven J. Gunderson

    2002-01-01

    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

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

    E-print Network

    Ren, Yu-Jiun

    2009-05-15

    In the future, space solar power transmission and wireless power transmission will play an important role in gathering clean and infinite energy from space. The rectenna, i.e., a rectifying circuit combined with an antenna, is one of the most...

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

    E-print Network

    Ren, Yu-Jiun

    2009-05-15

    In the future, space solar power transmission and wireless power transmission will play an important role in gathering clean and infinite energy from space. The rectenna, i.e., a rectifying circuit combined with an antenna, is one of the most...

  14. Directional Ultra-Wideband Antennas in Planar Technologies

    E-print Network

    Bornemann, Jens

    UWB antennas for specific applications such as radar systems [8]-[9]. The recent work on a directionalDirectional Ultra-Wideband Antennas in Planar Technologies Marjan Mokhtaari and Jens Bornemann Abstract -- Directional ultra-wideband antennas in various planar technologies are described. All designs

  15. Multiple Antenna Time Reversal Transmission In Ultra-Wideband Communications

    E-print Network

    Moura, José

    Multiple Antenna Time Reversal Transmission In Ultra-Wideband Communications Yuanwei Jin, Yi Jiang Abstract-- In this paper we study the multiple antenna time reversal downlink transmission in an ultra-wideband antennas and the user has a single antenna. We design the UWB beamformer that focuses on the intended user

  16. Printed-Circuit Antennas for Ultra-Wideband Monitoring Applications

    E-print Network

    Bornemann, Jens

    Printed-Circuit Antennas for Ultra-Wideband Monitoring Applications Marjan Mokhtaari and Jens (UWB) monitoring applications are introduced. Both microstrip and coplanar waveguide antennas operate, BC, V8W 3P6, Canada j.bornemann@ieee.org Abstract -- Two new printed-circuit antennas for ultra-wideband

  17. Ultra-Wideband Imaging Systems for Breast Cancer Detection

    E-print Network

    Genov, Roman

    Ultra-Wideband Imaging Systems for Breast Cancer Detection Hossein Kassiri Bidhendi, Hamed Mazhab system design and its advantages for breast cancer detection after reading this chapter. Keywords Breast cancer detection · Breast imaging · Ultra-wideband imaging · UWB transceiver · UWB pulses · UWB

  18. Short-Range Ultra-Wideband Systems UMass Antenna Lab USC UltRa Lab UC Berkeley BWRC

    E-print Network

    Southern California, University of

    Short-Range Ultra-Wideband Systems UMass Antenna Lab USC UltRa Lab UC Berkeley BWRC MURI Review: Lunch Break #12;Short-Range Ultra-Wideband Systems UMass Antenna Lab USC UltRa Lab UC Berkeley BWRC;Short-Range Ultra-Wideband Systems UMass Antenna Lab USC UltRa Lab UC Berkeley BWRC UMass UWB Link

  19. Ultra-wideband radar motion sensor

    DOEpatents

    McEwan, T.E.

    1994-11-01

    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.

  20. Ultra-wideband radar motion sensor

    DOEpatents

    McEwan, Thomas E. (Livermore, CA)

    1994-01-01

    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.

  1. Short-Range Ultra-Wideband Systems UMass Antenna Lab USC UltRa Lab UC Berkeley BWRC

    E-print Network

    Southern California, University of

    Short-Range Ultra-Wideband Systems UMass Antenna Lab USC UltRa Lab UC Berkeley BWRC UWB MURI Research ShortShort--Range UltraRange Ultra--Wideband SystemsWideband Systems R. A.R. A. Scholtz (D.(D. GoeckelGoeckel, D., D. PozarPozar, D., D. SchaubertSchaubert)) #12;Short-Range Ultra

  2. Short-Range Ultra-Wideband Systems UMass Antenna Lab USC UltRa Lab UC Berkeley BWRC

    E-print Network

    Southern California, University of

    Short-Range Ultra-Wideband Systems UMass Antenna Lab USC UltRa Lab UC Berkeley BWRC 1:15 PM) #12;Short-Range Ultra-Wideband Systems UMass Antenna Lab USC UltRa Lab UC Berkeley BWRC Long Range-time emulation and CMOS implementation. The UWB MURI Team #12;Short-Range Ultra-Wideband Systems UMass Antenna

  3. Ultra-wideband wireless systems

    Microsoft Academic Search

    G. R. Aiello; G. D. Rogerson

    2003-01-01

    The recent FCC frequency allocation for UWB has generated a lot of interest in UWB technologies. There is 7,500 MHz of spectrum for unlicensed use. The main limitations are provided by the low-power spectral density and by the fact that the transmit signal must occupy at least 500 MHz at whole times. IEEE 802.15.3a is being developed for high-bit-rate PAN

  4. Recent advances in ultra-wideband Raman amplifiers

    Microsoft Academic Search

    S. Namiki; Y. Emori

    2000-01-01

    This talk will review fundamentals of ultra-wideband Raman amplifiers, recent progress of high power pump lasers, and system applications of Raman amplifiers. Pump wavelength determines the gain spectrum of a Raman amplifier. This implies that the gain created by a multi wavelength pumping can have a wideband gain profile, which is approximately described by a linear superposition of each gain

  5. PERFORMANCE EVALUATION OF IMPULSE RADIO ULTRA WIDE BAND WIRELESS SENSOR Lecointre1, 2

    E-print Network

    Boyer, Edmond

    900847 1 of 7 PERFORMANCE EVALUATION OF IMPULSE RADIO ULTRA WIDE BAND WIRELESS SENSOR NETWORKS of Wireless Sensor Networks (WSN) based on Impulse Radio Ultra Wideband (IR-UWB) over a new simulation-UWB PHYsical (PHY) and Medium Access Control (MAC) layer. Pulse collision is modeled according to the used time

  6. Ultra compact filters for ultra-wideband (UWB) applications using multilayer ring resonators

    Microsoft Academic Search

    SeyyedKamal Hashemi; Dariush Mirshekar-Syahkal

    2009-01-01

    Novel compact ultra-wideband (UWB) bandpass filters are proposed. It is based on multilayer ring resonators (MRR). The ring is applied to any loop shape. The filter has a simple structure for fabrication and the design technique can be adapted in order to realize both narrowband and ultra-wideband filters. With the MRR, filters of bandwidths in excess of 10 GHz while

  7. Non-data aided timing acquisition of ultra-wideband transmissions using cyclostationarity

    Microsoft Academic Search

    Liuqing Yang; Zhi Tian; Georgios B. Giannakis

    2003-01-01

    Low-complexity rapid timing acquisition constitutes a major challenge in realizing the high potential that ultra-wideband (UWB) wireless technology promises for indoor communications. We derive and test two such timing acquisition algorithms which capitalize on the cyclostationarity that is naturally present in UWB transmissions. Our novel schemes are blind, they do not require multiple antennas or oversampling, and rely on frame-rate

  8. Performance Analysis of Time-Hopping Pulse Width Modulation for Ultra-Wideband Impulse Radio

    Microsoft Academic Search

    Feng Wang; Chengqi Xu; Xuande Ji; Yan Zhang

    2008-01-01

    The ultra wide-band (UWB) technology is going to become one of main technologies in short-range high-rate wireless communications due to its unique characteristics. This paper presents a new modulation scheme-pulse width modulation (PWM) for UWB communication systems and describes the signal model modulated by this modulation scheme based on the time-hopping (TH) multiple access mode. Its bit error rate (BER)

  9. Ultra-Wideband Direct Conversion Receivers for Satellite On-Board Processing

    E-print Network

    Göckler, Heinz G.

    1 Ultra-Wideband Direct Conversion Receivers for Satellite On-Board Processing ­ System Analysis- tigation of performance degradation in conjunction with the processing of ultra-wideband frequency division, a typical error scenario taken from an ultra-wideband application in satellite communica- tions has been

  10. Design of diversity antenna for ultra-wideband applications

    Microsoft Academic Search

    Feng Zhou; Zuping Qian; Tingting Liu; Jiwei Han; Chuan Peng

    2010-01-01

    A printed ultra-wideband (UWB) antenna operating at the frequency range of 2.9-11.0 GHz is proposed for diversity applications. By adopting two symmetrical P-shaped radiators, the antenna presents wideband impedance matching characteristic. The antenna can achieve good impedance matching and improved isolation by notching a slot at the upper centre portion of the ground plane and inserting a stub in the

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

    SciTech Connect

    Nekoogar, F; Dowla, F

    2009-10-19

    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.

  12. Small, planar, ultra-wideband antennas with top-loading

    Microsoft Academic Search

    Taeyoung Yang; W. A. Davis; W. L. Stutzman

    2005-01-01

    A new top-loaded ultra-wideband antenna covering the 2.4-10.6 GHz impedance bandwidth (VSWR<2.5) and the 2.05-11.6 GHz UWB bandwidth with nearly constant radiated power was introduced. The proposed antenna is a good candidate for backward compatibility of IEEE 802.11g in the 2.4 GHz ISM band, as well as providing an indoor\\/outdoor ultra-wideband frequency range of 3.1-10.6 GHz. In addition, it can

  13. Short-Range Ultra-Wideband Systems UMass Antenna Lab USC UltRa Lab UC Berkeley BWRC

    E-print Network

    Southern California, University of

    for UWB systems #12;Short-Range Ultra-Wideband Systems UMass Antenna Lab USC UltRa Lab UC Berkeley BWRCShort-Range Ultra-Wideband Systems UMass Antenna Lab USC UltRa Lab UC Berkeley BWRC · Some recent results of relevance to UWB theory and practice · Some UWB antenna problems that are outstanding · Future

  14. Optimal pilot waveform assisted modulation for ultra-wideband communications

    Microsoft Academic Search

    Liuqunig Yang; Georgios B. Giannakis

    2002-01-01

    Performance of ultra-wideband (UWB) communication systems can be enhanced by collecting multipath diversity gains, once the channels are acquired at the receiver. In this paper, we develop a novel pilot waveform assisted modulation (PWAM) scheme that is tailored for power-limited UWB communications, and can be implemented in analog form. The PWAM parameters are designed to jointly optimize performance and information

  15. A Circular Wire Antenna for Ultra Wideband Applications

    Microsoft Academic Search

    Z. Zhang; J. T. Bernhard

    2007-01-01

    A novel circular wire antenna suitable for ultra wideband (UWB) applications is presented in this paper. It consists of a circularly curved wire over a ground plane. The wire structure is designed to deliver approximately the same benefits as a circular disc antenna. Effective length is introduced to analyze the operation of the antenna. Experimental results of the antenna have

  16. A Compact Monopole UWB Antenna for Ultra Wideband Applications

    Microsoft Academic Search

    Akkala Subbarao; S. Raghavan

    2009-01-01

    A novel compact Ultra wideband antenna fed by CPW is presented. The antenna has a size of 29 mm ?? 32 mm. It provides band width ranging from 2.9 GHz to 11.1 GHz. The antenna can be easily integrated with radio frequency circuit for low cost. Details of antenna are presented with parametric study. The bandwidth is varied by varying

  17. A small couple slotted antenna for ultra wideband application

    Microsoft Academic Search

    Yusnita Rahayu; T. A. Rahman; R. Ngah; P. S. Hall

    2009-01-01

    The demand for ultra wideband (UWB) communications is rapidly increasing due to the need to support more users and to provide more information with higher data rates. With appropriate technical standards, UWB devices can operate using spectrum occupied by existing radio services without causing interference, thereby permitting scarce spectrum resources to be used more efficiently. This paper presents a small

  18. Shorted biconical antenna for ultra-wideband applications

    Microsoft Academic Search

    J. D. Morrow

    2003-01-01

    This paper presents a simple low-gain omnidirectional ultra-wideband (UWB) antenna. The VSWR is 2:1 or better over the FCC-specified UWB operating band of 3.1 GHz to 10.6 GHz, and the total combined omnidirectionality is better than 12 dB.

  19. Research of circular disc ultra wideband EMC measuring antenna

    Microsoft Academic Search

    Jinghui Qiu; Lingling Zhong; Bo Sun; Zhang Ning

    2008-01-01

    Electromagnetic compatibility (EMC) measuring antenna can be used for EMC radiation disturbed and noise immunity test. Its bandwidth requirement is relatively high, and the antenna needs to cover a wide frequency range. In this paper, the conventional circular disc ultra wideband antenna was expanding researched, and a new method to increase the high frequency of the circular disc antenna was

  20. Multistatic radar with ultra-wideband pulses: FDTD simulation

    Microsoft Academic Search

    F. C. B. F. Muller; R. G. Farias; C. Ld. S. S. Sobrinho; V. Dmitriev

    2005-01-01

    A simulation of a multistatic radar using the finite-difference time-domain method is performed to identify the presence of an intruder inside a residence. The radar operates with ultra-wideband pulses to obtain high resolution. One transmitter and three receivers, positioned outside the residence, are used to estimate the location of an intruder inside the residence without ambiguity.

  1. The Marx generator as an ultra wideband source

    Microsoft Academic Search

    J. R. Mayes; W. J. Carey; W. C. Nunnally; L. Altgilbers

    2001-01-01

    Summary form only given. Traditional uses of the Marx generator have been limited to energy storage and delivery systems, such as charging capacitors or pulse forming lines. However, low energy, high peak power Marx generators are finding applications in Ultra Wideband radar and high power microwave systems. This paper presents the results of a new compact, high powered Marx generator

  2. The Marx generator as an ultra wideband source

    Microsoft Academic Search

    J. R. Mayes; W. J. Carey; W. C. Nunnally; L. Altgilbers

    2001-01-01

    Traditional uses of the Marx generator have been limited to energy storage and delivery systems, such as charging capacitors or pulse forming lines. However, low energy, high peak power Marx generators are finding applications in ultra wideband radar and high power microwave systems. This paper discusses the compact generator as well as an assortment of impulse antennas. Experimental results, including

  3. Ultra wideband multiple-input multiple-output radar

    Microsoft Academic Search

    Hammad A. Khan; Wasim Q. Malik; David J. Edwards; Christopher J. Stevens

    2005-01-01

    The utilization of ultra wideband (UWB) signals enables the radar designer to solve the most important problems of radar target observation. The extremely wide bandwidth enables greater information to be obtained due to high time resolution and the frequency dependence of the scattering centers over this large bandwidth. Increase in the radar's signal bandwidth can improve radar performance by providing

  4. A novel ultra-wideband pulse design algorithm

    Microsoft Academic Search

    Brent Parr; ByungLok Cho; K. Wallace; Zhi Ding

    2003-01-01

    We present a new algorithm to numerically generate pulses that not only have a short time duration for multiple access, but also meet the power spectral constraint of Federal Communications Commission (FCC) ultra-wideband (UWB) mask. In fact, applying our algorithm to the FCC spectral mask for UWB systems can lead to the design of multiple orthogonal pulses that are compliant.

  5. Evaluation of an Ultra-Wideband Propagation Channel

    Microsoft Academic Search

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

    2002-01-01

    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,

  6. A differential detector for an ultra-wideband communications system

    Microsoft Academic Search

    Minnie Ho; V. Srinivasa Somayazulu; Jefsey Foerster; Sumit Roy

    2002-01-01

    Systems using ultra-wideband (UWB) technology have been shown to achieve very high data rates (100 Mbps and above) for short-range, indoor applications. UWB signals exhibit a number of performance advantages in terms of multipath resolution and fading reduction. However, UWB systems can also exhibit significant implementation complexity in timing, synchronization, and signal correlation. This paper presents a differential detector that

  7. Frequency domain detectors for ultra-wideband indoor communications

    Microsoft Academic Search

    Simone Morosi; Tiziano Bianchi

    2006-01-01

    In this paper we propose an innovative communication scheme for ultra-wideband systems which are based on impulse radio. The proposed system relies on both the introduction of the cyclic prefix at the transmitter and the use of a frequency domain detector at the receiver. Two different detection strategies based either on the zero forcing (ZF) or the minimum mean square

  8. Recent Progress in Ultra-Wideband Microwave Breast Cancer Detection

    E-print Network

    Coates, Mark

    Recent Progress in Ultra-Wideband Microwave Breast Cancer Detection Simone A. Winkler, Emily Porter in the field of breast cancer detection research carried out at McGill University. A low-cost time performance. Latest results are shown and presented in comparison to prior experiments. Keywords-breast cancer

  9. Coplanar Printed-Circuit Antenna With Band-Rejection Elements For Ultra-Wideband Filtenna Applications

    E-print Network

    Bornemann, Jens

    Coplanar Printed-Circuit Antenna With Band-Rejection Elements For Ultra-Wideband Filtenna Introduction Filtennas consist of wideband antenna structures, which incorporate narrowband filter elements for band selection or interference reduction [1]. Especially with respect to ultra-wideband (UWB

  10. Imaging of Ultra-Wideband Georadar Data

    NASA Astrophysics Data System (ADS)

    ferguson, Robert; Yedlin, Matthew; Pichot, Christian; Dauvignac, Jean-Yves; Fortino, Nicolas; Gaffet, Stéphane

    2013-04-01

    We present a methodology for georadar acquisition and processing that returns superior images of the subsurface for low cost. Georadar data were acquired in March 2011 in the anti-blast tunnel within the Inter-Disciplinary Underground Science & Technology Laboratory at the Laboratoire Souterrain a Bas Bruit (LSBB, http://lsbb.oca.eu), Rustrel, France. The georadar data from LSBB were acquired with an exponentially tapered slot antenna (ETSA) of the Vivaldi type. The ETSA is connected to an Agilent vector network analyzer and it operates between 150 MHz to 2 GHz with a noise floor of -120 dB. One of the most interesting technical aspects of the recordings is the use of both a conventional bistatic recording geometry (the source / receiver offset is about 65 cm) and what we will call a monostatic recording geometry where the emitting antenna is also the receiving antenna. The monostatic (reflection) data and bistatic (transmission) data are recorded complex numbers and each recorded number is a stack of monochromatic wave measurements. This system is reported to have a number of outstanding attributes including long depth of resolution due to it's wide bandwidth. Compared to other systems it has a greater dynamic range plus low distortion, and this is achieved with low-noise, low-loss cables and shielding with ultra-wideband absorbers. The resulting monostatic georadargrams are a true, zero-offset recording geometry, and so zero-offset migration (imaging that is based on the exploding reflector concept) returns a high accuracy image for low cost. To restore reflection attenuation due to the low Q factor associated with georadar, we apply nonstationary, Gabor-domain deconvolution. We find that amplitude attenuation is restored and phase distortion is corrected. The improved accuracy of our methodology is established first through direct comparison of our Gabor-deconvolved data with conventional, stationary deconvolution where we find that the nonstationary result is superior. Then, using a bistatic data set for an imaging comparison, we show that ZOM ( Zero-Offset Migration) applied to the bistatic data introduces spurious reflection imagery in the upper 50 cm, but that PSDM (Pre-Stack Depth Migration) of the bistatic data returns an image that is similar to ZOM of the monostatic data. The bistatic data were acquired coincident with the monostatic acquisition and have a source / receiver offset of 65 cm. Thus, imaging accuracy associated with PSDM is achieved using ZOM at 1/100 the computational cost. In the deeper section of our dataset, we find that the ZOM image using the monostatic data returns a significantly improved image than PSDM of the bistatic data. This is unexpected, but perhaps the difference is a phenomenon that is due to out-of-plane reflections and that 2D PSDM is rightly defocussing out-of-plane energy. We feel that subsequent 3D data acquisition could resolve this difference.

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

    PubMed

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

    2014-01-01

    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

  12. An Agile, Ultra-Wideband Pulse Radio Transceiver With Discrete-Time Wideband-IF

    Microsoft Academic Search

    Frank Zhang; Anuranjan Jha; Ranjit Gharpurey; Peter Kinget

    2009-01-01

    A pulse-based CMOS ultra-wideband transmitter and receiver have been realized using a standard digital 90 nm CMOS process. The transceiver uses digital templates stored in high-speed memories for pulse generation on the transmit side and for correlation on the receive side. This allows fast band switching for multi-band operation and interferer avoidance without the requirement for fast-settling phase-locked loops. The

  13. Practical Demonstration of Filterbank Receiver for Ultra-Wideband Radios

    Microsoft Academic Search

    Antonio Mollfulleda; Christian Ibars; Joan Anton Leyva; Lluis Berenguer

    2006-01-01

    In this paper we show that a filterbank receiver architecture for ultra-wideband impulse radio systems is adequate in dense multi-path channels. This approach is derived from a time-frequency representation of the received signal by means of the short time Fourier transform. The receiver consists of an analog section containing bandpass filters followed by a bank of analog-to-digital converters (ADC), while

  14. Design Considerations for Low-Power Ultra Wideband Receivers

    Microsoft Academic Search

    Payam Heydari

    2005-01-01

    This paper studies design considerations for low-power ultra wideband (UWB) receiver architectures. First, three different architectures for the impulse-radio UWB transceiver are studied, while investigating the power-performance trade-offs. As is elaborated in the paper, a more power-efficient architecture should undertake part of the signal processing in the analog-domain. Next, the multiband UWB transceiver is studied and power-efficient circuits for the

  15. COMPACT MICROSTRIP-FED ANTENNA FOR ULTRA-WIDEBAND APPLICATIONS

    Microsoft Academic Search

    Xin Zhang; Yu-Yin Xia; Jie Chen; Wen-Tao Li

    2009-01-01

    Abstract—A novel printed monopole,antenna for ultra-wideband (UWB) applications is presented, which is composed of wide slot and Y-shaped microstrip feed line with a pair of inverted-L-shaped notches. The prototype with an overall size of 26 mm,× 30 mm,× 2 mm,achieves good impedance matching, constant gain, stable radiation patterns, and a relative impedance bandwidth of 110.6% is achieved, which covers 3.09–10.74

  16. Printed diversity antenna for Ultra-wideband applications

    Microsoft Academic Search

    Yong Cheng; Wen-jun Lu; Chong-hu Cheng

    2010-01-01

    A printed diversity antenna for Ultra-wideband applications is proposed. The proposed antenna is composed of two elliptical shape monopoles. Two stubs and a slot are introduced to reduce the mutual coupling between the two elements. The antenna has been investigated numerically and experimentally. As the results show that the operation bandwidth of the antenna is from 3.1GHz to 10.6GHz and

  17. A new quasi - isotropic antenna for ultra - wideband application

    Microsoft Academic Search

    E. S. Pires; G. Fontgalland; M. A. B. de Melo; R. M. Valle; G. F. Aragao; T. P. Vuong

    2007-01-01

    In this paper, we propose a new compact antenna design for applications where an ultra-wideband (UWB) frequency range is needed. The main features of the proposed antenna is the capability of generate a quasi-isotropic radiation pattern. For this case, the proposed antenna is designed to operate from 2.17 GHz to 2.68 GHz. The construction details of the conceived antenna are

  18. Joint Time-Frequency Analysis of Ultra Wideband Radar Signals

    Microsoft Academic Search

    Hoi-Shun Lui; Nicholas V. Z. Shuley

    The time variant nature of an Ultra-Wideband (UWB) radar signal scattered from a radar target is well described throughout the literature. To study the behaviour of these transient signals, Joint Time-Frequency (TF) analysis is considered. Various Time-Frequency Distributions (TFDs) have been developed in the signal processing area over the last twenty years but little work has been done in a

  19. Planar elliptical element ultra-wideband dipole antennas

    Microsoft Academic Search

    H. G. Schantz

    2002-01-01

    Abstract: This note introduces a new class of ,planar ultra-wideband (UWB) dipoles that use elliptical elements. These ,antennas offer good ,dipole performance ,over nearly two octaves in frequency. Unlike ,more traditional broadband dipole elements that must be around a quarter-wavelength to radiate efficiently, planar elliptical UWB dipoles still exhibit a –10 dB return loss for a 0.20? element size, and

  20. A novel auto-reference ultra-wideband receiver scheme

    Microsoft Academic Search

    Xuewen Liao; Shihua Zhu; Erlin Zeng

    2007-01-01

    A new auto-reference (AR) transmit-receive scheme and a corresponding group decision algorithm on the generalized likelihood\\u000a ratio testing (GLRT) principle is proposed in this paper to overcome the drawbacks of the power inefficiency and the high\\u000a noise vulnerability in transmitted-reference (TR) ultra-wideband (UWB) systems. A partly overlapped detection window structure\\u000a is introduced in which the decided data frames are regarded

  1. Iterative Synchronization of Multiuser Ultra-Wideband Signals

    Microsoft Academic Search

    Ersen Ekrem; Mutlu Koca; Hakan Deliç

    2010-01-01

    In this paper, two novel iterative chip-level synchronization methods, one blind and the other data-aided, are proposed for chip-interleaved time-hopping (TH) ultra-wideband signals that are subject to intersymbol interference (ISI) and multiple access interference (MAI). Both algorithms are soft-input, soft-output devices which receive the a posteriori probability of each chip from the minimum mean-square error (MMSE) filter that suppresses both

  2. arXiv:cs.IT/0603018v13Mar2006 On Non-coherent MIMO Channels in the Wideband

    E-print Network

    Zheng, Lizhong

    access (W-CDMA) and Ultra- wideband (UWB) radio. Motivated by the ever increasing demand for higher wideband wireless data rates, we consider multiple antenna communication over the wideband wireless channel of single antenna wideband channels dates back to 1969 and early work has considered the Rayleigh fading

  3. Ultra-Wideband Printed-Circuit Array Antenna for Medical Monitoring Applications

    E-print Network

    Bornemann, Jens

    Ultra-Wideband Printed-Circuit Array Antenna for Medical Monitoring Applications Hung-Jui (Harry measurements. Keywords ­ Printed-circuit antennas, ultra-wideband antennas, (UWB), antenna array, coplanar) technology, the UWB antenna is one of the most essential components for a UWB system. Many applications

  4. Design of Compact Dual-Polarized Printed-Circuit Antenna for Ultra-Wideband Applications

    E-print Network

    Bornemann, Jens

    Design of Compact Dual-Polarized Printed-Circuit Antenna for Ultra-Wideband Applications K. Rambabu a small printed-circuit antenna, which is well suited for ultra-wideband and dual- polarized applications for short-range and high bandwidth applications, e.g. [1]. UWB antenna performance can be achieved

  5. Design of an Ultra-Wideband Antenna Using Taguchi's Optimization Method Wei-Chung Weng 1

    E-print Network

    Elsherbeni, Atef Z.

    , and UWB antennas. 1. Introduction In 2002, the Federal Communications Commission (FCC) released the ultra-widebandDesign of an Ultra-Wideband Antenna Using Taguchi's Optimization Method Wei-Chung Weng 1 , Fan Yang (UWB) antenna, where Taguchi's method is applied as an external optimizer to drive IE3D and optimize

  6. A compact tapered-slot-feed annular slot antenna for ultra-wideband applications

    Microsoft Academic Search

    Tzyh-Ghuang Ma; Shyh-Kang Jeng

    2004-01-01

    A novel compact tapered-slot-fed annular slot antenna suitable for ultra-wideband (UWB) applications is presented. Frequency domain as well as time domain characteristics of the antenna are well investigated and discussed. A measure to quantify the performance of the radiation patterns of such an ultra-wideband antenna is described.

  7. A tapered-slot-feed loop antenna for ultra-wideband applications

    Microsoft Academic Search

    Tzyh-Ghuang Ma; Shyh-Kang Jeng

    2004-01-01

    A novel tapered-slot-fed loop antenna suitable for ultra-wideband (UWB) applications is presented. Frequency domain characteristics of the antenna are well investigated and a measure to quantify the radiation patterns of such an ultra-wideband antenna is described. Time domain behaviors of the proposed antenna are derived and discussed as well.

  8. Spotforming with an array of ultra-wideband radio transmitters

    SciTech Connect

    Dowla, F; Spiridon, A

    2004-02-05

    Ultra-wideband (UWB) array signal processing has the distinct advantage in that it is possible to illuminate or focus on ''spots'' at distant points in space, as opposed to just illuminating or steering at certain directions for narrowband array processing. The term ''spotforming'' is used to emphasize the property that point-focusing techniques with UWB waveforms can be viewed as a generalization of the well-known narrowband beamforming techniques. Because methods in spotforming can lead to powerful applications for UWB systems, in this paper we derive, simulate and experimentally verify UWB spot size as a function of frequency, bandwidth and array aperture.

  9. An Overview of the Recent Wideband Transcutaneous Wireless Communication Techniques

    PubMed Central

    Ghovanloo, Maysam

    2013-01-01

    Neuroprosthetic devices such as cochlear and retinal implants need to deliver a large volume of data from external sensors into the body, while invasive brain-computer interfaces need to deliver sizeable amounts of data from the central nervous system to target devices outside of the body. Nonetheless, the skin should remain intact. This paper reviews some of the latest techniques to establish wideband wireless communication links across the skin. PMID:22255673

  10. Optically addressed ultra-wideband phased antenna array

    NASA Astrophysics Data System (ADS)

    Bai, Jian

    Demands for high data rate and multifunctional apertures from both civilian and military users have motivated development of ultra-wideband (UWB) electrically steered phased arrays. Meanwhile, the need for large contiguous frequency is pushing operation of radio systems into the millimeter-wave (mm-wave) range. Therefore, modern radio systems require UWB performance from VHF to mm-wave. However, traditional electronic systems suffer many challenges that make achieving these requirements difficult. Several examples includes: voltage controlled oscillators (VCO) cannot provide a tunable range of several octaves, distribution of wideband local oscillator signals undergo high loss and dispersion through RF transmission lines, and antennas have very limited bandwidth or bulky sizes. Recently, RF photonics technology has drawn considerable attention because of its advantages over traditional systems, with the capability of offering extreme power efficiency, information capacity, frequency agility, and spatial beam diversity. A hybrid RF photonic communication system utilizing optical links and an RF transducer at the antenna potentially provides ultra-wideband data transmission, i.e., over 100 GHz. A successful implementation of such an optically addressed phased array requires addressing several key challenges. Photonic generation of an RF source with over a seven-octave bandwidth has been demonstrated in the last few years. However, one challenge which still remains is how to convey phased optical signals to downconversion modules and antennas. Therefore, a feed network with phase sweeping capability and low excessive phase noise needs to be developed. Another key challenge is to develop an ultra-wideband array antenna. Modern frontends require antennas to be compact, planar, and low-profile in addition to possessing broad bandwidth, conforming to stringent space, weight, cost, and power constraints. To address these issues, I will study broadband and miniaturization techniques for both single and array antennas. In addition, a prototype transmitting phased array system is developed and shown to demonstrate large bandwidth as well as a beam steering capability. The architecture of this system can be further developed to a large-scale array at higher frequencies such as mm-wave. This solution serves as a candidate for UWB multifunctional frontends.

  11. Small High Performance Ultra Wideband UHF Multipurpose Planar Antenna A. Babar* (1)

    E-print Network

    Elsherbeni, Atef Z.

    Wideband antenna [1], resonating on a wide range of commonly used Ultra High Frequency (UHF) bands. The antenna's bandwidth ranges from 1.22GHz to above 3GHz. The ultra wide bandwidth was achieved by dispersing electronics and other communication devices. The antenna covers most of the ultra high frequency (UHF) band

  12. Robust range-based localization and motion planning under uncertainty using ultra-wideband radio

    E-print Network

    Prentice, Samuel J. (Samuel James)

    2007-01-01

    The work presented in this thesis addresses two problems: accurately localizing a mobile robot using ultra-wideband (UWB) radio signals in GPS-denied environments; and planning robot trajectories that incorporate belief ...

  13. An EnantioMorphic BLumlein ultra-wideband source

    SciTech Connect

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

    1992-09-01

    Working designs exist for 1 GW, 1 kHz ultra-wideband (UWB) sources (e. g. SNIPER). As these generators are pressed to higher peak powers and repetition rates, insulation, energy loss due to stray capacitance, and system efficiency (including power supplies and modulators) become critical issues. The EnantioMorphic (mirror image) BLumlein (EMBL) is a new type of vector inversion transmission line pulser which is designed to alleviate some of these problems. The design goals for EMBL are: 10 GW peak power, 700 kV,{approximately}1 kHz rep-rate and <100 ps risetime in a 50 ohm geometry. A gas spark gap peaking switch adds UWB frequency components to the EMBL output pulse.

  14. An EnantioMorphic BLumlein ultra-wideband source

    SciTech Connect

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

    1992-01-01

    Working designs exist for 1 GW, 1 kHz ultra-wideband (UWB) sources (e. g. SNIPER). As these generators are pressed to higher peak powers and repetition rates, insulation, energy loss due to stray capacitance, and system efficiency (including power supplies and modulators) become critical issues. The EnantioMorphic (mirror image) BLumlein (EMBL) is a new type of vector inversion transmission line pulser which is designed to alleviate some of these problems. The design goals for EMBL are: 10 GW peak power, 700 kV,{approximately}1 kHz rep-rate and <100 ps risetime in a 50 ohm geometry. A gas spark gap peaking switch adds UWB frequency components to the EMBL output pulse.

  15. A differential-fed magneto-electric dipole antenna for ultra-wideband applications

    Microsoft Academic Search

    Mingjian Li; Kwai-Man Luk

    2011-01-01

    an ultra-wideband differential-fed magneto-electric dipole antenna with unidirectional radiation patterns is proposed in this paper. A novel parallel twin-L shaped differential feeding structure provides an ultra-wideband impedance matching. A unified gain can be realized by the modification of the magneto- electric dipole and using a rectangular cavity, instead of a normal ground plane. The antenna can achieve an impedance bandwidth

  16. Compact modified bow-tie slot antenna fed by CPW for ultra-wideband applications

    Microsoft Academic Search

    Chi-Hsuan Lee; Shih-Yuan Chen; Powen Hsu

    2009-01-01

    A coplanar waveguide fed compact modified bow-tie slot antenna is proposed for use in the ultra-wideband systems. The modification is made by attaching a pair of meandered slotlines to the upper ends of the small bow-tie slot. With a proper slotline length, the impedance bandwidth of the proposed antenna can be adjusted to cover the entire ultra-wideband and the antenna

  17. Frequency-diversity coded OFDM for ultra-wideband systems with under-sampling-rate receivers

    Microsoft Academic Search

    Mao-Ching Chiu; Wei-Du Wu; Chi-chao Chao

    2005-01-01

    Orthogonal frequency division multiplexing (OFDM) has been proposed for use as the physical layer of ultra-wideband (UWB) systems for high-rate, short-range personal area networking (PAN). For ultra-wideband systems, there is a constraint on the maximum power spectral density for the transmitted signal. Therefore, the bandwidth of the transmitted spectrum must be spread widely by a bandwidth expansion scheme so that

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

    NASA Astrophysics Data System (ADS)

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

    2013-06-01

    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.

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

    SciTech Connect

    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

    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.

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

    SciTech Connect

    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

    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.

  1. A novel pot shaped CPW-fed slot antenna for Ultra wideband applications

    Microsoft Academic Search

    Akkala. Subbarao; S. Raghavan

    2011-01-01

    A novel compact Ultra wideband antenna fed by CPW is presented. The antenna has a size of 29 mm x 31 mm. The antenna is excited by Pot shaped inner tuning stub. It provides band width ranging from 2.9 GHz to 10.2 GHz which covers Ultra Wide bandwidth. The antenna can be easily integrated with radio frequency circuit for low

  2. An adaptive Orthogonaly Division Multiplexing baseband modem for wideband wireless communication

    E-print Network

    Tan, Jit Ken

    2006-01-01

    This thesis shows the design of an Orthogonal Frequency Division Multiplexing base-band modem with Frequency Adaptive Modulation protocol for a wideband indoor wireless channel. The baseband modem is implemented on a Field ...

  3. Ultra-wideband Propagation Loss Around a Human Body in Various Surrounding Environments

    NASA Astrophysics Data System (ADS)

    Yamamoto, H.; Kobayashi, T.

    Ultra-wideband (UWB) technologies have been anticipated for use in wireless body area networks (WBAN) because of their low power consumption and anti-multipath capabilities. This chapter presents the UWB (3.1-10.6 GHz) propagation loss in WBAN scenarios between on-body antennas in three different surrounding environments. The measurements were performed in a 3-m radio anechoic chamber, a classroom, and a small room. The propagation paths were roughly divided into line-of-sight (LOS) and non-LOS (NLOS) ones. Small rooms, particularly NLOS, yielded higher reception power than larger rooms. This was attributed to the ample multipath from the nearby floor, walls, and ceiling. The UWB maximum propagation losses in three surrounding environments were smaller than ones of CW (6.85 GHz). This is because nulls caused by interference were cancelled out by the ultra-wide bandwidth. The propagation losses of low-band (3.4-4.8 GHz) and high-band (7.25-10.25 GHz) UWB were also evaluated. In WBAN scenarios, the low-band yielded lower propagation loss than the high-band and approximately the same loss as the full-band UWB (3.1-10.6 GHz).

  4. Optimal Waveforms Design for Ultra-Wideband Impulse Radio Sensors

    PubMed Central

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

    2010-01-01

    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

  5. A 4-bit Ultra-Wideband Beamformer with 4ps True Time Delay Resolution Jonathan D. Roderick, Harish Krishnaswamy, Kenneth Newton, and Hossein Hashemi

    E-print Network

    Southern California, University of

    , it fails to mimic the true time delay needed in ultra-wideband (UWB) multi-antenna systems. UWB phased@usc.edu Abstract-- This paper documents an ultra-wideband (UWB) fully integrated beamformer which featuresA 4-bit Ultra-Wideband Beamformer with 4ps True Time Delay Resolution Jonathan D. Roderick, Harish

  6. 890 IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 57, NO. 4, APRIL 2009 Post-Compensation of Ultra-Wideband Antenna

    E-print Network

    Purdue University

    -Compensation of Ultra-Wideband Antenna Dispersion Using Microwave Photonic Phase Filters and Its Applications to UWB experimental post-compensation of ultra-wideband (UWB) antenna dispersion at a receiver front-end by using and communications. Index Terms--Antenna dispersion, microwave photonics, radar resolution, ultra-wideband (UWB

  7. IEEE TRANSACTIONS ON ADVANCED PACKAGING, VOL. 30, NO. 3, AUGUST 2007 533 Design and Fabrication of Ultra-Wideband

    E-print Network

    Pham, Anh-Vu

    thin-films by standard PCB equipments. Variations in the LCP thin-film thickness are characterized), microwave, thin-film, ultra-wideband (UWB). I. INTRODUCTION LIQUID crystal polymer (LCP) is a low of Ultra-Wideband Baluns Embedded in Multilayer Liquid Crystal Polymer Flex Andy C. Chen, Member, IEEE

  8. Ultra-Wideband Optical Modulation Spectrometer (OMS) Development

    NASA Technical Reports Server (NTRS)

    Gardner, Jonathan (Technical Monitor); Tolls, Volker

    2004-01-01

    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.

  9. UltraUltra--Wideband (UWB)Wideband (UWB) Wireless CommunicationsWireless Communications

    E-print Network

    Qiu, Robert Caiming

    - Embedded Apps Telematics / Telemetry Ericsson R380 PDQ Smart Phone Palm RIM Blackberry HP Jornada 720 w/ PC Area Network Local Area Network 3G & UWB Combining Air Interface3G & UWB Combining Air Interface W LA NOpen Research Issues · System and protocol design · Analysis, performance modeling · Test-bed development

  10. Efficient Wideband Electromagnetic Modeling for Indoor Wireless Channels: A High-Order Finite-

    E-print Network

    .toronto.edu Statistical, measurement-based propagation models are widely employed for the analysis of indoor wireless and accuracy that has limited the application of full-wave analysis to indoor channels. Our approachEfficient Wideband Electromagnetic Modeling for Indoor Wireless Channels: A High-Order Finite

  11. Range sidelobe suppression technique for coherent ultra wide-band random noise radar imaging

    Microsoft Academic Search

    Xiaojian Xu; Ram M. Narayanan

    2001-01-01

    When applied in airborne imaging surveillance, ultra wide-band (UWB) random noise radars have their special merits. Because of the randomness and the ultrawide bandwidth of the transmit and receive signals, such radars can be used for covert detection and identification, and are immune from hostile detection and jamming while preserving very high range resolution. However, the images are plagued with

  12. Design Of Ultra Wideband Coplanar Waveguide Fed Rectangular Slot Antenna With Tuning Stub

    E-print Network

    Elsherbeni, Atef Z.

    antenna tuned by a patch stub is designed and presented for ultra wideband band applications. The presented antenna exhibits a small size, a wide bandwidth of 98%, and a 6 dB average gain. Introduction% bandwidth in the X-band for a size of only 12 mm. In this paper, a CPW fed rectangular slot antenna

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

    E-print Network

    Arslan, Hüseyin

    ANTENNA CONCEPTS A wide variety of antennas are suitable for use in ultra- wideband applications. Some, a multi-band or OFDM approach may be more tolerant of dispersive antennas. ABSTRACT This paper presents-dispersive, but also more compact, small element antennas are preferred in many applications. The imminent widespread

  14. AN ABSTRACT OF A THESIS TIME-REVERSED MIMO FOR ULTRA-WIDEBAND

    E-print Network

    Qiu, Robert Caiming

    - reversed systems. Ultra-wideband (UWB) has many merits wich include low-cost design, high data rates antennas in a TiR UWB-MIMO system is investigated. Measurement and simulation experiments are carried out spacing for a TiR UWB- MIMO system with two receive antennas and compares to a TiR UWB-MISO system

  15. Progress In Electromagnetics Research, Vol. 121, 121139, 2011 LOW-PROFILE DIRECTIONAL ULTRA-WIDEBAND AN-

    E-print Network

    Doran, Simon J.

    Abstract--A compact-size planar antenna with ultra-wideband (UWB) bandwidth and directional patterns of the antenna, a new low-profile antenna configuration is proposed. Three types of directional UWB antennas that the proposed antenna features a reflection coefficient below -10 dB over the UWB range from 4.2 GHz to 8.5 GHz

  16. SYNCHRONIZATION OF ULTRA-WIDEBAND SIGNALS IN THE DENSE MULTIPATH CHANNEL

    E-print Network

    Southern California, University of

    Copyright 2004 Eric A. Homier #12;Dedication To my father, Jay, for his constant support and encouragement Demetras for all her help. I would like to thank all of my colleagues at the Ultra-Wideband Radio through this endeavor. Many thanks to my father, Jay Homier, for setting me on the path at an early age

  17. Theoretical study of sensing targets through the wall using ultra-wideband technology

    Microsoft Academic Search

    Xiaoyang Huang; Bingquan Chen; Hong-Liang Cui; Ke Wang; Robert Pastore; Mark Farwell; Wilbur Chin; Jennifer Ross; Moses Mingle

    2005-01-01

    This study investigates the modeling of through-wall sensing using ultra-wideband (UWB) signals. The combined method of ray tracing and diffraction (CMRTD) is employed to model and study the interaction between the UWB signal and the target. The result is obtained in frequency domain, and then transformed into time domain by use of inverse Fourier transform. Numerical results of scattering from

  18. Performance of an Optimally Spaced PPM Ultra-Wideband System with Direct Sequence

    E-print Network

    Liu, Huaping

    1 Performance of an Optimally Spaced PPM Ultra-Wideband System with Direct Sequence Spreading position modulation (PPM) for data modulation and direct sequence (DS) spreading for multiple access spread spectrum systems, the use of spreading codes is solely for accommodating multiple users. Direct

  19. Simulated Transient Radiation Characteristics of Optimized Ultra Wideband Printed Dipole Antennas

    Microsoft Academic Search

    P. Cerny; M. Mazanek

    2007-01-01

    In case of particular ultra wideband applications (i.e. radar, positioning, etc.), it is crucial to know the transient responses of antennas. This paper picks up the threads of the previous work, where the optimization process searches for the dipole shape, which accomplishes two required parameters - good matching and minimal distortion. The particle swarm optimization method was used in the

  20. Experiments for ultra-wideband imaging radar with one-dimentional Synthetic Aperture

    Microsoft Academic Search

    Daeman Kim; Shangyoual Shin

    2011-01-01

    The experiments to acquire the basic data of the ultrawideband radar have been performed. In the experiments, targets are located at the back of the extruded polystyrene foam (Styrofoam) wall, and the antenna is scanned over the Styrofoam wall at the constant distance while the responses are recorded. For the experiments, the ultra-wideband radar consists of an oscilloscope, an impulse

  1. Ultra-wideband antennas for combined magnetic resonance imaging and UWB radar applications

    Microsoft Academic Search

    U. Schwarz; F. Thiel; F. Seifert; R. Stephan; M. Hein

    2009-01-01

    Magnetic resonance imaging (MRI) is one of the most highly appreciated medical diagnostic techniques worldwide. Recent developments aim at adding the capability of creating focused images of moving objects. Among the potential navigator techniques required for such an improved MRI is ultra-wideband (UWB) radar. We have studied the performance of UWB antennas for biomedical imaging inside the 3-Tesla MRI system

  2. Performance of ultra-wideband communications in the presence of interference

    Microsoft Academic Search

    Li Zhao; Alexander M. Haimovich

    2002-01-01

    We analyze the performance of ultra-wideband (UWB) communications in the presence of interference. Closed-form expressions are provided for the jam resistance of UWB with binary pulse position modulation utilizing rectangular pulses. A simple approximation is obtained for the special case of tone interference. The jam resistance analysis is extended to more practical UWB waveforms such as Gaussian and Rayleigh monocycles.

  3. Ultra-wideband radar sensors for short-range vehicular applications

    Microsoft Academic Search

    Ian Gresham; Alan Jenkins; Robert Egri; Channabasappa Eswarappa; Noyan Kinayman; Nitin Jain; Richard Anderson; Frank Kolak; Ratana Wohlert; Shawn P. Bawell; Jacqueline Bennett; Jean-Pierre Lanteri

    2004-01-01

    The recent approval granted by the Federal Communications Commission (FCC) for the use of ultra-wideband signals for vehicular radar applications has provided a gateway for the introduction of these sensors in the commercial arena as early as 2004. However, the rules governing the allowable spectral occupancy create significant constraints on the sensors' operation. This is further complicated by the variety

  4. Optimal and suboptimal receivers for ultra-wideband transmitted reference systems

    Microsoft Academic Search

    Yi-Ling Chao; Robert A. Scholtz

    2003-01-01

    The optimal receiver for an ultra-wideband transmitted reference (UWB TR) system in a single user multipath environment is derived, based on knowledge of channel properties. The performances of this optimal receiver and other crosscorrelation receivers are analyzed and compared. The usual crosscorrelation receiver which is often used in UWB TR systems is shown to be suboptimal. In addition, an UWB

  5. NOVEL COMPACT MICROSTRIP ULTRA-WIDEBAND FILTER UTILIZING SHORT-CIRCUITED STUBS WITH LESS VIAS

    Microsoft Academic Search

    Mohammad Shahrazel Razalli; Alyani Ismail; Mohd Adzir Mahdi; Mohd Nizar Hamidon

    2008-01-01

    We present here a new pattern with compact size of Ultra Wideband (UWB) microwave filter. The filter is based on quarter-wave length short-circuited stubs model. We introduced here a new schematic model by extracting all parasitic elements such as T- junction and discontinuity in our new pattern of UWB filter. This new filter has minimal number of vias and improved

  6. Performance of RAKE Reception for Ultra Wideband Signals in a Lognormal-fading Channel

    Microsoft Academic Search

    J. Zhang; R. A. Kennedy; T. D. Abhayapala

    RAKE reception for Ultra Wideband is crucial as the radiated power is restricted to be very low and there exist many resolvable multipath components. In this paper, the effectiveness of RAKE reception is investigated analytically. First, the conditions under which the interference in the RAKE fingers can be ignored are discussed. Then a method is introduced to derive the explicit

  7. Conditions and Performance of Ideal RAKE Reception for Ultra-Wideband Signals in Lognormal Fading Channels

    Microsoft Academic Search

    Jian Zhang; Rodney A. Kennedy; Thushara D. Abhayapala

    2003-01-01

    In this paper, the conditions and performance of ideal RAKE reception for time hopping Ultra- Wideband (UWB) investigated. Owing to the complex propagation phenomena and specific structure of UWB signals, new problems relevant to the operation of RAKE receivers arise. This motivates us to reconsider the conditions under which a RAKE receiver can work effectively with negligible interference between fingers.

  8. Frequency domain detection for ultra-wideband communications in the indoor environment

    Microsoft Academic Search

    Tiziano Bianchi; Simone Morosi

    2004-01-01

    We propose an innovative communication scheme for ultra-wideband systems which are based on impulse radio technologies. The proposed system relies on both the introduction of the cyclic prefix at the transmitter and the use of a frequency domain detector at the receiver. In particular, two different detection strategies based either on the zero forcing (ZF) or the minimum mean square

  9. Frequency domain detection strategies for short-range ultra-wideband communication systems

    Microsoft Academic Search

    Tiziano Bianchi; Simone Morosi

    2005-01-01

    In this paper, we propose a detection strategy for high rate short-range impulse radio ultra-wideband systems. The proposed detection scheme relies on both the introduction of the cyclic prefix at the transmitter and the use of a frequency domain multiuser detection approach at the receiver. Zero forcing (ZF) and minimum mean square error (MMSE) multiuser detectors have been investigated and

  10. AN ENERGY EFFICIENT SUB-THRESHOLD BASEBAND PROCESSOR ARCHITECTURE FOR PULSED ULTRA-WIDEBAND COMMUNICATIONS

    Microsoft Academic Search

    V. Sze; R. Blazquez; M. Bhardwaj; A. Chandrakasan

    2006-01-01

    This paper describes how parallelism in the digital baseband processor can reduce the energy required to receive ultra- wideband (UWB) packets. The supply voltage of the digital baseband is lowered so that the correlator operates near its minimum energy point resulting in a 68% energy reduction across the entire baseband. This optimum supply voltage occurs below the threshold voltage, placing

  11. Frequency domain detectors for ultra-wideband communications in short-range systems

    Microsoft Academic Search

    Simone Morosi; Tiziano Bianchi

    2008-01-01

    In this paper, we propose an original detection scheme for high rate short-range impulse radio ultra-wideband systems. The proposed receiver relies on both the introduction of the cyclic prefix at the transmitter and the use of a frequency domain multiuser detector at the receiver. Zero forcing (ZF) and minimum mean square error (MMSE) detection strategies have been investigated and compared

  12. On the ranging performance in an underground mine using an ultra-wideband fast acquisition system

    Microsoft Academic Search

    Yassine Salih-Alj; Charles Despins; Sofiene Affes

    2009-01-01

    Ultra-wideband (UWB) communication systems provide very high data rates by transmitting extremely short duration pulses. The impulse waveform is one of the key factors that influence the performance of these systems. While fulfilling the FCC spectral emission requirements, the pulse shape must offer high detection capabilities with suitable levels of accuracy. In this paper, various pulse shapes are considered within

  13. On the ranging performance in an underground mine using ultra-wideband fast acquisition system

    Microsoft Academic Search

    Yassine Salih Alj; Charles Despins; Sofiene Affes

    2009-01-01

    Ultra-wideband (UWB) communication systems provide very high data rates by transmitting extremely short duration pulses. The impulse waveform is one of the key factors that influence the performance of these systems. While fulfilling the FCC spectral emission requirements, the pulse shape must offer high detection capabilities with suitable levels of accuracy. In this paper, various pulse shapes are considered within

  14. Frequency domain multiuser detectors for ultra-wideband short-range communications

    Microsoft Academic Search

    Simone Morosi; Tiziano Bianchi

    2005-01-01

    In this paper, we propose an original multiuser detector for high rate short-range impulse radio ultra-wideband systems. The proposed receiver relies on both the introduction of the cyclic prefix at the transmitter and the use of a frequency domain multiuser detector at the receiver. Zero forcing (ZF) and minimum mean square error (MMSE) detection strategies have been investigated and compared

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

    E-print Network

    Kansas, University of

    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

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

    Microsoft Academic Search

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

    2007-01-01

    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

  17. Wideband flexible transmitter and receiver pair for implantable wireless neural recording applications

    Microsoft Academic Search

    Ming Yin; Maysam Ghovanloo

    2007-01-01

    This paper presents a complete wideband 900 MHz wireless link with 75 MHz bandwidth consisting of an integrated flexible transmitter and a custom-designed receiver for wireless multichannel neural recording and biotelemetry applications. The transmitter is basically an LC-tank voltage controlled oscillator (VCO) with multiple tunable parameters. The hybrid tank consists of binary weighed PMOS varactors and a surface-mount (SMD) off-chip

  18. A wideband PWM-FSK receiver for wireless implantable neural recording applications

    Microsoft Academic Search

    Ming Yin; Maysam Ghovanloo

    2008-01-01

    We have custom designed a wideband receiver for wireless implantable neural recording (WINeR) systems that use pulse width modulation and frequency-shift-keying (PWM-FSK) to wirelessly transmit neural signals across a short distance (lm). The receiver consists of a 50 MHz ~ 1 GHz down-converter, FSK & PWM demodulators, and a USB interface. The receiver also digitizes the incoming samples using a

  19. Slot Antennas For Dual And Wideband Operation In Wireless Communication Systems

    E-print Network

    Elsherbeni, Atef Z.

    for dual and wide band operation in wireless systems. One design was realized using a tapered meander slot are computed and presented. Keywords: Wideband, dual band, coplanar patch antennas, meander slot antennas. 1=2.2. Two antennas are designed for each band of the WLANS 2.4-2.48GHz and 5.7-5.85Ghz. Designs 1

  20. A Schottky barrier diode ultra-wideband amplitude modulation (AM) detector in foundry CMOS technology

    Microsoft Academic Search

    Swaminathan Sankaran; Kenneth KO

    2006-01-01

    Utility of Schottky diodes fabricated in foundry digital 130-nm CMOS technology is demonstrated by implementing an ultra-wideband (UWB) amplitude modulation detector consisting of a low noise amplifier (LNA), a Schottky diode rectifier, and a low-pass filter. The detector is matched to 50 Omega, from 0-10.3 GHz and 0-1.7 GHz at the input and output, respectively and almost covers the entire

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

    Microsoft Academic Search

    Yijun Zhou; Michael Yan-Wah Chia

    2008-01-01

    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

  2. A study of low-power ultra wideband radio transceiver architectures

    Microsoft Academic Search

    Payam Heydari

    2005-01-01

    The paper studies low-power ultra wideband (UWB) transceiver architectures. First, three different architectures for the impulse-radio UWB transceiver are studied, while investigating the power-performance tradeoffs. The paper illustrates that a more power-efficient architecture should perform part of the signal processing in the analog-domain. Next, the multiband UWB transceiver is studied and power-efficient circuits for the front-end of the UWB transceiver

  3. Frequency-domain implementation of the transmitted-reference ultra-wideband receiver

    Microsoft Academic Search

    Sebastian Hoyos; Brian M. Sadler

    2006-01-01

    This paper presents a mixed-signal frequency-domain implementation of the autocorrelation receiver used in the detection of ultra-wideband communication signals that are modulated with transmitted-reference signaling. The digital receiver architecture is based on samples provided by an analog-to-digital converter (ADC) in the frequency domain. Among the advantages of the new receiver are the relaxation of the conversion speed achieved by the

  4. A filter bank based ultra-wideband receiver front-end for ranging applications

    Microsoft Academic Search

    Xavier Artiga; Lluís Berenguer

    2009-01-01

    This paper is intended to detail the practical implementation of a receiver front-end, used in an impulse radio ultra-wideband testbed for low data rate communications and ranging. The receiver architecture consists of a filter bank followed by a downconversion stage that relaxes the analog-to-digital converters requirements in terms of input analog bandwidth. The filter bank is implemented by a four-way

  5. Compact CPW-fed circular slot antenna for ultra-wideband applications

    Microsoft Academic Search

    Meie Chen; Junhong Wang

    2008-01-01

    A compact circular slot antenna for ultra-wideband applications is proposed in this letter. The antenna consists of a circular patch and an open annulus, and is fed by coplanar waveguide. The total dimension of the antenna is 30 mmtimes33 mmtimes1.57 mm. The proposed antenna is simulated, fabricated and tested. Results show that a maximum relative impedance bandwidth of more than

  6. A novel orthogonal linearly polarized directional antenna for ultra wideband applications

    Microsoft Academic Search

    Abdelhalim Mohamed; Lotfollah Shafai

    2010-01-01

    In this paper, a novel ultra wideband (UWB) Vee dipole antenna with dual linear orthogonal polarization is introduced. The antenna consists of a 4-arm Vee dipole antenna with a novel arm shape fed by two coaxial cables with UWB baluns. The antenna occupies a volume of (0.44 ?L × 0.44 ?L × 0.44 ?L) without the coaxial balun. The boresight

  7. Printed diversity antenna with cross shape stub for ultra-wideband applications

    Microsoft Academic Search

    Yong Cheng; Wen-jun Lu; Chong-hu Cheng; Wei Cao; Yong Li

    2008-01-01

    A printed diversity antenna for ultra-wideband applications is proposed. The proposed antenna is composed of two square monopoles. In order to reduce the mutual coupling between the two elements, A cross shape stub is introduced. The antenna has been investigated numerically. As is reported, the operation bandwidth of the antenna is from 3.3 GHz to 10.5 GHz. Good isolations can

  8. Half-Sized Vertical Monopole Ultra-Wideband (UWB) Antennas for Mobile Applications

    Microsoft Academic Search

    Anping Zhao; J. Ollikainen

    2007-01-01

    Compact dual-band and triple-band ultra-wideband (UWB) antennas based on a half-sized monopole for mobile applications are proposed. The antennas are placed vertically at one corner of the ground plane of a mobile terminal. A wider antenna impedance bandwidth is achieved by adjusting the length of the lower edge of the monopole. Details of the proposed antenna as well as simulated

  9. DESIGNS ON CPW-FED APERTURE ANTENNA FOR ULTRA-WIDEBAND APPLICATIONS

    Microsoft Academic Search

    Zhong Li; X. Zhang; Guang-Ming Wang; Wen-Ran Su

    2008-01-01

    A novel co-planar waveguide (CPW) ultra-wideband (UWB) aperture antenna is presented. The antenna consists of a rectangular aperture on a printed circuit board ground plane and a mushroom-shaped exciting stub. The mushroom-shaped stub is simple and has less parameter, which is convenient to analyze and optimize. The antenna has a compact aperture size 22 × 13 mm2, fabricated on FR4

  10. Coplanar waveguide-fed dual exponentially tapered slot antennas for ultra-wideband applications

    Microsoft Academic Search

    Yo-Shen Lin; Tzyh-Ghuang Ma; Shyh-Kang Jeng; Chun Hsiung Chen

    2004-01-01

    A uniplanar coplanar waveguide-fed dual exponentially tapered slot antenna is proposed, using a lumped-element impedance-transforming coplanar waveguide-to-slotline transition as the antenna feeding structure. The proposed antenna features a compact size, wide impedance bandwidth, and consistent radiation patterns over the low-band of the ultra-wideband (UWB) spectrum. The characteristics of the proposed antenna, in both the frequency and time domains, are carefully

  11. A Z-shaped band-notched unsymmetric monopole antenna for ultra-wideband application

    Microsoft Academic Search

    Rong Zou; Fu-shun Zhang; Yang Zhu; Kui Dong; Bin Yang

    2010-01-01

    In this article, a simple and printed ultra-wideband (UWB) monopole antenna with band-notched characteristic is presented. The prototype of the proposed antenna is a fan-shaped monopole. By inserting a Z-shaped slot on the radiation element, the 5.5 GHz band-notched characteristic is achieved. Moreover, good radiation patterns and gains within the operating band have been obtained. The detailed design is discussed

  12. Compact diversity antenna with T shape stub for Ultra-wideband applications

    Microsoft Academic Search

    Yong Cheng; Wen-jun Lu; Chong-hu Cheng; Wei Cao; Yong Li

    2008-01-01

    A compact diversity antenna for Ultra-wideband applications is proposed. The proposed antenna is composed of two square monopoles. In order to reduce the mutual coupling between the two elements, A T shape stub is introduced. The antenna has been investigated numerically. As is reported, the operation bandwidth of the antenna is from 3.3GHz to 10.4GHz. Good isolations can be achieved.

  13. Design of a Compact Hexagonal Monopole Antenna for Ultra—Wideband Applications

    Microsoft Academic Search

    Abdo Abdelmonem Shaalan; M. I. Ramadan

    2010-01-01

    This paper presents two design compact hexagonal monopole antennas for ultra-wideband applications. The two antennas are fed\\u000a by a single microstrip line . The Zeland IE3D version 12 is employed for analysis at the frequency band of 4 to 14 GHz which\\u000a has approved as a commercial UWB band. The experimental and simulation results exhibit good agreement together for antenna\\u000a 1.

  14. Planar antennas in LTCC technology with transceiver integration capability for ultra-wideband applications

    Microsoft Academic Search

    Grzegorz Brzezina; Langis Roy; Leonard MacEachern

    2006-01-01

    We present two novel ultra-wideband (UWB) antennas embedded in a low-temperature co-fired ceramic (LTCC) package designed to house the UWB transceiver chip. Given their planar topology, circuit integration possibilities, and compact size, a partial ground-plane triangular monopole antenna (PGP-TM) and an antipodal Vivaldi antenna (AVA) are fully characterized. The performance in both the frequency and time domain are presented. The

  15. A dual band-notched antenna for ultra-wideband applications

    Microsoft Academic Search

    Zhen Hong; Yong-Chang Jiao; Bin Yang; Wei Zhang

    2011-01-01

    This paper presents a new design of printed dual band-notched monopole antenna for ultra-wideband(UWB) applications. Printed on the dielectric substrate, the antenna consists of a disc-like radiator and is fed by a microstrip line. By the use of C-shaped slot and U-shaped slot, the dual band-rejected characteristics are obtained successfully. The effects of variation on slots are both investigated in

  16. FMCW ultra-wideband radar for through-the- wall detection of human beings

    Microsoft Academic Search

    Nadia Maaref; Patrick Millot; Christian Pichot; Odile Picon

    2009-01-01

    An FMCW ultra-wideband radar concept for through-the-wall detection of human beings is presented. Propagation modeling through different types of walls and radar cross section measurements of human beings are given. Power budget and dynamic range are computed and discussed for different situations. The realized UWB FM-CW radar is presented and some fast trials of human beings tracking are shown. This

  17. Ultra-wideband data transmission with double spectral processing of noise waveforms

    Microsoft Academic Search

    V. I. Kalinin

    2005-01-01

    The process of ultra-wideband (UWB) data transmission with double spectral processing of noise waveforms is considered. A\\u000a new method of code spectral modulation based on the interference of perfectly incoherent noise waveforms is proposed. The\\u000a possibility of compressing UWB noise waveforms by means of real-time double spectral processing with subsequent extraction\\u000a of transmitted data has been experimentally demonstrated.

  18. Analysis and processing of ultra wide-band SAR imagery for buried landmine detection

    Microsoft Academic Search

    David Wong; Lawrence Carin

    1998-01-01

    Experimental and theoretical results are presented for ultra wide-band (UWB) synthetic aperture radar (SAR) signatures of buried anti-tank and anti-personnel mines. Such are characterized by resonance-like peaks as well as valleys, across the 50-1200 MHz bandwidth considered. Consequently, frequency subbanding is used to highlight one target over another, of application to discriminating targets (mines) from clutter

  19. Narrowband interference suppression in time-hopping impulse radio ultra-wideband communications

    Microsoft Academic Search

    Jiangzhou Wang; Wong Tat Tung

    2006-01-01

    Ultra-wideband (UWB) technology has been consid- ered an innovative solution for future short-range high-speed wire- less communications. Interference suppression is important for the UWB devices to operate over spectrum occupied by narrowband systems. In this paper, the use of a notch filter in time-hopping im- pulse radio (TH-IR) for UWB communication is considered, where a Gaussian monopulse is employed with

  20. Ultra-Wideband Waveform Generator Based on Optical Pulse-Shaping and FBG Tuning

    Microsoft Academic Search

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

    2008-01-01

    We propose and demonstrate experimentally a prototype for ultra-wideband (UWB) waveform generator based on optical pulse shaping. The time-domain pulse shape is written in the frequency domain, and a single-mode fiber performs frequency-to-time conversion. A U.S. Federal Communications Commission (FCC)-compliant power efficient pulse shape is inscribed in the frequency domain by a fiber Bragg grating (FBG) with an excellent match

  1. Solid-state ultra-wideband pulse generator: Application in bioeffect research

    Microsoft Academic Search

    Ramana K. Sunkam; Jerimiah Hill; Rastko R. Selmic; Donald T. Haynie

    2005-01-01

    This article describes the design and characterization of an ultra-wideband (UWB) pulse generator suitable for biomedical research. The pulser generates nanosecond-long electromagnetic pulses of adjustable rise time, amplitude, and duration, permitting analysis of possible bioeffects over a range of pulse characteristics. Nanosecond rise-time pulses (2.4 ns) of 3.4 kV are achieved in a four-stage pulser circuit using ZTX415 transistors. This

  2. Self-Training Algorithms for Ultra-wideband Radar Target Detection

    Microsoft Academic Search

    Patterson Afb; Atindra K. Mitra; Thomas L. Lewis; Anindya S. Paul; Arnab K. Shaw

    ABSTRACT An ultra-wideband (UWB) synthetic aperture radar (SAR) simulation technique that employs physical and statistical models is developed and presented. This joint physics\\/statistics based technique generates images that have many of the “blob-like” and “spiky” clutter characteristics of UWB radar data in forested regions while avoiding the intensive computations required for the implementation of low-frequency numerical electromagnetic simulation techniques. Approaches

  3. Ultra-wideband bandpass filter with hybrid microstrip\\/CPW structure

    Microsoft Academic Search

    Hang Wang; Lei Zhu; Wolfgang Menzel

    2005-01-01

    A novel ultra-wideband (UWB) bandpass filter (BPF) is presented using the hybrid microstrip and coplanar waveguide (CPW) structure. A CPW nonuniform resonator or multiple-mode resonator (MMR) is constructed to produce its first three resonant modes occurring around the lower end, center, and higher end of the UWB band. Then, a microstrip\\/CPW surface-to-surface coupled line is formed and modeled to allocate

  4. Performance of ultra-wideband communications with suboptimal receivers in multipath channels

    Microsoft Academic Search

    John D. Choi; Wayne E. Stark

    2002-01-01

    The performance of a single-user ultra-wideband (UWB) communication system employing binary block-coded pulse-position modulation (PPM) and suboptimal receivers in multipath channels is considered. The receivers examined include a RAKE receiver with various diversity combining schemes and an autocorrelation receiver, which is used in conjunction with transmitted reference (TR) signaling. A general framework is provided for deriving the performance of these

  5. Design and Fabrication of Ultra-Wideband Baluns Embedded in Multilayer Liquid Crystal Polymer Flex

    Microsoft Academic Search

    Andy C. Chen; Morgan J. Chen; Anh-Vu Pham

    2007-01-01

    In this paper, we present the design and fabrication of ultra-wideband (UWB) baluns embedded in multilayer liquid crystal polymer (LCP) flex. Fabrication techniques are demonstrated for processing these commercially available LCP thin-films by standard PCB equipments. Variations in the LCP thin-film thickness are characterized and compared before and after lamination. Results show good dimensional stability of the material, a critical

  6. System-on-package ultra-wideband transmitter using CMOS impulse generator

    Microsoft Academic Search

    Junwoo Lee; Young-Jin Park; Myunghoi Kim; Changwook Yoon; Joungho Kim; Kwan-Ho Kim

    2006-01-01

    In this paper, a low-cost CMOS ultra-wideband (UWB) impulse transmitter module with a compact form factor is proposed for impulse-radio communications. The module consists of a CMOS impulse generator, a compact bandpass filter (BPF), and a printed planar UWB antenna. The impulse generator is designed using a Samsung 0.35-?m CMOS process for low-cost and low-power fabrication. The measurement shows the

  7. Low Power Digital Baseband for Impulse Radio Ultra-Wideband Transceiver

    Microsoft Academic Search

    Wei Da Toh; Yuanjin Zheng; Chun-Huat Heng

    In this paper, a low power digital baseband to be used together with impulse-radio ultra wideband radio frequency front-end\\u000a has been presented. It can provide received pulse synchronization required for burst mode and low power operation. It also\\u000a overcomes clock drift issue between different transceivers. The clock and data recovery is implemented fully in digital domain\\u000a without the need of

  8. Analog space-time coding for multiantenna ultra-wideband transmissions

    Microsoft Academic Search

    Liuqing Yang; Georgios B. Giannakis

    2004-01-01

    Ultra-wideband (UWB) transmissions have well-doc- umented advantages for low-power, peer-to-peer, and multiple-ac- cess communications. Space-time coding (STC), on the other hand, has gained popularity as an effective means of boosting rates and performance. Existing UWB transmitters rely on a single antenna, while ST coders have mostly focused on digital linearly modulated transmissions. In this paper, we develop ST codes for

  9. IEEE ANTENNAS AND WIRELESS PROPAGATION LETTERS, VOL. 3, 2004 239 Wide-Band Finite Ground Coplanar (FGC)

    E-print Network

    Papapolymerou, Ioannis "John"

    IEEE ANTENNAS AND WIRELESS PROPAGATION LETTERS, VOL. 3, 2004 239 Wide-Band Finite Ground Coplanar Matthew A. Morton and John Papapolymerou, Member, IEEE Abstract--A wide-band finite ground coplanar (FGC (FGC) Interconnects for On-Chip Packaging of RF MEMS Switches Used in Smart Antennas and Phased Arrays

  10. Wideband Propagation Measurements and Channel Implications for Indoor Broadband Wireless Local Area Networks at the 60 GHz Band

    Microsoft Academic Search

    Andreas G. Siamarou

    2003-01-01

    This paper addresses some wideband propagation characteristics for Indoor Broadband Wireless LANs at the 60 GHz band. Important system design characteristics from measured results obtained from two wideband 60 GHz LOS radio links are presented. Measurements had been undertaken using the swept frequency channel sounding method. Analysis from the complex frequency responses in a worst-case scenario have yielded to a

  11. A novel patch antenna for ultra wideband applications

    Microsoft Academic Search

    N. S. Raghava; Asok De; Pushkar Arora; Sagar Malhotra; Rishik Bazaz; Sahil Kapur; Rahul Manocha

    2011-01-01

    ). radiating patch and a circular ring shaped parasitic patch. The design was simulated with the help of IE3D v.14 software and the different parameters of the patch antenna were computed. Results show that the proposed antenna has promising characteristics for UWB applications such as Wireless Personal Area Network (WPAN), microwave imaging for detecting tumors and cancers, home networking etc.

  12. A modified printed monopole antenna for ultra-wideband applications

    Microsoft Academic Search

    S. Adnan; R. A. Abd-Alhameed; S. M. R. Jones; H. I. Hraga; M. S. Bin-Melha; E. A. Elkhazmi

    2010-01-01

    In this paper, a planer printed monopole antenna for Ultra Wide Bandwidth (UWB) applications is presented and discussed. To obtain the required wide response, the base of the monopole is tapered in five steps to match the width of the feeding line as it emerges from the ground plane. A parametric study is carried out for various antenna parameters using

  13. Signal Generation for FMCW Ultra-Wideband Radar

    E-print Network

    Patel, Aqsa Ejaz

    2009-01-01

    . The main objective of the thesis was to produce an ultra linear transmit chirp signal for UWB Radars. This was done by using the Voltage-Controlled-Oscillator (VCO) in a Phase-Locked Loop configuration. To check the linearity of the chirp beat frequency...

  14. Channel Uncertainty in Ultra-Wideband Communication Systems

    Microsoft Academic Search

    Dana Porrat; David N. C. Tse; Serban Nacu

    2007-01-01

    Channel uncertainty limits the achievable data rates of cer tain ultra wide band systems due to the need to estimate the channel. The use of bursty duty-cycled transmission reduces the channel uncertainty because the receiver has to estimate the channel only when transmission takes place; the overall impact on capacity depends on the spectral efficiency of the modulat ion scheme

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

    DOEpatents

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

    2011-06-14

    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.

  16. Land mine detection with an ultra-wideband SAR system

    NASA Astrophysics Data System (ADS)

    Andrieu, Joel; Gallais, Frederic; Mallepeyre, Vincent; Bertrand, Valerie; Beillard, Bruno; Jecko, Bernard; Guillerey, Regis; Legoff, Marc

    2002-08-01

    PULSAR is an Ultra Wide Band (UWB) short pulse Radar developed by the CELAR (French Technical Center for Armament Electronics) and the IRCOM (Research Institute of Microwave and Optical Communications) in order to detect foliage and ground concealed mines. An instrumentation measurement system has been designed and implemented, in particular new 2D broad band antennas with a very low pulse distortion. The clutter suppression is based on background subtraction and wavelet transforms. These data are used to obtain SAR ultra wide band images by transient methods. The following discussion describes the device, the experimental results and the signal processing currently utilized. Future development efforts on this system (generator, acquisition means .) are detailed. At the same time a theoretical study is made to estimate target transient responses captured by the system. So a FDTD code is modified to simulate buried objects detection by the radar.

  17. Optically transparent antenna for Ultra Wide-Band applications

    Microsoft Academic Search

    A. Katsounaros; Y. Hao; N. Collings; W. A. Crossland

    2009-01-01

    We present a novel optically transparent ultra wide band (UWB) disc monopole. The feeding of this antenna is composed by a 50 Omega coplanar waveguide. All the results are analyzed and compared with a non-transparent (but identical) antenna. The antennas are working from 1 GHz up to 8.5 GHz, where the radiation patterns, in both e-plane and h-plane, are plotted

  18. FPGA based Ultra-Wideband pseudo-noise radar

    Microsoft Academic Search

    Amutha Jayakumar; Asha Durafe

    2011-01-01

    A high accuracy experimental platform for Ultra Wide Band (UWB) PN radar performance evaluation has been created. This PN radar platform could be used for the applications such as unmanned- aerial-vehicle anti-collision and short-range distance measurement etc (3). It includes compact size X-band radar transceiver, baseband signal processing in FPGA, high speed analog to digital converter (ADC), and Matlab tools.

  19. An iterative procedure for ultra-wideband imagery of space objects from distributed multi-band radar data

    NASA Astrophysics Data System (ADS)

    Xu, Xiaojian; He, Feiyang

    2014-09-01

    A novel technique is proposed for ultra-wideband imagery of space objects from distributed multi-band radar data. The complex exponential (CE) model is used for representation of ultra-wideband radar signals, where an iterative procedure is developed for optimized model parameter estimation. A subband coherent processing technique is developed which combines the de-noising cross-correlation (DNCC) algorithm with statistical method to obtain the phase and amplitude incoherent parameters (ICP) between subbands. Ultra-wideband data fusion via two-dimensional gapped-data state space approach (2-D GSSA) is then applied to multiple subband signals for supper-resolution imagery. Experiments using computational electromagnetic data from the method of moment (MoM) as well as anechoic chamber measurement data are used to validate the proposed technique and demonstrate its applications.

  20. A wideband frequency-shift keying demodulator for wireless neural stimulation microsystems

    Microsoft Academic Search

    DONG Mian; ZHANG Chun; MAI Song-ping; WANG Zhi-hua; LI Dong-mei

    2006-01-01

    This paper presents a wideband frequency-shift keying (FSK) demodulator suitable for a digital data transmission chain of wireless neural stimulation microsystems such as cochlear implants and retinal prostheses. The demodulator circuit derives a constant frequency clock directly from an FSK carrier, and uses this clock to sample the data bits. The circuit occupies 0.03 mm2 using a 0.6 µm, 2M\\/2P,

  1. A Wideband Frequency-Shift Keying Demodulator for Wireless Neural Stimulation Microsystems

    Microsoft Academic Search

    Mian Dong; Chun Zhang; Songping Mai; Zhihua Wang; Dongmei Li

    2006-01-01

    This paper presents a wideband frequency-shift keying (FSK) demodulator which is suitable for a digital data transmission chain of wireless neural stimulation microsystems such as cochlear implants and retinal prostheses. The demodulator circuit derives a constant frequency clock directly from a FSK carrier, and uses this clock to sample the data bits. The circuit occupies 0.03 mm2 in a 0.6

  2. A wideband frequency-shift keying demodulator for wireless neural stimulation microsystems

    Microsoft Academic Search

    Mian Dong; Chun Zhang; Song-ping Mai; Zhi-hua Wang; Dong-mei Li

    2006-01-01

    This paper presents a wideband frequency-shift keying (FSK) demodulator suitable for a digital data transmission chain of\\u000a wireless neural stimulation microsystems such as cochlear implants and retinal prostheses. The demodulator circuit derives\\u000a a constant frequency clock directly from an FSK carrier, and uses this clock to sample the data bits. The circuit occupies\\u000a 0.03 mm2 using a 0.6 ?m, 2M\\/2P,

  3. Design and development of a small compact ultra wideband antenna

    NASA Astrophysics Data System (ADS)

    Qurratulain; Chattoraj, Neela

    2013-04-01

    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.

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

    PubMed Central

    Rotaru, Mihai; Sykulski, Jan

    2010-01-01

    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

  5. Solid-state ultra-wideband pulse generator: Application in bioeffect research

    NASA Astrophysics Data System (ADS)

    Sunkam, Ramana K.; Hill, Jerimiah; Selmic, Rastko R.; Haynie, Donald T.

    2005-05-01

    This article describes the design and characterization of an ultra-wideband (UWB) pulse generator suitable for biomedical research. The pulser generates nanosecond-long electromagnetic pulses of adjustable rise time, amplitude, and duration, permitting analysis of possible bioeffects over a range of pulse characteristics. Nanosecond rise-time pulses (2.4 ns) of 3.4 kV are achieved in a four-stage pulser circuit using ZTX415 transistors. This device has been used to assess exposure bioeffects to UWB pulses of the model system E. coli.

  6. Propagation of ultra wide-band signals in lossy dispersive media

    Microsoft Academic Search

    Y. Pinhasi; A. Yahalom; S. Petnev

    2008-01-01

    Development of a channel model for continuous frequencies enables the analysis of communications in an ultra wide band wireless network in indoor environment including a single transmitting and a single receiving antenna. In this work we will describe a model taking into account multiple reflections which are a consequence of the room in which both transmitter and receiver are localized

  7. This paper describes the system architecture and circuit design constraints for a proposed Ultra-Wideband radio

    E-print Network

    Southern California, University of

    in the presence of white noise [8]. Even in the presence of colored noise or narrowband interferers an FIR filter of bandwidth. Reception, after gain and fil- tering, occurs in a bank of A/D converters which capture for imaging applications, at power levels similar to Part 15 [1]. Ultra-Wideband (UWB) radios communicate

  8. A review on modulation techniques in multiband-orthogonal frequency division multiplexing in ultra-wideband channel

    Microsoft Academic Search

    Chempaka Mohd Din; Wahidah Mansor; Roslina Mohamad

    2011-01-01

    This paper describes a review on mapping or modulation techniques used in multiband orthogonal frequency division multiplexing (MB-OFDM) in ultra- wideband (UWB) channel. QAM, BPSK and QPSK modulation techniques are commonly used in this system due to their smooth power spectrum, low bit error rate (BER) and low receiver complexity. The new constant envelop modulation technique is proposed since it

  9. Ultra-Wideband GPR Imaging of the Vaucluse Karst Aquifer

    NASA Astrophysics Data System (ADS)

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

    2008-12-01

    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.

  10. Wearable and Ultra Low Power Wireless System for Physiological Monitoring

    Microsoft Academic Search

    C. P. Figueiredo; J. Cardona; K.-P. Hoffmann; P. M. Mendes

    \\u000a A wearable and ultra low-power wireless system is proposed for remote monitoring of physiological parameters. The developed\\u000a system monitors the electrocardiogram (ECG), activity and temperature, transmitting the signals to a remote base station via\\u000a a wireless link, and also allows for wireless battery recharging. An acquisition module was designed solely with low power\\u000a and small form factor electronic components. The

  11. 100 GHz ultra-wideband (UWB) fiber-to-the-antenna (FTTA) system for in-building and in-home networks.

    PubMed

    Chow, C W; Kuo, F M; Shi, J W; Yeh, C H; Wu, Y F; Wang, C H; Li, Y T; Pan, C L

    2010-01-18

    Fiber-to-the-antenna (FTTA) system can be a cost-effective technique for distributing high frequency signals from the head-end office to a number of remote antenna units via passive optical splitter and propagating through low-loss and low-cost optical fibers. Here, we experimentally demonstrate an optical ultra-wideband (UWB) - impulse radio (IR) FTTA system for in-building and in-home applications. The optical UWB-IR wireless link is operated in the W-band (75 GHz - 110 GHz) using our developed near-ballistic unitraveling-carrier photodiode based photonic transmitter (PT) and a 10 GHz mode-locked laser. 2.5 Gb/s UWB-IR FTTA systems with 1,024 high split-ratio and transmission over 300 m optical fiber are demonstrated using direct PT modulation. PMID:20173867

  12. Exposure assessment procedures in presence of wideband digital wireless networks.

    PubMed

    Trinchero, D

    2009-12-01

    The article analyses the applicability of traditional methods, as well as recently proposed techniques, to the exposure assessment of electromagnetic field generated by wireless transmitters. As is well known, a correct measurement of the electromagnetic field is conditioned by the complexity of the signal, which requires dedicated instruments or specifically developed extrapolation techniques. Nevertheless, it is also influenced by the typology of the deployment of the transmitting and receiving stations, which varies from network to network. These aspects have been intensively analysed in the literature and several cases of study are available for review. The present article collects the most recent analyses and discusses their applicability to different scenarios, typical of the main wireless networking applications: broadcasting services, mobile cellular networks and data access provisioning infrastructures. PMID:19914966

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

    PubMed Central

    Thiel, Florian; Kosch, Olaf; Seifert, Frank

    2010-01-01

    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

  14. Design, Modeling and Numerical Analysis of Microwave and Optical Devices: The Multi-band Patch Antenna, Ultra Wideband Ring Filter and Plasmonic Waveguide Coupler

    E-print Network

    Liu, Ya-Chi

    2014-01-14

    In this dissertation, three devices are studied and devised for the applications in microwave and optical communication: (1) Multiband Patch Antenna, (2) Ultra-Wideband Band Pass Ring Filter and (3) Plasmonic Waveguide Coupler with High Coupling...

  15. UWB Radio Module Design for Wireless Intelligent Systems-From Specification to Implementation

    Microsoft Academic Search

    Meigen Shen; Tero Koivisto; Teemu Peltonen; Li-Rong Zheng; Esa Tjukanoff; Hannu Tenhunen

    2005-01-01

    In this paper, we designed an impulse-based ultra wideband (UWB) radio module (low band) for wireless intelligent system applications such as radio frequency identification (RFID) and wireless sensor networks (WSN). The UWB radio module includes transceiver block, baseband process unit and power management block. The transceiver circuits include Gaussian pulse generator, wideband low noise amplifier (LNA), multiplier, integrator and timing

  16. 3D SAR image formation for underground targets using ultra-wideband (UWB) radar

    NASA Astrophysics Data System (ADS)

    Nguyen, Lam; Dogaru, Traian; Innocenti, Roberto

    2009-05-01

    This paper analyzes the application of ultra-wideband ground-penetrating radar (GPR) in a down-looking configuration for the detection of buried targets. As compared to previous studies, where target detection algorithms have been developed based on the radar range profiles alone (pre-focus data), we investigate the potential performance improvement by forming synthetic aperture radar (SAR) images of the targets. This becomes important in scenarios with small signal-to-noise or signal-to-clutter ratios. Our three-dimensional (3-D) image formation algorithm is based on the backprojection technique. We apply this method to radar scattering data obtained through computer simulation by the finite-difference time-domain (FDTD) technique. Our analysis demonstrates the advantages of using focused SAR images versus the pre-focus range profiles. We also perform a parametric study of several physical factors that could affect the image quality.

  17. Ultra wide-band localization and SLAM: a comparative study for mobile robot navigation.

    PubMed

    Segura, Marcelo J; Auat Cheein, Fernando A; Toibero, Juan M; Mut, Vicente; Carelli, Ricardo

    2011-01-01

    In this work, a comparative study between an Ultra Wide-Band (UWB) localization system and a Simultaneous Localization and Mapping (SLAM) algorithm is presented. Due to its high bandwidth and short pulses length, UWB potentially allows great accuracy in range measurements based on Time of Arrival (TOA) estimation. SLAM algorithms recursively estimates the map of an environment and the pose (position and orientation) of a mobile robot within that environment. The comparative study presented here involves the performance analysis of implementing in parallel an UWB localization based system and a SLAM algorithm on a mobile robot navigating within an environment. Real time results as well as error analysis are also shown in this work. PMID:22319397

  18. Free space optical ultra-wideband communications over atmospheric turbulence channels.

    PubMed

    Davaslio?lu, Kemal; Ca?iral, Erman; Koca, Mutlu

    2010-08-01

    A hybrid impulse radio ultra-wideband (IR-UWB) communication system in which UWB pulses are transmitted over long distances through free space optical (FSO) links is proposed. FSO channels are characterized by random fluctuations in the received light intensity mainly due to the atmospheric turbulence. For this reason, theoretical detection error probability analysis is presented for the proposed system for a time-hopping pulse-position modulated (TH-PPM) UWB signal model under weak, moderate and strong turbulence conditions. For the optical system output distributed over radio frequency UWB channels, composite error analysis is also presented. The theoretical derivations are verified via simulation results, which indicate a computationally and spectrally efficient UWB-over-FSO system. PMID:20721053

  19. Experimental implant communication of high data rate video using an ultra wideband radio link.

    PubMed

    Chávez-Santiago, Raúl; Balasingham, Ilangko; Bergsland, Jacob; Zahid, Wasim; Takizawa, Kenichi; Miura, Ryu; Li, Huan-Bang

    2013-01-01

    Ultra wideband (UWB) is one of the radio technologies adopted by the IEEE 802.15.6™-2012 standard for on-body communication in body area networks (BANs). However, a number of simulation-based studies suggest the feasibility of using UWB for high data rate implant communication too. This paper presents an experimental verification of said predictions. We carried out radio transmissions of H.264/1280×720 pixels video at 80 Mbps through a UWB multiband orthogonal frequency division multiplexing (MB-OFDM) interface in a porcine chirurgical model. The results demonstrated successful transmission up to a maximum depth of 30 mm in the abdomen and 33 mm in the thorax within the 4.2-4.8 GHz frequency band. PMID:24110901

  20. Ultra Wide-Band Localization and SLAM: A Comparative Study for Mobile Robot Navigation

    PubMed Central

    Segura, Marcelo J.; Auat Cheein, Fernando A.; Toibero, Juan M.; Mut, Vicente; Carelli, Ricardo

    2011-01-01

    In this work, a comparative study between an Ultra Wide-Band (UWB) localization system and a Simultaneous Localization and Mapping (SLAM) algorithm is presented. Due to its high bandwidth and short pulses length, UWB potentially allows great accuracy in range measurements based on Time of Arrival (TOA) estimation. SLAM algorithms recursively estimates the map of an environment and the pose (position and orientation) of a mobile robot within that environment. The comparative study presented here involves the performance analysis of implementing in parallel an UWB localization based system and a SLAM algorithm on a mobile robot navigating within an environment. Real time results as well as error analysis are also shown in this work. PMID:22319397

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

    E-print Network

    Davaslioglu, Kemal

    2013-01-01

    A composite impulse radio ultra-wideband (IR-UWB) communication system is presented. The proposed system model aims to transmit UWB pulses over several kilometers through free-space optical (FSO) links and depending on the link design, the electrical estimates of the FSO system can be directly used or distributed to end-user through radio-frequency (RF) links over short ranges. However, inhomogeneities on the FSO transmission path cause random fluctuations in the received signal intensity and these effects induced by atmospheric turbulence closely effect the system performance. Several distinct probability distributions based on experimental measurements are used to characterize FSO channels and using these probabilistic models, detection error probability analysis of the proposed system for different link designs are carried out under weak, moderate and strong turbulence conditions. The results of the analysis show that depending on the atmospheric conditions, system performance of the composite link can hav...

  2. Contemporary Wireless Technology

    NSDL National Science Digital Library

    Wireless means radio in its broadest sense. However, in the early 21st century, wireless refers primarily to the two dominant forms of wireless: cell phones and wireless local area networks (WLANs). This module describes the idea behind the cellular telephone system, how it works, and the primary technologies used in the US and throughout the world. This module also introduces the wireless local area network or WLAN. WLANs are radio-linked computers that are part of a larger network. The wireless links make portability and mobility of computers possible. This module also briefly introduces four common forms of short- range wireless: Bluetooth, ZigBee, ultra wideband (UWB) and RFID.

  3. 862 IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS, VOL. 12, NO. 2, FEBRUARY 2013 Unitary Differential Space-Time-Frequency Codes

    E-print Network

    Lübeck, Universität zu

    , namely multi-band orthogonal frequency division multiplexing ultra-wideband (MB-OFDM UWB) [3], [4 Differential Space-Time-Frequency Codes for MB-OFDM UWB Wireless Communications L. C. Tran, Member, IEEE, A-input multiple-output (MIMO), multi- band orthogonal frequency division multiplexing (MB-OFDM) ultra-wideband

  4. IEEE Wireless Communications April 200546 1536-1284/05/$20.00 2005 IEEE MODULATION, CODING AND SIGNAL PROCESSING FOR

    E-print Network

    Chen, Yuanzhu Peter

    -output antenna systems. Ultra wideband is of particular interest for fourth-generation wire- less applications have been considered for 4G wireless sys- tems: ultra wideband (UWB), orthogonal frequency-division multiplexing (OFDM), and multi-input multi-output (MIMO) antenna sys- tems. UWB is particularly attractive due

  5. An Electronic Circuit System for Time-Reversal of Ultra-Wideband Short Impulses Based on Frequency-Domain Approach

    Microsoft Academic Search

    Huiqing Zhai; Shaoshu Sha; Varun K. Shenoy; Sungyong Jung; Mingyu Lu; Kyoungwon Min; Sungchul Lee; Dong S. Ha

    2010-01-01

    In this paper, a compact and low-cost electronic circuit system is designed for time-reversal of ultra-wideband short impulses (with nanosecond and sub-nanosecond temporal durations). A frequency-domain approach is adopted to avoid high sampling rate in time. Specifically, the proposed system obtains the discrete spectra of input impulses first; then realizes time-reversal in frequency domain; and finally synthesizes the time-reversed impulses

  6. A Compact, ESD-Protected, SiGe BiCMOS LNA for Ultra-Wideband Applications

    Microsoft Academic Search

    Karan Bhatia; Sami Hyvonen; Elyse Rosenbaum

    2007-01-01

    Two 3.65-mW, ESD-protected, BiCMOS ultra-wideband low-noise amplifiers (LNAs) for operation up to 10 GHz are presented. These common-base LNAs achieve significant savings in die area over more widely used cascoded common-emitter LNAs because they do not use an LC input matching network. A design with a shunt peaked load achieves a high S21 (17-19 dB) and low noise figure (NF)

  7. An ultra-wideband printed monopole antenna with the gain enhanced using a surface-mounted short horn

    Microsoft Academic Search

    Y. Ranga; Karu P. Esselle; A. R. Weily; A. K. Verma

    2010-01-01

    An ultra-wideband printed monopole antenna, improved by attaching a short two-plate horn to its surface, is reported in this paper. The short horn, which has a slant length of 45 mm and a total physical height of 46.9 mm, significantly increases the gain of the printed monopole antenna at lower frequencies where the gain of the monopole is otherwise low,

  8. On Space-Time Coding With Pulse Position and Amplitude Modulations for Time-Hopping Ultra-Wideband Systems

    Microsoft Academic Search

    Chadi Abou-rjeily; Jean-claude Belfiore

    2007-01-01

    In this work, we propose novel families of space-time (ST) block codes that can be associated with impulse radio ultra-wideband (IR-UWB) communication systems. The carrier-less nature of this nonconventional totally real transmission technique necessitates the construction of new suitable coding schemes. In fact, the last generation of complex-valued ST codes (namely, the perfect codes) cannot be associated with IR-UWB systems

  9. Ultra low-power radio design for wireless sensor networks

    Microsoft Academic Search

    C. Enz; N. Scolari; U. Yodprasit

    2005-01-01

    Power consumption and size are the most important challenges faced when designing radios for distributed wireless sensor networks (WSN). Reducing power consumption requires optimization across all the layers of the communication systems. Although the MAC layer plays a crucial role in the overall energy efficiency, the radio remains one of the bottleneck for implementing ultra low-power WSN. The power consumption

  10. Ultra-compact optical true time delay device for wideband phased array radars.

    SciTech Connect

    Spahn, Olga Blum; Rabb, David J. (AFRL/RYJM, WPAFB, OH); Cowan, William D.; McCray, David L. (Ohio State University, Columbus, OH); Rowe, Delton, J. (Northrop Grumman Aerospace Systems, Redondo Beach, CA); Flannery, Martin R. (Northrop Grumman Aerospace Systems, Redondo Beach, CA); Yi, Allen Y. (Ohio State University, Columbus, OH); Ho, James G. (Northrop Grumman Aerospace Systems, Redondo Beach, CA); Anderson, Betty Lise (Ohio State University, Columbus, OH)

    2010-02-01

    An ultra-compact optical true time delay device is demonstrated that can support 112 antenna elements with better than six bits of delay in a volume 16-inch x 5-inch x 4-inch including the box and electronics. Free-space beams circulate in a White cell, overlapping in space to minimize volume. The 18 mirrors are slow-tool diamond turned on two substrates, one at each end, to streamline alignment. Pointing accuracy of better than 10 {micro}rad is achieved, with surface roughness {approx}45 nm rms. A MEMS tip-style mirror array selects among the paths for each beam independently, requiring {approx}100 {micro}s to switch the whole array. The micromirrors have 1.4{sup o} tip angle and three stable states (east, west, and flat). The input is a fiber-and-microlens array, whose output spots are re-imaged multiple times in the White cell, striking a different area of the single MEMS chip in each of 10 bounces. The output is converted to RF by an integrated InP wideband optical combiner detector array. Delays were accurate to within 4% (shortest delay) to 0.03% (longest mirror train). The fiber-to-detector insertion loss is 7.82 dB for the shortest delay path.

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

    NASA Technical Reports Server (NTRS)

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

    2010-01-01

    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.

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

    PubMed

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

    2010-01-01

    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

  13. Achieving wide-band linear-to-circular polarization conversion using ultra-thin bi-layered metasurfaces

    NASA Astrophysics Data System (ADS)

    Li, Yongfeng; Zhang, Jieqiu; Qu, Shaobo; Wang, Jiafu; Zheng, Lin; Pang, Yongqiang; Xu, Zhuo; Zhang, Anxue

    2015-01-01

    In this paper, we propose to achieve wideband linear-to-circular (LTC) polarization conversion by ultra-thin bi-layered metasurfaces. As an example, an LTC polarization conversion metasurface operating in 11.4-14.3 GHz is designed and fabricated, which is composed of two layers of metallic pattern arrays separated by a 1.5 mm-thick dielectric spacer. When linearly polarized waves impinge on the bi-layered metasurface, LTC polarization conversion transmission is greater than 90% over a wide frequency range from 11.0 GHz to 18.3 GHz. Meanwhile, the axis ratio is lower than 3 dB in 9.8-18.3 GHz. This wide-band and highly efficient LTC polarization conversion transmission is analyzed theoretically. The measured LTC polarization conversion transmissions are well consistent with the simulated results.

  14. UWB radio module design for wireless sensor networks

    Microsoft Academic Search

    Meigen Shen; Tero Koivisto; Teemu Peltonen; Li-Rong Zheng; Esa Tjukanoff; H. Tenhunerf

    2005-01-01

    In this paper, we have designed an impulse-based ultra wideband (UWB) radio module for wireless sensor networks (WSN) applications. The UWB radio module includes transceiver block, baseband process unit and power management block. The transceiver block includes Gaussian pulse generator, wideband low noise amplifier (LNA), multiplier, integrator and timing circuits, which use 0.18?m, 1P6M CMOS technology. The wideband LNA has

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

    SciTech Connect

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

    1992-11-01

    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.

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

    SciTech Connect

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

    1992-01-01

    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.

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

    NASA Astrophysics Data System (ADS)

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

    2013-05-01

    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 128 ns 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 2.5 nm. 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 64 ns, 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.

  18. Eco: Ultra-Wearable and Expandable Wireless Sensor Platform

    Microsoft Academic Search

    Pai H. Chou

    2006-01-01

    Eco is a self-contained, ultra-wearable and expandable wireless sensor platform under 1cm 3. Previous platforms make trade-offs between size or expandability. Eco achieves both with a novel flex-PCB expansion connector for digi- tal\\/analog I\\/O, firmware programming, and battery charg- ing. It can be folded up without obstruction or clipped off if expandability is no longer needed. Only 15% the volume

  19. All optical ultra-wideband signal generation and transmission using mode-locked laser incorporated with add-drop microring resonator

    NASA Astrophysics Data System (ADS)

    Soltanian, M. R. K.; Amiri, I. S.; Alavi, S. E.; Ahmad, H.

    2015-06-01

    The novel technique for generating the robust, ultra-wideband (UWB) signal in the optical domain using a mode-locked laser incorporated with an add-drop microring resonator filter is presented. In order to enable the down conversion of the UWB signal to the RF domain, two wavelength ranges 1553.72 and 1553.92?nm, which are 24.65?GHz apart from each other, are used. These wavelengths were generated based on a single longitudinal mode (SLM) dual-wavelength fiber laser in a laser ring cavity. The upper wavelength of the generated dual-wavelength laser is modulated with the UWB spectrum using an optical carrier suppression (OCS) scheme and the lower wavelength is kept unmodulated. After beating the modulated and unmodulated wavelength by launching into the photodiode, the 24?GHz UWB signal can be generated to be applied to UWB over fiber (UWBoF) technology. The error vector magnitude (EVM) for the signal transmission was calculated and the EVM below 10% is achieved for 25?Km optical and 20?m wireless links.

  20. Joint Scale-Lag Diversity in Mobile Ultra-Wideband Adam R. Margetts and Philip Schniter

    E-print Network

    Schniter, Philip

    -wideband (UWB) direct sequence spread spectrum communication system. Based on a uniform ring of scatterers model may be temporally delayed by a different amount. For UWB direct- sequence spread spectrum (DSSS

  1. CMOS Integrated Circuit Design for Ultra-Wideband Transmitters and Receivers 

    E-print Network

    Xu, Rui

    2010-10-12

    and Bluetooth are mostly narrow band based. To implement UWB technologies on CMOS imposes the development of CMOS front-end building blocks which can perform wideband signal processing such as amplifying, frequency conversion, frequency generation as well...

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

    NASA Astrophysics Data System (ADS)

    Jain, Vipul

    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.

  3. Model-based sub-Nyquist sampling and reconstruction technique for ultra-wideband (UWB) radar

    NASA Astrophysics Data System (ADS)

    Nguyen, Lam; Tran, Trac D.

    2010-04-01

    The Army Research Lab has recently developed an ultra-wideband (UWB) synthetic aperture radar (SAR). The radar has been employed to support proof-of-concept demonstration for several concealed target detection programs. The radar transmits and receives short impulses to achieve a wide-bandwidth from 300 MHz to 3000 MHz. Since the radar directly digitizes the wide-bandwidth receive signals, the challenges is to how to employ relatively slow and inexpensive analog-to-digital (A/D) converters to sample the signals with a rate that is greater than the minimum Nyquist rate. ARL has developed a sampling technique that allows us to employ inexpensive A/D converters (ADC) to digitize the widebandwidth signals. However, this technique still has a major drawback due to the longer time required to complete a data acquisition cycle. This in turn translates to lower average power and lower effective pulse repetition frequency (PRF). Compressed Sensing (CS) theory offers a new approach in data acquisition. From the CS framework, we can reconstruct certain signals or images from much fewer samples than the traditional sampling methods, provided that the signals are sparse in certain domains. However, while the CS framework offers the data compression feature, it still does not address the above mentioned drawback, that is the data acquisition must be operated in equivalent time since many global measurements (obtained from global random projections) are required as depicted by the sensing matrix ? in the CS framework. In this paper, we propose a new technique that allows the sub-Nyquist sampling and the reconstruction of the wide-bandwidth data. In this technique, each wide-bandwidth radar data record is modeled as a superposition of many backscatter signals from reflective point targets. The technique is based on direct sparse recovery using a special dictionary containing many time-delayed versions of the transmitted probing signal. We demonstrate via simulated as well as collected data that our design offers real-time (with single observation as oppose to equivalent-time with many observations) data acquisition of the wide-bandwidth radar signals using the sub-Nyquist sampling rate.

  4. Eco: Ultra-Wearable and Expandable Wireless Sensor Platform Chulsung Park and Pai H. Chou

    E-print Network

    Chou, Pai H.

    Eco: Ultra-Wearable and Expandable Wireless Sensor Platform Chulsung Park and Pai H. Chou Center,phchou}@uci.edu Abstract Eco is a self-contained, ultra-wearable and expandable wireless sensor platform under 1cm3. Previous platforms make trade-offs between size or expandability. Eco achieves both with a novel flex

  5. Simulation Platform for Wireless Sensor Networks Based on Impulse Radio Ultra Wide Band

    E-print Network

    Paris-Sud XI, Université de

    Simulation Platform for Wireless Sensor Networks Based on Impulse Radio Ultra Wide Band Abdoulaye Radio Ultra Wide Band (IR-UWB) is a promising technology to address Wireless Sensor Network (WSN into account the pulse collision by dealing with the pulse propagation delay. We also modelled MAC protocols

  6. A wideband dual-antenna receiver for wireless recording from animals behaving in large arenas.

    PubMed

    Lee, Seung Bae; Yin, Ming; Manns, Joseph R; Ghovanloo, Maysam

    2013-07-01

    A low-noise wideband receiver (Rx) is presented for a multichannel wireless implantable neural recording (WINeR) system that utilizes time-division multiplexing of pulse width modulated (PWM) samples. The WINeR-6 Rx consists of four parts: 1) RF front end; 2) signal conditioning; 3) analog output (AO); and 4) field-programmable gate array (FPGA) back end. The RF front end receives RF-modulated neural signals in the 403-490 MHz band with a wide bandwidth of 18 MHz. The frequency-shift keying (FSK) PWM demodulator in the FPGA is a time-to-digital converter with 304 ps resolution, which converts the analog pulse width information to 16-bit digital samples. Automated frequency tracking has been implemented in the Rx to lock onto the free-running voltage-controlled oscillator in the transmitter (Tx). Two antennas and two parallel RF paths are used to increase the wireless coverage area. BCI-2000 graphical user interface has been adopted and modified to acquire, visualize, and record the recovered neural signals in real time. The AO module picks three demultiplexed channels and converts them into analog signals for direct observation on an oscilloscope. One of these signals is further amplified to generate an audio output, offering users the ability to listen to ongoing neural activity. Bench-top testing of the Rx performance with a 32-channel WINeR-6 Tx showed that the input referred noise of the entire system at a Tx-Rx distance of 1.5 m was 4.58 ?V rms with 8-bit resolution at 640 kSps. In an in vivo experiment, location-specific receptive fields of hippocampal place cells were mapped during a behavioral experiment in which a rat completed 40 laps in a large circular track. Results were compared against those acquired from the same animal and the same set of electrodes by a commercial hardwired recording system to validate the wirelessly recorded signals. PMID:23428612

  7. A Wideband Dual-Antenna Receiver for Wireless Recording From Animals Behaving in Large Arenas

    PubMed Central

    Lee, Seung Bae; Yin, Ming; Manns, Joseph R.

    2014-01-01

    A low-noise wideband receiver (Rx) is presented for a multichannel wireless implantable neural recording (WINeR) system that utilizes time-division multiplexing of pulse width modulated (PWM) samples. The WINeR-6 Rx consists of four parts: 1) RF front end; 2) signal conditioning; 3) analog output (AO); and 4) field-programmable gate array (FPGA) back end. The RF front end receives RF-modulated neural signals in the 403–490 MHz band with a wide bandwidth of 18 MHz. The frequency-shift keying (FSK) PWM demodulator in the FPGA is a time-to-digital converter with 304 ps resolution, which converts the analog pulse width information to 16-bit digital samples. Automated frequency tracking has been implemented in the Rx to lock onto the free-running voltage-controlled oscillator in the transmitter (Tx). Two antennas and two parallel RF paths are used to increase the wireless coverage area. BCI-2000 graphical user interface has been adopted and modified to acquire, visualize, and record the recovered neural signals in real time. The AO module picks three demultiplexed channels and converts them into analog signals for direct observation on an oscilloscope. One of these signals is further amplified to generate an audio output, offering users the ability to listen to ongoing neural activity. Bench-top testing of the Rx performance with a 32-channel WINeR-6 Tx showed that the input referred noise of the entire system at a Tx–Rx distance of 1.5 m was 4.58 ?Vrms with 8-bit resolution at 640 kSps. In an in vivo experiment, location-specific receptive fields of hippocampal place cells were mapped during a behavioral experiment in which a rat completed 40 laps in a large circular track. Results were compared against those acquired from the same animal and the same set of electrodes by a commercial hardwired recording system to validate the wirelessly recorded signals. PMID:23428612

  8. Velocity compensation based Ultra-Wide bandwidth wireless moving target localization

    Microsoft Academic Search

    Ding Hong; Li Xin; Huang Xiao-tao; Li Zheng-rong

    2009-01-01

    The extremely high resolution of Ultra-Wideband (UWB) signal in time domain and range measurement precision makes it advantageous in precise positioning. The algorithm based on averaging TOA is effective in reducing error in the precision positioning of stationary targets. But for moving targets, severe error will be introduced which makes the method unusable. This paper presents two means to improve

  9. A COMPACT COMPOSITE BROAD STOPBAND ELLIPTIC-FUNCTION LOW-PASS FILTER FOR ULTRA WIDE-BAND APPLICATIONS USING INTERDIGITAL CAPACITORS

    Microsoft Academic Search

    Mehdi Nosrati; Tayeb Faraji; Zahra Atlasbaf

    2009-01-01

    Abstract—A compact,composite ultra wide-band elliptic-function low-pass filter is introduced by combining in cascade a microstrip stepped-impedance resonator using interdigital capacitor and,an admittance inverter. A triple cascade low-pass filter is designed, analyzed and tested with this technique accompanied by its equivalent circuit model. This composition acts similar to a composite filter with desired attenuation and matching properties in order to obtain

  10. Interactive presentation: Behavioral modeling of delay-locked loops and its application to jitter optimization in ultra wide-band impulse radio systems

    Microsoft Academic Search

    E. Barajas; R. Cosculluela; D. Coutinho; D. Mateo; J. L. González; I. Cairò; S. Banda; M. Ikeda

    2007-01-01

    This paper presents a behavioral model of a delay-locked loop (DLL) used to generate the timing signals in an integrated ultra wide-band (UWB) impulse radio (IR) system. The requirements of these timing signals in the context of UWB-IR systems are reviewed. The behavioral model includes a modeling of the various noise sources in the DLL that produce output jitter. The

  11. Behavioral Modeling of Delay-Locked Loops and its Application to Jitter Optimization in Ultra Wide-Band Impulse Radio Systems

    Microsoft Academic Search

    E. Barajas; R. Cosculluela; D. Coutinho; D. Mateo; J. L. Gonzalez; S. Banda; M. Ikeda

    2007-01-01

    This paper presents a behavioral model of a delay-locked loop (DLL) used to generate the timing signals in an integrated ultra wide-band (UWB) impulse radio (IR) system. The requirements of these timing signals in the context of UWB-IR systems are reviewed. The behavioral model includes a modeling of the various noise sources in the DLL that produce output jitter. The

  12. An all-digital transmitter for pulsed ultra-wideband communication

    E-print Network

    Mercier, Patrick Philip

    2008-01-01

    Applications like sensor networks, medical monitoring, and asset tracking have led to a demand for energy-efficient and low-cost wireless transceivers. These types of applications typically require low effective data rates, ...

  13. Development of an Ultra-Wideband Radar System for Vehicle Detection at Railway Crossings

    E-print Network

    Kansas, University of

    Laboratory, Information Technology and Telecommunications Center Abstract ­ This paper describes an ultra or that they can beat the train. One method being studied by the railroad industry to stop these drive

  14. Design of a wideband antenna package with a compact spatial notch filter for wireless applications

    Microsoft Academic Search

    Judo Yeo; R. Mittra

    2002-01-01

    This paper describes a compact package, comprising a wideband antenna with a compact spatial notch filter, useful for RF applications requiring a high rate of data transfer. The use of fractal concepts helps to reduce the package to almost half the normal size, and to realize a much sharper band-stop than would be possible with a conventional filter. The antenna

  15. Compound strategies of coding, equalization, and space diversity for wide-band TDMA indoor wireless channels

    Microsoft Academic Search

    Charles L. B. Despins; David D. Falconer; Samy A. Mahmoud

    1992-01-01

    Compound strategies of equalization and space diversity in the form of an optimum baseband combiner are attractive for wideband time division multiple access (TDMA) portable communication radio links in order to combat dispersive fading and cochannel interference. The authors investigate the performance of such a scheme in conjunction with convolutional coding and soft-decision Viterbi decoding via a semianalytical technique based

  16. A capacity improvement and call admission control algorithm for wideband CDMA wireless networks

    Microsoft Academic Search

    O. O. Oyefuga; M. K. Gurcan

    2002-01-01

    Wideband CDMA (W-CDMA) has been proposed as the radio access technology for 3G mobile communication systems. It provides the ability to deliver packet based multimedia services between the base station and the mobile device. Various studies have shown that major restrictions on system capacity and congestion occur at this air interface due to the limited transmission resources. Several papers have

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

    PubMed

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

    2013-01-01

    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

  18. ASYMPTOTIC ANALYSIS OF CHANNEL DIVISION MULTIPLE ACCESS SCHEMES FOR ULTRA-WIDEBAND SYSTEMS

    E-print Network

    Paris-Sud XI, Université de

    , low cost indoor communication systems such as Wireless Local Area Network (WLAN) and Personal Area the asymptotic capacity of the ChDMA scheme when the number of users and the number of frequency dimensions radio technology due to the large available bandwidth. UWB systems enables high data rates at short

  19. Localization via ultra-wideband radios: a look at positioning aspects for future sensor networks

    Microsoft Academic Search

    Sinan Gezici; Zhi Tian; Georgios B. Giannakis; Hisashi Kobayashi; Andreas F. Molisch; H. Vincent Poor; Zafer Sahinoglu

    2005-01-01

    UWB technology provides an excellent means for wireless positioning due to its high resolution capability in the time domain. Its ability to resolve multipath components makes it possible to obtain accurate location estimates without the need for complex estimation algorithms. In this article, theoretical limits for TOA estimation and TOA-based location estimation for UWB systems have been considered. Due to

  20. The Roles of Ultra Wideband in Cognitive Networks Mustafa E. Sahin, Sadia Ahmed, and Huseyin Arslan

    E-print Network

    Arslan, Hüseyin

    , · adjustable data rate, adaptive transmit power, information security, and limited cost, · negligible wireless communications, and it has been gaining significant interest among the academia, industry of cognitive radio devices that share information is defined as a pure cognitive network [2]. Cog- nitive

  1. Progress In Electromagnetics Research Letters, Vol. 31, 121129, 2012 ANTENNA ULTRA WIDEBAND ENHANCEMENT BY

    E-print Network

    Paris-Sud XI, Université de

    propose an ultra wide band antenna enhancement by non-uniform matching. Indeed, rectangular shaped planar design considerations for practical applications of microstrip antennas. Eventually, researches to reach in allied branches are now being investigated in antennas applications. Various recent basic principles

  2. Ultra-Wideband Optical Modulation Spectrometer (OMS) Development: Study of the Optical Setup of a Wide-Band Optical Modulation Spectrometer

    NASA Technical Reports Server (NTRS)

    Tolls, Volker; Stringfellow, Guy (Technical Monitor)

    2001-01-01

    The purpose of this study is to advance the design of the optical setup for a wide-band Optical Modulation Spectrometer (OMS) for use with astronomical heterodyne receiver systems. This report describes the progress of this investigation achieved from March until December 2001.

  3. Efficient Signaling Schemes for Wideband Space-time Wireless Channels Using Channel State Information

    Microsoft Academic Search

    Eko N. Onggosanusi; Barry D. Van Veen; Akbar M. Sayeed

    2003-01-01

    An orthogonal decomposition of a general wideband space-time multipath channel is derived assuming antenna arrays at both the transmitter and receiver. Knowledge of channel state information is assumed at both the transmitter and receiver. The decomposition provides a framework for efficiently managingthe degrees of freedom in the space-time channel to optimize any combination of bit-error rate and throughput in single-user

  4. Efficient signaling schemes for wideband space-time wireless channels using channel state information

    Microsoft Academic Search

    Eko N. Onggosanusi; Akbar M. Sayeed; Barry D. Van Veen

    2003-01-01

    An orthogonal decomposition of a general wideband space-time frequency selective channel is derived assuming antenna arrays at both the transmitter and receiver. Knowledge of channel state information is assumed at both the transmitter and receiver. The decomposition provides a framework for efficiently managing the degrees of freedom in the space-time channel to optimize any combination of bit-error rate and throughput

  5. Design and Measurements of Integrated Microstrip Log Periodic Antenna for Switched Narrowband and Ultra wideband Applications

    Microsoft Academic Search

    Sathyaveer Prasad; Kamtala Venkat Ramana Prasad

    Recent developments in radio engineering have thrown several challenges to the antenna designers (1). Some of these challenges are antenna miniaturization, simultaneous\\/switched multi-band operation of antenna, highly efficient, robust and reliable antenna, etc. One such development in radio engineering is the evolution of the concept of cognitive radio (2-4).A cognitive radio is a wireless transponder that not only senses the

  6. Novel compact bow-tie slot antennas for ultra-wideband applications

    Microsoft Academic Search

    Liang Zhou; Shaobin Liu; Yu Chen

    2010-01-01

    The increase of mobile applications requires antennas ever smaller in form factor. In this paper, three kinds of bow-tie slot antennas have been proposed for ultra-wide band (UWB) applications in the 3.1-10.6 GHz band including full-size, half-size and half-size antennas with a band notch. The half-size antenna with dimensions of 30×29 mm2 is proposed by halving the full-size symmetrical antenna.

  7. 4308 IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS, VOL. 6, NO. 12, DECEMBER 2007 Joint Scale-Lag Diversity in Wideband Mobile

    E-print Network

    Schniter, Philip

    -Lag Diversity in Wideband Mobile Direct Sequence Spread Spectrum Systems Adam R. Margetts, Member, IEEE, Philip of mobility on a wideband direct sequence spread spectrum (DSSS) communication system, and study a scale

  8. ECO: AN ULTRA-COMPACT LOW-POWER WIRELESS SENSOR NODE FOR REAL-TIME MOTION MONITORING

    E-print Network

    Shinozuka, Masanobu

    ECO: AN ULTRA-COMPACT LOW-POWER WIRELESS SENSOR NODE FOR REAL-TIME MOTION MONITORING Chulsung Park 92697-2625 USA {chulsung, jinfengl, phchou}@uci.edu ABSTRACT Eco is an ultra-compact wireless sensor node. Only 648 mm3 in volume and weighing under 1.6 grams, Eco was initially designed to monitor

  9. The propagation and scattering characteristics of a forest as measured by coherent ultra-wideband foliage penetration

    NASA Astrophysics Data System (ADS)

    Gwynne, John Scott

    Coherent polarimetric synthetic aperture radar (SAR) measurements of a central Ohio forest have been collected, and it is the objective of this research to document and analyze the results. The foliage data presented in this dissertation are unique in several aspects. Primarily, the data are Ultra-Wideband (UWB) in that the bandwidth (200-1600MHz) divided by center frequency is at least 25% and are of a wavelength selected to penetrate the forest canopy. Data of this bandwidth or resolution offer the opportunity to see for the first time at these frequencies scattering components such as branches, tree trunks, and ground-tree interaction terms. Secondly, coherent apertures were collected by precisely moving the antennas within a well-known coordinate system leading to absolute phase calibration and to the generation of fully coherent SAR imagery. Much of the past work performed on foliage propagation and scattering does not include phase information which is crucial for predicting the performance of radars of this type. The underlying goals of this research are to identify the fundamental scattering mechanisms associated with the forest backscatter at these frequencies and to assess UWB usage for the concealed target detection and identification problems. To this end, methods are developed to analyze the above measurements and extract modeling parameters such as the propagation loss, phase defect, and backscatter per unit area (sigmasp{o}). The analysis of these data provide the insight needed to statistically model the forest in both forward scatter and backscatter and to determine the ability of these UWB frequencies to penetrate the forest canopy.

  10. Short range, ultra-wideband radar with high resolution swept range gate

    DOEpatents

    McEwan, T.E.

    1998-05-26

    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.

  11. Short range, ultra-wideband radar with high resolution swept range gate

    DOEpatents

    McEwan, Thomas E. (Livermore, CA)

    1998-05-26

    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.

  12. A Wideband Wireless Neural Stimulation Platform for High-Density Microelectrode Arrays

    Microsoft Academic Search

    Frank B. Myers; Jim A. Simpson; Maysam Ghovanloo

    2006-01-01

    We describe a system that allows researchers to control an implantable neural microstimulator from a PC via a USB 2.0 interface and a novel dual-carrier wireless link, which provides separate data and power transmission. Our wireless stimulator, Interestim-2B (IS-2B), is a modular device capable of generating controlled-current stimulation pulse trains across 32 sites per module with support for a variety

  13. Wideband Phased Array & Rectenna Design and Modeling for Wireless Power Transmission 

    E-print Network

    Hansen, Jonathan Noel

    2012-02-14

    design features are given, and reasons for all design decisions are addressed. Design goals, fabrication techniques, and measurement results which characterize the final design are also discussed. Section 3 presents background information on array... with Hertz and Tesla in the 1800?s and concluding with today?s interest in a space solar-power satellite. Section 6 provides a theoretical discussion of rectenna and wireless power transmission technology. The wireless power transmission system as a...

  14. Tremor Acquisition System Based on UWB Wireless Sensor Network

    Microsoft Academic Search

    Gaddi Blumrosen; Moshe Uziel; Boris Rubinsky; Dana Porrat

    2010-01-01

    This work suggests to quantify and analyze tremorusing an Ultra Wide-Band (UWB) Wireless Sensor Network(WSN). WSN based on UWB technology provides a new technology for non contact tremor assessment with extremely low radiation and penetration through walls. Tremor is the target symptom in the treatment of many neurological disorders such as Parkinson's disease (PD), midbrain tremor, essential tremor (ET) and

  15. Energy Efficient Routing Protocol for Wireless Sensor Networks with Ultra Low Duty Cycle

    E-print Network

    Bahk, Saewoong

    protocol is inferior to the distributed one any more for WSNs. Rather, the centralized routing protocol canEnergy Efficient Routing Protocol for Wireless Sensor Networks with Ultra Low Duty Cycle Wooguil--In this paper, we propose a new centralized routing protocol named WRP that aims at maximizing the network

  16. An Ultra-Low-Power Power Management IC for Energy-Scavenged Wireless Sensor Nodes

    E-print Network

    Sanders, Seth

    925 An Ultra-Low-Power Power Management IC for Energy-Scavenged Wireless Sensor Nodes Michael D less power and are becoming smaller as this technology matures. Scavenged- power sensor nodes are now a reality with modern processor, sensor and radio technology [1], [2]. The efficiency of the scavenger

  17. An Ultra Low Cost Wireless Communications Laboratory for Education and Research

    ERIC Educational Resources Information Center

    Linn, Y.

    2012-01-01

    This paper presents an ultra-low-cost wireless communications laboratory that is based on a commercial off-the-shelf field programmable gate array (FPGA) development board that is both inexpensive and available worldwide. The total cost of the laboratory is under USD $200, but it includes complete transmission, channel emulation, reception…

  18. Hardware Aware Optimization of an Ultra Low Power UWB Communication System

    Microsoft Academic Search

    Florian Troesch; Christoph Steiner; Thomas Zasowski; Thomas Burger; Armin Wittneben

    2007-01-01

    A wireless body area network with an average throughput of 500 kbps based on ultra-wideband pulse position modulation is considered. For a long battery autonomy a hardware aware system optimization with respect to the specific applications at hand is essential. A key feature to achieve power savings is low duty cycle signaling, and its effectiveness when combined with burst-wise transmission

  19. Development of the wireless ultra-miniaturized inertial measurement unit WB-4: preliminary performance evaluation.

    PubMed

    Lin, Zhuohua; Zecca, Massimiliano; Sessa, Salvatore; Bartolomeo, Luca; Ishii, Hiroyuki; Takanishi, Atsuo

    2011-01-01

    This paper presents the preliminary performance evaluation of our new wireless ultra-miniaturized inertial measurement unit (IMU) WB-4 by compared with the Vicon motion capture system. The WB-4 IMU primarily contains a mother board for motion sensing, a Bluetooth module for wireless data transmission with PC, and a Li-Polymer battery for power supply. The mother board is provided with a microcontroller and 9-axis inertial sensors (miniaturized MEMS accelerometer, gyroscope and magnetometer) to measure orientation. A quaternion-based extended Kalman filter (EKF) integrated with an R-Adaptive algorithm for automatic estimation of the measurement covariance matrix is implemented for the sensor fusion to retrieve the attitude. The experimental results showed that the wireless ultra-miniaturized WB-4 IMU could provide high accuracy performance at the angles of roll and pitch. The yaw angle which has reasonable performance needs to be further evaluated. PMID:22255931

  20. Design of CMOS integrated frequency synthesizers for ultra-wideband wireless communications systems 

    E-print Network

    Tong, Haitao

    2009-05-15

    phase noise is ¬120 dBc at 3 MHz o?set. Compared with existing phase shift LC QVCOs, the proposed CSD¬QVCO presents better phase noise and power e?ciency. Finally, a novel injection locking frequency divider (ILFD) is presented. Im¬plemented with three...

  1. Joint Time/Frequency Analysis and Design of Spiral Antennas and Arrays for Ultra-Wideband Applications

    NASA Astrophysics Data System (ADS)

    Elmansouri, Mohamed Ali

    Ultra-wideband (UWB) systems transmit and receive extremely short pulses, permitting the corresponding antennas to distort their shape. Thus the design of an antenna for a UWB system plays an important role for the reliability and quality of communication. A UWB antenna design coalesces both the determination of conventional frequency domain parameters and the analysis of time domain response into a single overarching system requirement. While the former is needed to ensure system's sensitivity, the later is critical to minimize pulse distortion. Well-designed spiral antennas are known for their almost frequency independent characteristics; thus they are viable candidates for UWB systems from the frequency-domain side. However, due to their fundamental principles of operation, they are dispersive and arguments were made they should not be used for pulsed UWB applications (time-domain side). The presented research unequivocally proves that spiral antennas and various derivatives thereof, including arrays, can be excellent candidates for multi-functional time/frequency domain systems. A complete framework for joint frequency and time domain characterization of planar spiral antennas in UWB communication systems is developed first. By utilizing theory, simulations, and experiments, all essential to the analysis frameworks, the various hypotheses are comprehensively treated and relevant conclusions are established. The dispersion and pulse distortion of the conventional spiral antennas are characterized in the radiation and system modes and conclusions regarding the effects of geometrical parameters such as number of arms, mode of operations, etc., on time- and frequency-domain performance are derived for the first time. A method based on controlling the spiral's growth rate and input pulse shape is demonstrated as an effective approach to reduce the pulse distortion. Theoretical pre-distortion compensation method based on a frequency-dependent delay removal technique is employed and performance enhancement of spiral antennas as pulse radiators is successfully demonstrated. A novel spiral antenna topology, named combined power spiral, is derived from first principles to have simultaneously excellent time- and frequency-domain performances without any auxiliary hardware and/or pre-distortion compensation. The role of the reflective cavity backing on the performance of spiral antennas in time and frequency domains is investigated in order to achieve an efficient unidirectional UWB radiation. Resistively-loaded cavity-backed spirals are designed as a compromise for achieving simultaneously good time and frequency domain performances while maintaining high efficiency over the most of operating bandwidth. The lens loading approach is used as a way to further improve the spiral's gain and reduce the amplitude distortion associated with a typical communication channel. UWB spiral arrays based on the derived good time/frequency two- and four-arm spiral antennas are developed and analyzed in time and frequency domains. Multi-mode capabilities of four-arm spirals are used to engineer a dual-circularly polarized array embodiment. To make these arrays practically more desirable, novel feeding scheme which significantly reduces the beamformer complexity is proposed. Time and frequency scanning capabilities and the advantages of the proposed arrays for UWB communications are also discussed. The results of this thesis can pave the way for the use of spiral antennas in many non-traditional, for spiral antennas, applications across commercial and military sectors.

  2. Stochastic UWB wireless channel modeling and estimation from received signal measurements

    Microsoft Academic Search

    Yanyan Li; Mohammed Olama; Seddik Djouadi; Aly Fathy; Teja Kuruganti

    2009-01-01

    In this paper, stochastic differential equations (SDEs) are used to model ultra-wideband (UWB) indoor channels. We show that the impulse responses for time-varying wireless channels can be approximated in a mean square sense as close as desired by impulse responses that can be realized by SDEs. The Expected Maximization and Extended Kalman Filter are employed to recursively identify and estimate

  3. Wireless power transfer based on magnetic metamaterials consisting of assembled ultra-subwavelength meta-atoms

    NASA Astrophysics Data System (ADS)

    Wu, Q.; Li, Y. H.; Gao, N.; Yang, F.; Chen, Y. Q.; Fang, K.; Zhang, Y. W.; Chen, H.

    2015-03-01

    In this letter, a potential way to transfer power wirelessly based on magnetic metamaterials (MMs) assembled by ultra-subwavelength meta-atoms is proposed. Frequency-domain simulation and experiments are performed for accurately obtaining effective permeability of magnetic metamaterials. The results demonstrate that MMs possess great power for enhancing the wireless power transfer efficiency between two non-resonant coils. Further investigations on the magnetic-field distribution demonstrate that a large-area flattened magnetic field in near range can be effectively realized, exhibiting great flexibility in assembling.

  4. MAC Design for Supporting Ultra Low Duty Cycle in Wireless Sensor Networks1 *Wooguil PakO

    E-print Network

    Bahk, Saewoong

    MAC Design for Supporting Ultra Low Duty Cycle in Wireless Sensor Networks1 *Wooguil PakO , *Hyuk. In general, sensor medium access control (MAC) protocols reduce duty cycle to achieve longer life time.1%). Our proposed U-MAC (Ultra low duty cycle MAC) protocol targets achieving low energy consumption under

  5. Ultra-Wide Bandwidth Signal Propagation for Indoor Wireless Communications

    Microsoft Academic Search

    Moe Z. Win; Robert A. Scholtz; Mark A. Barnes

    1997-01-01

    An ultra-wide bandwidth (UWB) signal propagation experiment is performed in a typical modern office building in order to characterize the UWB signal propagation channel. The bandwidth of the signal used in this experiment is in excess of one GHz. The robustness of the WVB signal to fades is quantified through histogram and cumulative distribution of the received energy in various

  6. A Small UWB Antenna for Wireless USB

    Microsoft Academic Search

    Terence S. P. See; Zhi Ning Chen

    2007-01-01

    A printed ultra-wideband (UWB) antenna operating within a frequency range of 3.1-5 GHz is proposed for wireless USB dongle applications. The antenna consists of a triangular radiating element with a notch at the center and an L-shaped strip extended from the end of the radiator to reduce the antenna size. The ground plane is etched on the reverse side of

  7. 1 2007 Raj JainICC Tutorial, June 24, 2007 Next Generation Wireless Technologies:Next Generation Wireless Technologies

    E-print Network

    Jain, Raj

    . Ultra Wideband3. Ultra Wideband ! Ultra-Wideband: How it works ! FCC Rules on UWB ! Advantages of UWB ! Direct sequence (DS-UWB) ! Multi-Band OFDM ! Applications of UWB ! UWB Products #12;6 ©2007 Raj Jain Wideband 4. High Throughput WiFi: 802.11n 5. WiMAX Overview 6. WiMAX Technical Details 7. Other Competing

  8. Accurate indoor wireless location with IR UWB systems a performance evaluation of joint receiver structures and TOA based mechanism

    Microsoft Academic Search

    Angela Hernandez; Ruben Badorrey; Juan Choliz; Ignacio Alastruey; Antonio Valdovinos

    2008-01-01

    Impulse radio (IR) ultra wide-band (UWB) is one of the most promising wireless technologies to develop both indoor and outdoor location and tracking applications. Due to its high bandwidth and short duration pulses, UWB potentially allows a great accuracy in distance measurements based on time of arrival (TOA) estimations. The main objective of this paper is to compare and to

  9. A 250 MHz 14 dB-NF 73 dB-Gain 82 dB-DR Analog Baseband Chain With Digital-Assisted DC-Offset Calibration for Ultra-Wideband

    Microsoft Academic Search

    Horng-Yuan Shih; Chien-Nan Kuo; Wei-Hsien Chen; Tzu-Yi Yang; Kai-Chenug Juang

    2010-01-01

    A 250 MHz analog baseband chain for ultra-wideband was implemented in a 1.2 V 0.13 ¿ m CMOS process. The chip has an active area of 0.8 mm2. In the analog baseband, PGAs and filters are carried out by current-mode amplifiers to achieve wide bandwidth and wide dynamic range of gain, as well as low noise and high linearity. Besides,

  10. Small UWB Antennas for Wireless USB Dongle Attached to Laptop Computer

    Microsoft Academic Search

    Zhi Ning Chen; T. S. P. See

    2007-01-01

    This paper investigates the application of a small ultra-wideband (UWB) antenna with a reduced ground-plane effect in a wireless USB dongle, which is attached to a laptop computer. The antenna is printed onto a piece of PCB and embedded into a wireless universal serial bus (USB) dongle. The radiator may be co-planar or perpendicular to the PCB. The impedance and

  11. Pulse Shaping, Modulation and Spectrum Shaping for UWB Wireless Communications and the Effects on Interference for Single and Multiband Transmission of UWB Signals

    Microsoft Academic Search

    Michael Sablatash

    2006-01-01

    This paper focuses on pulse shaping, modulation techniques, randomization by pseudo noise (PN) and other sequences, and power spectral density (PSD) shaping of ultra wideband (UWB) wireless communication signals and their effects on interference into and by other communication signals. The evolution of techniques proposed for these, and implementations based on research and development since the early 1990's, to those

  12. An architecture for wireless simulation in NS2 applied to impulse-radio ultra-wide band networks

    Microsoft Academic Search

    Ruben Merz; Jean-yves Le Boudec; Joerg Widmer

    2007-01-01

    We present an architecture for implementing a wireless phys- ical layer in a packet-based network simulator. We integrate this architecture in the popular ns-2 network simulator and use it to implement an impulse-radio ultra-wide band (IR- UWB) physical layer. Contrary to the current wireless phys- ical layer implementation of ns-2, in our case a packet is fully received by our

  13. Channel Analysis and Estimation and Compensation of Doppler Shift in Underwater Acoustic Communication and Mitigation of IFI, ISI in Ultra-wideband Radio

    NASA Astrophysics Data System (ADS)

    Ahmed, Sadia

    Water occupies three fourth of earth's surface. The remaining one fourth is land. Although human habitats reside on land, there is no denying of the vital connection between land and water. The future sustainability of human species on this planet depends on wise utilization of all available resources, including that provided by the vast water world. Therefore, it is imperative to explore, understand, and define this massive, varying, and in many areas, unexplored water domain. The water domain exploration and data collection can be conducted using manned or unmanned vehicles, as allowed by the water environment. This dissertation addresses three of the key difficulties that occur during underwater acoustic communication among manned and/or unmanned vehicles and proposes feasible solutions to resolve those difficulties. The focus and the contributions of this research involve the following perspectives: 1) Representation of Underwater Acoustic Communication (UAC) Channels: Providing a comprehensive classification and representation of the underwater acoustic communication channel based on the channel environment. 2) Estimation and Compensation of Doppler Shift: Providing compensation algorithm to mitigate varying Doppler shift effect over subcarriers in UAC Orthogonal Frequency Division Multiplexing (OFDM) systems. 3) Mitigation of Inter-symbol Interference (ISI): Providing feasible solution to long delay spread causing ISI in Ultra-wideband channels.

  14. Harmonia: Wideband Spreading for Accurate Indoor RF Localization

    E-print Network

    Dutta, Prabal

    Radio-frequency localization; Time difference of arrival; Multipath; Ultra-wideband; Software-defined radio; Band stitching 1. INTRODUCTION Ultra-wideband (UWB) RF localization systems have been shown stitching, a technique that sweeps a highly tunable narrowband radio across a wide frequency range

  15. IEEE International Conference on Ultra-Wideband, Zurich, September 2005 Abstract--In this paper, we analyze the achievable location

    E-print Network

    services in the 3.1-10.6GHz band such as the wireless local area network (WLAN) standard IEEE802.11a short transmit pulses are necessary in a multi-path radio frequency channel to maintain an acceptable accuracy of the pulse arrival time. I. INTRODUCTION An application utilizing the radio frequency (RF

  16. Design of a 3.1-4.8 GHZ RF front-end for an ultra wideband receiver 

    E-print Network

    Sharma, Pushkar

    2006-08-16

    of mobility and portability, there has been a drive to eliminate bulky cables especially when many such devices are interconnected. This demands high-bandwidth short-range Wireless Personal Area Network (WPAN). Peak data rate of 1Mbps in Bluetooth...

  17. An ultra-wideband high-dynamic range GPR for detecting buried people after collapse of buildings

    Microsoft Academic Search

    Gilberto Grazzini; Massimiliano Pieraccini; Filippo Parrini; Alessandro Spinetti; Giovanni Macaluso; Devis Dei; Carlo Atzeni

    2010-01-01

    An ultra wide band high dynamic range GPR radar - has been tested for buried victims detection. After a building collapse, for example due to an earthquake, the priority of search and rescue teams is to localize people trapped under debris. Several tools are available to help the detection of buried humans, such as micro-cameras, high sensitivity microphones, and so

  18. Ultra wideband (0.5–16?kHz) MR elastography for robust shear viscoelasticity model identification

    NASA Astrophysics Data System (ADS)

    Liu, Yifei; Yasar, Temel K.; Royston, Thomas J.

    2014-12-01

    Changes in the viscoelastic parameters of soft biological tissues often correlate with progression of disease, trauma or injury, and response to treatment. Identifying the most appropriate viscoelastic model, then estimating and monitoring the corresponding parameters of that model can improve insight into the underlying tissue structural changes. MR Elastography (MRE) provides a quantitative method of measuring tissue viscoelasticity. In a previous study by the authors (Yasar et al 2013 Magn. Reson. Med. 70 479–89), a silicone-based phantom material was examined over the frequency range of 200?Hz–7.75?kHz using MRE, an unprecedented bandwidth at that time. Six viscoelastic models including four integer order models and two fractional order models, were fit to the wideband viscoelastic data (measured storage and loss moduli as a function of frequency). The ‘fractional Voigt’ model (spring and springpot in parallel) exhibited the best fit and was even able to fit the entire frequency band well when it was identified based only on a small portion of the band. This paper is an extension of that study with a wider frequency range from 500?Hz to 16?kHz. Furthermore, more fractional order viscoelastic models are added to the comparison pool. It is found that added complexity of the viscoelastic model provides only marginal improvement over the ‘fractional Voigt’ model. And, again, the fractional order models show significant improvement over integer order viscoelastic models that have as many or more fitting parameters.

  19. UWB radio module design for wireless sensor networks

    Microsoft Academic Search

    Majid Baghaei Nejad; Meigen Shen; Tero Koivisto; Teemu Peltonen; Esa Tjukanoff; Hannu Tenhunen; Li-Rong Zheng

    2007-01-01

    In this paper, we describe an impulse-based ultra wideband (UWB) radio system for wireless sensor network (WSN) applications.\\u000a Different architectures have been studied for base station and sensor nodes. The base station node uses coherent UWB architecture\\u000a because of the high performance and good sensitivity requirements. However, to meet complexity, power and cost constraints,\\u000a the sensor module uses a novel

  20. An Efficient Simulation Technology for Characterizing the Ultra-Wide Band Signal Propagation in a Wireless Body Area Network

    Microsoft Academic Search

    V. P. Bui; X. C. Wei; E. P. Li

    2010-01-01

    This paper presents an efficient simulation technology to characterize the Ultra-Wide Band signal propagation between the antennas in close proximity to a human body, where the human body works as a Wireless Body Area Network. The first technique is the hybrid Method of Moments and asymptotic Physical Optics in which the formulation is extended for modeling the dielectric body. The

  1. Design and optimization of an ultra wideband and compact microwave antenna for radiometric monitoring of brain temperature.

    PubMed

    Rodrigues, Dario B; Maccarini, Paolo F; Salahi, Sara; Oliveira, Tiago R; Pereira, Pedro J S; Limao-Vieira, Paulo; Snow, Brent W; Reudink, Doug; Stauffer, Paul R

    2014-07-01

    We present the modeling efforts on antenna design and frequency selection to monitor brain temperature during prolonged surgery using noninvasive microwave radiometry. A tapered log-spiral antenna design is chosen for its wideband characteristics that allow higher power collection from deep brain. Parametric analysis with the software HFSS is used to optimize antenna performance for deep brain temperature sensing. Radiometric antenna efficiency (?) is evaluated in terms of the ratio of power collected from brain to total power received by the antenna. Anatomical information extracted from several adult computed tomography scans is used to establish design parameters for constructing an accurate layered 3-D tissue phantom. This head phantom includes separate brain and scalp regions, with tissue equivalent liquids circulating at independent temperatures on either side of an intact skull. The optimized frequency band is 1.1-1.6 GHz producing an average antenna efficiency of 50.3% from a two turn log-spiral antenna. The entire sensor package is contained in a lightweight and low-profile 2.8 cm diameter by 1.5 cm high assembly that can be held in place over the skin with an electromagnetic interference shielding adhesive patch. The calculated radiometric equivalent brain temperature tracks within 0.4 °C of the measured brain phantom temperature when the brain phantom is lowered 10 °C and then returned to the original temperature (37 °C) over a 4.6-h experiment. The numerical and experimental results demonstrate that the optimized 2.5-cm log-spiral antenna is well suited for the noninvasive radiometric sensing of deep brain temperature. PMID:24759979

  2. Design and optimization of an ultra-wideband and compact microwave antenna for radiometric monitoring of brain temperature

    PubMed Central

    Maccarini, Paolo F.; Salahi, Sara; Oliveira, Tiago R.; Pereira, Pedro J. S.; Limão-Vieira, Paulo; Snow, Brent W.; Reudink, Doug; Stauffer, Paul R.

    2014-01-01

    We present the modeling efforts on antenna design and frequency selection to monitor brain temperature during prolonged surgery using non-invasive microwave radiometry. A tapered log-spiral antenna design is chosen for its wideband characteristics that allow higher power collection from deep brain. Parametric analysis with HFSS is used to optimize antenna performance for deep brain temperature sensing. Radiometric antenna efficiency (?) is evaluated in terms of the ratio of power collected from brain to total power received by the antenna. Anatomical information extracted from several adult computed tomography (CT) scans is used to establish design parameters for constructing an accurate layered 3D tissue phantom. This head phantom includes separate brain and scalp regions, with tissue equivalent liquids circulating at independent temperatures on either side of an intact skull. The optimized frequency band is 1.1–1.6 GHz producing an average antenna efficiency of 50.3% from a 2 turn log-spiral antenna. The entire sensor package is contained in a lightweight and low profile 2.8 cm diameter by 1.5 cm high assembly that can be held in place over the skin with an electromagnetic interference (EMI) shielding adhesive patch. The calculated radiometric equivalent brain temperature tracks within 0.4°C of measured brain phantom temperature when the brain phantom is lowered 10°C and then returned to original temperature (37°C) over a 4.6-hour experiment. The numerical and experimental results demonstrate that the optimized 2.5 cm log-spiral antenna is well suited for the non-invasive radiometric sensing of deep brain temperature. PMID:24759979

  3. Real-time sub-carrier Adaptive Modulation and Coding in wideband Orthogonal Frequency Division Multiplexing wireless systems

    E-print Network

    Edalat, Farinaz, 1979-

    2008-01-01

    The increasing demand for high speed wireless connectivity at low cost proposes new challenges for communication systems designers to implement solutions that increase the data rate by utilizing the limited radio resources ...

  4. Production Test Methods for Measuring 'Out-of-Band' Interference of Ultra Wide Band (UWB) Devices

    Microsoft Academic Search

    Soumendu Bhattacharya; Abhijit Chatterjee

    2005-01-01

    The recent increase in demand within the wireless user community for short-range, very high rate data transmission (data, video) devices has spurred the growth of a new generation of 4G devices, viz. ultra-wideband (UWB). Due to its wide band of operation (3.1-10.6GHz) and non-conventional transmit\\/receive scheme (using short-duration, narrow baseband pulses), spectral power leakage to outside frequency bands causes interference

  5. Ultra-broadband indoor optical wireless communication system with multimode fiber.

    PubMed

    Wang, Ke; Nirmalathas, Ampalavanapillai; Lim, Christina; Skafidas, Efstratios

    2012-05-01

    In this paper we experimentally demonstrate an ultra-broadband indoor full-duplex WDM optical wireless communication system with multimode fiber. The multimode fiber is used because it is employed in most of the already installed in-building fiber distribution networks. Simultaneous error-free (BER<10(-9)) transmission of 4×12.5 Gbps downlink and 800 Mbps uplink has been successfully demonstrated. The experimental results show that, although the use of multimode fiber will induce ~2.4 cm reduction in the maximum error-free beam footprint in the downlink, the bit rate of the uplink can be much higher compared to the system with single-mode fiber. PMID:22555722

  6. Eco: an ultra-compact low-power wireless sensor node for real-time motion monitoring

    Microsoft Academic Search

    Jinfeng Liu; Pai H. Chou

    2005-01-01

    Eco is an ultra-compact wireless sensor node. Only 648 mm, in volume and weighing under 1.6 grams, Eco was initially designed to monitor the spontaneous motion of preterm infants over 2.4GHz radio links at the maximum data rate of 1Mbps. The compact form factor and low power consumption also make Eco nodes highly suitable for many other applications, including medicine,

  7. UWB High Data-Rate Wireless Communication System Base on MultiPulse Position Modulation

    Microsoft Academic Search

    Wang Ye-qiu; Lu Ying-hua; Xu Yong; He Peng-fei; Zhang Na

    2006-01-01

    In this paper, we propose a new modulation scheme called L-ary multi-pulse position modulation (L-ary MPPM) for ultra-wideband (UWB) high data-rate wireless communication systems. MPPM is an improved pulse position modulation(PPM) by employing multiple pulses and constant weight code to provide a better system performance with comparison with L-ary single-pulse position modulation (SPPM). The error probability and maximum reliable communication

  8. SWIFT: A Narrowband-Friendly Cognitive Wideband Network

    E-print Network

    Sodini, Charles

    2008-08-17

    Wideband technologies in the unlicensed spectrum can satisfy the ever-increasing demands for wireless bandwidth created by emerging rich media applications. The key challenge for such systems, however, is to allow narrowband ...

  9. IEEE JOURNAL OF SOLID-STATE CIRCUITS, VOL. 49, NO. 5, MAY 2014 1223 Nanostructured CMOS Wireless Ultra-Wideband

    E-print Network

    Genov, Roman

    fabricated in a 0.13 µm standard CMOS technology has been validated in prostate cancer synthetic DNA such as DNA, messenger RNA (mRNA), and micro-RNA have recently been exploited for the diagnosis, prognosis

  10. Nanostructured CMOS Wireless Ultra-Wideband Label-free DNA Analysis SoC H. M. Jafari1

    E-print Network

    Genov, Roman

    H CTAT PTAT ×48 PID SRAM WE WE PCR SRAM MADC IREF IIN SIGNAL GENERATOR CE RE CLK 1.2 VIBIAS VBIAS CCII CLOCK GEN BIAS COMPLETE SYSTEM SIGNAL GENERATORSRAM HEATER PWM MULTIPLICATION COEFFICENTS SRAM GLOBAL

  11. A 128Channel 6 mW Wireless Neural Recording IC With Spike Feature Extraction and UWB Transmitter

    Microsoft Academic Search

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

    2009-01-01

    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

  12. Circuit-Switching Physical Layer Based on Time-Frequency Coding for MultiBand UWB Wireless Networks

    Microsoft Academic Search

    Vasily Aristarkhov

    2008-01-01

    The article describes physical layer (PHY) for high data-rate self-organized wireless networks based on the Ultra Wideband (UWB) technology with frequency band [3.1 - 10.6] GHz. The developed transceiver scheme has wide range adaptation features and cross-layer elements based on convergence of maximum likelihood sequence estimation (MLSE) equalizer and frequency hopping (FH). Circuit switching technology for multiply access and data

  13. High-performance signal acquisition algorithms for wireless communications receivers

    E-print Network

    Shi, Kai

    2006-10-30

    schemes together with their performance analysis and comparisons with existing state-of-the- art results are introduced. The design effort is first focused on narrowband systems, and then on wideband and ultra wideband systems. For single carrier modulated...

  14. Ultra Low Power Small Size RF Transceiver Design for Wireless Sensor Networks

    Microsoft Academic Search

    Abid Ali Minhas; Muhammad Yasir Faheem; Muhammad Basit Azeem

    2011-01-01

    Some transceivers operate in the industrial, scientific and medical (ISM) band. Usually Wireless sensor nodes are mostly battery operated and in many applications they are placed unattended. It requires designing both hardware and software that consume very low power during the operations. Current size of the wireless sensor node is in the order of millimeter. Scientists and engineers are trying

  15. A wideband deflected reflection based on multiple resonances

    NASA Astrophysics Data System (ADS)

    Chen, Hongya; Ma, Hua; Wang, Jiafu; Qu, Shaobo; Li, Yongfeng; Wang, Jun; Yan, Mingbao; Pang, Yongqiang

    2015-05-01

    We propose to realize wideband deflected reflection in microwave regime through multiple resonances. A wideband deflected reflection of a phase gradient metasurface is designed using a double-head arrow structure, which has demonstrated an ultra-wideband cross-polarized reflection caused by multiple electric and magnetic resonances. The wideband effect benefits from the wideband cross-polarized reflection and flexible phase modulation of the double-head arrow structure. Simulated and experimental results agree well with theoretical predictions. Furthermore, relative bandwidths of deflected reflection reach to 71 % for both x- and y-polarized waves under normal incidence. Our method of expansion bandwidth may pave the way in many practical applications, such as RCS reduction, stealth surfaces.

  16. A wideband deflected reflection based on multiple resonances

    NASA Astrophysics Data System (ADS)

    Chen, Hongya; Ma, Hua; Wang, Jiafu; Qu, Shaobo; Li, Yongfeng; Wang, Jun; Yan, Mingbao; Pang, Yongqiang

    2015-07-01

    We propose to realize wideband deflected reflection in microwave regime through multiple resonances. A wideband deflected reflection of a phase gradient metasurface is designed using a double-head arrow structure, which has demonstrated an ultra-wideband cross-polarized reflection caused by multiple electric and magnetic resonances. The wideband effect benefits from the wideband cross-polarized reflection and flexible phase modulation of the double-head arrow structure. Simulated and experimental results agree well with theoretical predictions. Furthermore, relative bandwidths of deflected reflection reach to 71 % for both x- and y-polarized waves under normal incidence. Our method of expansion bandwidth may pave the way in many practical applications, such as RCS reduction, stealth surfaces.

  17. Micromachined wide-band lithium-niobate electrooptic Modulators

    Microsoft Academic Search

    Yongqiang Shi

    2006-01-01

    We present our detailed study of a micromachined substrate approach for a wide-band lithium-niobate modulator and other ultra-wideband RF interconnection applications. Resonant substrate mode coupling often results in large RF loss that affects the frequency performance in LiNbO3 modulators. Using the micromachining approach, we demonstrated significantly reduced resonant mode coupling loss in LiNbO3 modulator electrodes. In this paper, the effects

  18. Wide-band Microwave Bandpass Filters With Hybrid Rings

    Microsoft Academic Search

    Roberto Gomez-Garcia

    2007-01-01

    A new type of sharp, high-rejection microwave planar bandpass Alter based on signal-interference techniques is reported. The proposed topology uses, for the first time, hybrid-ring couplers operating as transversal altering sections (TFSs). High-selectivity ultra-wideband (UWB) or flat in-band group-delay wide-band bandpass Altering responses are achievable with this TFS. Design equations and guidelines for the described hybrid-ring-based TFS are also provided.

  19. Design of indoor communication infrastructure for ultra-high capacity next generation wireless services

    E-print Network

    Gordon, George S. D.

    2013-11-12

    . This thesis addresses this problem through examining the design of distributed antenna systems (DAS) to support next generation high speed wireless services that require high densities of access points and must support multiple-input multiple-output (MIMO...

  20. An ultra-wideband transmit/receive module using 10 to 35 GHz six-channel microstrip multiplexers and its applications to phased-array antenna transceiver systems

    E-print Network

    Hong, Seung Pyo

    2006-10-30

    as applications of the MMIC amplifiers. In addition, a multi-frequency antenna has been developed. A single-feed triple frequency microstrip patch antenna is presented as an answer to the recent demand for multi-function systems in the wireless communications...

  1. GaAs wideband low noise amplifier design for breast cancer detection system

    Microsoft Academic Search

    Lei Yan; Viktor Krozer; S. Delcourt; V. Zhurbenko; T. K. Johansen; Chenhui Jiang

    2009-01-01

    Modern wideband systems require low-noise receivers with bandwidth approaching 10 GHz. This paper presents ultra-wideband stable low-noise amplifier MMIC with cascode and source follower buffer configuration using GaAs technology. Source degeneration, gate and shunt peaking inductors are used to explore simultaneous wideband noise optimization and input power matching requirement. The low-noise amplifier circuit operates across a band of 0.3 to

  2. Modified Printed Bow-Tie Antenna For C And X Bands Wideband Phased Array Systems

    E-print Network

    Elsherbeni, Atef Z.

    Printed microstrip antennas are widely used in wireless communication and phased array applicationsModified Printed Bow-Tie Antenna For C And X Bands Wideband Phased Array Systems Abdelnasser A for wideband phased array systems. The operating band of the proposed antenna simultaneously covers

  3. An oil peaking switch to drive a dipole antenna for wideband applications

    Microsoft Academic Search

    R. Pecquois; L. Pecastaing; M. Rivaletto; A. De Ferron; P. Pignolet; J. Martin; L. Caramelle; J. M. Duband; R. Vezinet

    2011-01-01

    When the load is an antenna, the High Pulsed Power (HPP) generators allow generating electromagnetic waves in the form of pulses for wideband or ultra wideband applications. In this case, the HPP generator is usually made up of a primary energy source loading a power-amplification system. A Marx generator or a Tesla transformer is classically used as a power- amplifier.

  4. Wideband phased array antennas and compact, harmonic-suppressed microstrip filters 

    E-print Network

    Tu, Wen-Hua

    2009-05-15

    Modern satellite, wireless communications, and radar systems often demand wideband performance for multi-channel and multi-function operations. Among these applications, phased array antennas play an important role. This dissertation covers two...

  5. A 3.1 to 10.6 GHz 100 Mb\\/s Pulse-Based Ultra-Wideband Radio Receiver Chipset

    Microsoft Academic Search

    F. S. Lee; R. Blazquez; B. P. Ginsburg; J. D. Powell; M. Scharfstein; D. D. Wentzloff; A. P. Chandrakasan

    2006-01-01

    A complete 3.1-10.6 GHz ultra-wide band receiver using 500 MHz-wide sub-banded binary phase shift keyed (BPSK) pulses has been specified, designed and integrated as a three chip and planar antenna solution. The system includes a custom designed 3.1-10.6 GHz planar antenna, direct-conversion RF front-end, 500 MS\\/s analog to digital converters, and a parallelized digital back-end for signal detection and demodulation.

  6. A novel darlington amplifier optimized for wideband

    Microsoft Academic Search

    Oleg V. Stukach

    2008-01-01

    A new design topology and performance for the ultra wideband Darlington amplifier is described. The amplifier configuration consists of a common-emitter transistor pair with low-pass filter. The normalized gain characteristic for the amplifier provides 1.36 multiple expansion of frequency band without degradation of the dynamic range, at VSWR and matching of input-output retaining. Expression for the optimum transfer factor was

  7. Wireless Ultra-Low Power Smart Data Acquisition System for Pressure Sensing in Medical Application

    Microsoft Academic Search

    K. Arshak; E. Jafer

    2006-01-01

    The development of a wireless sensor microsystems containing all the components of data acquisition system, such as sensors, signal-conditioning circuits, analog-digital converter, embedded microcontroller (MCU), and RF communication modules has become now the focus of attention in many biomedical applications. This paper discusses innovation circuits and system techniques for building advanced smart medical devices (SMD). Low power consumption and high

  8. An Ultra Low Power SIMD Processor for Wireless Devices , Sangwon Seo1

    E-print Network

    Kambhampati, Subbarao

    previous third generation wireless technolo- gies (3G) with a power envelope that can only increase by 2-5x intensive than current mobile video. Figure 1 presents the demands of the 3G and 4G protocols in terms-throughput requirements of these protocols. 3G protocols, such as W- CDMA, require approximately 100 Mops/mW. SODA [5] im

  9. PicoRadio Supports Ad Hoc Ultra-Low Power Wireless Networking

    Microsoft Academic Search

    Jan M. Rabaey; M. Josie Ammer; Julio Leao da Silva Jr.; Danny Patel; Shad Roundy

    2000-01-01

    Technology advances have made it conceivable to build and deploy dense wireless networks of heterogeneous nodes collecting and disseminating wide ranges of environmental data. Applications of such sensor and monitoring networks include smart homes equipped with security, identification, and personalization systems; intelligent assembly systems; warehouse inventory control; interactive learning toys; and disaster mitigation. The opportunities emerging from this technology give

  10. An Ultra-low-supply Dual-band VCO for Wireless Sensor Networks

    Microsoft Academic Search

    Bo Zhao; Yongpan Liu; Pengpeng Chen; Tao Chen; Huazhong Yang; Hui Wang

    2009-01-01

    Aggressive scaling down reduces the supply voltage of digital integrated circuits continuously. In order to realize systems-on-a-chip (SOC), analog and RF circuits should also work under the reduced voltage. For wireless sensor networks (WSN), low supply is important for communication nodes as the supply voltage must be low enough under a single solar cell as power source. Besides, the future

  11. Centralized Routing Protocol for Wireless Sensor Networks with Ultra Low Duty Cycle to Achieve Maximum Lifetime

    E-print Network

    Bahk, Saewoong

    needs no packet flooding for routing recovery and it also solves high energy consumption caused which should be solved before it is used in real network. · Packet flooding problem : Due to long packet forwarding delay and low throughput of ultra low duty cycled network, flooding can't work properly. · High

  12. Characterization of ultra-wide bandwidth wireless indoor channels: a communication-theoretic view

    Microsoft Academic Search

    Moe Z. Win; Robert A. Scholtz

    2002-01-01

    An ultra-wide bandwidth (UWB) signal propagation experiment is performed in a typical modern laboratory\\/office building. The bandwidth of the signal used in this experiment is in excess of 1 GHz, which results in a differential path delay resolution of less than a nanosecond, without special processing. Based on the experimental results, a characterization of the propagation channel from a communications

  13. Energy capture vs. correlator resources in ultra-wide bandwidth indoor wireless communications channels

    Microsoft Academic Search

    Moe Z. Win; Robert A. Scholtz

    1997-01-01

    The results of an ultra-wide bandwidth (UWB) signal propagation experiment performed in a typical modern office building are presented. The bandwidth of the signal used in this experiment is in excess of one GHz, which results in a multipath resolution of less than a nanosecond. The maximum likelihood (ML) detector, based on a specular multipath channel model, is derived to

  14. Broadband wireless local-area networks at millimeter waves around 60 GHz

    Microsoft Academic Search

    A. G. Siamarou

    2003-01-01

    During the past few years, research covering propagation, channel characterization, and wireless system performance has yielded a substantial knowledge of the 60 GHz channel. The unlicensed 60 GHz frequency band presents many attractive properties for wireless communications. This paper addresses some wideband propagation characteristics for broadband wireless LANs (BWLANs). Important system-design characteristics, from measured results obtained from two wideband 60

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

    Microsoft Academic Search

    Sean Victor Hum; Leonard T. Bruton

    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)

  16. A Wavelet Approach to Wideband Spectrum Sensing for Cognitive Radios

    Microsoft Academic Search

    Zhi Tian; Georgios B. Giannakis

    2006-01-01

    In cognitive radio networks, the first cognitive task preceding any form of dynamic spectrum management is the sensing and identification of spectrum holes in wireless environments. This paper develops a wavelet approach to efficient spectrum sensing of wideband channels. The signal spectrum over a wide frequency band is decomposed into elementary building blocks of subbands that are well characterized by

  17. Wideband Underwater Acoustic CDMA: Adaptive Multichannel Receiver Design

    E-print Network

    Stojanovic, Milica

    - sequence (DS) spread-spectrum modulation is considered for the future mobile underwater wireless) processing of asynchronous wideband direct-sequence CDMA signals are proposed: the symbol decision feedback communication net- works [1]. In addition to inherent multipath diversity, DS spread-spectrum provides a natural

  18. Wireless ultra-wide-band transmission prototype ASICs for low-power space and radiation applications

    NASA Astrophysics Data System (ADS)

    Gabrielli, A.; Crepaldi, M.; Demarchi, D.; Motto Ros, P.; Villani, G.

    2014-11-01

    The paper describes the design and the fabrication of a microelectronic circuit composed of a sensor, an oscillator, a modulator, a transmitter and an antenna. The chip embeds a custom radiation sensor, provided by the silicon foundry that has fabricated the prototypes, but in principle the entire system can read a general sensor, as long as a proper interface circuit is used. The natural application for this circuit is radiation monitoring but the low-power budget extends the applications to space where wireless readout circuits can be applied to any type of sensors, even if not radiation sensitive devices.

  19. An ultra-low-power 868\\/915 MHz RF transceiver for wireless sensor network applications

    Microsoft Academic Search

    R. van Langevelde; M. van Elzakker; D. van Goor; H. Termeer; J. Moss; A. J. Davie

    2009-01-01

    This paper describes an ultra-low-power RF transceiver implemented as part of a system-on-chip. The transceiver operates in the 868\\/915 MHz frequency band using binary FSK modulation at a 45 kbit\\/s data rate. It achieves -89 dBm receiver sensitivity and -6 dBm transmitter output power while consuming 1.6 mA and 1.8 mA, respectively, from a 1.2 to 1.5 V supply. It

  20. Low-noise amplifiers in wireless communications: state of the art, two new wideband all-active LNAs in SiGe-BiCMOS

    Microsoft Academic Search

    Balwant Godara; Alain Fabre

    2009-01-01

    The aim of this paper is three-fold. First, it introduces the low-noise amplifier, its relevance in modern wireless communications\\u000a receivers and the performance expected of it. Then, it presents an exhaustive review of the existing topologies, presenting\\u000a their advantages and shortcomings. And finally, it introduces a new class of LNAs, based on current conveyors, describing\\u000a the founding principle and the

  1. A low complexity wireless microbial fuel cell monitor using piezoresistive sensors and impulse-radio ultra-wide-band

    NASA Astrophysics Data System (ADS)

    Crepaldi, M.; Chiolerio, A.; Tommasi, T.; Hidalgo, D.; Canavese, G.; Stassi, S.; Demarchi, D.; Pirri, F. C.

    2013-05-01

    Microbial Fuel Cells (MFCs) are energy sources which generate electrical charge thanks to bacteria metabolism. Although functionally similar to chemical fuel cells (both including reactants and two electrodes, and anode and cathode), they have substantial advantages, e.g. 1) operation at ambient temperature and pressure; 2) use of neutral electrolytes and avoidance of expensive catalysts (e.g. platinum); 3) operation using organic wastes. An MFC can be effectively used in environments where ubiquitous networking requires the wireless monitoring of energy sources. We then report on a simple monitoring system for MFC comprising an ultra-low-power Impulse-Radio Ultra-Wide-Band Transmitter (TX) operating in the low 0-960MHz band and a nanostructured piezoresistive pressure sensor connected to a discrete component digital read-out circuit. The sensor comprises an insulating matrix of polydimethylsiloxane and nanostructured multi-branched copper microparticles as conductive filler. Applied mechanical stress induces a sample deformation that modulates the mean distance between particles, i.e. the current flow. The read-out circuit encodes pressure as a pulse rate variation, with an absolute sensitivity to the generated MFC voltage. Pulses with variable repetition frequency can encode battery health: the pressure sensor can be directly connected to the cells membrane to read excessive pressure. A prototype system comprises two MFCs connected in series to power both the UWB transmitter which consumes 40?W and the read-out circuit. The two MFC generate an open circuit voltage of 1.0+/-0.1V. Each MFC prototype has a total volume of 0.34L and is formed by two circular Poly(methyl methacrylate) (PMMA) chambers (anode and cathode) separated by a cation exchange membrane. The paper reports on the prototype and measurements towards a final solution which embeds all functionalities within a MFC cell. Our solution is conceived to provide energy sources integrating energy management and health monitoring capabilities to sensor nodes which are not connected to the energy grid.

  2. Wideband active antenna cancellation

    E-print Network

    Adaniya, Hana L

    2008-01-01

    There exists a simultaneous transmit and receive antenna system where the transmitted signal is creating wideband interference of the receiver. To resolve this interference problem, the isolation between the transmit antenna ...

  3. Wideband DS-CDMA for next-generation mobile communications systems

    Microsoft Academic Search

    Fumiyuki Adachi; Mamoru Sawahashi; Hirohito Suda

    1998-01-01

    Wideband wireless access based on direct sequence code division multiple access aimed at third-generation mobile communications systems is reviewed. W-CDMA is designed to flexibly offer wideband services which cannot be provided by present cellular systems, with various data rates as high as 2 Mb\\/s. The important concept of W-CDMA is the introduction of intercell asynchronous operation and the pilot channel

  4. A 0.13-$\\\\mu{\\\\hbox {m}}$ 1GS\\/s CMOS Discrete-Time FFT Processor for Ultra-Wideband OFDM Wireless Receivers

    Microsoft Academic Search

    Mark Lehne; Sanjay Raman

    2011-01-01

    A discrete-time (DT) fast Fourier transform (FFT) processor is presented as an architectural approach to Fourier transform processing multigigahertz of spectral bandwidth. The processor is considered with the specific application of demodu- lating orthogonal frequency-division multiplexing (OFDM) mod- ulation. The processor enables increased receiver linearity beyond that which is typically limited by the signal-to-noise-and-distortion ratio of high sample rate ADCs

  5. Channel Uncertainty in Ultra Wideband Communication Systems

    E-print Network

    Tse, David

    not have to be peaky in frequency as well. We analyze direct sequence spread spectrum (DSSS) and pulse for any number of channel paths and 2. direct sequence spread spectrum signals with continuous principle is demonstrated by comparing the channel conditions that allow duty-cycled direct-sequence spread

  6. Channel Uncertainty in Ultra Wideband Communication Systems

    E-print Network

    Southern California, University of

    modulations, M`edard and Gallager [5] show that direct sequence spread spectrum signals, when transmitted analyze direct sequence spread spectrum (DSSS) and pulse position modulation (PPM) signals, and show an infinitely wide bandwidth if they use duty cycle. At the limit of infinite bandwidth, direct sequence spread

  7. Bandwidth Scaling in Ultra Wideband Communication 1

    E-print Network

    Porrat, Dana

    of infinite bandwidth, direct sequence spread spectrum and pulse position modulation sys- tems with duty cycle modulations, Telatar and Tse [5] have shown that direct sequence spread spectrum signals, when transmitted, and the transmitted signal does not have to be peaky in frequency as well. We analyze direct sequence spread spectrum

  8. RFI suppression for ultra wideband radar

    Microsoft Academic Search

    T. Miller; L. Potter; J. McCorkle

    1997-01-01

    An estimate-and-subtract algorithm is presented for the real-time digital suppression of radio frequency interference (RFI) in ultrawideband (UWB) synthetic aperture radar (SAR) systems used for foliage- and ground-penetrating imaging. The algorithm separately processes fixed- and variable-frequency interferers. Excision of estimated targets greatly reduces bias in RFI estimates, thereby reducing target energy loss and sidelobe levels in SAR imagery. Performance is

  9. Ultra-wideband CMOS-MEMS radio

    Microsoft Academic Search

    Esa Tiiliharju; Tero Koivisto; Janne Maunu; N. Chekurovy; I. Tittoneny

    2009-01-01

    Current ultrawideband (UWB) radios have several unsolved issues in front-end performance including difficult and expensive clock synthesizer designs, and power hungry baseband functions. In fact, the expected breakthrough of the very useful UWB technology has stalled since realized high bitrate integrated radios are much too expensive in the sense that they dissipate a lot of DC power and that their

  10. Two-level threshold for RCAC (region-based call admission control) in multimedia wireless network

    Microsoft Academic Search

    Jun-Hwa Lee; Kwang-Il Lee; Mi-Ran Choi; Sang-Ha Kim

    2001-01-01

    Next generation wireless networks are expected to support multi-rate multimedia services, including wideband services, and to have smaller cell structures like micro\\/pico cells. Smaller cells increase the handoff traffic drastically and wideband services cause severe network fluctuations with their frequent handoffs. As a result, it is a challenge to provide stable QoS in wireless networks. In addition, some wideband services

  11. Wireless Tower 2 

    E-print Network

    Unknown

    2011-09-05

    the IIP3 by 3.5 to 9 dB over a 2.5–10 GHz frequency range. A comparison of measurement results with the prior published state-of-art Ultra-Wideband (UWB) LNAs shows that the proposed linearized UWB LNA achieves excellent linearity with much less power than...

  12. MPAP: virtualization architecture for heterogenous wireless APs

    Microsoft Academic Search

    Yong He; Ji Fang; Jiansong Zhang; Haichen Shen; Kun Tan; Yongguang Zhang

    2011-01-01

    This demonstration shows a novel virtualization architecture, called Multi-Purpose Access Point (MPAP), which can virtualize multiple heterogenous wireless standards based on software radio. The basic idea is to deploy a wide-band radio front-end to receive wireless signals from all wireless standards sharing the same spectrum band, and use separate software base-bands to demodulate information stream for each wireless standard. Based

  13. MPAP: virtualization architecture for heterogenous wireless APs

    Microsoft Academic Search

    Yong He; Ji Fang; Jiansong Zhang; Haicheng Shen; Kun Tan; Yongguang Zhang

    2010-01-01

    This demonstration shows a novel virtualization architecture, called Multi-Purpose Access Point (MPAP), which can virtualize multiple heterogenous wireless standards based on software radio. The basic idea is to deploy a wide-band radio front-end to receive wireless signals from all wireless standards sharing the same spectrum band, and use separate software base-bands to demodulate information stream for each wireless standard. Based

  14. 2116 IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION, VOL. 56, NO. 7, JULY 2008 [1] M. J. Ammann and Z. N. Chen, "Wideband monopole antennas for

    E-print Network

    Nam, Sangwook

    . Kumar, and K. P. Ray, "Wide-band planar monopole antennas," IEEE Trans. Antennas Propag., vol. 46, no. 2 wide band antennas," in European Microwave Conf., Oct. 4­6, 2005, vol. 3, p. 4. [20] Z. N. Chen. Ammann and Z. N. Chen, "Wideband monopole antennas for multi-band wireless systems," IEEE Antennas Propag

  15. Tunable filters using wideband elastic resonators.

    PubMed

    Kadota, Michio; Ogami, Takashi; Kimura, Tetsuya; Daimon, Katsuya

    2013-10-01

    Currently, an ultra-wideband resonator is greatly needed to realize a tunable filter with a wide tunable range, because mobile phones with multiple bands and cognitive radio systems require such tunable filters to simplify their circuits. Although tunable filters have been studied using SAW resonators, their tunable range was insufficient for the filters even when wideband SAW resonators with a bandwidth of 17% were used. Therefore, the fabrication of wider-bandwidth resonators has been attempted with the goal of realizing tunable filters with wide tunable ranges. In this study, an SH0- mode plate wave resonator in a 27.5°YX-LiNbO3 plate with an ultra-wide bandwidth of 29.1%, a high impedance ratio of 98 dB, and a high Q (Q(r) = 700 and Q(a) = 720) was realized. Two types of tunable filters were constructed using such SH0-mode resonators and capacitors. As a result, tunable ranges (bands) of 13% to 19% were obtained. The possibility of applying the SH0-mode resonator in the high-frequency gigahertz range is discussed. PMID:24081261

  16. WiseMAC: an ultra low power MAC protocol for the downlink of infrastructure wireless sensor networks

    Microsoft Academic Search

    Amre El-hoiydi; Jean-dominique Decotignie

    2004-01-01

    This paper proposes WiseMAC (Wireless Sensor MAC) for the downlink of infrastructure wireless sensor networks. WiseMAC is a novel energy efficient medium access control protocol based on synchronized preamble sampling. The trade-off between power consumption and delay is ana- lyzed, focusing on low traffic. WiseMAC is compared an- alytically with the power management protocol used in the IEEE 802.15.4 ZigBee

  17. A PVT-tolerant, ultra-low-power phase-locked loop for wireless implantable biomedical devices

    Microsoft Academic Search

    Wu-Hsin Chen; Wing-Fai Loke; Byunghoo Jung

    2011-01-01

    An ultra-low-power, low-voltage frequency synthe­ sizer designed for implantable biomedical devices is presented. Several design techniques are employed to address the issues in ultra-low voltage design, including the dynamic threshold-voltag e for a drain-switching charge pump and dual resistor-varacto r tuning for a ring-based voltage control oscillator . Moreover, three automatic calibration circuits are embedded to compensate the performance deviation

  18. Ultra-short pulse generator

    DOEpatents

    McEwan, Thomas E. (Livermore, CA)

    1993-01-01

    An inexpensive pulse generating circuit is disclosed that generates ultra-short, 200 picosecond, and high voltage 100 kW, pulses suitable for wideband radar and other wideband applications. The circuit implements a nonlinear transmission line with series inductors and variable capacitors coupled to ground made from reverse biased diodes to sharpen and increase the amplitude of a high-voltage power MOSFET driver input pulse until it causes non-destructive transit time breakdown in a final avalanche shockwave diode, which increases and sharpens the pulse even more.

  19. Ultra-short pulse generator

    DOEpatents

    McEwan, T.E.

    1993-12-28

    An inexpensive pulse generating circuit is disclosed that generates ultra-short, 200 picosecond, and high voltage 100 kW, pulses suitable for wideband radar and other wideband applications. The circuit implements a nonlinear transmission line with series inductors and variable capacitors coupled to ground made from reverse biased diodes to sharpen and increase the amplitude of a high-voltage power MOSFET driver input pulse until it causes non-destructive transit time breakdown in a final avalanche shock wave diode, which increases and sharpens the pulse even more. 5 figures.

  20. Poster abstract: wiseMAC, an ultra low power MAC protocol for the wiseNET wireless sensor network

    Microsoft Academic Search

    A. El-hoiydi; J. d. Decotignie; C. Enz; E. Le Roux

    2003-01-01

    WiseMAC is a medium access control protocol designed for the WiseNET™ wireless sensor network. It is based on CSMA and uses the preamble sampling technique to minimize the power consumed when listening to an idle medium. A unique feature of this protocol is to exploit the knowledge of the sampling schedule of its direct neighbors in order to use a

  1. Continuous wireless pressure monitoring and mapping with ultra-small passive sensors for health monitoring and critical care.

    PubMed

    Chen, Lisa Y; Tee, Benjamin C-K; Chortos, Alex L; Schwartz, Gregor; Tse, Victor; Lipomi, Darren J; Wong, H-S Philip; McConnell, Michael V; Bao, Zhenan

    2014-01-01

    Continuous monitoring of internal physiological parameters is essential for critical care patients, but currently can only be practically achieved via tethered solutions. Here we report a wireless, real-time pressure monitoring system with passive, flexible, millimetre-scale sensors, scaled down to unprecedented dimensions of 1 × 1 × 0.1 cubic millimeters. This level of dimensional scaling is enabled by novel sensor design and detection schemes, which overcome the operating frequency limits of traditional strategies and exhibit insensitivity to lossy tissue environments. We demonstrate the use of this system to capture human pulse waveforms wirelessly in real time as well as to monitor in vivo intracranial pressure continuously in proof-of-concept mice studies using sensors down to 2.5 × 2.5 × 0.1 cubic millimeters. We further introduce printable wireless sensor arrays and show their use in real-time spatial pressure mapping. Looking forward, this technology has broader applications in continuous wireless monitoring of multiple physiological parameters for biomedical research and patient care. PMID:25284074

  2. Prediction of Fast Fading Mobile Radio Channels in Wideband Communication Systems

    E-print Network

    Dong, Liang

    , TX 78712 Abstract-- The fast fading mobile radio channels place fundamental limitationsPrediction of Fast Fading Mobile Radio Channels in Wideband Communication Systems Liang Dong. Introduction The radio channel in a wireless communication system is often characterized by multipath propa

  3. Wideband optical sensing using pulse interferometry.

    PubMed

    Rosenthal, Amir; Razansky, Daniel; Ntziachristos, Vasilis

    2012-08-13

    Advances in fabrication of high-finesse optical resonators hold promise for the development of miniaturized, ultra-sensitive, wide-band optical sensors, based on resonance-shift detection. Many potential applications are foreseen for such sensors, among them highly sensitive detection in ultrasound and optoacoustic imaging. Traditionally, sensor interrogation is performed by tuning a narrow linewidth laser to the resonance wavelength. Despite the ubiquity of this method, its use has been mostly limited to lab conditions due to its vulnerability to environmental factors and the difficulty of multiplexing - a key factor in imaging applications. In this paper, we develop a new optical-resonator interrogation scheme based on wideband pulse interferometry, potentially capable of achieving high stability against environmental conditions without compromising sensitivity. Additionally, the method can enable multiplexing several sensors. The unique properties of the pulse-interferometry interrogation approach are studied theoretically and experimentally. Methods for noise reduction in the proposed scheme are presented and experimentally demonstrated, while the overall performance is validated for broadband optical detection of ultrasonic fields. The achieved sensitivity is equivalent to the theoretical limit of a 6 MHz narrow-line width laser, which is 40 times higher than what can be usually achieved by incoherent interferometry for the same optical resonator. PMID:23038542

  4. Assessment of the feasibility of an ultra-low power, wireless digital patch for the continuous ambulatory monitoring of vital signs

    PubMed Central

    Hernandez-Silveira, Miguel; Ahmed, Kamran; Ang, Su-Shin; Zandari, Fahriya; Mehta, Tinaz; Weir, Rebecca; Burdett, Alison; Toumazou, Chris; Brett, Stephen J

    2015-01-01

    Background and objectives Vital signs are usually recorded at 4–8?h intervals in hospital patients, and deterioration between measurements can have serious consequences. The primary study objective was to assess agreement between a new ultra-low power, wireless and wearable surveillance system for continuous ambulatory monitoring of vital signs and a widely used clinical vital signs monitor. The secondary objective was to examine the system's ability to automatically identify and reject invalid physiological data. Setting Single hospital centre. Participants Heart and respiratory rate were recorded over 2?h in 20 patients undergoing elective surgery and a second group of 41 patients with comorbid conditions, in the general ward. Outcome measures Primary outcome measures were limits of agreement and bias. The secondary outcome measure was proportion of data rejected. Results The digital patch provided reliable heart rate values in the majority of patients (about 80%) with normal sinus rhythm, and in the presence of abnormal ECG recordings (excluding aperiodic arrhythmias such as atrial fibrillation). The mean difference between systems was less than ±1?bpm in all patient groups studied. Although respiratory data were more frequently rejected as invalid because of the high sensitivity of impedance pneumography to motion artefacts, valid rates were reported for 50% of recordings with a mean difference of less than ±1?brpm compared with the bedside monitor. Correlation between systems was statistically significant (p<0.0001) for heart and respiratory rate, apart from respiratory rate in patients with atrial fibrillation (p=0.02). Conclusions Overall agreement between digital patch and clinical monitor was satisfactory, as was the efficacy of the system for automatic rejection of invalid data. Wireless monitoring technologies, such as the one tested, may offer clinical value when implemented as part of wider hospital systems that integrate and support existing clinical protocols and workflows. PMID:25991447

  5. IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS, VOL. 6, NO. 12, DECEMBER 2007 1 Reduced-Complexity UWB Time-Reversal Techniques and

    E-print Network

    Qiu, Robert Caiming

    reversal technique for ultra-wideband (UWB) communications. Time reversal takes advantage of rich. Index Terms-- Time reversal, ultra-wideband (UWB), autocor- relation correlation demodulation (ACD), and multiple antennas. I. INTRODUCTION STIMULATED by the FCC's move that allows UWB waveforms to overlay over

  6. A new fractal antenna for ultra wide- and multi-band applications

    Microsoft Academic Search

    Abolfazl Azari

    2011-01-01

    Ultra wideband antennas are used considerably in commercial and military telecommunication systems. A reduction in physical size and multi-band ability are very important in design of ultra wideband antenna. The use of fractal geometry in antenna design provides a good method for achieving the desired miniaturization and multi-band performances. In this paper, a compact, multi-band and broad-band antenna based on

  7. Ultra-wide-band tellurite-based fiber Raman amplifier

    Microsoft Academic Search

    A. Mori; H. Masuda; K. Shikano; M. Shimizu

    2003-01-01

    We describe the first wide-band tellurite-based fiber Raman amplifier (T-FRA) for application to seamless ultra-large-capacity dense wavelength-division multiplexing (WDM) systems. First, we confirmed that the Raman scattering characteristics of the tellurite-based fiber has so large a gain coefficient and Stokes shift that we can achieve a wide-band tellurite-based fiber Raman amplifier with a shorter fiber length than when using silica-based

  8. Wideband optical storage

    NASA Technical Reports Server (NTRS)

    Heard, H. G.

    1979-01-01

    This paper has five purposes. First, to focus upon the key relationships that bound the technology choices for large, archival, digital storage devices; second, to identify the motivations for selecting the optical technology for a petabit-exabit level storage system (10 to the 15th to 10 to the 18th bits); third, to present a generic example and a specific implementation of a terabit-level optical storage device; fourth, to characterize the global design space constraints that will allow one to build a technology-limited optical store; and fifth, to sketch the outline of the BYTERON concept, a wideband 10 to the 16th to 10 to the 17th bit optical store concept and contrast its performance to that of an optical store that is in operation today

  9. AWACS: ATM Wireless Access System - potential candidate for European HIPERLINK standard

    Microsoft Academic Search

    C. Evci; A. De Hoz; R. Rheinschmitt; M. Araki; Mark A. Beach; Andrew R. Nix; P. Hafezi; Y. Sun; Sergio Barberis; E. Gaiani; B. Melis; G. Romano; Valerio Palestini; M. Tolonen; H. Hakalahti

    1999-01-01

    Wireless ATM is receiving a significant attention as a solution for wireless access. The integration of wireless access and ATM is an essential requirement for the future of telecommunications so that emerging wideband services which embody multimedia applications can be made transparently available to mobile terminals. There are many ongoing activities within the European ACTS program (Advanced Communications Technologies and

  10. Multi-Carrier Wideband Acoustic Communications Orthogonal frequency division multiplexing (OFDM) offers a viable approach to high-

    E-print Network

    Stojanovic, Milica

    broadcast (DAB, DVB) , and wireless local area networks (IEEE 802.11 LAN). It is also considered for frequency synchronization in OFDM radio systems have been extensively studied, and numerous algorithms haveMulti-Carrier Wideband Acoustic Communications Orthogonal frequency division multiplexing (OFDM

  11. A Wideband Spiral Antenna for Ingestible Capsule Endoscope Systems: Experimental Results in a Human Phantom and a Pig

    Microsoft Academic Search

    Sang Heun Lee; Jaebok Lee; Young Joong Yoon; Changyul Cheon; Kihyun Kim; Sangwook Nam

    2011-01-01

    This paper presents the design of a wideband spiral antenna for ingestible capsule endoscope systems and a compari- son between the experimental results in a human phantom and a pig under general anesthesia. As wireless capsule endoscope sys- tems transmit real-time internal biological image data at a high resolution to external receivers and because they operate in the human body,

  12. Wide-band CEBG-based Directive Antenna Halim Boutayeb*1, Tayeb A. Denidni1, Peter Perodeau2, and

    E-print Network

    Boyer, Edmond

    Wide-band CEBG-based Directive Antenna Halim Boutayeb*1, Tayeb A. Denidni1, Peter Perodeau2, and Alexandre Marsolais2 1 INRS-EMT, University of Quebec, Montreal, Canada. boutayeb@emt.inrs.ca 2 Ultra-Electronics- tennas or new beam switching antennas [1-3]. These structures are radially and circularly periodic

  13. MPAP: virtualization architecture for heterogenous wireless APs

    Microsoft Academic Search

    Yong He; Ji Fang; Jiansong Zhang; Haichen Shen; Kun Tan; Yongguang Zhang

    2011-01-01

    This demonstration shows a novel virtualization architecture, called Multi-Protocol Access Point (MPAP), which exploits the software radio technology to virtualize multiple heterogenous wireless standards on single radio hardware. The basic idea is to deploy a wide-band radio front-end to receive radio signals from all wireless standards sharing the same spectrum band, and use separate software base-bands to demodulate information stream

  14. IEEE ANTENNAS AND WIRELESS PROPAGATION LETTERS, VOL. 6, 2007 647 A T-Shaped Wide-Slot Harmonic

    E-print Network

    Park, Seong-Ook

    are only applied for narrow band antenna. For wideband application, a T-shaped wideband slot antennaIEEE ANTENNAS AND WIRELESS PROPAGATION LETTERS, VOL. 6, 2007 647 A T-Shaped Wide-Slot Harmonic, IEEE Abstract--This paper proposes a T-shaped wide-slot harmonic suppression antenna at 4 GHz. Harmonic

  15. Investigations on co-planar waveguide fed pentagon shape planar monopole ultra-wide bandwidth (UWB) antenna on foam substrate providing invariant radiation patterns

    Microsoft Academic Search

    Robert A. Moody; Satish K. Sharma

    2010-01-01

    It is well-established that the planar monopole antenna exhibits wideband impedance matching characteristics, high radiation efficiency, and an omni-directional pattern that makes it a desirable candidate for ultra-wideband (UWB) applications [1-2]. However, the radiation pattern deteriorates rapidly towards the high frequency end. Antennas fed with co-planar waveguides (CPW) have the further advantages of low dispersion for wideband applications, reduced radiation

  16. Time reversal of wideband microwaves

    Microsoft Academic Search

    G. Lerosey; J. de Rosny; A. Tourin; A. Derode; M. Fink

    2006-01-01

    In this letter, time reversal is applied to wideband electromagnetic waves in a reverberant room. To that end a multiantenna time reversal mirror (TRM) has been built. A 150 MHz bandwidth pulse at a central frequency of 2.45 GHz is radiated by a monopolar antenna, spread in time due to reverberation, recorded at the TRM, time reversed, and retransmitted. The

  17. 1370 IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 57, NO. 5, MAY 2009 Paper-Based RFID-Enabled Wireless

    E-print Network

    Tentzeris, Manos

    - tion (RFID), sensor, temperature, transmitter, ultra high frequency (UHF), wireless. I. INTRODUCTION- and monopole-based wireless sensor modules. high biodegradability with respect to other ceramic substrates

  18. Spatial Correlation and Eigenvalue Statistics Investigation of Wideband MIMO Channel Measurements

    Microsoft Academic Search

    Attaphongse Taparugssanagorn; Tommi Jämsä; Juha Ylitalo

    2006-01-01

    Spatial correlation is one of substantial factors for multiple-input multiple-output (MIMO) wireless communication systems. The spatial correlation must be therefore taken into account in system simulations. This paper results from outdoor wideband MIMO channel measurements performed at 2.53 GHz with a bandwidth of 100 MHz in urban microcell scenario. The measurements were conducted for vehicular speed of 20 km\\/h. A

  19. Evaluation of a New Wideband Slot Array for MIMO Performance Enhancement in Indoor WLANs

    Microsoft Academic Search

    Jorge R. Costa; Carla R. Medeiros; Carlos A. Fernandes

    2011-01-01

    A new wideband compact slot antenna array for indoor WLAN access points (AP) is described, covering several wireless communication services from 2.4 to 4.8 GHz, that is especially designed to enhance MIMO system capacity. The array topology provides both spatial and polarization diversity. Despite very close packing of the array elements, these exhibit very low mutual coupling and low cross-polarization,

  20. 3668 IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS, VOL. 7, NO. 10, OCTOBER 2008 Orthogonally-Spread Block Transmissions for

    E-print Network

    Giannakis, Georgios

    for higher data rates, simple baseband operation and ability to directly benefit from the UWB channel's rich-Spread Block Transmissions for Ultra-Wideband Impulse Radios Shahrokh Farahmand, Xiliang Luo, and Georgios B-wideband impulse radios (UWB- IR) can collect the rich multipath energy offered by UWB channels with a low

  1. Characterization of the bistable wideband optical filter on the basis of nonlinear 2D photonic crystal

    SciTech Connect

    Guryev, I. V., E-mail: guryev@ieee.org; Sukhoivanov, I. A., E-mail: guryev@ieee.org; Andrade Lucio, J. A., E-mail: guryev@ieee.org; Manzano, O. Ibarra, E-mail: guryev@ieee.org; Rodriguez, E. Vargaz, E-mail: guryev@ieee.org; Gonzales, D. Claudio, E-mail: guryev@ieee.org; Chavez, R. I. Mata, E-mail: guryev@ieee.org; Gurieva, N. S., E-mail: guryev@ieee.org [University of Guanajuato, Engineering division (Mexico)

    2014-05-15

    In our work, we investigated the wideband optical filter on the basis of nonlinear photonic crystal. The all-optical flip-flop using ultra-short pulses with duration lower than 200 fs is obtained in such filters. Here we pay special attention to the stability problem of the nonlinear element. To investigate this problem, the temporal response demonstrating the flip-flop have been computed within the certain range of the wavelengths as well as at different input power.

  2. Inter/Intra-Vehicle Wireless Communication file:///X:/www-docs/cse574-06/ftp/vehicular_wireless/index.html 1 of 16 5/9/2006 7:32 PM

    E-print Network

    Jain, Raj

    , Bluetooth, dedicated short range communication, ultra-wideband, ray optics, signal to noise ratio, omni of the emergency braking of a preceding vehicle, or the presence of an obstacle in the roadway. Such a network

  3. Communication for wideband fading channels : on theory and practice

    E-print Network

    Luo, Cheng, Ph. D. Massachusetts Institute of Technology

    2006-01-01

    This dissertation investigates some information theoretic aspects of communication over wideband fading channels and their applicability to design of signaling schemes approaching the wideband capacity limit. This work ...

  4. A novel antenna for ultra-wide-band applications

    Microsoft Academic Search

    Albert K. Y. Lai; Albert L. Sinopoli; Walter D. Burnside

    1992-01-01

    An ultra-wideband antenna based on a slotline feed structure, a bowtie horn, and a rolled edge termination was developed, analyzed, and measured. Empirical data showed that its beamwidths and bandwidth are dependent on its physical dimensions which are easily controllable by an antenna designer. Measured patterns of models with various radiation properties are shown to substantiate these design rules. A

  5. Evaluation of an ultra-wide-band propagation channel

    Microsoft Academic Search

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

    2002-01-01

    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

  6. A wideband magnetic energy harvester

    NASA Astrophysics Data System (ADS)

    Zhang, C. L.; Chen, W. Q.

    2010-03-01

    A wideband magnetic energy harvester is proposed by using a number of multiferroic composite fibers of different lengths which are connected in parallel or series. The structural theory is employed to characterize the magnetoelectroelastic behavior of the fibers. A global circuit analysis is then performed. It is shown that such a structure of energy harvester is capable of collecting the ambient magnetic energy over a wide frequency range.

  7. ESD protection for wideband RF CMOS LNAs

    Microsoft Academic Search

    D. Linten; S. Thijs; G. Groeseneken

    2010-01-01

    Providing ESD protection for wideband RF CMOS LNAs is a challenging task: it requires both ESD and RF design skills in order to achieve high ESD robustness, while maintaining the overall RF performance. In this paper, an overview of the different wideband RF ESD protection strategies used in the literature is presented.

  8. ADVANCED DISTRIBUTED WIDEBAND DATA ACQUISITION SYSTEM

    Microsoft Academic Search

    Albert Berdugo

    Wideband data acquisition units have been used as part of an instrumentation system for several decades. Historically, these units operated asynchronously from each other, and from the rest of the instrumentation system when installed on the same test vehicle. When many wideband units are required to slave their formats or sampling rate to the test vehicle's event of interest such

  9. A new method for adaptive wideband beamforming

    Microsoft Academic Search

    R. DeLap; A. Hero

    1993-01-01

    Classical angle of arrival (AOA) estimation methods assume incoming signals are either purely narrowband or purely wideband in nature. There are many physical scenarios where this may not be the case. The authors call such scenarios mixed, in that the incoming signals contain a combination of both wideband and narrowband components. They introduce a new method for performing AOA estimation

  10. Wide-band piezoelectric polymer acoustic sources

    Microsoft Academic Search

    PETER A. LEWIN; M. E. Schafer

    1988-01-01

    The design of a wideband acoustic source made of the piezoelectric polymer polyvinylidine fluoride (PVDF) is described. The source was developed for the characterization and absolute calibration of ultrasonic hydrophone probes. Construction details are described and performance characteristics of the wideband PVDF transmitter, including its transmitting voltage response and directivity patterns, are compared with theoretical predictions in the frequency range

  11. Robust wavefield interpolation for adaptive wideband beamforming

    Microsoft Academic Search

    Miriam A. Doron; Amir Nevet

    2008-01-01

    In this paper we consider the application of interpolation-based focusing for wideband array processing and direction finding using wavefield interpolation matrices. The focusing approach exploits the wideband characteristic of the signals for coherent subspace processing, achieving improved performance and reduced computational complexity. We investigate the use of wavefield modeling-based frequency transformations of the array manifold, which are data independent and

  12. An Undergraduate Research Experience: Wireless Propagation and Position Location in a Forest Environment

    NSDL National Science Digital Library

    Anderson, Christopher

    Over the past several years, the undergraduate curriculum at many universities has been evolving to incorporate laboratory exercises and research projects to reinforce and support traditional classroom lectures. In particular, involving undergraduates in meaningful research projects is a key to providing them with the hands-on activities students are demanding. Unfortunately, two areas in the electrical engineering curriculum are suffering from a lack of meaningful hands-on learning activities: electromagnetics and communications. At many universities, electromagnetics is taught as a highly theoretical, highly mathematical class with the goal of providing students a deep understanding of Maxwells equations. Students that complete such a course generally struggle when faced with applying Maxwells equations to real-world electromagnetics problems such as transmission lines, antenna design, or wireless propagation. Introductory communications courses may have laboratory components, however, involving students in an undergraduate research project is an excellent mechanism to supplement and reinforce the laboratory exercises. This paper presents a summer undergraduate research experience that involved characterizing ultra wideband wireless propagation and position location in a forest environment. Four undergraduate students were selected to participate in the research experience. All four students had taken the basic electromagnetics and communications courses, although only one had prior hands-on experience. Additionally, the use of impulse ultra-wideband signals represented a new wireless communication scheme that students had to master at the beginning of the research experience. After an initial training period, students were tasked with site selection, experimental design, recording measurements, analyzing data, and troubleshooting equipment failures. Although it is too early to assess the impact of the research experience on these students careers, the experience appears to have been a success. All four students reported a greater depth of understanding of the concepts taught in electromagnetics and communications courses. Additionally, students gained valuable experience in developing and carrying out field experiments sometimes in less than ideal conditions and as a result of this experience, some students expressed a desire to pursue a graduate degree. Designing this research project also provided several valuable lessons to the instructors which will aid in the further development of hands-on learning activities for electromagnetics and communications courses.

  13. Analysis and design of a wideband dual-polarized antenna based on the principle of Huygens' source

    NASA Astrophysics Data System (ADS)

    Seo, Hyukjun

    Analysis and designs of wideband dual-polarized antennas for mobile wireless communication systems are presented. The concept for Huygens' sources, which are combinations of electric and magnetic dipoles, is used. As a result a wideband unidirectional antenna, which consists of a planar dipole and a slot, is selected for the antenna element. This study aims at designing a dually polarized antenna with wideband performance. The first part of the study discusses the performance of the linearly polarized antenna element at 2.5 GHz. Several design parameters associated with the antenna element are addressed. To improve the performance and increase the bandwidth, a twin-fed hook-shaped probe feeding technique is applied. Prototype antennas are fabricated and tested, and good agreement between the simulated and measured results is obtained. The second part of this study is extended to design the wideband dual-polarized patch antenna. Problems associated with the practical implementation of the dual-polarized antenna in printed form are discussed. The wideband performance of the present antenna is examined by shielding the dielectric substrate from the radiating region. The proposed antenna is fabricated and tested. In addition, a metallic side wall is adopted for suppressing the back radiation. The study for designing a possible candidate for a novel dual-polarized antenna by embedding an electromagnetic bandgap (EBG) structure is investigated. Analysis for unit-cells of mushroom-like and wideband uniplanar EBG structures is performed, and simple monopoles are used for exciting the EBG embedded antenna. The presented antennas find many possible applications in many recent wireless communication systems like 3G, 3GPP Long Term Evolution (LTE), 4G, Wi-MAX, and Wi-Bro.

  14. Constrained state estimation for individual localization in wireless body sensor networks.

    PubMed

    Feng, Xiaoxue; Snoussi, Hichem; Liang, Yan; Jiao, Lianmeng

    2014-01-01

    Wireless body sensor networks based on ultra-wideband radio have recently received much research attention due to its wide applications in health-care, security, sports and entertainment. Accurate localization is a fundamental problem to realize the development of effective location-aware applications above. In this paper the problem of constrained state estimation for individual localization in wireless body sensor networks is addressed. Priori knowledge about geometry among the on-body nodes as additional constraint is incorporated into the traditional filtering system. The analytical expression of state estimation with linear constraint to exploit the additional information is derived. Furthermore, for nonlinear constraint, first-order and second-order linearizations via Taylor series expansion are proposed to transform the nonlinear constraint to the linear case. Examples between the first-order and second-order nonlinear constrained filters based on interacting multiple model extended kalman filter (IMM-EKF) show that the second-order solution for higher order nonlinearity as present in this paper outperforms the first-order solution, and constrained IMM-EKF obtains superior estimation than IMM-EKF without constraint. Another brownian motion individual localization example also illustrates the effectiveness of constrained nonlinear iterative least square (NILS), which gets better filtering performance than NILS without constraint. PMID:25390408

  15. A framework for UWB-based communication and location tracking systems for wireless sensor networks.

    PubMed

    Chóliz, Juan; Hernández, Angela; Valdovinos, Antonio

    2011-01-01

    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

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

    PubMed Central

    Chóliz, Juan; Hernández, Ángela; Valdovinos, Antonio

    2011-01-01

    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

  17. Constrained State Estimation for Individual Localization in Wireless Body Sensor Networks

    PubMed Central

    Feng, Xiaoxue; Snoussi, Hichem; Liang, Yan; Jiao, Lianmeng

    2014-01-01

    Wireless body sensor networks based on ultra-wideband radio have recently received much research attention due to its wide applications in health-care, security, sports and entertainment. Accurate localization is a fundamental problem to realize the development of effective location-aware applications above. In this paper the problem of constrained state estimation for individual localization in wireless body sensor networks is addressed. Priori knowledge about geometry among the on-body nodes as additional constraint is incorporated into the traditional filtering system. The analytical expression of state estimation with linear constraint to exploit the additional information is derived. Furthermore, for nonlinear constraint, first-order and second-order linearizations via Taylor series expansion are proposed to transform the nonlinear constraint to the linear case. Examples between the first-order and second-order nonlinear constrained filters based on interacting multiple model extended kalman filter (IMM-EKF) show that the second-order solution for higher order nonlinearity as present in this paper outperforms the first-order solution, and constrained IMM-EKF obtains superior estimation than IMM-EKF without constraint. Another brownian motion individual localization example also illustrates the effectiveness of constrained nonlinear iterative least square (NILS), which gets better filtering performance than NILS without constraint. PMID:25390408

  18. Realistic modeling of the biological channel for the design of implantable wireless UWB communication systems.

    PubMed

    Bahrami, Hadi; Gosselin, Benoit; Rusch, Leslie A

    2012-01-01

    Several emerging medical applications require that a miniature data acquisition device be implanted into the head to extract and wirelessly communicate brain activity to other devices. Designing a reliable communication link for such an application requires a realistic model of the surrounding biological tissues. This paper exploits a realistic model of the biological channel to design a suitable wireless ultra wideband communication link in a brain monitoring application. Two scenarios for positioning the implanted transmitting antenna are considered. The 1(st) scenario places the antenna under the skull, whereas the 2(nd) scenario places the antenna under the skin, above the skull. The propagation characteristics of the signal through the tissues of the human head have been determined with full-wave electromagnetic simulation based on Finite Element Method. The implantable antenna and the external antenna are key components to establish an electromagnetic link between an implanted transmitter and an external receiver. The average specific absorption rate (ASAR) of the implantable antennas are evaluated and compared for the two proposed scenarios. Moreover, the maximum available power from the implanted antenna is evaluated to characterize the performance of the communication link established between the implantable antenna and the external antenna, with respect to spectrum and safety regulations. We show how sensitive the receiver must be in order to implement a reliable telemetry link based on the proposed model of the channel. PMID:23367300

  19. Wireless network system based multi-non-invasive sensors for smart home

    NASA Astrophysics Data System (ADS)

    Issa Ahmed, Rudhwan

    There are several techniques that have been implemented for smart homes usage; however, most of these techniques are limited to a few sensors. Many of these methods neither meet the needs of the user nor are cost-effective. This thesis discusses the design, development, and implementation of a wireless network system, based on multi-non-invasive sensors for smart home environments. This system has the potential to be used as a means to accurately, and remotely, determine the activities of daily living by continuously monitoring relatively simple parameters that measure the interaction between users and their surrounding environment. We designed and developed a prototype system to meet the specific needs of the elderly population. Unlike audio-video based health monitoring systems (which have associated problems such as the encroachment of privacy), the developed system's distinct features ensure privacy and are almost invisible to the occupants, thus increasing the acceptance levels of this system in household environments. The developed system not only achieved high levels of accuracy, but it is also portable, easy to use, cost-effective, and requires low data rates and less power compared to other wireless devices such as Wi-Fi, Bluetooth, wireless USB, Ultra wideband (UWB), or Infrared (IR) wireless. Field testing of the prototype system was conducted at different locations inside and outside of the Minto Building (Centre for Advanced Studies in Engineering at Carleton University) as well as other locations, such as the washroom, kitchen, and living room of a prototype apartment. The main goal of the testing was to determine the range of the prototype system and the functionality of each sensor in different environments. After it was verified that the system operated well in all of the tested environments, data were then collected at the different locations for analysis and interpretation in order to identify the activities of daily living of an occupant.

  20. A wideband EMP test system

    SciTech Connect

    Rohwein, G.J.; Aurand, J.F.; Frost, C.A.; Roose, L.D.; Babcock, S.R.

    1994-07-01

    A wideband EMP tester consisting of a high voltage modulator, transmission line, high voltage peaking switch, and a TEM test cell has been developed that delivers repetitive high frequency EMP pulses to an RF-sealed double-test volume of about 1 ft.{sup 3}. The pulse shape is rectangular, has a duration of 4 ns and a risetime of 120 ps. The system can be operated at pulse repetition rates up to 1500 Hz and electric field levels up to 125 kV/m. Both voltage and pulse rate are continuously adjustable over these ranges may be operated in any combination.

  1. Time reversal of wideband microwaves

    NASA Astrophysics Data System (ADS)

    Lerosey, G.; de Rosny, J.; Tourin, A.; Derode, A.; Fink, M.

    2006-04-01

    In this letter, time reversal is applied to wideband electromagnetic waves in a reverberant room. To that end a multiantenna time reversal mirror (TRM) has been built. A 150MHz bandwidth pulse at a central frequency of 2.45GHz is radiated by a monopolar antenna, spread in time due to reverberation, recorded at the TRM, time reversed, and retransmitted. The time-reversed wave converges back to its source and focus in both time and space. The time compression is studied versus the number of antennas in the TRM and its bandwidth. The focal spot is also measured thanks to an eight-channel receiving array.

  2. Fundamental limits of wideband localization

    E-print Network

    Shen, Yuan, Ph. D. Massachusetts Institute of Technology

    2008-01-01

    Location-awareness is essential for many wireless network applications. However, determining nodes' positions precisely is a challenging task, especially in harsh multipath propagation environments. To address this problem, ...

  3. Call Admission Control in OFDM Wireless Multimedia Networks

    Microsoft Academic Search

    Yan Zhang

    2008-01-01

    Call admission control is an effective mechanism to guarantee robust services in wireless networks. In this paper, we present several call admission control algorithms and queueing models for the subcarrier allocation in the OFDM-based wireless multimedia networks. Call connection requests are differentiated into narrow-band call and wide-band call. For either class of calls, the traffic process is characterized as batch

  4. Simulation Study of Ultra-Wideband Communication System Tefera Tibebe

    E-print Network

    Haddadi, Hamed

    & Electrical Engineering University College London Abstract: This paper provides a brief overview of one by pulsed emissions, where a very wide RF bandwidth is related to a narrow pulse width. Unlike many conventional radio transmitters in which a modulated signal is upconverted & amplified, in UWB systems

  5. Ultra-Wideband Microstrip Antenna with Coupled Notch Circuit

    E-print Network

    Bornemann, Jens

    . The antenna is often tasked with providing both the wide frequency range and narrowband notch which should within antenna structures, ground plane or feed lines to suppress unwanted narrow-band signals, e.g. [1 on employing two single Electromagnetic Band Gap (EBG) structures coupled to the feed line of the antenna

  6. SHORT-RANGE ULTRA-WIDEBAND SYSTEMS Principal Investigator

    E-print Network

    Southern California, University of

    mobile and dense multipath links), antenna design for UWB links, coexistence with interference, energy. We will use short-range UWB radio applications in these environments as one key means of focusing our applications" for UWB technology. This work is supported by good lab facilities at all three participating

  7. Dual-shorted monopole antenna for Ultra-Wideband application

    Microsoft Academic Search

    Chun-I Lin; Tzung-Wern Chiou; Sheng-Chih Lin; Fu-Ren Hsiao

    2008-01-01

    A novel dual-shorted monopole antenna suitable for UWB application, especially as an internal antenna for notebook or tablet PC has been proposed. The proposed antenna has a simple structure with a dual-shorted strip and is easy to implement at a low cost. Prototypes of the proposed antenna have been constructed and studied. A very uniform surface current distribution in the

  8. Compact Coupled Sectorial loops Antennas for Ultra-Wideband Applications

    Microsoft Academic Search

    Adel Elsherbini; Kamal Sarabandi

    This paper presents the structure and design of a number of significant modifications to the UWB coupled sectorial loops antennas (CSLA) to achieve further size reduction and unidirectional radiation over a very wide band. The variations of the radiation pattern at high frequencies of the original CSLA were less than desirable. Also, for many applications, unidirectional radiation pattern over a

  9. Investigations into printed monopole antennas for ultra-wideband applications

    Microsoft Academic Search

    S. K. Padhi; S. Zagriatski; S. Crozier; M. E. Bialkowski

    2005-01-01

    The paper reports an investigation into various designs of printed planar monopole antennas for UWB applications. Three different designs (designated Ant I, Ant II and Ant III) have been chosen and investigated. Ant I uses a straight feed line, while Ant II and Ant III use a tapered feed line. The taper length and angle have been optimized with HFSS.

  10. A Fully Integrated CMOS Transmitter for Ultra-wideband Applications

    Microsoft Academic Search

    Tao Yuan; Yuanjin Zheng; Chyuen-Wei Ang; Le-Wei Li

    2007-01-01

    In this paper, a fully integrated CMOS UWB transmitter is presented. The transmitter consists of a band-notched UWB antenna and a transmitter IC which integrates a pulse generator, a gating signal generator and driver amplifiers. The drive amplifier employs a 2-stage amplifier-a class-E amplifier and a class-A amplifier with switch control, to significantly reduce power consumption. Fabricated using a 0.18-mum

  11. Impulse transmitting photonic antenna for ultra-wideband applications

    Microsoft Academic Search

    A. Chizh; S. Malyshev; S. Jefremov; B. Levitas; I. Naidionova

    2010-01-01

    This paper presents a new transmitting photonic antenna based on pigtailed fiber-optic photodiode module integrated with bow-tie radiator for UWB pulse generation using a gain-switched laser diode module.

  12. Transmission and Reception by Ultra-Wideband (UWB) Antennas

    Microsoft Academic Search

    Debalina Ghosh; Arijit de; Mary Taylor; Tapan Sarkar; Michael Wicks; Eric Mokole

    2006-01-01

    Broadband antennas are very useful in many applications because they operate over a wide range of frequencies. The objective of this paper is to study the transient responses of various well-known antennas over broad frequency ranges. As such, the phase responses of these antennas as a function of frequency are of great interest. In the ensuing analysis, each antenna is

  13. ULTRA WIDEBAND SYSTEMS, TECHNOLOGIES AND APPLICATIONS SPECIAL SECTION

    E-print Network

    Hao, Yang

    behaviour are also demonstrated. Results and analyses highlight the consequences of changes in body postures extension of the human mind. Body-centric networks consist of a number of nodes and units placed on the human body or in close proximity such as on everyday clothing [1]. Since low-power transmission

  14. Ultra wideband antenna array processing under spatial aliasing 

    E-print Network

    Shapoury, Alireza

    2009-05-15

    . : : : : : : : : : : : : : : 82 III Results with time dependent observations. : : : : : : : : : : : : : : : 84 x LIST OF FIGURES FIGURE Page 1 Disposition of a uniform linear array. : : : : : : : : : : : : : : : : : : 5 2 A typical broadband octave nested array.... : : : : : : : : : : : : : : : : : : : : : : : : : : 20 4 The onset of the grating lobes. : : : : : : : : : : : : : : : : : : : : : 22 5 The nonlinear relationship between the number of the aliasing angles, the true angle and the aperture size. : : : : : : : : : : : : : : 23 6 MLE-based estimate...

  15. Ultra wideband antenna array processing under spatial aliasing

    E-print Network

    Shapoury, Alireza

    2009-05-15

    - ments indicate that this assumption may not hold true globally over time as the interferences exhibit a time-dependant pattern and require a more elaborate model, based on time series analysis (See Appendix A). The journal model is IEEE Transactions... quickly for ! > B. This interpretation is frequently referred to the signal narrow-band assumption. Note that in the case of Uniform Linear Arrays, ?m=(m?1)dsin(?)=c. If the frequency of the standard ULA array (in which d=? = 1=2) is !std, then !?M = (M ?1...

  16. Ultra-wideband radar: Research and development considerations

    NASA Astrophysics Data System (ADS)

    1989-06-01

    An initial investigation into the technology of impulse radar is provided. The principal purpose is to provide a road map for exploratory development by defining critical technology issues for a research investment strategy. There are urgent requirements for improving radar capability for target identification or noncooperative target recognition (NCTR). Progress in NCTR was primarily in information processing, with few technological advances in the sensor domain. Impulse radar provides new and revolutionary ideas which can offer new capabilities for active surveillance. These capabilities are discussed along with issues that must be resolved before system development is undertaken.

  17. Perfect Space-Time Block Codes and Ultra-Wideband

    Microsoft Academic Search

    Kei Hao

    cannot be used in UWB systems, however it was shown that ST codes designed for flat fading channels still provide at least the some advantage even in the presence of frequency-selective fading channels (4). With the objective to give an answer or opinion whether the perfect codes can be used in UWB systems, we proceed as follow. We investigate the

  18. Evolutionary games in wireless networks.

    PubMed

    Tembine, Hamidou; Altman, Eitan; El-Azouzi, Rachid; Hayel, Yezekael

    2010-06-01

    We consider a noncooperative interaction among a large population of mobiles that interfere with each other through many local interactions. The first objective of this paper is to extend the evolutionary game framework to allow an arbitrary number of mobiles that are involved in a local interaction. We allow for interactions between mobiles that are not necessarily reciprocal. We study 1) multiple-access control in a slotted Aloha-based wireless network and 2) power control in wideband code-division multiple-access wireless networks. We define and characterize the equilibrium (called evolutionarily stable strategy) for these games and study the influence of wireless channels and pricing on the evolution of dynamics and the equilibrium. PMID:19963703

  19. Spectrum sharing for next generation wireless communication networks

    Microsoft Academic Search

    Sanjay Kumar; Gustavo Costa; Shashi Kant; Flemming Bjerge Frederiksen; Nicola Marchetti; Preben Mogensen

    2008-01-01

    Future wireless services are expected to provide data-rates in the order of 1 Gbps in local area and 100 Mbps in wide area. A very wide bandwidth is required to support such high rates, in the order of 100 MHz: this wideband will not be available for each operator, thus a shared access to the spectrum among operators is needed.

  20. Multipath Channel Models for Wireless Local and Metropolitan Area Networks

    Microsoft Academic Search

    Kyungsoo Jeong; S. H. Kim; K. M. Chung; J. C. Kim; J. H. Yu; J. S. Lee; S. H. Seo

    2005-01-01

    Wideband mobile radio channel characteristics were measured in various environments in Korea. SKT conducted impulse response measurements at 2.3 GHz with a commercial channel sounder and presents multipath channel models for wireless local and metropolitan area networks. In this paper, we describe the process to analyze the measured data and build tapped delay line channel models. The whole measurements were

  1. Indoor channel characterisation measurements with directional antennas for future high frequency ATM wireless access systems

    Microsoft Academic Search

    Y. Sun; P. Hafezi; A. Nix; M. Beach

    1997-01-01

    This paper presents a selection of wideband channel sounding measurements performed as part of the ACTS AWACS (ATM Wireless Access Communications System) project. The results were obtained for two different indoor operating environments (mainly in line-of-sight conditions) at a carrier frequency of 19.37 GHz. The paper discusses the configuration of the wideband channel sounder and its connection to the prototype

  2. A traffic behavior-aware fair call admission control for heterogeneous services in wireless networks

    Microsoft Academic Search

    Ki-II Kim; Sung-Kee Noh; Young-Ha Hwang; Sang-Ha Kim

    2004-01-01

    Fair call admission control (CAC) for heterogeneous services with different traffic properties, such as wideband and narrowband calls, is an important subject in wireless networks. B.M. Epstein et al. (see IEEE JSAC, vol.18, no.3, p.523-34, 2000) proposed a novel CAC scheme, independent multiclass one-step prediction with complete sharing and reservation (IMOSP-CS and IMOSP-RES), which ensures that wideband calls are not

  3. A novel wideband gyrotron travelling wave amplifier

    E-print Network

    Sirigiri, Jagadishwar R. (Jagadishwar Rao), 1973-

    2003-01-01

    We present the design and the experimental results of a novel wideband quasioptical Gyrotron Traveling Wave Tube (gyro-TWT) amplifier and the first Vacuum Electron Device (VED) with a Photonic Band Gap (PBG) structure. The ...

  4. LSP quantization in wideband speech coders

    Microsoft Academic Search

    M. Ferhaoui; S. Van Gerven

    1999-01-01

    This paper deals with multi-stage vector quantization of line spectrum pair (LSP) parameters in wideband speech coders and discusses commonly used spectral distortion measures and their relation to the perceptual quality of the speech coding

  5. Wideband CDMA system for personal radio communications

    Microsoft Academic Search

    A. Fukasawa; T. Sato; Y. Takizawa; T. Kato; N. Kawabe; R. E. Fisher

    1996-01-01

    This article describes a wideband spread code-division multiple access (W-CDMA) system for high-capacity and high-quality personal radio communication. This system has been authorized as an EIA\\/TIA Interim Standard IS-665, T1P1 Trial Use Standard J-STD-015, and ITU-R Recommendation M 1073. The system uses wideband spreading to accomplish good interference immunity, high-quality speech, and high-speed data transmission. The system uses coherent detection

  6. Wideband Envelope Elimination and Restoration Power Amplifier with High Efficiency Wideband Envelope Amplifier for WLAN

    E-print Network

    Asbeck, Peter M.

    is the product of the envelope amplifier efficiency and RF transistor drain efficiency, i.e: transistorWideband Envelope Elimination and Restoration Power Amplifier with High Efficiency Wideband Envelope Amplifier for WLAN 802.11g Applications Feipeng Wang, Donald Kimball, Jeremy Popp*, Annie Yang

  7. SECURING WIRELESS SECURING WIRELESS

    E-print Network

    such as an office building or building complex. Since they transmit data through radio frequencies, wireless function within the range of the wireless network, usually limited to an area such as an office building or building complex. Since they transmit data through radio frequencies, wireless networks are open

  8. Wideband Timing of Millisecond Pulsars

    NASA Astrophysics Data System (ADS)

    Pennucci, Timothy; Demorest, Paul; Ransom, Scott M.; North American Nanohertz ObservatoryGravitational Waves (Nanograv)

    2015-01-01

    The use of backend instrumentation capable of real-time coherent dedispersion of relatively large fractional bandwidths has become commonplace in pulsar astronomy. However, along with the desired increase in sensitivity to pulsars' broadband signals, a larger instantaneous bandwidth brings a number of potentially aggravating effects that can lead to degraded timing precision. In the case of high-precision timing experiments, such as the one being carried out by the North American Nanohertz Observatory for Gravitational Waves (NANOGrav), subtle effects such as unmodeled intrinsic profile evolution with frequency, interstellar scattering, and dispersion measure variation are potentially capable of reducing the experiment's sensitivity to a gravitational wave signal. In order to account for some of these complications associated with wideband observations, we augmented the traditional algorithm by which the fundamental timing quantities are measured. Our new measurement algorithm accommodates an arbitrary two-dimensional model ``portrait'' of a pulsar's total intensity as a function of observing frequency and rotational phase, and simultaneously determines the time-of-arrival (TOA), the dispersion measure (DM), and per-frequency-channel amplitudes that account for interstellar scintillation. Our publicly available python code incorporates a Gaussian-component modeling routine that allows for independent component evolution with frequency, a ``fiducial component'', and the inclusion of scattering. Here, we will present results from the application of our wideband measurement scheme to the suite of NANOGrav millisecond pulsars, which aimed to determine the level at which the experiment is being harmed by unmodeled profile evolution. We have found thus far, and expect to continue to find, that our new measurements are at least as good as those from traditional techniques. At a minimum, by largely reducing the volume of TOAs we will decrease the computational demand associated with probing posterior distributions in the search for gravitational waves. The development of this algorithm is well-motivated by the promise of even larger fractional bandwidth receiver systems in the future of pulsar astronomy.

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

    PubMed

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

    2009-08-01

    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

  10. Wireless rake-receiver using adaptive filter with a family of partial update algorithms in noise cancellation applications

    NASA Astrophysics Data System (ADS)

    Fayadh, Rashid A.; Malek, F.; Fadhil, Hilal A.; Aldhaibani, Jaafar A.; Salman, M. K.; Abdullah, Farah Salwani

    2015-05-01

    For high data rate propagation in wireless ultra-wideband (UWB) communication systems, the inter-symbol interference (ISI), multiple-access interference (MAI), and multiple-users interference (MUI) are influencing the performance of the wireless systems. In this paper, the rake-receiver was presented with the spread signal by direct sequence spread spectrum (DS-SS) technique. The adaptive rake-receiver structure was shown with adjusting the receiver tap weights using least mean squares (LMS), normalized least mean squares (NLMS), and affine projection algorithms (APA) to support the weak signals by noise cancellation and mitigate the interferences. To minimize the data convergence speed and to reduce the computational complexity by the previous algorithms, a well-known approach of partial-updates (PU) adaptive filters were employed with algorithms, such as sequential-partial, periodic-partial, M-max-partial, and selective-partial updates (SPU) in the proposed system. The simulation results of bit error rate (BER) versus signal-to-noise ratio (SNR) are illustrated to show the performance of partial-update algorithms that have nearly comparable performance with the full update adaptive filters. Furthermore, the SPU-partial has closed performance to the full-NLMS and full-APA while the M-max-partial has closed performance to the full-LMS updates algorithms.

  11. Centralized Collaborative Compressed Sensing of Wideband Spectrum for Cognitive Radios

    E-print Network

    Paris-Sud XI, Université de

    1 Centralized Collaborative Compressed Sensing of Wideband Spectrum for Cognitive Radios Hessam technique for cognitive radio systems which combines algebraic tools and compressive sampling techniques, spectrum sensing, cognitive radio, distri- bution discontinuities, algebraic detection, wideband. I

  12. Quasi-orthogonal wideband radar waveforms based on chaotic systems

    E-print Network

    Willsey, Matt (Matt S.)

    2007-01-01

    With the development of A/D converters possessing sufficiently high sampling rates, it is now feasible to use arbitrary, wideband waveforms in radar applications. Large sets of quasi-orthogonal, wideband waveforms can be ...

  13. Current wideband MILSATCOM infrastructure and the future of bandwidth availability

    Microsoft Academic Search

    Kendra L. B. Cook

    2009-01-01

    The military satellite communications (MILSATCOM) infrastructure is typically broken into three categories: wideband, protected, and narrowband. Wideband systems emphasize high capacity, protected systems prioritize anti-jam features and covertness, and narrowband systems emphasize support to the disadvantaged user by providing low data rate communications to small \\/ mobile users. This paper focuses on the existing wideband MILSATCOM infrastructure (namely the Defense

  14. Current wideband MILSATCOM infrastructure and the future of bandwidth availability

    Microsoft Academic Search

    Kendra L. B. Cook

    2010-01-01

    The military satellite communications (MILSATCOM) infrastructure is typically broken into three categories: wideband, protected, and narrowband. Wideband systems emphasize high capacity, protected systems prioritize anti-jam features and covertness, and narrowband systems emphasize support to the disadvantaged user by providing low data rate communications to small\\/mobile users. This focuses on the existing wideband MILSATCOM infrastructure (namely the Defense Satellite Communications System

  15. Time-Hopping Sequence Design for Narrowband Interference Suppression

    E-print Network

    Kavcic, Aleksandar

    for coexistence of Ultra-Wideband (UWB) systems with other wireless systems. Specifically, we consider the design) issued Ultra-Wideband (UWB) regulations, under Part 15 of the Commission's rules, permitting UWB], directional antennas, notch filters [7] and pulse shaping [8] for wideband systems currently exist

  16. A novel goblet shaped patch antenna for ultra wide band applications

    Microsoft Academic Search

    G. A. Lodi; R. I. Zafar; M. Bilal

    2010-01-01

    The paper presents a novel design for an ultra wideband antenna which operates from 2.8-11.8 GHz, covering the entire ultra wide band (UWB) frequency range of 3.1 to 10.6 GHz, as approved by FCC. The antenna is in the form of a goblet (chalice) with a partial ground plane. In the paper, antenna design and geometry is described in detail.

  17. Challenge: Ultra-Low-Power Energy-Harvesting Active Networked Tags (EnHANTs)

    E-print Network

    Zussman, Gil

    ]@ee.columbia.edu danr@cs.columbia.edu, [wangx, gil]@ee.columbia.edu ABSTRACT This paper presents the design challenges be attached to objects that are traditionally not networked (e.g., books, clothing, and produce), thereby, ultra-wideband (UWB) circuit design, and organic electronic harvesting techniques will enable

  18. Cross slot antenna with open ended truncated patch feed for ultra wide band applications

    Microsoft Academic Search

    D. Helena Margaret; S. Anith; M. Duraisamy; K. P. K. Muneeswaran

    2009-01-01

    A novel design of an ultra-wideband (UWB) slot antenna is presented. This antenna operates as a transmitter and receiver antenna. Effects of the antenna dimensional parameters are studied through experimental and simulation results. The design procedures are developed and verified for UWB frequency band. Antenna gain and directivity at bore sight and in their maximum states are close to each

  19. Multiband and miniaturized antenna design for ultra wide band applications with band rejection characteristic

    Microsoft Academic Search

    Mehmet Toycan; Ademola Kaka; Vali Bashiry; Serkan Abbasoglu

    2012-01-01

    In this paper, the combination of concentric square loop and the Koch curve fractal geometries based microstrip antenna design for ultra wideband (UWB) applications is presented. This fractal structure is implemented on a empty square. Three progressively concentric square loop is applied inside the empty square and a full square is applied to the center for the first iteration. Then,

  20. Measurement and modeling of an ultra-wide bandwidth indoor channel

    Microsoft Academic Search

    Saeed S. Ghassemzadeh; Rittwik Jana; Christopher W. Rice; William Turin; Vahid Tarokh

    2004-01-01

    This paper describes the results of frequency domain channel sounding in residential environments. It consists of detailed characterization of complex frequency responses of Ultra-Wideband Band (UWB) signals having a nominal center frequency of 5 GHz. A path loss model as well as a second-order Autoregressive (AR) model is proposed for frequency response generation of the UWB indoor channel. Probability distributions

  1. Wideband Agile Digital Microwave Radiometer

    NASA Technical Reports Server (NTRS)

    Gaier, Todd C.; Brown, Shannon T.; Ruf, Christopher; Gross, Steven

    2012-01-01

    The objectives of this work were to take the initial steps needed to develop a field programmable gate array (FPGA)- based wideband digital radiometer backend (>500 MHz bandwidth) that will enable passive microwave observations with minimal performance degradation in a radiofrequency-interference (RFI)-rich environment. As manmade RF emissions increase over time and fill more of the microwave spectrum, microwave radiometer science applications will be increasingly impacted in a negative way, and the current generation of spaceborne microwave radiometers that use broadband analog back ends will become severely compromised or unusable over an increasing fraction of time on orbit. There is a need to develop a digital radiometer back end that, for each observation period, uses digital signal processing (DSP) algorithms to identify the maximum amount of RFI-free spectrum across the radiometer band to preserve bandwidth to minimize radiometer noise (which is inversely related to the bandwidth). Ultimately, the objective is to incorporate all processing necessary in the back end to take contaminated input spectra and produce a single output value free of manmade signals to minimize data rates for spaceborne radiometer missions. But, to meet these objectives, several intermediate processing algorithms had to be developed, and their performance characterized relative to typical brightness temperature accuracy re quirements for current and future microwave radiometer missions, including those for measuring salinity, soil moisture, and snow pack.

  2. Printed Antenna Elements with Attested Ultra Wide Band Array Applicability

    Microsoft Academic Search

    F. M. Tanyer-Ti?rek

    2010-01-01

    Ultra-wideband (UWB) is a radio technology that can be used at very low energy levels, for short-range high-bandwidth communications, by using a large radio spectrum. Due to its high speed rate, this technology is nowadays one of the most promising solutions for communications. Maximum data that can be transmitted per second over a communication channel can be high since the

  3. Low Power Filtering Techniques for Wideband and Wireless Applications 

    E-print Network

    Gambhir, Manisha

    2010-10-12

    architecture. The prototype fabricated in standard 0.35um CMOS process shows -41dB of IM3 for 250mV peak to peak swing with 8.6mW/pole of power dissipation. Also, an LC prototype implemented using similar architecture is discussed in brief. It is shown that...

  4. Low Power Filtering Techniques for Wideband and Wireless Applications

    E-print Network

    Gambhir, Manisha

    2010-10-12

    architecture. The prototype fabricated in standard 0.35um CMOS process shows -41dB of IM3 for 250mV peak to peak swing with 8.6mW/pole of power dissipation. Also, an LC prototype implemented using similar architecture is discussed in brief. It is shown that...

  5. 30 pJ/b, 67 Mbps, Centimeter-to-Meter Range Data Telemetry With an IR-UWB Wireless Link.

    PubMed

    Ebrazeh, Ali; Mohseni, Pedram

    2014-08-12

    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

  6. Wideband Spectrum Sensing in Cognitive Radio Networks

    Microsoft Academic Search

    Zhi Quan; Shuguang Cui; Ali H. Sayed; H. Vincent Poor

    2008-01-01

    Spectrum sensing is an essential enabling function- ality for cognitive radio networks to detect spectrum holes and opportunistically use the under-utilized frequency bands without causing harmful interference to legacy networks. This paper introduces a novel wideband spectrum sensing technique, called multiband joint detection, which jointly detects the signal energy levels over multiple frequency bands rather than consider one band at

  7. Radio-Frequency and Wideband Modulation Arraying

    NASA Technical Reports Server (NTRS)

    Brockman, M. H.

    1984-01-01

    Summing network receives coherent signals from all receivers in array. Method sums narrow-band radio-frequency (RF) carrier powers and wide-band spectrum powers of array of separate antenna/receiver systems designed for phase-locked-loop or suppressed-carrier operation.

  8. Robust ML wideband beamformingin reverberant fields

    Microsoft Academic Search

    Elio D. Di Claudio; Raffaele Parisi

    2003-01-01

    Adaptive beamforming of sensor arrays immersed into reverberant fields can easily result in the cancellation of the useful signal because of the temporal correlation existing among the direct and the reflected path signals. Wideband beamforming can somewhat mitigate this phenomenon, but adaptive solutions based on the minimum variance (MV) criterion remain nonrobust in many practical applications, such as multimedia systems,

  9. Wideband Reflectance in Neonatal Intensive Care Units

    E-print Network

    Allen, Jont

    Wideband Reflectance in Neonatal Intensive Care Units DOI: 10.3766/jaaa.19.5.4 Navid Shahnaz in neonatal intensive care unit (NICU) babies, who have significantly higher incidence of otitis media it could improve hearing assessment in newborns. Methods: Thirty-one neonatal intensive care unit (NICU

  10. A novel wideband 140 GHz gyrotron amplifier

    E-print Network

    Joye, Colin D., 1980-

    2008-01-01

    The theory, design and experimental results of a wideband 140 GHz, 1 kW pulsed gyro-traveling wave amplifier are presented. The gyro- TWA operates in the HE(0,6) mode of a novel cylindrical confocal waveguide using a ...

  11. Designing Low Cost Wideband Microstrip Bandpass Filters

    Microsoft Academic Search

    Cornelis Jan Kikkert

    2005-01-01

    The design of RF filters where the bandwidth is much greater than 10% of the centre frequency is difficult to implement, since conventional filter design techniques such as those for coupled line or interdigital filters are applicable to filters with less than 10% bandwidth. This paper describes a design technique for designing wideband RF filters and illustrates this with the

  12. Compact wideband multiple conductor monopole antenna

    NASA Astrophysics Data System (ADS)

    Royce, R. K.

    1984-08-01

    A wideband trap-loaded monopole antenna having small structural dimensions in a plane normal to the polarization axis. The traps are resistively-terminated quarter wavelength transmission lines. The locations and anti-resonant frequencies of the traps are selected to make the antenna's input impedance and gain nominally uniform parameters with respect to frequency.

  13. Ultra Wide Band Planar Slot Antenna

    Microsoft Academic Search

    S. Noghanian; M. K. Jung

    2008-01-01

    In this paper a set of compact planar slot antennas for ultra wide band applications are presented. These antennas provide bandwidth of more than 7 GHz and are designed for microwave imaging and wireless communication applications for frequency range of 3–10 GHz. Both simulated and measured results are presented.

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

    PubMed

    Pan, Shilong; Yao, Jianping

    2011-12-12

    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

  15. Wideband two-dimensional and multiple beam phased arrays and microwave applications using piezoelectric transducers

    E-print Network

    Kim, Sang Gyu

    2005-08-29

    to achieve wideband performance. Very wideband performance can be achieved using an antipodal tapered slot antenna because of its inherent simple wideband transition from microstrip line to parallel-strip line. An antipodal tapered slot antenna and a phased...

  16. R. A. Scholtz University of Southern California UltRa Lab Ultra-Wideband Radio

    E-print Network

    Southern California, University of

    OneWayAttenuation(dB) Kevlar Sheet Polyethylene Paper Towel (Dry) Fiberglass Insul. concrete block painted 2x6 board 3/4"plywood 3/4" pine board wet paper towel glass drywall asphalt shingle kevlar, polystyrene dry paper to

  17. Wideband aperture array using RF channelizers and massively parallel digital 2D IIR filterbank

    NASA Astrophysics Data System (ADS)

    Sengupta, Arindam; Madanayake, Arjuna; Gómez-García, Roberto; Engeberg, Erik D.

    2014-05-01

    Wideband receive-mode beamforming applications in wireless location, electronically-scanned antennas for radar, RF sensing, microwave imaging and wireless communications require digital aperture arrays that offer a relatively constant far-field beam over several octaves of bandwidth. Several beamforming schemes including the well-known true time-delay and the phased array beamformers have been realized using either finite impulse response (FIR) or fast Fourier transform (FFT) digital filter-sum based techniques. These beamforming algorithms offer the desired selectivity at the cost of a high computational complexity and frequency-dependant far-field array patterns. A novel approach to receiver beamforming is the use of massively parallel 2-D infinite impulse response (IIR) fan filterbanks for the synthesis of relatively frequency independent RF beams at an order of magnitude lower multiplier complexity compared to FFT or FIR filter based conventional algorithms. The 2-D IIR filterbanks demand fast digital processing that can support several octaves of RF bandwidth, fast analog-to-digital converters (ADCs) for RF-to-bits type direct conversion of wideband antenna element signals. Fast digital implementation platforms that can realize high-precision recursive filter structures necessary for real-time beamforming, at RF radio bandwidths, are also desired. We propose a novel technique that combines a passive RF channelizer, multichannel ADC technology, and single-phase massively parallel 2-D IIR digital fan filterbanks, realized at low complexity using FPGA and/or ASIC technology. There exists native support for a larger bandwidth than the maximum clock frequency of the digital implementation technology. We also strive to achieve More-than-Moore throughput by processing a wideband RF signal having content with N-fold (B = N Fclk/2) bandwidth compared to the maximum clock frequency Fclk Hz of the digital VLSI platform under consideration. Such increase in bandwidth is achieved without use of polyphase signal processing or time-interleaved ADC methods. That is, all digital processors operate at the same Fclk clock frequency without phasing, while wideband operation is achieved by sub-sampling of narrower sub-bands at the the RF channelizer outputs.

  18. A 255 MHz Programmable Gain Amplifier and Low-Pass Filter for Ultra Low Power Impulse-Radio UWB Receivers

    Microsoft Academic Search

    Stefano D'Amico; Marco De Blasi; Marcello De Matteis; Andrea Baschirotto

    2012-01-01

    A 90 nm-CMOS power-optimized analog baseband chain for ultra-low-power impulse-radio ultra-wideband (IR-UWB) receivers is presented. The proposed device merges the functions of a programmable gain amplifier (PGA) and a low-pass filter (LPF). It consists of the cascade of three biquadratic cells made up by opamps in a series-shunt configuration, which features high input impedance, low load effects in the cascade

  19. A sub-100nA power management system for wireless structure health monitoring applications

    Microsoft Academic Search

    Zhangcai Huang; Yasuaki Inoue

    2011-01-01

    Recently, the power management becomes signif- icantly important for the ultra power wireless sensor node powered by energy harvesting devices. In this paper, a power management system from battery to wireless sensor node is proposed for wireless structure health monitoring applications. By using the proposed circuits, the power supply of a sensor network node is switched on only when some

  20. Robust Packet Detector based Automatic Gain Control Algorithm for OFDM-based Ultra-WideBand systems

    E-print Network

    Hung, Shih-Hao

    Baseband Front End Signal from RF Fig.1 Block diagram of the AGC system. Therefore, the power spectral an robust PD for UWB system in [3][4]. The SNR of received preamble signal can be enhanced by the proposed Corporation ABSTRACT We propose a robust auto gain control (AGC) algorithm for OFDM-based ultra-wideband (UWB

  1. Design of a Wideband Radio Telescope

    Microsoft Academic Search

    W. A. Imbriale; S. Weinreb; H. Mani

    2007-01-01

    A wideband Radio Telescope is being designed for use in the Goldstone Apple Valley Radio Telescope program. It uses an existing 34-meter antenna retrofitted with a tertiary offset mirror placed at the apex of the main reflector. It can be rotated to use two feeds that cover the 1.2 to 14 GHz band. The feed for 4.0 to 14.0 GHz

  2. Wideband Hyperspectral Imaging for Space Situational Awareness

    Microsoft Academic Search

    Ian S. Robinson; A. Klier

    2006-01-01

    Wideband hyperspectral imaging (WHSI) systems collect simultaneous spectral and spatial imagery across a broad spectrum that includes the visible\\/near infrared (VNIR), short-wave infrared (SWIR), mid-wave infrared (MWIR), and long-wave infrared (LWIR) regimes. These passive optical systems capture reflected sunlight and thermal emissions from targets enabling the characterization of surface material, thermal properties, propellants, and gaseous emissions when targets are sunlit

  3. A distributed bidirectional wideband MIMO channel souder

    Microsoft Academic Search

    Nianzu Zhang; Haiming Wang; Wei Hong; Jianyi Zhou; Guangqi Yang; Hui Zhang; Chen Yu; Zhenqi Kuai

    2012-01-01

    In this paper, we present a wideband distributed bidirectional multiple-input — multiple-output (MIMO) channel sounder. It is developed for characterizing up to 4×4 MIMO channel in four frequency bands from 2GHz to 15GHz with 100MHz bandwidth. To fully understand the dynamic characteristics of multilink MIMO, such as distributed and cooperative MIMO, the radio over fiber (RoF) techniques is adopted. Furthermore,

  4. Wideband channel model for aeronautical telemetry

    Microsoft Academic Search

    MICHAEL RICE; A. Davis; CHRISTIAN BETTWEISER

    2004-01-01

    A multipath channel model for wideband aeronautical telemetry links is presented. Channel sounding data were collected at Edwards AFB, CA, at both L-band and lower S-band. Frequency domain analysis techniques were used to evaluate candidate channel models. The channel model is composed of three propagation paths: a line-of-sight direct path and two specular reflections. The first specular reflection is characterized

  5. Removal of RFI in wideband radars

    Microsoft Academic Search

    C. T. C. Le; S. Hensley; E. Chapin

    1998-01-01

    The least-mean-square (LMS) adaptive filter is applied to suppress narrow-band radiofrequency interference (RFI) in wideband synthetic aperture radar (SAR) signals. Simulation is used to show the working principles of the adaptive filter and to obtain the optimum filter's parameters. The algorithm is tested with P-band synthetic aperture radar (SAR) data collected by the NASA\\/JPL airborne SAR (AIRSAR) in different noisy

  6. Node Position Discovery in Wireless Sensor M. Onur Ergin

    E-print Network

    Wichmann, Felix

    and allowance of frequency diversity of high frequency radio (CC2420) that is frequently used in wireless sensor of the sensor nodes, such as radio frequency(RF) ranging, acoustic ranging, ultra-wide band sig- nal rangingNode Position Discovery in Wireless Sensor Networks M. Onur Ergin Telecommunication Networks Group

  7. Wideband Waveform Optimization with Energy Detector Receiver in Cognitive Radio

    E-print Network

    Qiu, Robert Caiming

    Wideband Waveform Optimization with Energy Detector Receiver in Cognitive Radio Zhen Hu Department investigates the transmitted waveform optimization issues for wideband cognitive radio with energy detector receiver. The motivation is to provide a cheap cognitive radio network with simple and cheap cognitive

  8. Wideband heterodyne spatial tracking for optical space communications

    Microsoft Academic Search

    D. J. Bernays; Gary M. Carter; Kim A. Winick

    1992-01-01

    A wideband optical heterodyne spatial tracker for use in diode laser-based heterodyne optical space communications is described. The tracking error signals are formed by correlating the output of an intensity noise-cancelling communications receiver with the outputs of the tracking photodetectors. This correlation technique removes noise induced offsets which may significantly limit performance of other wideband tracking schemes and is an

  9. Wideband heterodyne spatial tracking for optical space communications

    Microsoft Academic Search

    D. J. Bernays; G. M. Carter; K. A. Winick

    1991-01-01

    A wideband optical heterodyne spatial tracker for use in diode laser-based heterodyne optical space communications is described. The tracking error signals are formed by correlating the output of an intensity noise-cancelling communications receiver with the outputs of the tracking photodetectors. This correlation technique removes noise induced offsets which may significantly limit performance of other wideband tracking schemes and is an

  10. Wideband enhancement of television images for people with visual impairments

    E-print Network

    Peli, Eli

    Wideband enhancement of television images for people with visual impairments Eli Peli The Schepens; accepted January 23, 2004 Wideband enhancement was implemented by detecting visually relevant edge and bar distinguish the enhanced images and preferred them over the original images (and degraded images). Most

  11. Wafer Probe Station, Low Noise Amplifiers, and Wideband Feed Developments

    E-print Network

    Weinreb, Sander

    Wafer Probe Station, Low Noise Amplifiers, and Wideband Feed Developments S. Weinreb, A. Akgiray-ridge flared horn wideband feeds #12;Wafer Fabrication of LNA's and Other Radiometer Components 20-Sep-2011 of Millions Field Environment Phased- Array Feeds 0.7-1.8 15K/50K 300K 800,000 Noise SKA Mid 15m Dishes 0

  12. Rayleigh fading effect reduction with wideband DS\\/CDMA signals

    Microsoft Academic Search

    Jack M. Holtzman; L. M. A. Jalloul

    1991-01-01

    The authors present an analysis of the mitigation of the Rayleigh fading effect for wideband direct sequence pseudonoise signaling. The reduction of the Rayleigh fading effect is an advantage of code division multiple access (CDMA) over narrowband transmission systems and it eases the burden of CDMA power control. A general expression for the standard deviation of the received wideband signal

  13. Towards fully integrated wideband transceivers: fundamental challenges, solutions and future

    Microsoft Academic Search

    Sudipto Chakraborty; N. R. Belk; A. Batra; M. Goel; A. Dabak

    2005-01-01

    Design considerations of a generic wideband communication system differ significantly from its narrowband counterpart. In a wideband system, intermodulation distortion increases significantly, as the signal propagates through various active stages of RF\\/analog signal processing blocks. Thus, in contrary to the narrowband approach, it requires careful optimization of noise and linearity for a given power consumption. Many of these systems today

  14. An ultra-compact and efficient Li-ion battery charger circuit for biomedical applications

    E-print Network

    Do Valle, Bruno Guimaraes

    This paper describes an ultra-compact analog lithium-ion (Li-ion) battery charger for wirelessly powered implantable medical devices. The charger presented here takes advantage of the tanh output current profile of an ...

  15. Dual-Vivaldi wideband nanoantenna with high radiation efficiency over the infrared frequency band.

    PubMed

    Iluz, Zeev; Boag, Amir

    2011-08-01

    A dual-Vivaldi nanoantenna is proposed to demonstrate the possibility of wideband operation at IR frequencies. The antenna geometry design is guided by the material properties of metals at IR frequencies. According to our numerical results, this nanoantenna has both high radiation efficiency and good impedance-matching properties over a wide frequency band (more than 122%) in the IR frequency band. The design is based on the well-known Vivaldi antenna placed on quartz substrate but operating as a pair instead of a single element. Such a pair of Vivaldi antennas oriented in opposite directions produces the main lobe in the broadside direction (normal to the axes of the antennas) rather than the usual peak gain along the axis (end fire) of a single Vivaldi antenna. The dual-Vivaldi nanoantenna is easy to fabricate in a conventional electron-beam lithography process, and it provides a large number of degrees of freedom, facilitating design for ultra-wideband operation. PMID:21808308

  16. Ultra Wide Band ULTRA WIDE BAND

    E-print Network

    Dobigeon, Nicolas

    Ultra Wide Band ULTRA WIDE BAND Martial COULON ENSEEIHT - 3 ann´ee T´el´ecom-R´eseaux - option Mobilit´e ann´ee 2007-2008 1/ 108 #12;Ultra Wide Band Plan du cours Introduction D´efinition Historique et;Ultra Wide Band Plan du cours Introduction D´efinition Historique et R´eglementations Applications Sp

  17. Adaptive antenna array transmit diversity in FDD forwad link for W-CDMA and broadband packet wireless access

    Microsoft Academic Search

    HIDEKAZU TAOKA; SHINYA TANAKA; TAISUKE IHARA; M. Sawahashi

    2002-01-01

    This article presents a transmitter antenna weight generation method in adaptive antenna array transmit diversity (AAA-TD) that focuses on the calibrations in wideband direct sequence codedivision multiple access (W-CSDMA) and broadband packet wireless access in FDD systems. In our scheme, the adaptively generated receiver antenna weights of the reverse link in the coherent adaptive antenna array diversity receiver are used

  18. Wideband perfect coherent absorber based on white-light cavity

    NASA Astrophysics Data System (ADS)

    Kotlicki, Omer; Scheuer, Jacob

    2015-03-01

    Coherent Perfect Absorbers (CPAs) are optical cavities which can be described as time-reversed lasers where light waves that enter the cavity, coherently interfere and react with the intra-cavity losses to yield perfect absorption. In contrast to lasers, which benefit from high coherency and narrow spectral linewidths, for absorbers these properties are often undesirable as absorption at a single frequency is highly susceptible to spectral noise and inappropriate for most practical applications. Recently, a new class of cavities, characterized by a spectrally wide resonance has been proposed. Such resonators, often referred to as White Light Cavities (WLCs), include an intra-cavity superluminal phase element, designed to provide a phase response with a slope that is opposite in sign and equal in magnitude to that of light propagation through the empty cavity. Consequently, the resonance phase condition in WLCs is satisfied over a band of frequencies providing a spectrally wide resonance. WLCs have drawn much attention due to their attractiveness for various applications such as ultra-sensitive sensors and optical buffering components. Nevertheless, WLCs exhibit inherent losses that are often undesirable. Here we introduce a simple wideband CPA device that is based on the WLC concept along with a complete analytical analysis. We present analytical and FDTD simulations of a practical, highly compact (12µm), Silicon based WLC-CPA that exhibits a flat and wide absorption profile (40nm) and demonstrate its usefulness as an optical pulse terminator (>35db isolation) and an all optical modulator that span the entire C-Band and exhibit high immunity to spectral noise.

  19. IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION, VOL. 53, NO. 7, JULY 2005 2185 A Compact Antenna for Ultrawide-Band Applications

    E-print Network

    Sarabandi, Kamal

    ) antennas. I. INTRODUCTION Afew decades after the early investigations on ultra- wide-band (UWB) wireless with wide-band impedance matched characteristics. Traveling wave antennas and antennas with topologies.1109/TAP.2005.850750 technique for designing wide-band antennas is to use multires- onant radiating

  20. Description The coplanar PICA (Planar Inverted Cone Antenna) is a novel and compact

    E-print Network

    Beex, A. A. "Louis"

    in UWB applications. Coplanar PICA Antenna Features and application · Compact and planar geometry printed on substrate · Wideband omni-directional pattern · UWB applications · Wideband wireless communicationsDescription The coplanar PICA (Planar Inverted Cone Antenna) is a novel and compact ultra wideband

  1. Wideband infrared receiver backend. [Doppler radar, radiometers

    NASA Technical Reports Server (NTRS)

    Flattau, T.; Mellars, J.

    1974-01-01

    The design, operation, and configuration of the receiver backend for a wideband infrared tracking receiver are described. A squaring loop is incorporated into the receiver design to enable it to track the Doppler shifted carrier which is Phase Shift Keyed modulated. The receiver has a 400 MHz instantaneous bandwidth and tracks signals whose carrier frequency at the backend input is between 200 and 900 MHz with frequency variation rates greater than 20 MHz/second. The output data is compatible with MECL 3 logic.

  2. Miniature biotelemeter gives multichannel wideband biomedical data

    NASA Technical Reports Server (NTRS)

    Carraway, J. B.

    1972-01-01

    A miniature biotelemeter was developed for sensing and transmitting multiple channels of biomedical data over a radio link. The design of this miniature, 10-channel, wideband (5 kHz/channel), pulse amplitude modulation/ frequency modulation biotelemeter takes advantage of modern device technology (e.g., integrated circuit operational amplifiers, complementary symmetry/metal oxide semiconductor logic, and solid state switches) and hybrid packaging techniques. The telemeter is being used to monitor 10 channels of neuron firings from specific regions of the brain in rats implanted with chronic electrodes. Design, fabrication, and testing of an engineering model biotelemeter are described.

  3. IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS, VOL. 4, NO. 6, NOVEMBER 2005 2939 Error Performance of Pulse-Based

    E-print Network

    Qiu, Robert Caiming

    . INTRODUCTION ULTRA-WIDEBAND (UWB) [1]­[8] has attracted signif- icant academic and commercial interest because with additive white Gaussian noise (AWGN) was studied by simulations. In [15], a UWB multiple-antenna]. Major applications of UWB are likely to be for indoor environments for which the channel amplitude

  4. IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS, VOL. 6, NO. 6, JUNE 2007 1 An Effective Resource Management Scheme for

    E-print Network

    Shen, Xuemin "Sherman"

    . pseudorandom sequence design and effective call admission control (CAC). In such a multi-channel case, two the superior performance of our proposed scheme. Index Terms-- Admission control, ultra-wideband (UWB), quality and control, industrial maintenance, medical imaging, sensor networks, as well as Department of Defense (Do

  5. Impact of Multipath Interference on the Performance of an UWB Fast Acquisition System for Ranging in an Indoor Wireless Channel

    Microsoft Academic Search

    Yassine Salih Alj; Charles L. Despins; Sofiène Affes

    2008-01-01

    In this paper, the effects of multipath interferences on the performance of a multiuser ultra-wideband (UWB) fast acquisition system operating in an underground indoor fading channel are evaluated and compared. Various pulse shapes are considered with different scenarios of interference and Gaussian noise in extensive Monte-Carlo simulations. The results show the 6 order Gaussian derivative as the most suitable pulse

  6. Infoseek Ultra

    NSDL National Science Digital Library

    Infoseek Corp. has released a Beta version of its new Ultra search engine. It supports Boolean AND/OR/NOT, phrase, case sensitive, and field searching, and supplies relevance feedback with results. It has indexed over 50 million web pages, and claims to make your web page available in its database immediately on submission. It also claims to be the first real-time index of the Internet (through real-time indexing by its spider technology).

  7. Wideband Low-Profile Antenna Arrays: Fundamental Limits and Practical Implementations

    NASA Astrophysics Data System (ADS)

    Doane, Jonathan

    Advanced wireless communication and sensing systems have created a growing need for high performance, compact antennas. Low-profile wideband phased arrays are of particular interest, and have recently been shown to be capable of extremely large bandwidths. However, the size, weight, and cost of phased arrays still makes them impractical for many applications. The development of thinner, lightweight, and inexpensive wideband arrays is critical to improving the capabilities of small platforms such as small unmanned aerial vehicles. Like all antennas, phased arrays are limited by a fundamental compromise between size and performance. Although the theoretical limitations of electrically small antennas have been well known for over 60 years, similarly general limits have not yet been developed for periodic antenna arrays. In the first part of this thesis, we derive a new fundamental bandwidth limit for any periodic array that is backed by a conducting ground plane and constructed from passive and reciprocal materials. This limit is related to several critical design factors, including the array's thickness, polarization, scan angle, materials used, as well as the overall complexity of the array design. We also consider the common case when all radiating currents are confined to a thin planar sheet placed above the ground plane. We show here that such planar phased arrays have a fundamental impedance bandwidth limit of 8.3:1 (with VSWR ?2:1), in the absence of material loading. This bandwidth may be further improved by adding dielectric superstrate or magnetic substrate material layers. Knowledge of such fundamental bandwidth limits is extremely useful in the design of practical wideband arrays, which is the focus of the second part of this thesis. A key challenge with many wideband arrays is developing a feed circuit that supports extremely wide bandwidths without significantly adding to the size, weight, and cost of the design. Here, we demonstrate a novel approach that overcomes this problem by exploiting the natural reactance of the feed circuit as a simple impedance matching network for the array. The result is a simultaneous reduction in size and weight and improvement in bandwidth compared to other feeding techniques. We refer to our design as the Tightly Coupled Dipole Array with Integrated Balun (TCDA-IB), and it achieves 7.35:1 bandwidth while maintaining a low VSWR of ? 2.65:1 while scanning to +/- 45° in all planes. A prototype 8x8 array was constructed and demonstrated excellent performance relative to simulation. We also demonstrate that by adding reconfigurable components to the TCDA-IB, its maximum scan angle may by increased to as much as +/- 70° while maintaining a 5:1 impedance bandwidth. Our fundamental bandwidth limits reveal for the first time the extent of the realizable design space for wideband low-profile arrays, and suggest there are significant opportunities for further improvement. Several practical techniques are also presented for increasing bandwidth and scanning performance while reducing the total size, weight and cost of the array. In summary, the ongoing development of high-performance wideband low-profile arrays will likely remain an important and fertile area of research for the foreseeable future.

  8. A new CPW-fed slot antenna for ultra-wide band application

    Microsoft Academic Search

    M. Ali; Y. Hu; A. T. M. Sayem; R. Usaha

    2005-01-01

    A new design of a coplanar waveguide (CPW)-fed folded slot antenna is presented which is suitable for ultra-wide band application. Antenna impedance and bandwidth are studied as function of slot parameters, substrate dielectric constant, and substrate thickness. Wideband operation is achieved by designing an adjacent semicircular slot to a folded slot antenna. A prototype antenna was fabricated on RO4003 (?r

  9. Wide-Band Source Localization in the Alpha-Stable In this chapter, we study the problem of localizing wide-band sources in the presence of

    E-print Network

    Tsakalides, Panagiotis

    the problem of localizing wide-band sources in the presence of noise modeled as a complex isotropic stable to the localization problem of narrow-band sources in the presence of noise modeled as a complex isotropic Cauchy of wide-band sources in impulsive noise environments. Focused wide-band methods are used so that broad

  10. Solving Autonomy Technology Gaps through Wireless Technology and Orion Avionics Architectural Principles

    NASA Astrophysics Data System (ADS)

    Black, Randy; Bai, Haowei; Michalicek, Andrew; Shelton, Blaine; Villela, Mark

    2008-01-01

    Currently, autonomy in space applications is limited by a variety of technology gaps. Innovative application of wireless technology and avionics architectural principles drawn from the Orion crew exploration vehicle provide solutions for several of these gaps. The Vision for Space Exploration envisions extensive use of autonomous systems. Economic realities preclude continuing the level of operator support currently required of autonomous systems in space. In order to decrease the number of operators, more autonomy must be afforded to automated systems. However, certification authorities have been notoriously reluctant to certify autonomous software in the presence of humans or when costly missions may be jeopardized. The Orion avionics architecture, drawn from advanced commercial aircraft avionics, is based upon several architectural principles including partitioning in software. Robust software partitioning provides "brick wall" separation between software applications executing on a single processor, along with controlled data movement between applications. Taking advantage of these attributes, non-deterministic applications can be placed in one partition and a "Safety" application created in a separate partition. This "Safety" partition can track the position of astronauts or critical equipment and prevent any unsafe command from executing. Only the Safety partition need be certified to a human rated level. As a proof-of-concept demonstration, Honeywell has teamed with the Ultra WideBand (UWB) Working Group at NASA Johnson Space Center to provide tracking of humans, autonomous systems, and critical equipment. Using UWB the NASA team can determine positioning to within less than one inch resolution, allowing a Safety partition to halt operation of autonomous systems in the event that an unplanned collision is imminent. Another challenge facing autonomous systems is the coordination of multiple autonomous agents. Current approaches address the issue as one of networking and coordination of multiple independent units, each with its own mission. As a proof-of-concept Honeywell is developing and testing various algorithms that lead to a deterministic, fault tolerant, reliable wireless backplane. Just as advanced avionics systems control several subsystems, actuators, sensors, displays, etc.; a single "master" autonomous agent (or base station computer) could control multiple autonomous systems. The problem is simplified to controlling a flexible body consisting of several sensors and actuators, rather than one of coordinating multiple independent units. By filling technology gaps associated with space based autonomous system, wireless technology and Orion architectural principles provide the means for decreasing operational costs and simplifying problems associated with collaboration of multiple autonomous systems.

  11. Capacity of Sparse Wideband Channels with Partial Channel Feedback

    E-print Network

    Sayeed, Akbar M.

    Raghavan and Akbar M. Sayeed Abstract This paper studies the ergodic capacity of wideband multipath@ieee.org). A. M. Sayeed is with the Department of Electrical and Computer Engineering, University of Wisconsin

  12. Energy Savings by Wideband Temperature Control in Telephone Offices

    E-print Network

    Lingousky, J. E.; McKay, J. R.

    1983-01-01

    -effective measure for reducing such energy use has been Wideband Temperature Control which provides no heating, cooling or fan operation between 65 F and 80 F, except for special equipment or ventilation requirements. Building energy load and use programs...

  13. Wideband micromachined microphones with radio frequency detection

    NASA Astrophysics Data System (ADS)

    Hansen, Sean Thomas

    There are many commercial, scientific, and military applications for miniature wideband acoustic sensors, including monitoring the condition or wear of equipment, collecting scientific data, and identifying and localizing military targets. The application of semiconductor micromachining techniques to sensor fabrication has the potential to transform acoustic sensing with small, reproducible, and inexpensive silicon-based microphones. However, such sensors usually suffer from limited bandwidth and from non-uniformities in their frequency response due to squeeze-film damping effects and narrow air gaps. Furthermore, they may be too fragile to be left unattended in a humid or dusty outdoor environment. Silicon microphones that incorporate capacitive micromachined ultrasonic transducer membranes overcome some of the drawbacks of conventional microphones. These micromachined membranes are small and robust enough to be vacuum-sealed, and can withstand atmospheric pressure and submersion in water. In addition, the membrane mechanical response is flat from dc up to ultrasonic frequencies, resulting in a wideband sensor for accurate spectral analysis of acoustic signals. However, a sensitive detection scheme is necessary to detect the small changes in membrane displacement that result from using smaller, stiffer membranes than do conventional microphones. We propose a radio frequency detection technique, in which the capacitive membranes are incorporated into a transmission line. Variations in membrane capacitance due to impinging sound pressure are sensed through the phase variations of a carrier signal that propagates along the line. This dissertation examines the design, fabrication, modeling, and experimental measurements of wideband micromachined microphones using sealed ultrasonic membranes and RF detection. Measurements of fabricated microphones demonstrate less than 0.5 dB variation in their output responses between 0.1 Hz to 100 kHz under electrostatic actuation of the membranes. The measured equivalent noise level of a fabricated 3 mm by 3 mm sensor is 53.8 dB(A) SPL in the audio band using a simple phase detection circuit operating at 2.8 GHz. Because the vacuum-sealed membrane structure has a low mechanical noise floor, sensitivity may be improved with higher carrier frequencies and more sophisticated detection circuitry.

  14. Design of LTCC Wideband Patch Antenna for LMDS Band Applications

    Microsoft Academic Search

    Kuo-Sheng Chin; Ho-Ting Chang; Jia-An Liu

    2010-01-01

    This letter presents a wideband patch antenna on a low-temperature cofired ceramic substrate for Local Multipoint Distribution Service band applications. Conventional rectangular patch antennas have a narrow bandwidth. The proposed via-wall structure enhances the electric field coupling between the stacked patches to achieve wideband characteristics. We designed same-side and opposite-side feeding configurations and report on the fabrication of an experimental

  15. Wideband dual-polarized patch antenna array on finite cylinder

    Microsoft Academic Search

    H. W. Lai; C. L. Mak; K. M. Luk

    2004-01-01

    A wideband dual-polarized patch antenna array on a finite conducting cylinder is investigated. By employing the L-probe coupling technique and phase cancellation technique together with two vertical sidewalls, a wideband dual-polarized array with high isolation (S12 < -32 dB, 1.85-2.24 GHz) is fabricated and tested. The proposed antenna is suitable for various mobile communication applications, including smart antenna and MIMO

  16. Wideband source modeling and localization: a HOS-based approach

    Microsoft Academic Search

    S. Shamsunder; G. B. Giannakis

    1991-01-01

    A polyspectra-based solution to the nonparametric multichannel system identification problem is proposed. As an application, the problems of wideband source bearing estimation an identification are considered. Simultaneous detection and parameter estimation of wideband sources arriving at a sensor array are performed using higher-order statistics. Source detection and consistent parameter estimation are approached via a polyspectra-based information theoretic criterion. The proposed

  17. Experimental Results on Multiple-Input Single-Output (MISO) Time Reversal for UWB

    E-print Network

    Qiu, Robert Caiming

    with multiple-input single- output (MISO) antennas over ultra-wideband (UWB) channels. In particular, temporal ULtra-wideband (UWB) transmission has recently re- ceived significant attention in both academia and in- dustry for applications in short to medium range wireless communications [1] [2] [3]. UWB techniques have

  18. ION GNSS 2009 Savannah, GA, 22-25 Sept, Session B4

    E-print Network

    Calgary, University of

    positioning with terrestrial technologies such as ultra wideband (UWB) and wireless local area networks (WLAN (UWB) ranging systems with a GNSS receiver/antenna to provide a high precision surveying system, a method to augment the system under sub-optimal signal conditions is required. Ultra wideband (UWB), very

  19. Design of a Wideband Radio Telescope

    NASA Technical Reports Server (NTRS)

    Imbriale, William A.; Weinreb, Sander; Mani, Handi

    2007-01-01

    A wideband Radio Telescope is being designed for use in the Goldstone Apple Valley Radio Telescope program. It uses an existing 34-meter antenna retrofitted with a tertiary offset mirror placed at the apex of the main reflector. It can be rotated to use two feeds that cover the 1.2 to 14 GHz band. The feed for 4.0 to 14.0 GHz is a cryogenically cooled commercially available open boundary quadridge horn from ETS-Lindgren. Coverage from 1.2 to 4.0 GHz is provided by an un-cooled scaled version of the same feed. The performance is greater than 40% over most of the band and greater than 55%from 6 to 13.5 GHz.

  20. IEEE MICROWAVE AND WIRELESS COMPONENTS LETTERS, VOL. 19, NO. 6, JUNE 2009 407 A 0.15 GHz Cryogenic SiGe MMIC LNA

    E-print Network

    Weinreb, Sander

    IEEE MICROWAVE AND WIRELESS COMPONENTS LETTERS, VOL. 19, NO. 6, JUNE 2009 407 A 0.1­5 GHz Cryogenic for operation at cryogenic temperatures is presented. At room temperature, the cir- cuit provides greater than and the first matched wideband cryogenic integrated circuit LNA that covers frequencies as low as 0.1 GHz. Index