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1

Satellite radio  

Microsoft Academic Search

Satellites have been a highly effective platform for multi-form broadcasts. This has led to a revival of the radio era. The\\u000a satellite radio is a natural choice to bridge the digital gap. It has several novel features like selective addressing and\\u000a error control. The value-added services from such systems are of particular interest.

S. Rangarajan

2002-01-01

2

Radio determination satellite service  

Microsoft Academic Search

The capabilities and measured performance of a geosynchronous satellite-based service called the radio determination satellite service (RDSS), which operates at radio frequencies allocated by the International Telecommunications Union (ITU) and is licensed in the United States by the Federal Communications Commission (FCC), are discussed. Plans for both improvement in capability and expansion to nearly global coverage are described. Since RDSS

Robert D. Briskman

1990-01-01

3

Amateur Radio Satellite Communications.  

ERIC Educational Resources Information Center

The Amateur Radio Satellite Communications project had, as its goal, the assembly of an amateur radio satellite station in a high school physics classroom. Specific objectives were to provide: (1) a special source of interest as a motivator for attracting students and building public relations; (2) a center of interest as a motivator for the study…

Koch, David P.

4

Direct Broadcast Satellite: Radio Program  

Microsoft Academic Search

NASA is committed to providing technology development that leads to the introduction of new commercial applications for communications satellites. The Direct Broadcast Satellite-Radio (DBS-R) Program is a joint effort between The National Aeronautics and Space Administration (NASA) and The United States Information Agency\\/Voice of America (USIA\\/VOA) directed at this objective. The purpose of this program is to define the service

James E. Hollansworth

1992-01-01

5

Direct Broadcast Satellite: Radio Program  

NASA Technical Reports Server (NTRS)

NASA is committed to providing technology development that leads to the introduction of new commercial applications for communications satellites. The Direct Broadcast Satellite-Radio (DBS-R) Program is a joint effort between The National Aeronautics and Space Administration (NASA) and The United States Information Agency/Voice of America (USIA/VOA) directed at this objective. The purpose of this program is to define the service and develop the technology for a direct-to-listener satellite sound broadcasting system. The DBS-R Program, as structured by NASA and VOA, is now a three-phase program designed to help the U.S. commercial communications satellite and receiver industry bring about this new communications service. Major efforts are being directed towards frequency planning hardware and service development, service demonstration, and experimentation with new satellite and receiver technology.

Hollansworth, James E.

1992-01-01

6

Sirius Satellite Radio: Radio entertainment in the sky  

Microsoft Academic Search

Satellite broadcasting of radio programs is an effective means of serving large and distributed markets. A space-based radio system can provide about 100 high quality music, voice, and data channels to users spread over a vast geographic area. Employing digital technology and an elaborate system design, this approach significantly outperforms traditional AM and FM radio broadcasting in signal quality, program

F. Davarian

2002-01-01

7

Australian Broadcasting Corporation Online: Radio National  

NSDL National Science Digital Library

The highlights of this Australian Broadcasting Corporation site are transcripts of radio shows in the areas of health, law, religion, sports, and current affairs. Also included are transcripts of Ockham's Razor, a show covering many different topics in which one "thoughtful [person] has [his or her] say without pesky interviewers interrupting." Time coverage varies, with some shows' transcripts dating back to 1995. The site also contains other program and pertinent information about this network, on the air since 1932.

1997-01-01

8

Studies in radio effectiveness by the Psychological Corporation  

Microsoft Academic Search

The studies of the Psychological Corporation relative to radio are summarized. They deal with the effectiveness versus the popularity of programs, the sales effectiveness of radio programs, the relative effectiveness of radio over other advertising media, panel studies of radio programs, the effectiveness of educational broadcasts, station popularity, and a comparison of methods for measuring the size of radio audiences.

H. C. Link; P. G. Corby

1940-01-01

9

Towards Generic Satellite Payloads: Software Radio  

Microsoft Academic Search

Satellite payloads are becoming much more complex with the evolution towards multimedia applications. Moreover satellite lifetime increases while standard and services evolve faster, necessitating a hardware platform that can evolves for not developing new systems on each change. The same problem occurs in terrestrial systems like mobile networks and a foreseen solution is the software defined radio technology. In this

Catherine Morlet; Marie-laure Boucheret; Vencent Calmettes; Béatrice Paillassa; Tanguy Pérennou

2003-01-01

10

Satellite Radio Adoption Demand: Consumer Beliefs, Attitudes and Intentions  

Microsoft Academic Search

Subscription-based satellite radio services altered the economic fundamentals of the radio industry. To better understand the reasons behind radio audience adoption of satellite radio, this study examines the adoption process by exploring audience beliefs, perceptions, attitudes and intentions, in addition to economic and situational factors. Data were collected via a national telephone survey of radio listeners. The results are discussed

Carolyn A. Lin

2010-01-01

11

Packet radio in the amateur satellite service  

Microsoft Academic Search

A review of the satellite-based packet radio activities taking place in the Amateur Radio Service is presented. Five projects are discussed. The Digital Communications Experiment (DCE) on Uosat OSCAR-11 is a store-and-forward system that is accessed by a limited number of stations around the world designated as DCE gateways. These gateway stations retrieve and store messages forwarded to them via

Robert J. Diersing; Jeffrey W. Ward

1989-01-01

12

Packet radio in the Amateur Satellite Service  

Microsoft Academic Search

A review of the satellite-based packet radio activities taking place in the Amateur Radio Service is presented. Five projects are discussed. The Digital Communications Experiment (DCE) on UoSAT-OSCAR-11 is a store-and-forward system that is accessed by a limited number of stations around the world designated as DCE gateways. These gateway stations retrieve and store messages forwarded to them via terrestrial

ROBERT J. DIERSING; JEFFREY W. WARD

1989-01-01

13

The development of low-earth-orbit store-and-forward satellites in the Amateur Radio Service  

Microsoft Academic Search

The author discusses several satellites whose primary mission is to provide store-and-forward message relay services for radio amateurs. The primary focus is on the PACSAT-1 satellite owned and operated by the Radio Amateur Satellite Corporation of North America (AMSAT-NA), and the UoSAT-3 and UoSAT-5 satellites constructed and operated by the University of Surrey (England) UoSAT Spacecraft Engineering Research Unit. This

ROBERT J. DIERSING

1993-01-01

14

Sirius XM Satellite Radio system overview and services  

Microsoft Academic Search

Sirius XM Radio, through its Sirius and XM Satellite Radio systems, broadcasts continuous high quality audio, video and data content to over nineteen million subscribers throughout the Continental United States (CONUS) and Canada. The original Sirius system utilizes three satellites in highly inclined orbits. The original XM system utilizes two satellites in geostationary orbits. Both systems achieve a coverage pattern

Stefano DiPierro; Riza Akturan; Richard Michalski

2010-01-01

15

Protocol Design for Mobile Radio Group Communications Over Satellite  

Microsoft Academic Search

A protocol design for a mobile radio service supporting half-duplex push-to-talk voice communications over mobile satellite systems is presented. The service enables a closed group of mobile radio users to communicate among themselves, so that a transmission from any user is received by all. A key issue is the efficient utilization of satellite channels. Demand-assignment multiple access (DAMA) is employed

Victor C. M. Leung

1992-01-01

16

A multifunctional antenna for terrestrial and satellite radio applications  

Microsoft Academic Search

A multifunctional antenna is presented for the application in terrestrial radio services like GSM 900 MHz, DCS 1800 MHz as well as for satellite radio services like GPS 1575 MHz. At the terrestrial frequency bands GSM 900 MHz and DCS 1800 MHz the antenna exhibits omnidirectional radiation characteristics in horizontal plane for vertical polarized waves. At the frequency bands of

S. Lindenmeier; J. F. Luy; P. Russer

2001-01-01

17

Utilizing a TDRS satellite for direct broadcast satellite-radio propagation experiments and demonstrations  

Microsoft Academic Search

The NASA\\/VOA Direct Broadcast Satellite - Radio (DBS-R) Program will be using a NASA Tracking Data Relay Satellite (TDRS) satellite at 62 deg West longitude to conduct live satellite S-band propagation experiments and demonstrations of satellite sound broadcasting over the next two years (1993-1994). The NASA\\/VOA DBS-R program has applied intensive effort to garner domestic and international support for the

James E. Hollansworth

1993-01-01

18

Wave propagation and earth satellite radio emission studies  

NASA Technical Reports Server (NTRS)

Radio propagation studies of the ionosphere using satellite radio beacons are described. The ionosphere is known as a dispersive, inhomogeneous, irregular and sometimes even nonlinear medium. After traversing through the ionosphere the radio signal bears signatures of these characteristics. A study of these signatures will be helpful in two areas: (1) It will assist in learning the behavior of the medium, in this case the ionosphere. (2) It will provide information of the kind of signal characteristics and statistics to be expected for communication and navigational satellite systems that use the similar geometry.

Yeh, K. C.; Liu, C. H.; Flaherty, B. J.

1974-01-01

19

Satellite emission radio interferometric earth surveying series - GPS geodetic system  

NASA Technical Reports Server (NTRS)

A concept called SERIES (satellite emissions radio interferometric earth surveying) which makes use of GPS (global positioning system) radio transmissions without any satellite modifications, is described. Through the use of very long baseline interferometry (VLBI) and its calibration methods, 0.5 to 3 cm three dimensional baseline accuracy can be achieved over distances of 2 to 200 km respectively, with only 2 hours of on-site data acquisition. Attention is given to such areas as: the radio flux equivalent of GPS transmissions, synthesized delay precision, transmission and frequency subsystem requirements, tropospheric and ionospheric errors. Applications covered include geodesy and seismic tectonics.

Macdoran, P. F.

1979-01-01

20

Flexible satellites: software radio in the sky  

Microsoft Academic Search

Regenerative satellites with on-board processing offer great advantages for multimedia applications as they improve the global budget link and decrease the transfer delay when on-board packet switching is achieved. Meanwhile, they are often considered not flexible enough to follow evolution of services and transparent payload satellites are still used. This paper focuses on the introduction of flexibility at the satellite

B. Paillassa; C. Morlet

2003-01-01

21

Direct broadcast satellite-radio, space-segment\\/receiver tradeoffs  

Microsoft Academic Search

The balance between receiver complexity and the required satellite equivalent isotropically radiated power (EIRP) for Direct Broadcast Satellite-Radio (DBS-R) service is addressed. In general the required receiver complexity and cost can be reduced at the expense of higher space-segment cost by allowing a higher satellite EIRP. The tradeoff outcome is sensitive to the total number of anticipated receivers in a

Nasser Golshan

1993-01-01

22

Direct broadcast satellite service by direct broadcast satellite corporation  

Microsoft Academic Search

It is noted that common carrier operation implies the offer to transmit television programs or any other information in electronic form for any customer at a rate posted in a tariff recorded at the FCC and applied without discrimination. The satellite system developed must be flexible enough to provide virtually any transmision service its customers may decide to offer at

W. L. Pritchard; H. W. Radin

1984-01-01

23

A digital radio processor for channel demodulation and source decoding of satellite radio programs  

Microsoft Academic Search

New satellite based digital radio standards have been developed. The advantages of these standards (CD-like sound quality, small bandwidth requirements, embedded digital data services) require considerable larger modulation and demodulation efforts because forward error correction and sophisticated data compression techniques are used. The commercial success of these radio systems is closely related to the availability of low cost receiver equipment.

F.-O. Witte; R. Backes; M. Klumpp; W. Sinnhofer; S. Arendt

1996-01-01

24

Direct broadcast satellite-radio, space-segment/receiver tradeoffs  

NASA Technical Reports Server (NTRS)

The balance between receiver complexity and the required satellite equivalent isotropically radiated power (EIRP) for Direct Broadcast Satellite-Radio (DBS-R) service is addressed. In general the required receiver complexity and cost can be reduced at the expense of higher space-segment cost by allowing a higher satellite EIRP. The tradeoff outcome is sensitive to the total number of anticipated receivers in a given service area, the number of audio programs, and the required audio quality. An understanding of optimum choice of satellite EIRP for DBS-R under various service requirements is a critical issue at this time when International Radio Consultative Committee (CCIR) is soliciting input in preparation for the International Telecommunications Union (ITU) planning conference for the service.

Golshan, Nasser

1993-01-01

25

Microwave vacuum tubes for satellite radio  

Microsoft Academic Search

The present article discusses some of the general principles of microwave tubes and describes the traveling-wave tube (TWT) in detail. Beam-density-controlled tubes, transit-time tubes, drift tubes or klystrons, and the magnetron are also briefly explained. The mode of operation, special satellite requirements, service life, reliability, efficiency, and weight of the traveling-wave tube, as well as data on one TWT already

H. Rothfuss

1975-01-01

26

Digital audio for satellite network radio  

NASA Astrophysics Data System (ADS)

The paper presents the time-division-multiplexed (TDM) digital system supplied by Scientific-Atlanta for ABC, CBS, and NBC. The system has a transmission rate of 8.78 Mbps, and can demodulate, decode and demultiplex the data into the desired audio and data channels, supporting data rates equivalent to twenty 15 kHz audio channels at 384 kbps each. Digital transmission is used for data and channel use flexibility, and efficient usage of the satellite transponder. This TDM digital earth terminal configuration provides very high quality audio reception, built-in expansion capability for future services, and relative immunity to terrestrial interference.

McBride, A. L.

1982-04-01

27

Radio wave propagation measurements for land-mobile satellite systems at 2.33 GHz  

Microsoft Academic Search

The performance of a mobile satellite communications link is dominated by roadside attenuation due to vegetation or manmade structures. Previous measurement campaigns characterized land-mobile satellite channels at UHF and L bands. In 1997, the FCC allocated S-band spectrum to the Digital Audio Radio Satellite (DARS) service to provide nationwide radio services to the North American continent via satellite. This article

L. Mousselon; R. M. Barts; S. Licul; G. Joshi

2003-01-01

28

Protocol design for mobile radio group communications over satellite  

Microsoft Academic Search

The protocol design for a mobile radio service supporting half-duplex push-to-talk voice communications over mobile satellite systems is presented. Two types of protocols are considered, namely, a demand assignment multiple access protocol to assign channels only to those user groups in active sessions of conversations and a signaling protocol to arbitrate contentions among members of the same user group within

Victor C. M. Leung

1992-01-01

29

Satellite observations of transient radio impulses from thunderstorms  

SciTech Connect

Transient radio emissions from thunderstorms detected by satellites were first reported in 1995. The nature and source of these emissions remained a mystery until the launch of the FORTE satellite in 1997. FORTE, with its more sophisticated triggering and larger memory capacity showed that these emissions were connected to major thunderstorm systems. The analysis reported here, connecting FORTE RF events with ground based lightning location data from the National Lightning Detection Network (NLDN), shows that localized regions within thunderstorms are responsible for the creation of the satellite detected rf signals. These regions are connected with the areas of strong radar returns from the NEXRAD Doppler radar system, indicating that they are from regions of intense convection. The authors will also show data from several storms detected in the extended Caribbean, in which the height profile of the source regions can be determined. Although as a single low earth orbit satellite FORTE cannot provide global coverage of thunderstorm/lightning events, follow-on satellite constellations should be able to provide detailed information on global lightning in near real-time.

Argo, P.E.; Kirkland, M.; Jacobson, A.; Massey, R.; Suszynsky, D.; Eack, K.; Fitzgerald, T.J.; Smith, D.

1999-06-01

30

ATS6-satellite radio beacon measurements at Ootacamund, India  

NASA Technical Reports Server (NTRS)

In August 1975 the ATS6 was repositioned at 35 deg E. Radio beacon measurements of time delay, Faraday rotation and signal amplitude, made at Ootacamund, India in October 1975, are discussed with emphasis on the problem of determining the Faraday content under essentially transverse propagation conditions. It is shown that at the low geomagnetic latitude of Ootacamund the use of a fixed conversion coefficient gives an unreliable Faraday content. It is shown also that corrections to the measured Faraday rotation are important because of pitch and yaw of the satellite, particularly at night when the rotation on 140 MHz can be of the order of 10 to 20 deg. The shape factor shows a low predawn minimum indicating the nearly complete erosion of the F2 layer peak. Amplitude scintillation usually decreases with increase of radio frequency but exceptions are discussed.

Davies, K.; Donnelly, R. F.; Grubb, R. N.; Rama Rao, P. V. S.; Rastogi, R. G.; Deshpande, M. R.; Chandra, H.; Vats, H. O.; Sethia, G.

1978-01-01

31

Time transfer via satellite-link radio interferometry  

NASA Technical Reports Server (NTRS)

Very long baseline interferometry using natural radio sources was investigated as a possible time transfer method. Antennas were linked using a synchronous communications satellite instead of the customary independent frequency standards and tape recorders. A successful preliminary time transfer was performed using a wideband data link that was accurate at the 100 nanosecond level, and frequency standards were compared to a part in 10 to the minus thirteenth power over a 24 hour period using a phase coherent satellite link. The narrow band phase coherent link method is potentially capable of timing accuracy of 10 picoseconds, and frequency comparison accuracy of 10 to the minus sixteenth power, and is in addition economical of spectrum usage.

Knowles, S. H.; Waltman, W. B.; Yen, J. L.; Cannon, W. H.; Petrachenko, W. T.; Broten, N. W.; Costain, C.; Fort, D. H.; Galt, J. A.; Popelar, J.

1979-01-01

32

The RadioSat (sm) network  

Microsoft Academic Search

The RadioSat network under development by radio Satellite Corporation will use mobile satellite (MSAT) technology to provide diverse personal communications, broadcast, and navigation services. The network will support these services simultaneously for integrated mobile radios throughout Canada and the United States. The RadioSat network takes advantage of several technological breakthroughs, all coming to fruition by the time the first MSAT

Gary K. Noreen

1991-01-01

33

Utilizing a TDRS satellite for direct broadcast satellite-radio propagation experiments and demonstrations  

NASA Technical Reports Server (NTRS)

The NASA/VOA Direct Broadcast Satellite - Radio (DBS-R) Program will be using a NASA Tracking Data Relay Satellite (TDRS) satellite at 62 deg West longitude to conduct live satellite S-band propagation experiments and demonstrations of satellite sound broadcasting over the next two years (1993-1994). The NASA/VOA DBS-R program has applied intensive effort to garner domestic and international support for the DBS-R concept. An S-band DBS-R allocation was achieved for Region 2 at WARC-92 held in Spain. With this allocation, the DBS-R program now needs to conduct S-band propagation experiments and systems demonstrations that will assist in the development of planning approaches for the use of Broadcast Satellite Service (Sound) frequency bands prior to the planning conference called for by WARC-92. These activities will also support receiver concept development applied to qualities ranging from AM to Monophonic FM, Stereophonic FM, Monophonic CD, and Stereophonic CD quality.

Hollansworth, James E.

1993-01-01

34

Utilizing a TDRS satellite for direct broadcast satellite-radio propagation experiments and demonstrations  

NASA Technical Reports Server (NTRS)

The NASA/VOA Direct Broadcast Satellite-Radio (DBS-R) Program will be using a NASA Tracking Data Relay Satellite (TDRS) satellite at 62 deg. West longitude to conduct live satellite S-band propagation experiments and demonstrations of satellite sound broadcasting over the next two years (1993-1994). The NASA/VOA DBS-R program has applied intensive effort to garner domestic and international support for the DBS-R concept. An S-band DBS-R allocation was achieved for Region 2 at WARC-92 held in Spain. With this allocation, the DBS-R program now needs to conduct S-band propagation experiments and systems demonstrations that will assist in the development of planning approaches for the use of Broadcast Satellite Service (Sound) frequency bands prior to the planning conference called for by WARC-92. These activities will also support receiver concept development applied to qualities ranging from AM to Monophonic FM, Stereophonic FM, Monophonic CD, and Stereophonic CD quality.

Hollansworth, James E.

1993-01-01

35

Utilizing a TDRS satellite for direct broadcast satellite-radio propagation experiments and demonstrations  

NASA Technical Reports Server (NTRS)

The NASA/VOA Direct Broadcast Satellite - Radio (DBS-R) Program will be using a NASA Tracking Data Relay Satellite (TDRS) at 62 deg West longitude to conduct live satellite S-band propagation experiments and demonstrations of satellite sound broadcasting over the next two years (1993-1994). The NASA/VOA DBS-R program has applied intensive effort to garner domestic and international support for the DBS-R concept. An S-band DBS-R allocation was achieved for Region 2 at WARC-92 held in Spain. With this allocation, the DBS-R program now needs to conduct S-band propagation experiments and systems demonstrations that will assist in the development of planning approaches for the use of Broadcast Satellite Service (Sound) frequency bands prior to the planning conference called for by WARC-92. These activities will also support receiver concept development applied to qualities ranging from AM to Monophonic FM, Stereophonic FM, Monophonic CD, and Stereophonic CD quality.

Hollansworth, James E.

1993-01-01

36

Throughput analysis of CDMA access policies in radio determination satellite service  

Microsoft Academic Search

Policies for accessing a packet radio network, under the assumptions of the L-channel CDMA (code division multiple access) model and nonunity receiver idle probability, are proposed, and analytical tools to evaluate their performances are developed. These policies and tools are applicable to random access packet radio networks, such as the radio determination satellite service (RDSS) systems, which require wideband or

Lawrence C. Pond; V. O. K. Li

1989-01-01

37

Throughput analysis of CDMA access policies in radio determination satellite service  

Microsoft Academic Search

Policies for accessing a packet radio network, under the assumptions of the L-channel CDMA (code division multiple access) model and nonunity receiver idle probability, are proposed, and analytical tools to evaluate their performance are developed. These policies and tools are applicable to random access packet radio networks, such as the Radio Determination Satellite Service (RDSS) systems, which require wideband or

Lawrence C. Pond; Victor O. K. Li

1989-01-01

38

Satellite radio interface and radio resource management strategy for the delivery of multicast\\/broadcast services via an integrated satellite-terrestrial system  

Microsoft Academic Search

A variety of hybrid systems combining third-generation mobile communication networks with broadcast systems have been proposed for the delivery of multimedia broadcast multicast services (MBMS) to mobile users. The article discusses one of these alternatives, which involves the use of a geostationary satellite component for MBMS delivery. In particular, it proposes a radio access scheme for the satellite component of

M. Karaliopoulos; K. Narenthiran; B. Evans; P. Henrio; M. Mazzella; W. de Win; M. Dieudonne; P. Philippopoulos; D. I. Axiotis; I. Andrikopoulos; I. Mertzanis; G. E. Corazza; A. Vanelli-Coralli; N. Dimitriou; A. Polydoros

2004-01-01

39

76 FR 57923 - Establishment of Rules and Policies for the Satellite Digital Audio Radio Service in the 2310...  

Federal Register 2010, 2011, 2012, 2013

...FEDERAL COMMUNICATIONS COMMISSION 47 CFR Part 25...Policies for the Satellite Digital Audio Radio Service in the...Frequency Band AGENCY: Federal Communications Commission. ACTION: Final...contained in the Satellite Digital Audio Radio Service...

2011-09-19

40

Reminiscence: at the dawn of the space age [satellite radio transmissions  

Microsoft Academic Search

The author gives a personal account of some of the satellite radio communication experiments being carried out in the late 1950s and early 1960s. In particular the author mentions the Sputnik series of satellites and the Nora-Alice payloads on the Discoverer series of satellites. The study of the ionosphere is particularly discussed

1994-01-01

41

A satellite radio interface for IMT-Advanced system using OFDM  

Microsoft Academic Search

In this paper, we introduce a new satellite radio interface technology to provide efficient IMT-Advanced services. Maximizing the commonalities with the terrestrial system is one of the most important factors for cost-effective service delivery, which will finally bring successful deployment of the system. For this purpose, we adopt an OFDM based radio interface. At the same time, the interface should

Hee Wook Kim; Tae Chul Hong; Kunseok Kang; Bon Jun Ku; Sooyoung Kim; Sungmoon Yeo

2010-01-01

42

Direct broadcast satellite-radio: Portable and mobile reception trade-offs  

Microsoft Academic Search

There has been considerable international effort in the areas of system studies, system development, and regulatory work for a Direct Broadcast Satellite Radio (DBS-R). An important milestone will be the 1992 World Radio Administrative Conference (WARC 1992) consideration of frequency allocation in the 500 - 3000 MHz range for such a service. There is an interagency agreement between Voice of

Nasser Golshan

1991-01-01

43

Mobile radio alternative systems study satellite\\/terrestrial (hybrid) systems concepts  

Microsoft Academic Search

The use of satellites for mobile radio service in non-urban areas of the United States in the years from 1985 to 2000 was investigated. Several satellite concepts are considered: a system with single-beam coverage of the fifty United States and Puerto Rico, and multi-beam satellites with greater capacity. All of the needed functions and services identified in the market study

J. D. Kiesling; R. E. Anderson

1983-01-01

44

Study of mutual occultation phenomena of the Galilean satellites at radio wavelengths  

NASA Astrophysics Data System (ADS)

We present preliminary results for our study of mutual phenomena of the Galilean satellites performed at radio wavelengths with the Medicina and Noto antennas of the Istituto di Radioastronomia - INAF, and with the Effelsberg 100-m radio telescope of the Max-Planck-Institute for Radioastronomy, Bonn. Measurements of the radio flux density variation during the mutual occultations of Io by Europa and Ganymede were carried out during the PHEMU09 campaign at 22 GHz and 43 GHz. Flux density variations observed at radio wavelengths are consistent with the typical optical patterns measured when partial occultations occur.

Pluchino, S.; Salerno, E.; Pupillo, G.; Schillirò, F.; Kraus, A.; Mack, K.-H.

2010-01-01

45

Satellite-aided mobile radio concepts study: Concept definition of a satellite-aided mobile and personal radio communication system  

Microsoft Academic Search

The satellite system requires the use of a large satellite antenna and spacecraft array power of about 12 kW or more depending on the operating frequency. Technology developments needed include large offset reflector multibeam antennas, satellite electrical power sybsystems providing greater than 12 kW of power, signal switching hardware, and linearized efficient solid state amplifiers for the satellite-aided mobile band.

R. E. Anderson

1979-01-01

46

Public Radio and Television Audiences, Report 1; The Roper Surveys: A CPB (Corporation of Public Broadcasting) Special Report.  

ERIC Educational Resources Information Center

This report, one of two investigations into the use of public television and radio requested by the Corporation for Public Broadcasting and prepared by their Office of Communication Research, compares the demographic characteristics of the public-television viewer and the public-radio listener. Data gathered in the 1976 Roper Reports, which…

Corporation for Public Broadcasting, Washington, DC. Office of Communication Research.

47

Communications via the radio artificial earth satellite: Design of the tracking diagram and features for conducting QSO  

NASA Technical Reports Server (NTRS)

A detailed examination is made of the operation of a transmitting artifical Earth satellite. A tracking diagram for the satellite is constructed. The zone of radio visibility can be determined based on the techniques proposed.

Dobrozhanskiy, V.; Rybkin, V.

1980-01-01

48

CME-Associated Radio Bursts from Satellite Observations  

NASA Technical Reports Server (NTRS)

Coronal mass ejections (CMEs) are closely associated with various types of radio bursts from the Sun. All radio bursts are due to nonthermal electrons, which are accelerated during the eruption of CMEs. Radio bursts at frequencies below about 15 MHz are of particular interest because they are associated with energetic CMEs that contribute to severe space weather. The low-frequency bursts need to be observed primarily from space because of the ionospheric cutoff. The main CME-related radio bursts are associated are: type III bursts due to accelerated electrons propagating along open magnetic field lines, type II bursts due to electrons accelerated in shocks, and type IV bursts due to electrons trapped in post-eruption arcades behind CMEs. This paper presents a summary of results obtained during solar cycle 23 primarily using the white-light coronagraphic observations from the Solar Heliospheric Observatory (SOHO) and the WAVES experiment on board Wind. Particular emphasis will be placed on what we can learn about particle acceleration in the coronal and interplanetary medium by analyzing the CMEs and the associated radio bursts.

Gopalswamy, Nat

2012-01-01

49

Scientific instrumentation of the Radio-Astronomy-Explorer-2 satellite  

NASA Technical Reports Server (NTRS)

The instrumentation of the RAE-2 spacecraft is described. The instruments include a pair of long travelling-wave antennas, a 37-m dipole, two radiometers making one frequency scan every 144 sec, and two rapid-sampling total-power burst receivers which cover the range from 0.025 to 13.1 MHz in 32 discrete steps. Effects of terrestrial noise on RAE-1 and RAE-2 observations are discussed, and it is noted that RAE-2 is uniquely capable of observing repeated lunar occultations of strong radio sources at very low frequencies. Some observational programs are briefly noted, including observations of the galactic background distribution, measurements of lunar occultations of solar radio bursts, and searches for more radio sources among the planets, galactic objects, and extragalactic sources.

Alexander, J. K.; Kaiser, M. L.; Novaco, J. C.; Grena, F. R.; Weber, R. R.

1975-01-01

50

Analysis of satellite measurements of terrestrial radio noise  

NASA Technical Reports Server (NTRS)

Worldwide distributions of terrestrial radio noise as monitored by Radio Astronomy Explorer 1 (RAE 1) generated and compared with CCIR predictions. These contour maps show the global morphology of radio noise at 6.55 and 9.18 MHz for fall, winter, spring and summer during the local time blocks of 00-08 LT and 16-24 LT. These computer produced maps show general agreement with CCIR predictions over large land masses. The RAE and CCIR maps diverge at high latitudes over Asia and frequently over ocean regions. Higher noise levels observed by RAE at high latitudes are attributed to magnetospheric emission while higher noise levels observed by RAE over Asia are attributable to high power transmitters. Analysis of RAE noise observations in conjunction with various geophysical phenomena showed no obvious correlation.

Bakalyar, G.; Caruso, J. A.; Vargas-Vila, R.; Ziemba, E.

1974-01-01

51

An efficient demand-assignment multiple-access scheme for satellite mobile radio dispatch networks  

Microsoft Academic Search

Conventional DAMA (demand-assignment multiple access) designs process mobile radio calls in much the same way as mobile telephone calls. In mobile radio dispatch networks, where the dispatcher is often the resource bottleneck, these designs result in the inefficient use of satellite channels. A novel DAMA design is presented that ameliorates this problem by using the block-calls-queued service discipline, batched processing

V. C. M. Leung; M. O. Ali; A. I. Spolsky

1989-01-01

52

Interference experiments between fixed-satellite and terrestrial radio-relay services  

Microsoft Academic Search

To resolve interference problems between fixed-satellite and terrestrial radio relay services and expand coordination areas between the two services, theoretical and experimental studies were carried out. Theoretical D\\/U values calculation formulas between the two systems were derived, interference data from 4 GHz and 11 GHz band terrestrial radio-relay systems were obtained by a measuring system mounted on a vehicle. By

TAKESHI HATSUDA; Y. Motozumi

1998-01-01

53

An efficient demand-assignment multiple-access scheme for satellite mobile radio dispatch networks  

Microsoft Academic Search

Conventional demand-assignment multiple access (DAMA) designs process mobile radio calls in much the same way as mobile telephone calls. In mobile radio dispatch networks, where the dispatcher is often the resource bottleneck, these designs result in the inefficient use of satellite channels. A novel DAMA design is presented that ameliorates this problem by using the block-calls-queued service discipline, batched processing

Victor C. M. Leung; Mohammad O. Ali; Andrew I. Spolsky

1989-01-01

54

A FIVE-BAND ANTENNA FOR TERRESTRIAL AND SATELLITE RADIO SERVICES  

Microsoft Academic Search

A five band antenna for the terrestrial radio services GSM (900MHz) and UMTS (2000MHz) as well as for the satellite radio services Globalstar (1616MHz and 2.5GHz) and GPS (1575MHz) is developed, realized and tested. The radiation characteristic of the antenna is horizontally omni-directional for vertically polarized waves at the frequency bands of the terrestrial services GSM and UMTS and exhibits

S. Lindenmeier; G. R. Olbrich; J. F. Luy; P. Russer

55

ATS6-satellite radio beacon measurements at Ootacamund, India  

Microsoft Academic Search

In August 1975 the ATS6 was repositioned at 35 deg E. Radio beacon measurements of time delay, Faraday rotation and signal amplitude, made at Ootacamund, India in October 1975, are discussed with emphasis on the problem of determining the Faraday content under essentially transverse propagation conditions. It is shown that at the low geomagnetic latitude of Ootacamund the use of

K. Davies; R. F. Donnelly; R. N. Grubb; P. V. S. Rama Rao; R. G. Rastogi; M. R. Deshpande; H. Chandra; H. O. Vats; G. Sethia

1978-01-01

56

Low-Earth-orbit store-and-forward satellites in the amateur radio service  

Microsoft Academic Search

The authors review the current state of the art in amateur radio store-and forward satellite communications. Several operating satellite systems are described along with the procedures, equipment, and software required to access them. For PACSAT-1 empirical data have been used to estimate a downlink bit error probability of 6.0E-5. A further description of downlink performance is given through the examination

Robert J. Diersing; Greg Jones

1992-01-01

57

Engineering the satellite radio interface of a hybrid satellite-terrestrial system for MBMS delivery  

Microsoft Academic Search

The synergy between satellite and terrestrial mobile networks is regarded as a promising approach for the delivery of broadcast and multicast services to mobile users. This paper evolves around a hybrid satellite-terrestrial system, featuring a unidirectional satellite component that is responsible for the delivery of point-to-multipoint services. It proposes a systematic approach for the satellite system capacity partitioning between streaming

M. Karaliopoulos; K. Narenthiran; B. Evans; M. Neri; G. Albertazzi

2004-01-01

58

Terrestrial Myriametric Radio Burst Observed by IMAGE and Geotail Satellites  

NASA Technical Reports Server (NTRS)

We report IMAGE and Geotail simultaneous observations of a terrestrial myriametric radio burst (TMRB) detected on August 19, 2001. The TMRB was confined in time (0830-1006 UT) and frequency (12-50 kHz), suggesting a fan beam-like emission pattern from a single discrete source. Analysis and comparisons with existing TMR radiations strongly suggest that the TMRB is a distinct emission perhaps resulting from dayside magnetic reconnection instigated by northward interplanetary field condition.

Fung, Shing F.; Hashimoto, Kozo; Boardsen, Scott A.; Garcia, Leonard N.; Green, James L.; Matsumoto, Hiroshi; Reinisch, Bodo W.

2010-01-01

59

Eliminating adjacent-channel interference in satellite-based General Packet Radio Service (GPRS) systems  

Microsoft Academic Search

This paper presents a method for eliminating adjacent-channel interference (ACI) in satellite-based General Packet Radio Service (GPRS) systems using a new fuzzy adaptive filters (FAF). We validate the reasons for using such a filter by analyzing the Bayesian detector in which some parameter uncertainties exist. A clustering method is used to adaptively design the parameters of the FAF. Simulation results

Qilian Liang

2002-01-01

60

Investigation of a compact antenna diversity set for satellite radio applications  

Microsoft Academic Search

Antenna diversity sets are presented for mobile reception of satellite digital radio signals in the S-band. Different antenna types are combined to antenna diversity sets with an overall size comparable to a conventional single antenna. Measurements results of the reflection coefficient and the mutual coupling between the antennas are shown. An improved radiation pattern is achieved by phase shifting and

Dominikus J. Muller; Marcel Weikert; Stefan M. Lindenmeier

2010-01-01

61

Effects of the Earth's Ionosphere on HF Radio Astronomy from Artificial Satellites  

Microsoft Academic Search

A theoretical analysis of the effects of the ionosphere on HF observations from satellite-borne radio telescopes is presented. The primary effect investigated is the focusing effect of the ionosphere on incoming cosmic noise. This effect was computed according to the Hamiltonian equations for a ray path in a general magnetoionic medium, assuming the ionosphere to be a nonhomogenous, nonisotropic, magnetoionic

M. D. Grossi; K. M. Strom; S. E. Strom

1961-01-01

62

Radio sky mapping from satellites at very low frequencies  

NASA Technical Reports Server (NTRS)

Wave Distribution Function (WDF) analysis is a procedure for making sky maps of the sources of natural electromagnetic waves in space plasmas, given local measurements of some or all of the three magnetic and three electric field components. The work that still needs to be done on this subject includes solving basic methodological problems, translating the solution into efficient algorithms, and embodying the algorithms in computer software. One important scientific use of WDF analysis is to identify the mode of origin of plasmaspheric hiss. Some of the data from the Japanese satellite Akebono (EXOS D) are likely to be suitable for this purpose.

Storey, L. R. O.

1991-01-01

63

ATS-6 satellite radio beacon measurements at Ootacamund, India  

NASA Technical Reports Server (NTRS)

ATS-6 radio beacon measurements of modulation phase and Faraday rotation made at Ootacamund, India in 1975-1976 are discussed with emphasis on the measurement and analysis errors. The modulation-phase errors are insensitive to the geomagnetic field and provide an accurate determination of the total columnar electron content. Comparison of modulation-phase measurements at different frequencies shows a minor sensitivity to the ATS-6 pitch angle. For the low geomagnetic latitude and nearly transverse propagation conditions of Ootacamund, the use of a fixed conversion coefficient gives an unreliable Faraday content. However, the Faraday rotation measurements may be used to determine the shape factor F, which provides information about the electron density height profile.

Davies, K.; Donnelly, R. F.; Grubb, R. N.; Rao, P. V. S. R.; Rastogi, R. G.; Deshpande, M. R.; Chandra, H.; Vats, H. O.; Sethia, G.

1979-01-01

64

Using a Satellite Swarm for building a Space-based Radio Telescope for Low Frequencies  

NASA Astrophysics Data System (ADS)

In radio astronomy, as in astronomy in general, a wide range of frequencies is observed as each spectral band offers a unique window to study astrophysical phenomena. In the recent years, new observatories have been designed and built at the extreme limits of the radio spectrum. For the low frequencies several Earth-based radio telescopes are constructed at this moment. In the Netherlands, the Low Frequency Array (LOFAR) is being constructed at this moment and will be operational later this year. LOFAR observes the sky between 30 and 240 MHz. Observing at even lower frequencies is very interesting, but, due to the influence of the Earth's ionosphere this is not possible from Earth. Thus, the only option to observe low frequencies is a telescope in space. In the past several studies have been conducted on a low-frequency space-based radio tele-scope. In the recent ESA project Distributed Aperture Array for Radio Astronomy in Space (DARIS), such a mission was studied in detail. The study focused on a moderate-size three-dimensional satellite constellation operating as a coherent large-aperture synthesis array. The DARIS project is presented in a separate conference contribution. In the DARIS project the focus was on technology available at this moment, with an outlook and technological development plan/roadmap to be exploited for the future. Using current-day technologies, a space-based low-frequency array would be bulky and, thus, costly. A logical next step would be to investigate possibilities to miniaturize the electronics and use very small satellites, perhaps even nano satellites with masses between 1-10 kg to build the radio tele-scope. The approach is to use a swarm of satellites to establish a virtual telescope to perform the astronomical task. This is investigated in the NWO/STW-funded OLFAR (Orbiting Low Frequency Array) project. The OLFAR radio telescope will be composed of an antenna array based on satellites deployed at a location where the Earth's interference is limited, and where the satellites can be maintained in a three-dimensional configuration with a maximum diameter of 100 km. A Moon orbit could be suitable option. Each individual satellite will consist of deployable antennas. The sky signals will be amplified using an integrated ultra-low power direct sampling receiver and digitizer. Using digital fil-tering, any subband within the LNA passband can be selected. The data will be distributed over the available nodes in space. On-board signal processing will filter the data, invoke RFI mitigation algorithms (if necessary), and finally, correlate the data in a phased array mode. If more satellites are available, they will automatically join the array. The final correlated or beam-formed data will be sent to Earth as part of the telemetry data using a radio link. As the satellites will be far away from Earth, communication to and from Earth will require diversity communication schemes, using all the individual satellites together. In this paper, the design parameters for the satellites and the swarm will be discussed and status of the OLFAR project will be reported. Details will be given about the system and the signals that are expected.

Bentum, Mark; Boonstra, A. J.; Verhoeven, C. J. M.; van der Veen, A. J.; Gill, E. K. A.; Saks, N.; Falcke, H.; Klein-Wolt, M.; Rajan, R. T.; Wijnholds, S. J.; Arts, M.; van't Klooster, K.; Beliün, F.; Meijerink, A.; Monna, B.; Rotteveel, J.; Boer, M. A.; Bongers, E.; Boom, E.; van Tuijl, E.; van Staveren, A.

65

Femto-Satellite system for radio-occultation study of the Ionosphere  

NASA Astrophysics Data System (ADS)

This research project proposes the use of (a swarm of) Femto-Satellites in the study of Ionospheric properties using \\underline{Radio-Occultation} techniques. It makes use of GPS signals, a computing system, tiny on-board components and a data transfer module. This project is being done as a cheaper and lightweight alternative proposal to the higher cost, already running COSMIC program and other programs which use larger satellites to perform Radio-Occultation study of the Ionosphere. Being that these femto-satellites are capable of acting as a constellation, they will be able to provide higher accuracy radio-occultation readings of the Ionosphere due to the close proximity between each satellite positioned in low earth orbit. Important parameters attempted for this system include a weight of 100 grams per satellite system and an innovative power source using solar sails. The sails also serve to provide an anti-debris system of redundancy to make sure these tiny satellites don't add to the already alarming amount of space debris, in the event of a malfunction. Ultimately, having a large amount of tiny satellites serving to study the ionosphere at closer proximities and obtain more accurate results will give the scientific community a better understanding of the constant changes in the space environment at a given altitude. This could help humanity combat adverse changes in climate, which heavily affects some regions of agriculture. This could also help advance the scientific campaign against global warming, by providing real-time readings from different regions of the ionosphere.

Savio Bradford, Brandon; Gutierrez Cabello, Jordi

66

The Influence of The Galilean Satellites on Radio Emissions From The Jovian System  

NASA Technical Reports Server (NTRS)

The Galilean satellites influence radio emissions from the Jovian system in a variety of ways. The best and most familiar example of these is the Io control of decametric radiation discovered in 1964 by Bigg. Voyager observations of broadband kilometric radiation revealed a low-latitude shadow zone cast by the Io torus at frequencies between a few tens of kHz and about 1 MHz. Voyager also discovered narrowband kilometric radio emissions emanating from the outer edge of the torus. In this paper we will discuss expansions in the suite of satellite influences based on new observations by Galileo. These include the discovery of Ganymede's magnetosphere and evidence of radio emissions generated via mode conversion from upper hybrid waves in the frequency range of about 20 - 100 kHz. There is evidence that Ganymede may control some of the hectometric or low-frequency decametric radio emissions based on occultation measurements and statistical studies of radio emission occurrence as a function of Ganymede phase. Direction-finding measurements in the vicinity of Io suggest that a portion of the hectometric emissions may be generated near the lo L-shell. A rotationally modulated attenuation band in the hectometric emission appears to be the result of scattering at or near the Io L-shell where the waves propagate nearly parallel to the magnetic field. There is even a tantalizing hint of a Europa connection to the source of narrowband kilometric radiation.

Kurth, W. S.; Gurnett, D. A.; Menietti, J. D.

2000-01-01

67

Prospects for Lunar Satellite Detection of Radio Pulses from Ultrahigh Energy Neutrinos Interacting with the Moon  

E-print Network

The Moon provides a huge effective detector volume for ultrahigh energy cosmic neutrinos, which generate coherent radio pulses in the lunar surface layer due to the Askaryan effect. In light of presently considered lunar missions, we propose radio measurements from a Moon-orbiting satellite. First systematic Monte Carlo simulations demonstrate the detectability of Askaryan pulses from neutrinos with energies above 10^{20} eV, i.e. near and above the interesting GZK limit, at the very low fluxes predicted in different scenarios.

O. Stål; J. E. S. Bergman; B. Thidé; L. K. S. Daldorff; G. Ingelman

2006-04-10

68

Propagation measurements for satellite radio reception inside buildings  

NASA Technical Reports Server (NTRS)

Swept CW signals (from 700 to 1800 MHz) were received inside six buildings of brick, corrugated sheet-metal, wood-frame, mobile-home, and reinforced concrete-wall construction. A transmitter antenna was mounted outdoors on top of an 18 m tower to simulate a satellite, and a linearly scanned directional receiver antenna was used to probe the spatial, spectral, and temporal variability of the signal indoors. Levels were found to have much structure in the spatial and frequency domain, but were relatively stable in time. Typically, people moving nearby produced variations of less than 0.5 dB, whereas a person blocking the transmission path produced fades of 6 to 10 dB. Severe losses (17.5 dB) were observed in the concrete-wall building, which also exhibited the longest multipath delays (over 100 ns). Losses inside a mobile home were even larger (over 20 dB) and were independent of antenna orientation. The power-frequency distortion increased with the logarithm of the bandwidth, but could be reduced by moving to a position of higher power. Only the losses showed a clear frequency dependence, but they could be mitigated by moving the antenna.

Vogel, Wolfhard J.; Torrence, Geoffrey W.

1993-01-01

69

Broadcasting of radio programmes by satellite direct to portable/vehicle receivers  

NASA Astrophysics Data System (ADS)

The technical and economic feasibility of direct satellite broadcast of sound radio to portable receivers is evaluated, with a focus on coverage of rural areas in Africa. The need for improved coverage is indicated, and the cost of the terrestrial alternative (a network of solar-powered VHF/FM transmitters) is estimated as about one million dollars/year (spread over 10 yrs) for a country like kenya. The satellite system recommended uses the 0.5-2.0-GHz UHF band, a large satellite with a 10-m-diameter antenna and at least 100-W power (perhaps a multichannel satellite serving several countries or providing both direct-broadcast and trunk-communications functions), and portable or car receivers comprising a standard VHF/FM radio plus a UHF/VHF converter and a printed-Yagi or slot-dipole antenna. It is argued that the satellite system can be economically competitive with the terrestrial network and provide more reliable service. Allocation of orbital positions and frequencies for sond broadcasting is scheduled for consideration at the next WARC, ORB-85 in August 1985.

Chaplin, J.; Fromm, H.-H.; Rosetti, C.

1984-02-01

70

Broadcasting of radio programmes by satellite direct to portable\\/vehicle receivers  

Microsoft Academic Search

The technical and economic feasibility of direct satellite broadcast of sound radio to portable receivers is evaluated, with a focus on coverage of rural areas in Africa. The need for improved coverage is indicated, and the cost of the terrestrial alternative (a network of solar-powered VHF\\/FM transmitters) is estimated as about one million dollars\\/year (spread over 10 yrs) for a

J. Chaplin; H.-H. Fromm; C. Rosetti

1984-01-01

71

Near-Real Time Satellite Orbit Determination for GPS Radio Occultation with CHAMP and GRACE  

Microsoft Academic Search

\\u000a Precise and rapidly available orbits of GPS and Low-Earth-Orbiting (LEO) satellites are the prerequisite for processing of\\u000a the radio occultation data from CHAMP, GRACE and other LEOs performing occultation measurements. For efficient occultation\\u000a data assimilation by the weather prediction systems a 3 h timeline is required. In 2002 GFZ has started to generate orbits\\u000a at fixed 3 h intervals with a mean

Grzegorz Michalak; Rolf König

72

Analysis of type 3 solar radio bursts observed at kilometric wavelengths from the OGO-5 satellite  

NASA Technical Reports Server (NTRS)

Research was conducted to analyze the data on solar radio bursts obtained by the OGO-5 satellite. Since the wavelengths corresponding to the three lowest frequencies of observations exceeded one kilometer, the bursts detected in those channels were designated as kilometer-waves. The data search covered approximately 9200 hours between March 1968 and February 1970, and included the maximum of solar cycle No. 20. The study concentrated on 64 Type 3 solar radio events reaching frequencies equal or lower than 0.35 MHz. This selection criteria led to the choice of the most intense radio events. Measurements included: times of start, times of decay, and amplitudes of the 64 events. The consistency of the results, within the accuracy of the measurements, lends support to some of the assumptions made for the analysis, notably, the validity of the local plasma hypothesis, the constancy of the exciter particles velocity, and spiral shape of their trajectory.

Alvarez, H.

1971-01-01

73

Provision of the required navigation characteristics of satellite radio navigation systems in unfavorable helio-geophysical conditions  

Microsoft Academic Search

A detailed review of domestic and foreign scientific publications, dedicated to the influence of geomagnetic disturbances\\u000a and powerful bursts of the Sun’s radio radiation on the operation quality of satellite radio navigation systems (SRNS) and\\u000a their functional additions, is performed. It is shown that existing methods of providing the required radio navigation characteristics\\u000a during operation of the SRNS user’s device

V. V. Demyanov; E. L. Afraimovich; A. M. Alesshechkin

2009-01-01

74

Efficient use of the Earth exploration-satellite service radio frequency allocation in 8025-8400 MHz  

Microsoft Academic Search

The radio frequency spectrum (9 kHz-275 GHz) is a limited finite resource for which many radio services compete. Most of the 525 radio frequency bands are shared by two or more of the 30 recognized services. Worldwide, except for some individual country differences, in the 8025-8400 MHz range, often referred to as the X-band, the Earth exploration-satellite service (EESS) shares

David F. McGinnis Jr.; Wayne A. Whyte Jr.; Edward M. Davison

2005-01-01

75

A fast switching antenna diversity system for improved mobile reception of digital radio signals of a geostationary satellite  

Microsoft Academic Search

In severe multipath propagation scenarios - as for example underneath dense foliage or between buildings - the mobile reception of satellite digital audio radio services (SDARS) can be severely impaired. Antenna diversity is able to increase reception in such scenarios and to increase the link margin of satellite signal transmission. In this contribution a scan-phase antenna diversity system is shown

Simon Senega; Stefan M. Lindenmeier

2011-01-01

76

The Case Against Satellites. The Network Project. Notebook Number Seven.  

ERIC Educational Resources Information Center

An analysis is presented of the dangers generated by the corporate ownership of a satellite communications technology powerful enough to centralize and control the flow of information. The first part of the report reprints the transcript of a radio documentary on satellite communications, one of a series of five MATRIX radio programs produced by…

Columbia Univ., New York, NY. Network Project.

77

Adaptive sparse signal processing of satellite-based radio frequency (RF) recordings of lightning events  

NASA Astrophysics Data System (ADS)

Ongoing research at Los Alamos National Laboratory studies the Earth's radio frequency (RF) background utilizing satellite-based RF observations of terrestrial lightning. Such impulsive events are dispersed through the ionosphere and appear as broadband nonlinear chirps at a receiver on-orbit. They occur in the presence of additive noise and structured clutter, making their classification challenging. The Fast On-orbit Recording of Transient Events (FORTE) satellite provided a rich RF lightning database. Application of modern pattern recognition techniques to this database may further lightning research in the scientific community, and potentially improve on-orbit processing and event discrimination capabilities for future satellite payloads. Conventional feature extraction techniques using analytical dictionaries, such as a short-time Fourier basis or wavelets, are not comprehensively suitable for analyzing the broadband RF pulses under consideration here. We explore an alternative approach based on non-analytical dictionaries learned directly from data, and extend two dictionary learning algorithms, K-SVD and Hebbian, for use with satellite RF data. Both algorithms allow us to learn features without relying on analytical constraints or additional knowledge about the expected signal characteristics. We then use a pursuit search over the learned dictionaries to generate sparse classification features, and discuss their performance in terms of event classification. We also use principal component analysis to analyze and compare the respective learned dictionary spaces to the real data space.

Moody, Daniela I.; Smith, David A.

2014-05-01

78

Recovery of refractivity profiles and pressure and temperature distributions in the lower atmosphere from satellite-to-satellite radio occultation data  

NASA Technical Reports Server (NTRS)

The feasibility of recovering parameters from one-way range rate between two earth orbiting spacecraft during occultation of the tracking signal by the earth's lower atmosphere. The tracking data is inverted by an integral transformation (Abel transform) to obtain a vertical refractivity profile above the point of closest approach of the ray connecting the satellites. Pressure and temperature distributions can be obtained from values of dry refractivity using the hydrostatic equation and perfect gas law. Two methods are investigated for recovering pressure and temperature parameters. Results show that recovery is much more sensitive to satellite velocity errors than to satellite position errors. An error analysis is performed. An example is given demonstrating recovery of parameters from radio occultation data obtained during satellite-to-satellite tracking of Nimbus 6 by the ATS 6 satellite.

Murray, C. W., Jr.

1977-01-01

79

ATS-6 - Radio Beacon Experiment: The first years. [ionospheric and satellite-to-ground electron content  

NASA Technical Reports Server (NTRS)

The Radio Beacon Experiment aboard Applications Technology Satellite-6 (ATS-6) is designed to measure the total electron content and the ionospheric electron content between the satellite and ground. The spaceborne beacon transmits signals on frequencies of 40, 140, and 360 MHz with amplitude modulations of 1 MHz and/or 0.1 MHz for the measurement of modulation phase, Faraday rotation, and amplitude. The modulation phase delays are calibrated in the satellite and in the ground equipment, and the polarization of the emitted signals are predetermined by standard antenna range techniques. The design of the ATS-6 receiver in Boulder, Colorado, is discussed. The antennae are of the short backfire type described by Ehrenspeck (1967), with nominal gains of 13, 19, and 22 dB at 40, 140, and 360 MHz, respectively. Data recording and overall supervision of the receiver is carried out by a 16-bit minicomputer with 8 k of memory. Overall performance of the system is satisfactory. Sample data on the monthly median hourly values of the total electron content, plasmospheric content, and shape factor show distinct seasonal and diurnal variations.

Davies, K.; Fritz, R. B.; Grubb, R. N.; Jones, J. E.

1975-01-01

80

Airborne Remote Observations of L-Band Radio Frequency Interference and Implications for Satellite Missions  

NASA Technical Reports Server (NTRS)

Passive remote sensing of the Earth s surface and atmosphere from space has significant importance in operational and research environmental studies, in particular for the scientific understanding, monitoring and prediction of climate change and its impacts. Passive remote sensing requires the measurement of naturally occurring radiations, usually of very low power levels, which contain essential information on the physical process under investigation. As such, these sensed radio frequency bands are a unique natural resource enabling space borne passive sensing of the atmosphere and the Earth s surface that deserves adequate allocation to the Earth Exploration Satellite Service and absolute protection from interference. Unfortunately, radio frequency interference (RFI) is an increasing problem for Earth remote sensing, particularly for passive observations of natural emissions. Because these natural signals tend to be very weak, even low levels of interference received by a passive sensor may degrade the fidelity of scientific data. The characteristics of RFI (low-level interference and radar-pulse noise) are not well known because there has been no systematic surveillance, spectrum inventory or mapping of RFI. While conducting a flight experiment over central Tennessee in May 2010, RFI, a concern for any instrument operating in the passive L band frequency, was observed across 16 subbands between 1402-1427 MHz. Such a survey provides rare characterization data from which to further develop mitigation technologies as well as to identify bandwidths to avoid in future sensor formulation.

Laymon, Charles; Srinivasan, Karthik; Limaye, Ashutosh

2011-01-01

81

Maritime terrestrial and satellite communications - Their relative role in the overall maritime radio-communication service in the coming decades  

Microsoft Academic Search

The considerations set forth in the present paper indicate that the maritime radio communications service of the future will be arrived at only after extensive international discussion in a number of fora, including IMCO and CCIR. With the arrival of satellite communications, this process of consultation is at a watershed. It is time now for ideas to be discussed. Gradually

S. R. Temple

1978-01-01

82

Monitoring the Atmospheric Boundary Layer by Radio Occultation Signals Recorded by COSMIC Satellites  

NASA Astrophysics Data System (ADS)

The Constellation Observing System for Meteorology, Ionosphere and Climate (COSMIC) uses radio occultation (RO) observations of the Global Positioning System (GPS) satellites to retrieve vertical profiles of the bending angle and refractivity in the atmosphere. Unlike previous RO missions utilizing the phase-locked loop (PLL) signal tracking technique, COSMIC receivers record L1 GPS signals in open-loop (OL) mode in the lowest 10 km of the troposphere by allowing penetration of the retrieved profiles down to the ocean surface. This provides an opportunity for monitoring the atmospheric boundary layer (ABL) with high vertical resolution (50-100 m), not available from other satellite data and not generally possible with PLL RO data from previous RO missions due to insufficient penetration and tracking errors. The optimal way of utilizing information about the ABL from RO observations is direct assimilation of the inverted bending angle and refractivity profiles into atmospheric models with sufficiently high vertical resolution in the lower troposphere. Alternatively, estimates of the depth of the ABL, which is an important parameter for meteorology and climatology, can be extracted from the structure of RO signals and inverted profiles. Such methods and results of their application to COSMIC RO data will be discussed.

Sokolovskiy, S.; Kuo, Y.; Rocken, C.; Schreiner, W.; Hunt, D.; Anthes, R.; Lenschow, D.

2006-12-01

83

Protection of passive radio frequencies used for earth exploration by satellite  

NASA Astrophysics Data System (ADS)

Space-borne passive sensing of the Earth"s surface and atmosphere has an essential and increasing importance in Earth Observation. The impressive progress recently made or shortly expected in weather analysis, warning and forecasts (in particular for dangerous weather phenomena as rain and floods, storms, cyclones, droughts) as well as in the study and prediction of climate change, is mainly attributable to the spaceborne observations. On this basis, economic studies show that meteorological services have a high positive impact on a wide range of economic activities, notwithstanding safety of life and property aspects. Space-borne passive sensing feeds crucial observational data to numerical weather predction models run on the most advanced super-computers that are operated by a few global forecasting centers. All meteorological and environmental satellite organizations operate these crucial remote-sensing missions as part of the GOS of the World Weather Watch and others... Spaceborne passive sensing for meterological applications is performed in frequency bands allocated to the Earth Exploration-Satellite Service. This is named "EESS passive" in the ITU-R Radio Regulations. The appropriate bands are uniquely determined by the physical properties (e.g. molecular resonance) of constituents of the atmosphere, and are therefore one of the unique natural resources (similarly to Radio Astronomy bands). Passive measurements at several frequencies in the microwave spectrum must be made simultaneously in order to extract the individual contribution of the geophysical parameter of interest. Bands below 100 GHz are of particular importance to provide an "all-weather" capability since many clouds are almost transparent at these frequencies. Along this line, the two first figures below about zenithal opacity describes respectively the atmosphere optical thickness due to water vapor and dry components in the frequency range 1 to 275 GHz and 275 GHz to 1000 GHz on which have been based the definition of most of the current allocations to EESS (passive) that are listed, as currently specified in ITU-R Rec. SA.515-3 summarized below. Interference criteria and performance criteria of passive sensors are indicated in ITU-R Rec(s) SA.1028-2 and 1029-2, respectively. A common summary of these two Rec(s) is also available below.

Rochard, Guy

2004-10-01

84

Efficient use of the Earth exploration-satellite service radio frequency allocation in 8025-8400 MHz  

NASA Astrophysics Data System (ADS)

The radio frequency spectrum (9 kHz-275 GHz) is a limited finite resource for which many radio services compete. Most of the 525 radio frequency bands are shared by two or more of the 30 recognized services. Worldwide, except for some individual country differences, in the 8025-8400 MHz range, often referred to as the X-band, the Earth exploration-satellite service (EESS) shares its space-to-Earth allocation with the fixed-satellite service (Earth-to-space) and the terrestrial fixed and mobile services. Additionally, the adjacent band, 8400-8450 MHz, is allocated to the space research service (deep space) in the space-to-Earth direction and radio frequency emissions from spaceborne or airborne stations can be particularly serious sources of interference to these space research operations. Managing the use of this spectrum requires consideration of not only the sharing among the allocated services but also within a given service. In particular, the continued growth in use of the EESS allocation by Earth-exploration satellites is nearing the capacity of the 375 MHz. In order to permit the maximum utilization, it is incumbent upon satellite network operators to consider innovative design techniques that result in spectral efficiency without causing harmful interference to other systems using the allocation. International and U.S. spectrum regulators, as well as the entities that manage Earth resource satellites using this band, have established guidelines that support such spectrum efficiency. This paper provides the three Federal agencies' thoughts on the current policy and the steps being taken to ensure the continued availability of this spectrum into the future.

McGinnis, David F., Jr.; Whyte, Wayne A., Jr.; Davison, Edward M.

2005-08-01

85

Direct broadcast satellite-radio market, legal, regulatory, and business considerations  

NASA Technical Reports Server (NTRS)

A Direct Broadcast Satellite-Radio (DBS-R) System offers the prospect of delivering high quality audio broadcasts to large audiences at costs lower than or comparable to those incurred using the current means of broadcasting. The maturation of mobile communications technologies, and advances in microelectronics and digital signal processing now make it possible to bring this technology to the marketplace. Heightened consumer interest in improved audio quality coupled with the technological and economic feasibility of meeting this demand via DBS-R make it opportune to start planning for implementation of DBS-R Systems. NASA-Lewis and the Voice of America as part of their on-going efforts to improve the quality of international audio broadcasts, have undertaken a number of tasks to more clearly define the technical, marketing, organizational, legal, and regulatory issues underlying implementation of DBS-R Systems. The results and an assessment is presented of the business considerations underlying the construction, launch, and operation of DBS-R Systems.

Sood, Des R.

1991-01-01

86

Direct broadcast satellite-radio market, legal, regulatory, and business considerations  

NASA Astrophysics Data System (ADS)

A Direct Broadcast Satellite-Radio (DBS-R) System offers the prospect of delivering high quality audio broadcasts to large audiences at costs lower than or comparable to those incurred using the current means of broadcasting. The maturation of mobile communications technologies, and advances in microelectronics and digital signal processing now make it possible to bring this technology to the marketplace. Heightened consumer interest in improved audio quality coupled with the technological and economic feasibility of meeting this demand via DBS-R make it opportune to start planning for implementation of DBS-R Systems. NASA-Lewis and the Voice of America as part of their on-going efforts to improve the quality of international audio broadcasts, have undertaken a number of tasks to more clearly define the technical, marketing, organizational, legal, and regulatory issues underlying implementation of DBS-R Systems. The results and an assessment is presented of the business considerations underlying the construction, launch, and operation of DBS-R Systems.

Sood, Des R.

1991-03-01

87

Capacity of a multi-beam, multi-satellite CDMA mobile radio networks with interference-mitigating receivers  

Microsoft Academic Search

Interference-resilient receivers for CDMA transmissions promise a noticeable capacity increase on theoretical grounds. Do they really bring forth such performance boost in a realistic scenario? The aim of this study is to give a preliminary answer to such a question, through the capacity analysis of the forward link of a multi-satellite, multi-beam, radio communication network at S-band. Specifically, starting from

R. De Gaudenzi; F. Giannetti; M. Luise

1997-01-01

88

Predictions of HF system performance for propagation through disturbed ionospheres measured using low-Earth-orbit satellite radio beacon tomography  

NASA Astrophysics Data System (ADS)

CERTO radio beacon on the C/NOFS satellite sends VHF/UHF radio signals at 150 and 400 MHz to provide measurements of integrated electron density or Total Electron Content (TEC) by an east-west chain of ground receivers in Peru. Computerized Ionospheric Tomography (CIT) is used to convert the TEC data into two-dimensional images of electron densities with maximum 5 × 5 km resolution in Longitude-Altitude space. These images are updated every 95 min as the C/NOFS satellite passes over the receiver network in its low-latitude orbit with an inclination of 12°. The 2-D, high-resolution images of the ionosphere are used to predict the impact of equatorial plasma structures on HF propagation of radar and radio signals. Electron density measurements from the NRL radio tomography chain across Peru are used for simulations of the performance by HF one-way links. HF rays from transmitter to receiver are traced through the electron density images produced by radio beacon tomography. Eight separate paths are found between a transmitter and ground receiver separated by 2000 km. A total of 36 backscatter echoes are found with unique group delay, Doppler frequency shift, phase delay, and echo amplitude. This multipath effect explains the range and Doppler spreading of observations for HF monostatic radar propagation through F layer irregularities. This type of analysis is useful for prediction and interpretation of range and Doppler observations from HF systems including over-the-horizon and SuperDARN radars, HF Geolocation Arrays, and HF communications networks.

Bernhardt, Paul A.; Hei, Matthew A.; Siefring, Carl L.; Wilkens, Matthew R.

2014-07-01

89

Radio resource management across multiple protocol layers in satellite networks: a tutorial overview  

Microsoft Academic Search

SUMMARY Satellite transmissions have an important role in telephone communications, television broadcasting, computer communications, maritime navigation, and military command and control. Moreover, in many situations they may be the only possible communication set-up. Trends in telecommunications indicate that four major growth market\\/service areas are messaging and navigation services (wireless and satellite), mobility services (wireless and satellite), video delivery services (cable

Paolo Barsocchi; Nedo Celandroni; Franco Davoli; Erina Ferro; Giovanni Giambene; Francisco Javier González Castaño; Alberto Gotta; Jose Ignacio Moreno; Petia Todorova

2005-01-01

90

Estimating water vapour along the radio path between two LEO satellites through multifrequency differential power measurements  

NASA Astrophysics Data System (ADS)

The Normalized Differential Spectral Attenuation (NDSA) concept was proposed in 2002 by the authors for tropospheric water vapour sounding by means of a couple of LEO (Low Earth Orbit) satellites (one carrying a transmitter, the other a receiver and operating in the Ku/K bands) in limb geometry. In those years, in the course of the ACE+ mission studies (second call for proposal of the ESA Earth Explorer Opportunity Mission), the problem arose of the severe impact of scintillation due to tropospheric turbulence on the water vapour estimates provided by radio occultation measurements made in limb mode between two LEO satellites. In following ESA studies (AlmetLeo - 2004, ACTLIMB -2009) it was demonstrated that NDSA, thanks to its normalised differential approach, is effective for limiting scintillation and for estimating the Integrated Water Vapor (IWV) along the propagation path between the two LEO satellites. NDSA relies on the conversion of a spectral parameter (the spectral sensitivity S), into the IWV through IWV-S relationships. S is a finite-difference approximation of the derivative of the spectral attenuation at a given frequency fo, normalized to the spectral attenuation itself. To measure Sat fo,it is required that two tone signals with equal power at relatively close frequencies f1 and f2 (f1 > f2) symmetrically placed around fo are simultaneously transmitted. The two pertinent received powers P1 and P2 are simultaneously measured and S is provided by: S = -P2--P1- (f1 - f2 )P2 From the very beginning of the NDSA studies, it was evident that in ideal measurement conditions (no disturbance at the receiver nor propagation impairments) S is tightly correlated to the IWV. To verify this, we accounted for natural variations of the atmospheric conditions by generating simulated spherically symmetric atmospheres using real radiosonde profiles. We computed IWV along the radio path and simulated S separately obtaining IWV-S relationships at various altitudes through regression methods. In particular, the ESA-AlMetLEO study yielded a significant insight into such relationships up to 12 km using the K-Ku bands, while the ESA-ACTLIMB study offered the opportunity to investigate the potential of 179 to 182 GHz (M band) for estimates from 10 km upwards, exhibiting a significant robustness to scintillation fluctuations. However, two problems affected the reliability of the empirical IWV-S relations found and have been faced by us during the on-going ESA-ANISAP study: 1) the accuracy of the radiosonde data used to derive them was not uniform in the northern and southern hemisphere, and so their positions; 2) the number of radiosonde samples above 10 km was limited, and their reliability scarce, which affected the analysis of the IWV-S relations in the M band. To overcome both problems, instead of radiosonde data, we utilized atmospheric pro?les equally distributed on a global Earth scale as derived from ECMWF atmospheric analysis data. Such database includes pressure, temperature, humidity, liquid water, ice water and wind components in 8 global datasets in 4 days amid of each of the four seasons and at two time layers (12:00 UTC and 24:00 UTC). In this work, we show the main results of the global scale analysis of the IWV-S relations up to 20 altitude. We point out that NDSA requires a multi-frequency approach to provide reliable IWV estimates up to 20 km, and that S estimates at 17, 19 and 21 GHz are essential to provide IWV profiles in the lower troposphere through linear relationships, while the M band channels (179 and 182 GHz) can be reliably exploited still through linear relationships above 10 km where the water vapour content is smaller. We also demonstrate that an additional spectral sensitivity channel at 32 GHz is very effective both to detect the presence of liquid water along the link and to correct the IWV overestimates caused by such presence when using S measurements in the K/Ku band (17, 19 and 21 GHz).

Facheris, Luca; Cuccoli, Fabrizio

2013-04-01

91

Low Earth-orbit store-and-forward satellites in the amateur radio service  

Microsoft Academic Search

Several aspects of the most recently launched low-earth-orbit (LEO) store-and-forward satellites operating in the amateur satellite service are described. Included are a description of the satellites and their most interesting implementation details, with particular emphasis on the communications system; a description of the file server and broadcast protocol; a description of operation from the user's viewpoint; and some statistics characterizing

Robert J. Diersing; Greg Jones

1993-01-01

92

The RadioSat (sm) network  

NASA Technical Reports Server (NTRS)

The RadioSat network under development by radio Satellite Corporation will use mobile satellite (MSAT) technology to provide diverse personal communications, broadcast, and navigation services. The network will support these services simultaneously for integrated mobile radios throughout Canada and the United States. The RadioSat network takes advantage of several technological breakthroughs, all coming to fruition by the time the first MSAT satellite is launched in 1994. The most important of these breakthroughs is the enormous radiated power of each MSAT spacecraft - orders of magnitude greater than the radiated power of previous L-band spacecraft. Another important breakthrough is the development of advanced digital audio compression algorithms, enabling the transmission of broadcast quality music at moderate data rates. Finally, continuing dramatic increases in VLSI capabilities permit the production of complex, multi-function mobile satellite radios in very large quantities at prices little more than those of conventional car radios. In addition to performance breakthroughs and their economic implications to RadioSat, the design of the RadioSat network is reviewed.

Noreen, Gary K.

1991-01-01

93

The RadioSat (sm) network  

NASA Astrophysics Data System (ADS)

The RadioSat network under development by radio Satellite Corporation will use mobile satellite (MSAT) technology to provide diverse personal communications, broadcast, and navigation services. The network will support these services simultaneously for integrated mobile radios throughout Canada and the United States. The RadioSat network takes advantage of several technological breakthroughs, all coming to fruition by the time the first MSAT satellite is launched in 1994. The most important of these breakthroughs is the enormous radiated power of each MSAT spacecraft - orders of magnitude greater than the radiated power of previous L-band spacecraft. Another important breakthrough is the development of advanced digital audio compression algorithms, enabling the transmission of broadcast quality music at moderate data rates. Finally, continuing dramatic increases in VLSI capabilities permit the production of complex, multi-function mobile satellite radios in very large quantities at prices little more than those of conventional car radios. In addition to performance breakthroughs and their economic implications to RadioSat, the design of the RadioSat network is reviewed.

Noreen, Gary K.

1991-09-01

94

Timing Synchronization in MF-TDMA Systems for Geostationary Satellites[Topics in Radio Communications  

Microsoft Academic Search

The most expensive costs in satellite communication are incurred by the space segment. Therefore, effort should be focused on the efficient use of this resource. One aspect is the optimization of the physical layer, to approach the Shannon limit of channel capacity. In IP-based networks, communication between arbitrary terminals can be established, which must hold for IP-based satellite networks as

Wolfgang Kogler; Harald Schlemmer; Otto Koudelka

2007-01-01

95

Small Satellite Applications of Commercial off the Shelf Radio Frequency Integrated Circuits  

E-print Network

-spacecraft platforms to expand civil and military mission possibilities. Small spacecraft have also given small organizations such as universities an increased access to space. Because small satellites are limited in size, power, and mass, new and often nontraditional...

Graves, John

2012-02-14

96

Results of 17 Independent Geopositional Accuracy Assessments of Earth Satellite Corporation's GeoCover Landsat Thematic Mapper Imagery. Geopositional Accuracy Validation of Orthorectified Landsat TM Imagery: Northeast Asia  

NASA Technical Reports Server (NTRS)

This report provides results of an independent assessment of the geopositional accuracy of the Earth Satellite (EarthSat) Corporation's GeoCover, Orthorectified Landsat Thematic Mapper (TM) imagery over Northeast Asia. This imagery was purchased through NASA's Earth Science Enterprise (ESE) Scientific Data Purchase (SDP) program.

Smith, Charles M.

2003-01-01

97

Demand assignment system design for a mobile satellite (MSAT) SCPC mobile radio service  

Microsoft Academic Search

The MSAT system is planned to provide mobile communication services to users needing wide area Canadian coverage and it is essential that efficient use be made of the limited spectrum by allocating SCPC channels on a demand assigned multiple access basis. This paper deals primarily with the design and specification of the mobile radio service DAMA system, with particular emphasis

G. R. McMillen; B. A. Mazur; J. D. B. Kent

1985-01-01

98

Low-profile cavity-backed crossed-slot antenna with a single-probe feed designed for 2.34GHz satellite radio applications  

Microsoft Academic Search

This paper describes a novel, low-profile antenna for the satellite digital audio radio service. The antenna consists of a thin cavity with a pair of crossed slots having unequal length. Both slots are fed by a single-probe-type feed, resulting in a simple low-cost structure. This antenna is left-hand circularly polarized toward the sky for satellite reception, and vertically polarizated toward

Dan Sievenpiper; Hui-Pin Hsu; Robert M. Riley

2004-01-01

99

Calculation of optimum transmitter-beam parameters for satellite radio broadcasting in the 12 GHz band  

Microsoft Academic Search

The paper suggests a procedure for calculating the optimum transmitting-beam and service zone parameters for the planned satellite which will broadcast in the 12 GHz band. The computation procedure is explained with attention to the main computing expressions, parameter-optimization principles, and computer program structure. A block diagram is provided, and, as an example, some results from the operation of the

L. M. Mashbits

1976-01-01

100

Wave propagation channel simulation by satellite-to-indoor radio link  

Microsoft Academic Search

In our paper we present the simulation of the propagation characteristics of the satellite-to-indoor propagation channel. Our first aim has been to find a correct description of the polarization state of the received inside wave. The result of our first in- vestigations is that the polarization state of the indoor wave signigicantly changes as we move further away from the

LÓRÁNT FARKAS; LAJOS NAGY; ANDREA FARKASVÖLGYI

2008-01-01

101

GIANT LOBES OF CENTAURUS A RADIO GALAXY OBSERVED WITH THE SUZAKU X-RAY SATELLITE  

SciTech Connect

We report on Suzaku observations of selected regions within the southern giant lobe of the radio galaxy Centaurus A. In our analysis we focus on distinct X-ray features detected with the X-ray Imaging Spectrometer within the range 0.5-10 keV, some of which are likely associated with fine structure of the lobe revealed by recent high-quality radio intensity and polarization maps. With the available photon statistics, we find that the spectral properties of the detected X-ray features are equally consistent with thermal emission from hot gas with temperatures kT > 1 keV, or with a power-law radiation continuum characterized by photon indices {Gamma} {approx} 2.0 {+-} 0.5. However, the plasma parameters implied by these different models favor a synchrotron origin for the analyzed X-ray spots, indicating that a very efficient acceleration of electrons up to {approx}> 10 TeV energies is taking place within the giant structure of Centaurus A, albeit only in isolated and compact regions associated with extended and highly polarized radio filaments. We also present a detailed analysis of the diffuse X-ray emission filling the whole field of view of the instrument, resulting in a tentative detection of a soft excess component best fitted by a thermal model with a temperature of kT {approx} 0.5 keV. The exact origin of the observed excess remains uncertain, although energetic considerations point to thermal gas filling the bulk of the volume of the lobe and mixed with the non-thermal plasma, rather than to the alternative scenario involving a condensation of the hot intergalactic medium around the edges of the expanding radio structure. If correct, this would be the first detection of the thermal content of the extended lobes of a radio galaxy in X-rays. The corresponding number density of the thermal gas in such a case is n{sub g} {approx} 10{sup -4} cm{sup -3}, while its pressure appears to be in almost exact equipartition with the volume-averaged non-thermal pressure provided by the radio-emitting electrons and the lobes' magnetic field. A prominent large-scale fluctuation of the Galactic foreground emission, resulting in excess foreground X-ray emission aligned with the lobe, cannot be ruled out. Although tentative, our findings potentially imply that the structure of the extended lobes in active galaxies is likely to be highly inhomogeneous and non-uniform, with magnetic reconnection and turbulent acceleration processes continuously converting magnetic energy to internal energy of the plasma particles, leading to possibly significant spatial and temporal variations in the plasma {beta} parameter around the volume-averaged equilibrium condition {beta} {approx} 1.

Stawarz, L.; Gandhi, P.; Takahashi, T.; Takei, Y. [Institute of Space and Astronautical Science JAXA, 3-1-1 Yoshinodai, Chuo-ku, Sagamihara, Kanagawa 252-5210 (Japan)] [Institute of Space and Astronautical Science JAXA, 3-1-1 Yoshinodai, Chuo-ku, Sagamihara, Kanagawa 252-5210 (Japan); Tanaka, Y. T.; Fukazawa, Y. [Department of Physical Sciences, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8526 (Japan)] [Department of Physical Sciences, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8526 (Japan); Madejski, G. [W. W. Hansen Experimental Physics Laboratory, Kavli Institute for Particle Astrophysics and Cosmology, Department of Physics and SLAC National Accelerator Laboratory, Stanford University, Stanford, CA 94305 (United States)] [W. W. Hansen Experimental Physics Laboratory, Kavli Institute for Particle Astrophysics and Cosmology, Department of Physics and SLAC National Accelerator Laboratory, Stanford University, Stanford, CA 94305 (United States); O'Sullivan, S. P. [Sydney Institute for Astronomy, School of Physics A28, University of Sydney, Sydney, NSW 2006 (Australia)] [Sydney Institute for Astronomy, School of Physics A28, University of Sydney, Sydney, NSW 2006 (Australia); Cheung, C. C. [National Academy of Sciences, Washington, DC 20001 (United States)] [National Academy of Sciences, Washington, DC 20001 (United States); Feain, I. J. [CSIRO Astronomy and Space Science, ATNF, P.O. Box 76, Epping, NSW 1710 (Australia)] [CSIRO Astronomy and Space Science, ATNF, P.O. Box 76, Epping, NSW 1710 (Australia); Hardcastle, M. J. [School of Physics, Astronomy and Mathematics, University of Hertfordshire, College Lane, Hatfield AL10 9AB (United Kingdom)] [School of Physics, Astronomy and Mathematics, University of Hertfordshire, College Lane, Hatfield AL10 9AB (United Kingdom); Kataoka, J.; Takeuchi, Y. [Research Institute for Science and Engineering, Waseda University, 3-4-1, Okubo, Shinjuku, Tokyo 169-8555 (Japan)] [Research Institute for Science and Engineering, Waseda University, 3-4-1, Okubo, Shinjuku, Tokyo 169-8555 (Japan); Ostrowski, M. [Astronomical Observatory, Jagiellonian University, ul. Orla 171, 30-244 Krakow (Poland)] [Astronomical Observatory, Jagiellonian University, ul. Orla 171, 30-244 Krakow (Poland); Reville, B. [Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU (United Kingdom)] [Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU (United Kingdom); Siemiginowska, A. [Harvard Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)] [Harvard Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Simionescu, A.; Werner, N., E-mail: stawarz@astro.isas.jaxa.jp [KIPAC, Stanford University, 452 Lomita Mall, Stanford, CA 94305 (United States)

2013-03-20

102

Guided radio-wave propagation in the equatorial ionosphere according to the Intercosmos-19 and Alouette/ISIS satellites  

NASA Astrophysics Data System (ADS)

In addition to normal vertical-incident ionogram traces, strongly remote (up to 2000 km), traces of HF-radio-signal reflections observed on topside-sounder ionograms of the Interkosmos-19 satellite obtained in the equatorial ionosphere are presented. Such traces are connected with waveguides (ducts). These waveguides are field-aligned irregularities of ionospheric plasma with electron density depletion of a few percent and cross-field dimension of a few to several kilometers. Ray tracing confirms this supposition and allows an estimate of the typical parameters of the waveguides. The waveguide traces usually start at the cutoff frequency of the main trace. However, sometimes they begin at much lower frequencies which indicate the waveguides are located in plasma bubbles. Only one ducted trace is usually observed on the Interkosmos-19 ionograms; a second conjugate trace is rarely recorded. Waveguides are observed at all heights of Interkosmos-19 (500-1000 km) inside the equatorial anomaly region (from -40 to +40 degrees DipLat). Ducted-echo characteristics observed with the Interkosmos-19 are different from those observed earlier with the Alouette and ISIS satellites. This difference is discussed. It is shown that the ionospheric plasma irregularities responsible for the waveguides are observed much more often during nighttime than during daytime.

Karpachev, Alexander; Zhbankov, Gennadii; Telegin, Viktor; Kuleshova, Valentina

103

Results from the northern New Mexico satellite-beacon radio interferometer  

SciTech Connect

An interferometer described in the Boston, 1992, meeting of the Beacon Satellite Symposium has been in full operation for over a year now. It consists of four autonomous stations; three are in a triangle 70 km on a side and one is in the center. The stations receive the VHF beacons from two geosynchronous satellites, GOES-2 and ATS-3. The phases of the beacons are tracked at each station by referring them to an extremely stable rubidium oscillator. The studies of the two satellites are virtually separate experiments. The received phase of the beacon is retarded by the increased Total-Electron-Content of the dense regions of waves in the ionosphere. By comparing the phase history at four spatially separated stations, the authors can determine the two-dimensional propagation vector of the waves. This array is optimal for wavelengths of 70--300 km (periods of 300--3,000 seconds). Since the measurement is of the phase of the signal rather than the difference between the O-mode and X-mode phases, and since the beacons are in the VHF rather than in the L-band of GPS beacons, the array is very sensitive. It has a noise level of 10{sup 13} electrons/m{sup 2}, or 10{sup {minus}4} of the normal daytime TEC. This has been verified by operating two stations in the same location, so that they saw the same ionosphere. The first interesting results from a year`s study is that the authors do not see the same TID`s when looking at the two satellites. One conclusion they draw is that they do not see evidence of ionospheric winds.

Carlos, R.; Jacobson, A.; Massey, R.; Wu, G.

1994-09-01

104

Coronal magnetic field and the plasma beta determined from radio and multiple satellite observations  

E-print Network

We derived the coronal magnetic field, plasma density, and temperature from the observation of polarization and intensity of radio thermal free-free emission using the Nobeyama Radioheliograph (NoRH) and extreme ultraviolet (EUV) observations. We observed a post-flare loop on the west limb 11 April 2013. The line-of-sight magnetic field was derived from the circularly polarized free-free emission observed by NoRH. The emission measure and temperature were derived from the Atmospheric Imaging Assembly (AIA) onboard Solar Dynamics Observatory (SDO). The derived temperature was used to estimate the emission measure from the NoRH radio free-free emission observations. The derived density from NoRH was larger than that determined using AIA, which can be explained by the fact that the low temperature plasma is not within the temperature coverage of the AIA filters used in this study. We also discuss the other observation of the post-flare loops by the EUV Imager onboard the Solar Terrestrial Relations Observatory (...

Iwai, Kazumasa; Nozawa, Satoshi; Takahashi, Takuya; Sawada, Shinpei; Kitagawa, Jun; Miyawaki, Shun; Kashiwagi, Hirotaka

2014-01-01

105

Coronal magnetic field and the plasma beta determined from radio and multiple satellite observations  

NASA Astrophysics Data System (ADS)

We derived the coronal magnetic field, plasma density, and temperature from the observation of polarization and intensity of radio thermal free-free emission using the Nobeyama Radioheliograph (NoRH) and extreme ultraviolet (EUV) observations. We observed a post-flare loop on the west limb on 11 April 2013. The line-of-sight magnetic field was derived from the circularly polarized free-free emission observed by NoRH. The emission measure and temperature were derived from the Atmospheric Imaging Assembly (AIA) onboard Solar Dynamics Observatory (SDO). The derived temperature was used to estimate the emission measure from the NoRH radio free-free emission observations. The derived density from NoRH was larger than that determined using AIA, which can be explained by the fact that the low-temperature plasma is not within the temperature coverage of the AIA filters used in this study. We also discuss the other observation of the post-flare loops by the EUV Imager onboard the Solar Terrestrial Relations Observatory (STEREO), which can be used in future studies to reconstruct the coronal magnetic field strength. The derived plasma parameters and magnetic field were used to derive the plasma beta, which is a ratio between the magnetic pressure and the plasma pressure. The derived plasma beta is about 5.7 × 10-4 to 7.6 × 10-4 at the loop top region.

Iwai, Kazumasa; Shibasaki, Kiyoto; Nozawa, Satoshi; Takahashi, Takuya; Sawada, Shinpei; Kitagawa, Jun; Miyawaki, Shun; Kashiwagi, Hirotaka

2014-12-01

106

Holographic measurement on Medicina radio telescope using artificial satellites at 11 GHz  

NASA Astrophysics Data System (ADS)

The surface profile of the 32-m parabolic radiotelescope located in Medicina has been measured with the Misell phase-recovery technique using commercial geostationary satellites at 11 GHz and checked on H2O astronomical masers at 22 GHz as reference sources. The telescope is a parabolic reflector antenna operating in Cassegrain configuration and designed for observations up to the frequency of 23 GHz. The accuracy obtained with this technique is about 0.2 mm and the spatial resolution is 0.7 m.

Tarchi, D.; Comoretto, G.

1993-08-01

107

Interplanetary baseline observations of type 3 solar radio bursts. [by Helios satellites  

NASA Technical Reports Server (NTRS)

Simultaneous observations of type III radio bursts using spacecraft separated by several tenths of an AU were made using the solar orbiters HELIOS-A and -B. The burst beginning at 1922 UT on March 28, 1976, was located from the intersection of the source directions measured at each spacecraft, and from the burst arrival time differences. Wide baseline observations give the radial distance of the source at each observing frequency. Consequently, coronal electron densities and exciter velocity were determined directly, without the need to assume a density model as is done with single spacecraft observations. The separation of HELIOS-A and -B also provided the first measurements of burst directivity at low frequencies. For the March 28 burst, the intensity observed from near the source longitude (HELIOS-B) was significantly greater than from 60 W of the source (HELIOS-A).

Weber, R. R.; Fitzenreiter, R. J.; Novaco, J. C.; Fainberg, J.

1977-01-01

108

Satellite emission features in two Seyfert galaxies: New evidence that radio-quiet AGN possess subrelativistic winds  

NASA Astrophysics Data System (ADS)

Hubble Space Telescope (HST) Faint Object Spectrograph (FOS) spectra are presented for three bright Seyfert galaxies including one (PG 1351+64) which possesses blue-displaced absorption features in C IV, Si IV, N V, and Ly-alpha (but not in Mg II) similar to those seen at high redshift in the broad-absorption-line (BAL) quasi-stellar objects (QSOs). Several features of the absorptions in PG 1351+64, including variability seen in archival International Ultraviolet Explorer (IUE) data, confirm their similarity to the BAL clouds rather than to the 'associated absorber' phenomenon which they superficially resemble. In PG 1351+64 'satellite' emission lines (called herein E1 and E2) have been detected nearly symmetrically placed at +/- 4000 km/s around the Mg II emission line; this velocity is just larger than the most blue-displaced of the BALs, suggesting that these two phenomena are related. The satellite line luminosity, L(E1) approximately = (3 x 1041 erg/s)/sq. h75, requires a cloud emission measure ne2Vc approximately = (1 x 1064/cc)/sq. h75 at T approximately = 30,000 K. We believe the Mg II lines are produced by 50-90 km/s shocks driven into dense (approximately 106/cc, pre-shock) clouds by the ram pressure of a 0.1 solar mass/yr wind leaving the nucleus at velocity 4000 km/s. The detection of satellite lines in Mg II, the detection of the blue-shifted cloud in H-alpha and H-beta and the nondetection of this cloud in C IV restricts the cloud shocks to velocities vc less than or = 90 km/s and requires a cloud/wind density contrast greater than or = 103. In this model, the emitting clouds are located at distances of Reff approximately = 1018-19 cm from the nucleus and are entrained and shock-accelerated to approximately 4000 km/s. The possible detection of similar 'satellite' emission features in the non-BAL Seyfert, Ton 951, suggests that the subrelativistic wind that accelerates BAL clouds is a physical feature of many radio-quiet active galactic nuclei (AGN).

Stocke, John T.; Shull, Michael; Granados, Arno F.; Sachs, Elise R.

1994-10-01

109

Habitats used by black and surf scoters in eastern North America as determined by satellite radio telemetry  

USGS Publications Warehouse

Satellite radio telemetry was used to determine the movements and habitats of black scoters (Melanitta nigra) and surf scoters (Melanitta perspicillata) in eastern North America. A total of 21 surf scoters were instrumented during five years (2001-05) and 32 black scoters were instrumented during three years (2002-04) with implanted PTT 100 satellite transmitters (39 g) with external antenna. Nesting habitat of black scoters was more open than surf scoters (44% vs. 11%), whereas nesting habitat for surf scoters was located in more forested areas (66% vs. 20%). Locations of black scoters in breeding areas on average were at significantly higher latitude and lower elevations than sites used by surf scoters. Satellite telemetry determined that James Bay was the major molting area for male black and surf scoters, although some males molted along the coast of Labrador-Newfoundland. Black scoters instrumented on the Restigouche River, which is a major staging area, were widely distributed along the Atlantic Coast from Cape Cod to Georgia during winter. Major wintering areas for black scoters were Cape Cod (Martha's Vineyard and Nantucket Island), Long Island, and New Jersey. In these northern marine wintering areas, black scoters were located farther from shore (4.2 km) and in deeper water (8.3 m) than black scoters in more southern estuarine areas, where distance from shore was 3.1 km and water depth was 5.2 m. Surf scoters instrumented in Chesapeake Bay in late winter showed a strong tendency to return to the Bay the following winter after they had migrated to and from breeding areas. In Chesapeake Bay, black scoters and surf scoters were located mostly in mesohaline areas that had similar water depths (5.1 m vs. 7.5 m) and distances from shore (3.0 km vs. 2.9 km). Distance from shore and depth of water increased over time during the winter for both species. Updated information from the ARGOS Systems aboard the NOAA satellites on scoter movements was made accessible on the Patuxent Website.

Perry, M.C.; Kidwell, D.M.; Wells-Berlin, A. M.; Lohnes, E.J.R.; Olsen, G.H.; Osenton, P.C.

2005-01-01

110

Regimes of ionospheric turbulence from fractal analysis of satellite radio signal scintillations  

NASA Astrophysics Data System (ADS)

The paper describes a fractal analysis of the amplitude scintillations of signals from a geostationary satellite which can be used to characterize ionospheric turbulence and turbulence in the turbopause. The algorithm by Grassberger and Procaccia (1983) is employed to analyze the scintillations, and the drift velocity of the diffraction pattern and the spectral characteristics of the signal are calculated. Fractal dimensionality is estimated at 3.26-4.36 for three of the seven calculations, and the results are interpreted as evidence of two regimes of ionospheric turbulence at midlatitudes. Localized turbulent regions or sources are inferred in regimes for which reliable estimates of low dimensionality are determined. This and the high dimensionality of the second regime are consistent with the notion of horizontally homogeneous ionospheric turbulence.

Zvezdin, V. N.; Fridman, S. V.

1992-08-01

111

Satellite radio occultation investigations of internal gravity waves in the planetary atmospheres  

NASA Astrophysics Data System (ADS)

Internal gravity waves (IGWs) modulate the structure and circulation of the Earth’s atmosphere, producing quasi-periodic variations in the wind velocity, temperature and density. Similar effects are anticipated for the Venus and Mars since IGWs are a characteristic of stably stratified atmosphere. In this context, an original method for the determination of IGW parameters from a vertical temperature profile measurement in a planetary atmosphere has been developed [Gubenko et al., 2008, 2011, 2012]. This method does not require any additional information not contained in the profile and may be used for the analysis of profiles measured by various techniques. The criterion for the IGW identification has been formulated and argued. In the case when this criterion is satisfied, the analyzed temperature fluctuations can be considered as wave-induced. The method is based on the analysis of relative amplitudes of the wave field and on the linear IGW saturation theory in which these amplitudes are restricted by dynamical (shear) instability processes in the atmosphere. When the amplitude of an internal wave reaches the shear instability threshold, energy is assumed to be dissipated in such a way that the IGW amplitude is maintained at the instability threshold level as the wave propagates upwards. We have extended the developed technique [Gubenko et al., 2008] in order to reconstruct the complete set of wave characteristics including such important parameters as the wave kinetic and potential energy per unit mass and IGW fluxes of the energy and horizontal momentum [Gubenko et al., 2011]. We propose also an alternative method to estimate the relative amplitudes and to extract IGW parameters from an analysis of perturbations of the Brunt-Vaislala frequency squared [Gubenko et al., 2011]. An application of the developed method to the radio occultation (RO) temperature data has given the possibility to identify the IGWs in the Earth's, Martian and Venusian atmospheres and to determine the magnitudes of key wave parameters such as the intrinsic frequency, amplitudes of vertical and horizontal wind velocity perturbations, vertical and horizontal wavelengths, intrinsic vertical and horizontal phase (and group) speeds, kinetic and potential energy per unit mass, vertical fluxes of the wave energy and horizontal momentum. Vertical profiles of temperature retrieved from RO measurements of the CHAMP (Earth), Mars Global Surveyor (Mars), Magellan and Venus Express (Venus) missions are used and analyzed to identify discrete or “narrow spectral” wave events and to determine IGW characteristics in the Earth’s, Martian and Venusian atmospheres. This work was partially supported by the RFBR grant 13-02-00526-? and Program 22 of the RAS Presidium. References. Gubenko V.N., Pavelyev A.G., Andreev V.E. Determination of the intrinsic frequency and other wave parameters from a single vertical temperature or density profile measurement // J. Geophys. Res. 2008. V. 113. No.D08109, doi:10.1029/2007JD008920. Gubenko V.N., Pavelyev A.G., Salimzyanov R.R., Pavelyev A.A. Reconstruction of internal gravity wave parameters from radio occultation retrievals of vertical temperature profiles in the Earth’s atmosphere // Atmos. Meas. Tech. 2011. V. 4. No.10. P. 2153-2162, doi:10.5194/amt-4-2153-2011. Gubenko V.N., Pavelyev A.G., Salimzyanov R.R., Andreev V.E. A method for determination of internal gravity wave parameters from a vertical temperature or density profile measurement in the Earth’s atmosphere // Cosmic Res. 2012. V. 50. No.1. P. 21-31, doi: 10.1134/S0010952512010029.

Kirillovich, Ivan; Gubenko, Vladimir; Pavelyev, Alexander

112

INSTRUMENTS AND METHODS OF INVESTIGATION Ice satellites of planets of the Solar System and the on-orbit radio detection of ultrahigh-energy particles  

NASA Astrophysics Data System (ADS)

The problem of detecting nature's most energetic particles—cosmic rays and neutrinos—is reviewed. Prospects for using orbital radio detectors for these highest-energy particles are examined. Apertures are calculated for space experiments using the Moon and similar-sized ice satellites of planets of the Solar System as targets for the interaction of cosmic-ray particles and neutrinos. A comparative analysis shows that using the Moon as a target is the most promising scenario.

Gusev, G. A.; Lomonosov, B. N.; Ryabov, Vladimir A.; Chechin, V. A.

2010-12-01

113

User applications unique to mobile satellites  

NASA Astrophysics Data System (ADS)

As AMSC enters the market with its mobile satellite services, it faces a sophisticated user group that has already experimented with a wide range of communications services, including cellular radio and Ku-band satellite messaging. AMSC's challenge is to define applications unique to the capabilities of its dedicated L band satellite and consistent with the provisions outlined in its FCC license. Through a carefully researched approach to its three main markets (aeronautical, land mobile, and maritime) AMSC is discovering a wellspring of interest in corporate and general aviation, trucking companies, pipeline monitoring and control companies, maritime management firms, telecommunications companies, and government agencies. A general overview is provided of AMSC's FCC license and corporate history, and the specific applications unique to each user group is discussed.

Castiel, David

114

User applications unique to mobile satellites  

NASA Technical Reports Server (NTRS)

As AMSC enters the market with its mobile satellite services, it faces a sophisticated user group that has already experimented with a wide range of communications services, including cellular radio and Ku-band satellite messaging. AMSC's challenge is to define applications unique to the capabilities of its dedicated L band satellite and consistent with the provisions outlined in its FCC license. Through a carefully researched approach to its three main markets (aeronautical, land mobile, and maritime) AMSC is discovering a wellspring of interest in corporate and general aviation, trucking companies, pipeline monitoring and control companies, maritime management firms, telecommunications companies, and government agencies. A general overview is provided of AMSC's FCC license and corporate history, and the specific applications unique to each user group is discussed.

Castiel, David

1990-01-01

115

Concept and Analysis of a Satellite for Space-Based Radio Detection of Ultra-High Energy Cosmic Rays  

NASA Astrophysics Data System (ADS)

We present a concept for on-orbit radio detection of ultra-high energy cosmic rays (UHECRs) that has the potential to provide collection rates of ~100 events per year for energies above 10^20 eV. The synoptic wideband orbiting radio detector (SWORD) mission's high event statistics at these energies combined with the pointing capabilities of a space-borne antenna array could enable charged particle astronomy. The detector concept is based on ANITA's successful detection UHECRs where the geosynchrotron radio signal produced by the extended air shower is reflected off the Earth's surface and detected in flight.

Romero-Wolf, Andrew; Gorham, P.; Booth, J.; Chen, P.; Duren, R. M.; Liewer, K.; Nam, J.; Saltzberg, D.; Schoorlemmer, H.; Wissel, S.; Zairfian, P.

2014-01-01

116

Radio data transmission for SCADA  

SciTech Connect

Enron has used such wireless systems as meteor burst radio, 952 MHz multiple address radio, VSAT and L-band satellite, cellular radio and ACSB radio. The company's experience with meteor burst radio communications is discussed in this paper. It indicates good system reliability and consequently all back-up telephone lines have been removed from sites using this system.

Frasier, W.E. (Enron Corp., Houston, TX (US))

1989-09-01

117

47 CFR 25.214 - Technical requirements for space stations in the satellite digital audio radio service and...  

Code of Federal Regulations, 2012 CFR

...MHz and 2332.5-2345.0 MHz; (3) Satellite DARS licensees may reduce their assigned bandwidth occupancy to provide telemetry beacons in their exclusive frequency assignments; (4) Each licensee may employ cross polarization within its...

2012-10-01

118

47 CFR 25.214 - Technical requirements for space stations in the Satellite Digital Audio Radio Service and...  

Code of Federal Regulations, 2013 CFR

...MHz and 2332.5-2345.0 MHz; (3) Satellite DARS licensees may reduce their assigned bandwidth occupancy to provide telemetry beacons in their exclusive frequency assignments; (4) Each licensee may employ cross polarization within its...

2013-10-01

119

Demonstration of the use of the Doppler Orbitography and Radio positioning Integrated by Satellite (DORIS) measurements to validate GPS ionospheric imaging  

NASA Astrophysics Data System (ADS)

There is a lack of independent ionospheric data that can be used to validate GPS imaging results at mid latitudes over severe storm times. Doppler Orbitography and Radio positioning Integrated by Satellite (DORIS), a global network of dual-frequency ground to satellite observations, provides this missing data and here is employed as verification to show the accuracy of the ionospheric GPS images in terms of the total electron content (TEC). In this paper, the large-scale ionospheric structures that appeared during the strong geomagnetic storm of 20 November 2003 are reconstructed with a GPS tomographic algorithm, known as MIDAS, and validated with DORIS TEC measurements. The main trough shown in an extreme equatorward position in the ionospheric imaging over mainland Europe is confirmed by DORIS satellite measurements. Throughout the disturbed day, the variations of relative slant TECs between DORIS data and MIDAS results agree quite well, with the average of the mean differences about 2 TECu. We conclude that as a valuable supplement to GPS data, DORIS ionospheric measurements can be used to analyse TEC variations with a relatively high resolution, ˜10 s in time and tens of kilometres in space. This will be very helpful for identification of some highly dynamic structures in the ionosphere found at mid-latitudes, such as the main trough, TID (Travelling Ionospheric Disturbances) and SED (Storm Enhanced Density), and could be used as a valuable auxiliary data source in ionospheric imaging.

Yin, Ping; Mitchell, Cathryn N.

2011-08-01

120

Demand Assignment Multiple Access and Dynamic Channel Allocation Strategies for Integrating Radio Dispatch and Telephone Services Over Mobile Satellite Systems  

Microsoft Academic Search

The authors discuss the performance analyses of a novel demand assignment multiple access (DAMA) scheme addressing the special characteristics of the mobile radio service (MRS), and a new method for dynamically allocating a common pool of channels to both MRS and mobile telephone service (MTS) to improve channel utilization. The new DAMA scheme makes use of call queuing, batch processing,

Chris J. Powell; Victor C. M. Leung

1992-01-01

121

Capacity of a MultiBeam, Multi-Satellite CDMA Mobile Radio Network with Interference-Mitigating Receivers  

Microsoft Academic Search

More and more interference-mitigating algorithms are being investigated in an attempt to increase the capacity of code-division multiple-access radio networks. At the moment, the main question about interference-resilient receivers is: Do they really bring forth the capacity increase they promise on theoreti- cal grounds? The aim of this study is to give a preliminary answer to such a question, through

Riccardo De Gaudenzi; Filippo Giannetti; Marco Luise

1997-01-01

122

Atmospheric sounding by global navigation satellite system radio occultation: An analysis of the negative refractivity bias using CHAMP observations  

Microsoft Academic Search

Validation studies of current GPS radio occultation experiments using meteorological analyses consistently report on a negative refractivity bias in the lower troposphere. End-to-end simulations including the GPS receiver's signal tracking process suggest that receiver-induced phase deviations contribute to this observed bias. We propose a heuristic retrieval algorithm based on the canonical transform and the sliding spectral technique, which seems less

G. Beyerle; J. Wickert; T. Schmidt; C. Reigber

2004-01-01

123

Migration and wintering areas of American Bitterns (Botaurus lentiginosus) that summer in central North America as determined by satellite and radio telemetry, 1998-2003  

USGS Publications Warehouse

Twenty adult male American Bitterns (Botaurus lentiginosus) were marked on summer range in central North America with satellite tracking Platform Transmitter Terminals (PTTs) to document migration routes and wintering range. Nineteen complete fall migration routes were documented for 17 individuals. Of the successful migrations, 63% (n = 12) went to southern Florida, 32% (n = 6) to southern Louisiana, and 5% (n = 1) to the Gulf coast of Texas. Spring migrations for nine birds were documented, and 78% (n = 7) showed fidelity to breeding range. Two complete migrations for two individuals were documented, and they demonstrated fidelity to winter range. The longest, fastest movement documented was 2,300 km in less than 74 hr. Extensive, post-breeding dispersal was not observed in the adult male American Bitterns in this study. Six male American Bitterns were marked with PTTs on winter range in Florida and Texas. Spring migration for these birds was documented to Nebraska, North Dakota, Saskatchewan, Manitoba and Ontario. Sixty-seven American Bitterns were marked with Very High Frequency radio transmitters on summer ranges, and 16% (n = 11) were located on wintering grounds used by the satellite-tracked birds, further documenting the importance of the Everglades and the Louisiana coast as winter habitat for American Bitterns that breed in Central North America.

Huschle, Guy; Toepfer, John E.; Douglas, David C.

2013-01-01

124

S-band dual-path dual-polarized antenna system for satellite digital audio radio service (SDARS) application  

Microsoft Academic Search

This paper presents a novel compact dual-polarized antenna system for S-band satellite digital broadcasting receivers. The demonstrated antenna system consists of a low form factor dual-polarized antenna pair and two-stage low-noise amplifiers (LNAs) integrated with each antenna. One antenna is a low-profile annular ring patch antenna having a 90° phase-delay element for circular polarization (CP) and the other antenna is

Young-Pyo Hong; Jung-Min Kim; Soon-Chul Jeong; Dong-Hyun Kim; Mun-Ho Choi; Yongshik Lee; Jong-Gwan Yook

2006-01-01

125

Theory of intense radio waves in an underdense ionosphere: application to solar power satellite transmissions. Final report  

SciTech Connect

The instabilities in the F-region plasma are investigated that can be created by the passage of a solar power satellite beam (2.45 Ghz frequency, at a power flux of 23 mW/cm/sup 2/) at frequencies much higher than the cut-off plasma frequency of the ionosphere. The threshold geometry and frequency and intensity scaling laws are calculated for the thermal self-focusing instability, and its saturation level is estimated. The possibility is considered of scaled experiments at HF power to detect the thermal self-focusing instability for an underdense ionosphere. Other experimental possibilities are discussed in terms of the scaling laws. (LEW)

Goldman, M V

1980-11-01

126

Two-component model of topside ionosphere electron density profiles retrieved from Global Navigation Satellite Systems radio occultations  

NASA Astrophysics Data System (ADS)

A simple model for the topside ionosphere region is introduced and applied to fit radio-occultation-retrieved electron density profiles for altitudes above the F2 peak. The model considers two isothermal components representing the population of the O+ (ionosphere component) and the H+(protonosphere component) ions. The purpose of the model is to achieve an accurate fit of the observed profiles in the topside ionosphere region while, at the same time, allowing a direct and simple derivation of two important ionospheric parameters, namely the O+vertical scale height and the upper transition height. Covering a time period of 1 year, the fits with the two-component model function are compared with those achieved with one-component functions commonly used in the literature and it is shown that the former provides significantly better fits than the later, with more than a factor of two improvement. The model predictions concerning: the correlation between the O+vertical scale height and the upper transition height, the altitude dependence of the vertical scale height of the electron density, and the quantitative contribution of the protonosphere to the total electron content are examined and shown to be consistent with the observations and with previous studies. It is concluded that the model provides a realistic description of the vertical distribution of the two main ion constituents of the topside ionosphere.

González-Casado, Guillermo; Juan, J. Miguel; Hernández-Pajares, Manuel; Sanz, Jaume

2013-11-01

127

Radio Galaxies.  

ERIC Educational Resources Information Center

Provides background information on radio galaxies. Topic areas addressed include: what produces the radio emission; radio telescopes; locating radio galaxies; how distances to radio galaxies are found; physics of radio galaxies; computer simulations of radio galaxies; and the evolution of radio galaxies with cosmic time. (JN)

Downes, Ann

1986-01-01

128

The GNSS polarimetric radio-occultation technique to sense precipitation events: a new concept to be tested aboard PAZ Low Earth Satellite  

NASA Astrophysics Data System (ADS)

The Radio Occultation and Heavy Precipitation (ROHP) experiment, to be conducted aboard the Spanish PAZ satellite, consists of a radio occultation (RO) mission provided with dual-polarization capabilities. The research with polarimetric RO data has the goal of assessing the capabilities and limitations of this technique to infer profiles of heavy precipitation. The technique aims to provide vertical profiles of precipitation simultaneously to the vertical profiles of thermodynamic parameters (standard RO products) perfectly collocated both in space and time. If successful, the polarimetric RO will represent the first technique able to provide these complementary information on precipitation. This is a relevant input for studies on heavy and violent rainfall events, which being poorly represented by the current-generation of Numerical Weather Prediction and General Circulation Models appear to be difficult to forecast on all time-scales. The Low Earth Orbiter hosting this experiment, to be launched in 2013, will orbit at 500 km altitude in a near-Polar orbit. The Radio Occulation payload includes a RO GNSS receiver and a dual polarization (H/V) limb oriented antenna to capture the signals of setting GNSS transmitters. NOAA and UCAR participate in the ground-segment of the radiometric experiment to enable near-real time dissemination of the level-1 standard RO products. The space-based GNSS RO technique scans the atmosphere vertically at fine resolution (close to 300 meter in the troposphere) by precisely measure the delay between a GNSS transmitter and a GNSS receiver aboard a Low Earth Orbiter, when the former is setting below or rising above the Earth limb. The standard, thermodynamical, products are extracted from the excess delay induced by the atmosphere at different layers. This presentation will not focus on this well-established application, but a novel concept using polarimetry to also retrieve rain information. The precipitation-measurement principle is based on the asymmetry between the vertical and horizontal axis of the rain droplets, especially when intense rates of precipitation occur. As a first approximation, the RO signals propagate across the precipitation-volume tangentially, that is, along the local horizontal axis of the droplets. Forward scattering models have been implemented to quantify the sensitivity of L-band signals to different rain rates and precipitation extension being crossed by the signals. The observable considered so far is the polarimetric phase shift: difference between the phase delay suffered by the H- and V-polarizations. Real RO events have been collocated with TRMM precipitation data. The path traveled by the RO signal under a given altitude has been projected on the TRMM grid of observations, to obtain a profile of the precipitation being crossed by the RO link at a given moment of the occultation event. This mechanism has been used to feed the propagation models and thus estimate the polarimetric phase shift that each precipitation event would have induced into the occultation observation. This simulation exercise permits to determine the detectability thresholds and the expected statistics of such collocated events. Methodology and results will be presented.

Tomás, Sergio; Oliveras, Santi; Cardellach, Estel; Rius, Antonio

2013-04-01

129

Corporate marketing : Integrating corporate identity, corporate branding, corporate communications, corporate image and corporate reputation  

Microsoft Academic Search

Purpose – The aims of the paper are to examine the nascent area of corporate marketing. Design\\/methodology\\/approach – The paper draws on some of the key literature relating to the history of marketing thought. Findings – The study reiterates the case that corporate identity, corporate branding, corporate communications, and corporate reputation should be integrated under the umbrella title of corporate

John M. T. Balmer; Stephen A. Greyser

2006-01-01

130

Radio and Localism: Has the FCC Dropped the Ball?  

Microsoft Academic Search

Although no news of the FCC task force initiative on localism came forth between 2004 and 2006, members of Congress have taken an interest in the effects of localism in radio broadcasting. This interest can be attributed to the view that radio consolidation has minimized local radio service. As well, satellite-delivered radio has begun to encroach on local radio as

Samuel J. Sauls; Danny Greer

2007-01-01

131

Interferometric Observations of Geosynchronous Satellites  

E-print Network

In recent years, a large number of geosynchronous satellites are being planned to provide augmentation services for enhancing the precision to global positioning systems, e.g., GPS, in applications such as aircraft landing. In this paper, we present a scheme for co-locating passive satellite observational facilities with a radio astronomy facility to open a new possibility of providing valuable data for radio astronomical imaging, ionospheric studies and satellite orbit estimation.

Subrahmanya, C R; Somashekar, R

2011-01-01

132

A Question of Interference: FM Radio's Early Struggle for Survival 1934-1945.  

ERIC Educational Resources Information Center

This paper explores FM radio's struggle for survival in the 1940s, focusing primarily on the impact of Federal Communications Commission (FCC) decision making and on the influence and activities of the well-established radio corporations, primarily the Radio Corporation of America (RCA). It describes the invention of FM radio by Edwin H. Armstrong…

Zenaty, Jayne W.

133

The strategic corporate intelligence and transformational marketing model  

Microsoft Academic Search

Reference to the strategic marketing and corporate intelligence interface is made explicit in this paper, and various contributions to the field of competitive intelligence are highlighted. A conceptual model, known as the strategic corporate intelligence and transformational marketing (SATELLITE) model is outlined, and can be used by corporate intelligence staff to provide better marketing intelligence. The SATELLITE model provides a

Peter R. J. Trim

2004-01-01

134

Division X: Radio Astronomy  

Microsoft Academic Search

There have been important advances in radio astronomy in the last three years. New discoveries both at the galactic and extragalactic scale have been reported over this period and we highlight here several of them. The outstanding results of the Wilkinson Microwave Anisotropy Probe satellite, allowing an accurate determination of the main cosmological constants, are certainly among the most important.

Luis F. Rodríguez; Ren-Dong Nan; Philip J. Diamond; Gloria Dubner; Michael Garrett; Anne Green; Masato Ishiguro; W. Miller Goss; Russ Taylor; Lucia Padrielli; A. Pramesh Rao; José M. Torrelles; Jean L. Turner

2007-01-01

135

Possibility of Frequencies Sharing by Telecommunication Systems on the Basis of High-Altitude Platforms and Conventional Fixed Systems, Fixed Satellite and Radio-Astronomical Service Systems  

Microsoft Academic Search

Presented in this paper is the use of frequency bands 27.5...28.35 GHz, 31 ...31.3 GHz, 47.2...47.5 GHz and 47.9...48.2 GHz HAPS within the frameworks of FS, as well as technical and procedural questions regarding sharing HAPS and radio systems of FS, FSS, RAS and EESS within above specified frequencies bands

S. A. Kravchuk

2006-01-01

136

Telemetry Data Collection from Oscar Satellite  

NASA Technical Reports Server (NTRS)

This paper discusses the design, configuration, and operation of a satellite station built for the Center for Space Telemetering and Telecommunications Laboratory in the Klipsch School of Electrical and Computer Engineering Engineering at New Mexico State University (NMSU). This satellite station consists of a computer-controlled antenna tracking system, 2m/70cm transceiver, satellite tracking software, and a demodulator. The satellite station receives satellite,telemetry, allows for voice communications, and will be used in future classes. Currently this satellite station is receiving telemetry from an amateur radio satellite, UoSAT-OSCAR-11. Amateur radio satellites are referred to as Orbiting Satellites Carrying Amateur Radio (OSCAR) satellites as discussed in the next section.

Haddock, Paul C.; Horan, Stephen

1998-01-01

137

Copyright Quick Guide Television and Radio Broadcasts  

E-print Network

to copy and communicate television and radio broadcasts for educational purposes. This includes makingCopyright Quick Guide Television and Radio Broadcasts Overview The University has extensive rights ­ this includes free-to-air, satellite and cable television broadcasts, along with radio broadcasts. As a result

Blows, Mark

138

Progress toward a full scale mobile satellite system for Canada  

NASA Astrophysics Data System (ADS)

The MSAT satellite, planned for launch in early 1994, will provide full scale, satellite based, mobile voice and data communication services to Canada. The MSAT system will provide mobile telephone, mobile radio and mobile data services to customers on the move in any part of North America. The Telesat Mobile Inc. (TMI) satellite will be backed up by a similar satellite to be operated by the American Mobile Satellite Corporation (AMSC) in the United States. An early entry mobile data service was inaugurated in the second quarter of 1990 using channels leased from INMARSAT on Marisat or Marecs-B. The baseline TMI system is described, beginning with the MSAT satellite under contract. The network architecture and the control system that are under development to support the mobile services are discussed. Since it is clearly desirable to have a North American system, such that customers may buy a mobile earth terminal (MET) from a number of qualified suppliers and be able to use it either in Canada or the U.S., TMI and AMSC are cooperating closely in the development of the space and ground segments of the system. The time scale for the procurement of all the elements of the systems is discussed.

Roscoe, Orest S.

139

Corporate Environmental Social Responsibility: Corporate \\  

Microsoft Academic Search

This article focuses on the extent to which unenforceable voluntary initiatives undertaken by corporations can change corporate behavior to make businesses more environmentally responsible, i.e. not only comply with the law, but to do more than the law actually requires of them. These initiatives, loosely gathered under the umbrella of a movement called corporate social responsibility (CSR), are often proposed

Hope M. Babcock

2010-01-01

140

The ionosphere as a focusing lens - A case study involving simultaneous type III solar radio storm measurements from the ISIS 1 and 2 and ISEE 3 satellites  

NASA Technical Reports Server (NTRS)

The possibility of using terrestrial ionospheric focusing to improve the directivity of electric dipoles on space missions has been investigated by comparing simultaneous observations of a solar radio storm by the ISIS 1 and ISIS 2 spacecraft, in near earth orbit, and the ISEE 3 spacecraft located beyond the magnetosphere. To this end, a three-dimensional ray tracing in a spherically stratified ionosphere has been carried out for conditions appropriate to the observations by the ISIS spacecraft of a solar radio storm in September 1983. The procedure allows Poynting flux spectral densities measured on ISIS to be converted to spectral densities well outside the ionosphere where they can be compared directly with simultaneous observations on ISEE 3. The results demonstrate good agreement over their common observing frequency range (1-2 MHz).

James, H. G.; Benson, R. F.; Fainberg, J.; Stone, R. G.

1990-01-01

141

Differential spectral attenuation measurements at microwaves in a LEO-LEO satellites radio occultation geometry: a novel approach for limiting scintillation effects in tropospheric water vapor measurements  

Microsoft Academic Search

The DSA (Differential Spectral Attenuation) approach, presented in a companion paper in this conference's proceedings, has the potential to provide the total content of water vapor (IWV, Integrated Water Vapor) along the propagation path between two Low Earth Orbiting (LEO) satellites. The interest towards the DSA, based on the ratio of simultaneous measurements of the total attenuation at two relatively

Luca Facheris; Enrica Martini; Fabrizio Cuccoli; Fabrizio Argenti

2004-01-01

142

Radio Journalism.  

ERIC Educational Resources Information Center

This book, a how-to-do-it guide for the novice and the professional alike, deals with several aspects of radio journalism: producing documentaries, preparing and announcing radio news, ethics and responsibility, regulation of radio journalism, and careers. It traces the history and growth of radio news, shows its impact on the public, and…

Bittner, John R.; Bittner, Denise A.

143

Magnetospherically reflected, specularly reflected, and backscattered whistler mode radio-sounder echoes observed on the IMAGE satellite: 2. Sounding of electron density, ion effective mass (meff), ion composition (H+, He+, O+), and density irregularities along the geomagnetic field line  

NASA Astrophysics Data System (ADS)

A companion paper by Sonwalkar et al. (2011) provided new details of whistler mode radio sounding of the altitude range below ˜5000 km by the Radio Plasma Imager (RPI) instrument on the IMAGE satellite. That paper presented frequency-vs- group time delay records of echoes whose raypaths either 1) reversed direction through refraction at altitudes above the ionosphere where the wave frequency was approximately equal to the local lower hybrid resonance frequency flh (magnetospherically reflected or MR echoes), or 2) returned to IMAGE from reflection points along the sharp lower boundary of the ionosphere at ˜90 km (obliquely incident (OI) or normally incident (NI) specularly reflected (SR) echoes). The MR and OI echo paths were shown to form narrow loops, while the NI echo followed the same raypath down and back. Furthermore, the echoes were found to be discrete or broadened in time delay either by multipath propagation or by scattering from field aligned irregularities (FAIs). We begin with a direct interpretive approach, employing a combination of refractive index diagrams, ray tracings, and a plasma density model to predict the detailed frequency-vs-time properties of echoes detected when the sounder is operated over a wide range of whistler mode frequencies (typically 6 kHz to 63 kHz) and the satellite is either above or below the altitude of the maximum flh along the geomagnetic field line B0 in the upper ionosphere. We then consider the inverse problem, estimation of the parameters of the prevailing plasma density model from the observed echo properties. Thanks to variations in the sensitivity of the various echo forms to the altitude profiles of electron density and ion effective mass meff, we use the observed frequency-vs- group time delay (tg - f) details of simultaneously received MR and SR echoes to infer the properties of a diffusive equilibrium model of the plasma, including estimates of the ion composition in the important transition region from the O+-dominated ionosphere to the light ion regime above. Our results on electron density and ion composition measurements are in general agreement with those obtained from in situ measurements on the IMAGE and DMSP-F15 satellites, with bottomside sounding results from nearby Ionosondes, and with values obtained from the IRI-2007 model. We also demonstrate a method of estimating the scale sizes and locations of FAIs located along or near WM echo paths.

Sonwalkar, V. S.; Reddy, A.; Carpenter, D. L.

2011-11-01

144

Transport Layer Coding for Satellite-Based Audio and Multimedia Services to Vehicular Terminals in Ku-Band  

Microsoft Academic Search

Satellite radio for vehicles is normally hampered by the problem of the shadowing of the line-of-sight between satellite and receiver. One possible way to overcome this challenge is to provide a new type of radio service, hereafter referred to as personalized satellite radio, in alternative to the streaming approach used for traditional radio: individual audio and multimedia files are broadcasted

Matteo Berioli; Harald Ernst; Sandro Scalise; Rolv Midthassel; Christophe Loeillet

2008-01-01

145

Corporal Punishment  

Microsoft Academic Search

It is vital to study and understand the underlying conditions that support and maintain the almost universal positive attitudes about the use of corporal punishment with children. Corporal punishment is a form of violence against children that affects child development and may possibly be a link to later violent behavior. Currently, the scientific community is in great debate regarding the

Carolyn Hilarski

2004-01-01

146

Corporate Social Responsibility and Corporate Citizenship: Towards Corporate Accountability  

Microsoft Academic Search

f you were a newcomer in the field of business and social issues and you started browsing academic literature, surely you would be bewildered by a number of different terms and definitions that imply similar or identical meanings: corporate social responsi- bility, public responsibility, corporate social responsibilities, corporate societal responsibility, corporate social responsiveness, corporate social performance, corporate citizenship, business citizenship,

CARMEN VALOR

2005-01-01

147

Educational Radio.  

ERIC Educational Resources Information Center

Examines the effectiveness of the radio in education and the crucial role of the radio in distance education in first half of the 20th century; dramatic social changes in the 1960s that led to a review of educational institutions and of educational media; and the radio today as a neglected but inexpensive medium of communication that should be…

Arafeh, Sousan

1999-01-01

148

Satellite (IRLS) tracking of elk  

NASA Technical Reports Server (NTRS)

The practicability of tracking free roaming animals in natural environments by satellite systems is reported. Satellite systems combine continuous tracking with simultaneous monitoring of physiological and environmental parameters through a combination of radio tracking and biotelemetric ground systems that lead to a better understanding of animal behavior and migration patterns.

Buechner, H. K.

1972-01-01

149

26 CFR 1.955-5 - Definition of less developed country corporation.  

Code of Federal Regulations, 2013 CFR

... Foreign corporation A is formed on November 1, 1963, to engage in the business of manufacturing and selling radios in Brazil, a less developed country as of November 1, 1963. Corporation A uses the calendar year as a taxable year....

2013-04-01

150

26 CFR 1.955-5 - Definition of less developed country corporation.  

... Foreign corporation A is formed on November 1, 1963, to engage in the business of manufacturing and selling radios in Brazil, a less developed country as of November 1, 1963. Corporation A uses the calendar year as a taxable year....

2014-04-01

151

26 CFR 1.955-5 - Definition of less developed country corporation.  

Code of Federal Regulations, 2011 CFR

... Foreign corporation A is formed on November 1, 1963, to engage in the business of manufacturing and selling radios in Brazil, a less developed country as of November 1, 1963. Corporation A uses the calendar year as a taxable year....

2011-04-01

152

26 CFR 1.955-5 - Definition of less developed country corporation.  

Code of Federal Regulations, 2012 CFR

... Foreign corporation A is formed on November 1, 1963, to engage in the business of manufacturing and selling radios in Brazil, a less developed country as of November 1, 1963. Corporation A uses the calendar year as a taxable year....

2012-04-01

153

Corporal punishment.  

PubMed

Pediatricians differ on the optimal ways to discipline children. The major controversy surrounds the use of corporal punishment. In an effort to resolve this controversy, the American Academy of Pediatrics (AAP) cosponsored a conference entitled "The Short and Long-Term Consequences of Corporal Punishment" in February 1996. This article reviews scientific literature on corporal punishment and summarizes the proceedings from the conference. The authors conclude that, although the research data are inadequate to resolve the controversy, there are areas of consensus. Practitioners should assess the spanking practices of the parent they see and counsel parents to avoid those that are, by AAP consensus, dangerous, ineffective, or abusive. PMID:9568019

Bauman, L J; Friedman, S B

1998-04-01

154

Mobile satellite service communications tests using a NASA satellite  

NASA Technical Reports Server (NTRS)

Emerging applications of commercial mobile satellite communications include satellite delivery of compact disc (CD) quality radio to car drivers who can select their favorite programming as they drive any distance; transmission of current air traffic data to aircraft; and handheld communication of data and images from any remote corner of the world. Experiments with the enabling technologies and tests and demonstrations of these concepts are being conducted before the first satellite is launched by utilizing an existing NASA spacecraft.

Chambers, Katherine H.; Koschmeder, Louis A.; Hollansworth, James E.; ONeill, Jack; Jones, Robert E.; Gibbons, Richard C.

1995-01-01

155

Firefighters' Radios  

NASA Technical Reports Server (NTRS)

Public Technology Inc. asked for NASA assistance to devise the original firefighter's radio. Good short-range radio communications are essential during a fire to coordinate hose lines, rescue victims, and otherwise increase efficiency. Useful firefighting tool is lower cost, more rugged short range two-way radio. Inductorless electronic circuit replaced inductances and coils in radio circuits with combination of transistors and other low-cost components. Substitution promises reduced circuit size and cost. Enhanced electrical performance made radio more durable and improved maintainability by incorporating modular construction.

1976-01-01

156

Solar Power Satellite (SPS) pilot beam and communication link subsystem investigation study, phase 1. [ionospheric propagation, radio frequency interference, and microwave transmission  

NASA Technical Reports Server (NTRS)

A preliminary engineering model of ionospheric interactions with the pilot beam was established and used to demonstrate that the dual frequency baseline pilot beam system might not be viable in the presence of an unstable transmission path. Alternate approaches to remove this difficulty are described. Although ionospheric fluctuations will not significantly degrade beam pointing or raise the sidelobe levels, they will reduce transmission efficiency by upwards of 25%. Mitigating strategies to substantially reduce this effect are proposed. Based on the Klystron noise spectrum, the pilot beam transmitter power was determined as a function of frequency offset from the power beam carrier frequency. The RFI from the pilot beam, on the ground and at geosynchronous orbit is shown. Noise levels on the earth's surface due to the SPS are presented as a function of frequency and the number of SPS systems. Analysis of the communication subsystem indicates that a standard telemetry line of 1.544 MB/s would satisfy both voice and data link requirements. Additional links would be required for TV and radio transmissions.

1979-01-01

157

Multinational Corporations.  

National Technical Information Service (NTIS)

Contents: The corporation; Relations with home and host governments; Economic impact--(Balance of payments, Foreign economic policy, Foreign economic relations); Political impact (Expropriation, Foreign policy, Foreign relations, International law).

1975-01-01

158

Toshiba Corporation  

SciTech Connect

This paper discusses how Toshiba Corporation has been involved in research for fusion nuclear technology since the 1960s. The authors focus on studies for high heat flux components, remote systems technology, fuel circulation systems, and safety analysis.

Sawada, Y.; Kakizawa, K. (Toshiba Corp., Heavy Apparatus Engineering Lab., 2-4 Suehiro, Tsurumi Yokohama 230 (JP))

1990-03-01

159

Satellite networks for education.  

NASA Technical Reports Server (NTRS)

Consideration of satellite-based educational networking. The characteristics and structure of networks are reviewed, and pressures within the educational establishment that are providing motivation for various types of networks are discussed. A number of studies are cited in which networking needs for educational sectors and services are defined. The current status of educational networking for educational radio and television, instructional television fixed services, inter- and intrastate educational communication networks, computer networks, cable television for education, and continuing and proposed educational experiments using NASA's Applications Technology Satellites is reviewed. Possible satellite-based educational telecommunication services and three alternatives for implementing educational satellite systems are described. Some remarks are made concerning public policy aspects of future educational satellite system development.

Singh, J. P.; Morgan, R. P.; Rosenbaum, F. J.

1972-01-01

160

Corporate Information  

NSDL National Science Digital Library

Gregory Regnery has put together an extensive list of sites with information on corporations from around the world. The aim of the site is to allow people to find information about a particular company quickly. Hence, the web sites featured here consist mainly of business directories and stock exchanges. Both domestic and international sources of corporate information are available; resources are sorted by country. This web site also contains a list of definitions for security identifiers and company extensions used by other countries.

Regnery, George M.

1998-01-01

161

History of radio navigation in Siberia  

Microsoft Academic Search

The stages of development of radio-technical industry in Krasnoyarsk region are reviewed. The main results of development of high-precision ground based and satellite radionavigation systems and devices widely used for object locating and sensing are given.

V. I. Kokorin; V. N. Bondarenko; R. G. Galeyev

2009-01-01

162

Description of the AMSC mobile satellite system  

Microsoft Academic Search

The American Mobile Satellite Corporation will provide a full range of mobile satellite services through a mobile satellite system dedicated to mobile use in the United States. This paper provides a summary of the system architecture with descriptions of each of the major system elements. The elements are the space segment, network control system, mobile earth terminals and feeder-link earth

W. B. Garner

1990-01-01

163

Public Radio/Television Survey: Report 2: Public Radio On-Air Fund Raising.  

ERIC Educational Resources Information Center

The second in a series of four, this report describes part of a national study commissioned by the Corporation for Public Broadcasting to investigate audience awareness of public radio, reaction to on-air fund raising and programing on public radio, and audience reactions to on-air fund raising by public television stations. Specifically, reaction…

Corporation for Public Broadcasting, Washington, DC.

164

User applications unique to mobile satellites  

Microsoft Academic Search

As AMSC enters the market with its mobile satellite services, it faces a sophisticated user group that has already experimented with a wide range of communications services, including cellular radio and Ku-band satellite messaging. AMSC's challenge is to define applications unique to the capabilities of its dedicated L band satellite and consistent with the provisions outlined in its FCC license.

David Castiel

1990-01-01

165

78 FR 9915 - Radio Broadcasting Services; AM or FM Proposals To Change the Community of License  

Federal Register 2010, 2011, 2012, 2013

...From GOSHEN, AL, To BRANTLEY, AL; AZALEA RADIO CORPORATION, Station NEW, Facility ID 183371, BMPH- 20121206ACO, From ROUNDUP, MT, To LEWISTOWN HEIGHTS, MT; COLONIAL RADIO GROUP, INC. Station WBYB, Facility ID 4586, BPH-20130104ACK,...

2013-02-12

166

Working it out together: Radio policy from Hoover to the radio act of 1927  

Microsoft Academic Search

A complex pattern of radio regulation emerged during the mid?1920s, one in which a close?knit relationship arose between regulator and regulated. Working together to get radio service to the public were the “regulators”—Herbert Hoover and the Department of Commerce—and the “regulated”— Westinghouse, General Electric (G. E.), the Radio Corporation of America (RCA), and American Telegraph and Telephone (AT&T). Together, these

Louise Benjamin

1998-01-01

167

Radio Ghosts  

E-print Network

We investigate the possibility that patches of old radio plasma (`radio ghosts') of former radio galaxies form a second distinct phase of the inter-galactic medium (IGM), not mixed with the thermal gas. The separation of this phase from the ambient gas and its resistance against eroding turbulent forces is given by magnetic fields, which are expected to be roughly in pressure equilibrium with the surrounding medium. Since patches of this plasma are largely invisible in the radio we use the term `radio ghost' to characterize their nature. Possibilities and difficulties of different detection strategies of ghosts are discussed. These involve radio emission, cosmic microwave background (CMB) and starlight Comptonization, and Faraday rotation. Re-activation of the electron population in shock waves of cosmological structure formation, which seems to lead to the cluster radio relic phenomena. We discuss the role radio ghosts can have: They are able to store relativistic particles for cosmological times, but are also able to release them under the influence of very strong turbulence. This might happen during a major merger event of clusters of galaxies. The released relativistic proton population could produce the observed radio halos of some cluster of galaxies via hadronic reactions with the background gas leading to the production of secondary electrons and positrons. Destroyed ghosts, mixed with the IGM can help to magnetize it. Finally, the strong field strength within ghosts should have a significant impact on the propagation of extragalactic high energy cosmic rays.

Torsten A. Ensslin

1999-06-11

168

Digital radio takes to the road  

Microsoft Academic Search

While the transition of television to a digital technology with its improved picture and sound quality has been a much publicized and controversial process, radio, has stayed in the background. But in 2001, in the United States, radio broadcasting is making its own digital leap. Two start-ups are introducing a new type of radio broadcast-subscription-based digital audio sent from satellites.

D. H. Layer

2001-01-01

169

Astronomy research at the Aerospace Corporation. [research projects - NASA programs  

NASA Technical Reports Server (NTRS)

This report reviews the astronomy research carried out at The Aerospace Corporation during 1974. The report describes the activities of the San Fernando Observatory, the research in millimeter wave radio astronomy as well as the space astronomy research.

Paulikas, G. A.

1974-01-01

170

Corporal punishment.  

PubMed

Corporal punishment is used for discipline in most homes in the United States. It is also associated with a long list of adverse developmental, behavioral, and health-related consequences. Primary care providers, as trusted sources for parenting information, have an opportunity to engage parents in discussions about discipline as early as infancy. These discussions should focus on building parents' skills in the use of other behavioral techniques, limiting (or eliminating) the use of corporal punishment and identifying additional resources as needed. PMID:25242709

Zolotor, Adam J

2014-10-01

171

Military applications for Digital Audio Radio Service (DARS)  

Microsoft Academic Search

This paper will discuss the three commercial Digital Audio Radio Service (DARS) systems that are currently, or soon to be, available, and the potential military applications of the different systems. XM Satellite Radio Inc., Sirius Satellite Inc., WorldSpace Corp, and potential future systems from Mobile Broadcasting Corp. and the European Space Agency system are DARS systems that each will provide

A. Hale; D. Ballinger

2002-01-01

172

TV via satellite from AT&T  

NASA Astrophysics Data System (ADS)

AT&T's Satellite Television Service, which relays TV feeds by means of the Comstar domestic communications satellite system, is discussed. Advantages include the ability to provide multiple feeds of program and advertising material simultaneously to affiliates, which can help accommodate the trend toward greater program diversity, and the ability to distribute one signal to many points, making their use economically attractive. A proposed radio service from AT&T is also discussed, which could provide radio broadcasters and programmers with a high-quality, versatile means of transmitting radio programs via satellite.

Kiely, J.

1982-04-01

173

The Bubbler and Radio Scintillation  

NSDL National Science Digital Library

This is a lesson about the formation of plasma bubbles in Earth's ionosphere. Plasma bubbles cause stars to twinkle and radio signals from satellites to distort. Learners will build a model ionosphere in order to demonstrate and understand this process. This activity requires special materials including a laser pointer and silicon-based glue.

174

47 CFR 80.1185 - Supplemental eligibility for mobile-satellite stations.  

Code of Federal Regulations, 2010 CFR

... false Supplemental eligibility for mobile-satellite stations. 80.1185 ...SERVICES Voluntary Radio Installations Mobile-Satellite Stations § 80.1185 Supplemental eligibility for mobile-satellite stations. Stations...

2010-10-01

175

Mobile satellite regulation in the United States  

Microsoft Academic Search

During the last decade, the U.S. FCC has developed the regulatory structure for the provision of mobile services via satellite. In May 1989, the FCC awarded American Mobile Satellite Corporation (AMSC) a license to provide the full range of domestic mobile satellite services in the U.S. At that time, the FCC reaffirmed the U.S. mobile satellite industry structure and spectrum

Lon C. Levin; Walter H. Sonnenfeldt

1990-01-01

176

Radio Telescopes  

NASA Astrophysics Data System (ADS)

``Radio Telescopes" starts with a brief historical introduction from Jansky's1931 discovery of radio emission from the Milky Way through the development ofradio telescope dishes and arrays to aperture synthesis imaging. It includessufficient basics of electromagnetic radiation to provide some understanding of thedesign and operation of radio telescopes. The criteria such as frequencyrange, sensitivity, survey speed, angular resolution, and field of view thatdetermine the design of radio telescopes are introduced. Because it is soeasy to manipulate the electromagnetic waves at radio frequencies, radiotelescopes have evolved into many different forms, sometimes with "wire"structures tuned to specific wavelengths, which look very different from anykind of classical telescope. To assist astronomers more familiar with otherwavelength domains, the appendix A.1. includes a comparison of radioand optical terminology. Some of the different types of radio telescopesincluding the filled aperture dishes, electronically steered phased arrays, andaperture synthesis radio telescopes are discussed, and there is a sectioncomparing the differences between dishes and arrays. Some of the morerecent developments including hierarchical beam forming, phased arrayfeeds, mosaicing, rotation measure synthesis, digital receivers, and longbaseline interferometers are included. The problem of increasing radiofrequency interference is discussed, and some possible mitigation strategies areoutlined.

Ekers, Ron; Wilson, Thomas L.

177

Corporation for Public Broadcasting: Mission and Goals, Tasks and Responsibilities.  

ERIC Educational Resources Information Center

This brochure contains two statements adopted by the Corporation for Public Broadcasting (CPB), one outlining the Corporation's mission and goals, and the other outlining its tasks and responsibilities. The mission of the CPB is to take the lead in developing a uniquely American non-commercial public radio and television system that will inform,…

Corporation for Public Broadcasting, Washington, DC.

178

Corporate strategy and the Social Networking phenomena  

Microsoft Academic Search

The Social Networking (SN) phenomena has developed relatively overnight and is continuing to develop at an exponential pace. It allows for innovative new methods of disseminating and collecting information in ways never before dreamed possible by corporate executives. The rise of Social Networking is becoming a disruptive technology for traditional marketing and advertising medium such as radio, television, web page,

Robert L. Johnson

2010-01-01

179

Why Radio?  

ERIC Educational Resources Information Center

Addresses such broad issues as the function of public radio in contemporary American culture, and how its public service justifies the public money it now receives, or any increased amounts it might receive in the future. (Author/CMV)

Josephson, Larry

1979-01-01

180

CB Radios  

ERIC Educational Resources Information Center

Citizen band radios keep trucking across the American scene, and no doubt your students are caught in the folk craze. Provides some suggestions for channeling students' interests with a unit on CBs. (Author/RK)

Martin, Dick

1977-01-01

181

The perspective of satellite television development in Russia  

Microsoft Academic Search

The concept of satellite TV and radio broadcasting development in Russia is being currently worked out by the Russian Federal Television and Radio Service. The work is being carried out with allowance made for the state budget and market economy mechanism. It is vital for the Russian Satellite Television System to be based, mainly, on local budgets and regional market

A. G. Kozlov; A. N. Belobrov; D. V. Kozlov; V. P. Radaykin

1994-01-01

182

A Satellite Study of VLF HISS.  

National Technical Information Service (NTIS)

Broad-band VLF radio noises from about 4 kc/s to above 10 kc/s are frequently observed near the auroral zone with the Injun 3 satellite. These broad-band VLF radio noises are called VLF hiss. In this study we select VLF hiss events for analysis by requiri...

D. A. Gurnett

1966-01-01

183

Digital audio for satellite network radio  

Microsoft Academic Search

The paper presents the time-division-multiplexed (TDM) digital system supplied by Scientific-Atlanta for ABC, CBS, and NBC. The system has a transmission rate of 8.78 Mbps, and can demodulate, decode and demultiplex the data into the desired audio and data channels, supporting data rates equivalent to twenty 15 kHz audio channels at 384 kbps each. Digital transmission is used for data

A. L. McBride

1982-01-01

184

Space radio services and WARC-MOB-87  

Microsoft Academic Search

A recent conference of the ITU has agreed upon worldwide frequency allocations near 1600 MHz for communication by satellite with mobile stations on land, and has permitted the use of some aeronautical mobile-satellite frequency bands for passengers' in-flight telephone calls to the ground. Frequencies for systems for locating mobile stations by radio, using satellites, were allocated.

D. J. Withers

1988-01-01

185

Geron Corporation  

NSDL National Science Digital Library

Geron Corporation is a biopharmaceutical company specializing in therapeutic and diagnostic products for age-related diseases. Geron owns several telomerase related patents. Calvin B. Harley of Geron is one of the co-authors of the Science article. Their page describes programs and products related to cellular aging and Cancer Therapeutics. There has been a recent finding regarding telomerase, a gene which affects the mechanisms controlling human cell replication. The site above provides general information on telomerase, current telomere research, and the use of telemorase in medical practice. Telomerase increases the life-span of a cell, and is thus central to both aging and cancer.

1998-01-01

186

Correlation between X-ray Lightcurve Shape and Radio Arrival Time in the Vela Pulsar  

E-print Network

-rays and radio from the RXTE satellite and the Mount Pleasant Radio Observatory in Tasmania. We sought, Madrid, Espa~na 8 University of Tasmania, Tasmania, Australia. 9 Furman University, Greenville, South

Gwinn, Carl

187

Mobile satellite regulation in the United States  

NASA Astrophysics Data System (ADS)

During the last decade, the U.S. FCC has developed the regulatory structure for the provision of mobile services via satellite. In May 1989, the FCC awarded American Mobile Satellite Corporation (AMSC) a license to provide the full range of domestic mobile satellite services in the U.S. At that time, the FCC reaffirmed the U.S. mobile satellite industry structure and spectrum allocations that had been adopted previously. Also in May 1989, the FCC authorized the Communications Satellite Corporation (COMSAT), the U.S. Signatory to Inmarsat, to provide international aeronautical satellite service via the Inmarsat system. Earlier in 1989, the FCC permitted the use of Ku-band satellites to provide messaging and tracking services. In the mid-1980's, the FCC established the Radiodetermination Satellite Service and awarded licenses. Among the mobile satellite matters currently facing the FCC are whether additional spectrum should be allocated for domestic 'generic' mobile satellite services, the regulatory structure for the provision of mobile satellite service on an interim basis before AMSC launches its dedicated satellites, and whether to authorize a low earth orbit satellite system to provide mobile data service.

Levin, Lon C.; Sonnenfeldt, Walter H.

188

Mobile satellite regulation in the United States  

NASA Technical Reports Server (NTRS)

During the last decade, the U.S. FCC has developed the regulatory structure for the provision of mobile services via satellite. In May 1989, the FCC awarded American Mobile Satellite Corporation (AMSC) a license to provide the full range of domestic mobile satellite services in the U.S. At that time, the FCC reaffirmed the U.S. mobile satellite industry structure and spectrum allocations that had been adopted previously. Also in May 1989, the FCC authorized the Communications Satellite Corporation (COMSAT), the U.S. Signatory to Inmarsat, to provide international aeronautical satellite service via the Inmarsat system. Earlier in 1989, the FCC permitted the use of Ku-band satellites to provide messaging and tracking services. In the mid-1980's, the FCC established the Radiodetermination Satellite Service and awarded licenses. Among the mobile satellite matters currently facing the FCC are whether additional spectrum should be allocated for domestic 'generic' mobile satellite services, the regulatory structure for the provision of mobile satellite service on an interim basis before AMSC launches its dedicated satellites, and whether to authorize a low earth orbit satellite system to provide mobile data service.

Levin, Lon C.; Sonnenfeldt, Walter H.

1990-01-01

189

Public Radio/Television Survey; Report 4: Methodology.  

ERIC Educational Resources Information Center

The last in a series of four, this report describes part of a national study commissioned by the Corporation for Public Broadcasting to investigate audience awareness of public radio, reaction to on-air fund raising and programing on public radio, and audience reactions to on-air fund raising by public television stations. Discussion centers on…

Corporation for Public Broadcasting, Washington, DC.

190

Public Radio Programming Content by Category, Fiscal Year 1982.  

ERIC Educational Resources Information Center

Part of a series of statistical surveys on public broadcasting based on data supplied by public television and Corporation for Public Broadcasting qualified public radio stations, this report provides details of public radio program content for fiscal year 1982. The chapters include information on the following: (1) definitions and categories; (2)…

Mendel, Robin; And Others

191

Near Term Digital Radio-a first look  

Microsoft Academic Search

An ITT Industries led team is developing the Near Term Digital Radio (NTDR) Information Transport System (ITS) for PM Tactical Radio Communication Systems to meet the growing need for higher capacity digital information distribution on a highly mobile battlefield. The team consists of Motorola, Lockheed Sanders, BBN, SICOM and Group Technology Corporation. The NTDR ITS is based on open architecture

L. Williams; L. Emergy

1996-01-01

192

Radio astronomy  

NASA Technical Reports Server (NTRS)

The following subject areas are covered: (1) scientific opportunities (millimeter and sub-millimeter wavelength astronomy; meter to hectometer astronomy; the Sun, stars, pulsars, interstellar masers, and extrasolar planets; the planets, asteroids, and comets; radio galaxies, quasars, and cosmology; and challenges for radio astronomy in the 1990's); (2) recommendations for new facilities (the millimeter arrays, medium scale instruments, and small-scale projects); (3) continuing activities and maintenance, upgrading of telescopes and instrumentation; (4) long range programs and technology development; and (5) social, political, and organizational considerations.

Kellermann, Kenneth I.; Heeschen, David; Backer, Donald C.; Cohen, Marshall H.; Davis, Michael; Depater, Imke; Deyoung, David; Dulk, George A.; Fisher, J. R.; Goss, W. Miller

1991-01-01

193

The Cooperative Satellite Learning Project.  

ERIC Educational Resources Information Center

This document describes the Cooperative Satellite Learning Project (CSLP) which is designed to educate students in the areas of space science, engineering, and technology in a business-like atmosphere. The project is a partnership between the National Aeronautics and Space Association (NASA), Allied Signal Technical Services Corporation, and…

Caler, Michelle

194

Use of communications. [satellite communication  

NASA Technical Reports Server (NTRS)

Progress in the field of satellite communications is reviewed, and useful services which may be provided by future satellite communications systems are considered. Recommendations are made with regard to mobile communications for use on land and at sea, position determination, mineral and energy exploration, the possibility of using electronic means to assist in main delivery, education and health-care experiments, and the use of satellite telecommunications to enhance the quality of life in rural areas by making available a full range of educational and entertainment programs. The needs of the amateur radio community are also considered.

1975-01-01

195

25 years of satellite beacon studies - Australia and New Zealand  

NASA Astrophysics Data System (ADS)

An evaluation is made of the Australian and New Zealand contributions to satellite radio beacon studies over the last 25 years. Early work was based on the signals of the Sputnik 1 and 3 satellites, and then on those of the Explorer satellites. The availability of geostationary satellites after 1965 offered an opportunity for continuous monitoring of the ionosphere, and the most recent efforts are predicated on the system of six NNSS satellites, which facilitates expanded spatial and temporal coverage of the ionosphere.

Cohen, E. A.

196

Antecedents of corporate volunteerism  

E-print Network

of organizations are leading to a growing interest in corporate social responsibility among management and researchers. One method to achieving greater corporate social responsibility is corporate-sponsored volunteering. Many benefits have been associated...

Henning, Jaime Blaine

2009-05-15

197

VLBI Observations of Geostationary Satellites  

NASA Astrophysics Data System (ADS)

For a consistent realization of a Global Geodetic Observing System (GGOS), a proper tie between the individual global reference systems used in the analysis of space-geodetic observations is a prerequisite. For instance, the link between the terrestrial, the celestial and the dynamic reference system of artificial Earth orbiters may be realized by Very Long O Baseline Interferometry (VLBI) observations of one or several satellites. In the preparation phase for a dedicated satellite mission, one option to realize this is using a geostationary (GEO) satellite emitting a radio signal in X-Band and/or S-Band and, thus, imitating a quasar. In this way, the GEO satellite can be observed by VLBI together with nearby quasars and the GEO orbit can, thus, be determined in a celestial reference frame. If the GEO satellite is, e.g., also equipped with a GNSS-type transmitter, a further tie between GNSS and VLBI may be realized. In this paper, a concept for the generation of a radio signal is shown. Furthermore, simulation studies for estimating the GEO position are presented with a GEO satellite included in the VLBI schedule. VLBI group delay observations are then simulated for the quasars as well as for the GEO satellite. The analysis of the simulated observations shows that constant orbit changes are adequately absorbed by estimated orbit parameters. Furthermore, the post-fit residuals are comparable to those from real VLBI sessions.

Artz, T.; Nothnagel, A.; La Porta, L.

2013-08-01

198

Theories of Corporate Groups: Corporate Identity Reconceived  

E-print Network

Theoretical debates about the nature of the corporation have raged for over a century, with competing visions of the corporation holding sway in different regulatory arenas and each making claims for normative supremacy. ...

Harper Ho, Virginia E.

2012-06-17

199

A Study of Public Radio Stations' Educational Services, 1978-79.  

ERIC Educational Resources Information Center

This second national survey of public radio stations' involvement in educational services to schools, colleges, and universities was conducted by the Corporation for Public Broadcasting (CPB) for use by individual public radio stations, educational agencies, and other organizations interested and involved in planning public radio's services to…

Corporation for Public Broadcasting, Washington, DC.

200

Design of the American Mobile Satellite System  

NASA Technical Reports Server (NTRS)

This paper presents an overview of the American Mobile Satellite Corporation (AMSC) Mobile Satellite System (MSS). A summary of the mobile satellite (MSAT) design and overall performance is provided. The design and components of both the forward link and return link transponders are described in detail. The design and operation of a unique hybrid matrix amplifier that offers flexible power distribution is outlined. The conceptual design and performance of three types of land mobile antennas are described.

Kittiver, Charles

1991-01-01

201

Description of the AMSC mobile satellite system  

NASA Astrophysics Data System (ADS)

The American Mobile Satellite Corporation will provide a full range of mobile satellite services through a mobile satellite system dedicated to mobile use in the United States. This paper provides a summary of the system architecture with descriptions of each of the major system elements. The elements are the space segment, network control system, mobile earth terminals and feeder-link earth stations. The general transmission plan is also described.

Garner, W. B.

202

Design of the American Mobile Satellite System  

NASA Astrophysics Data System (ADS)

This paper presents an overview of the American Mobile Satellite Corporation (AMSC) Mobile Satellite System (MSS). A summary of the mobile satellite (MSAT) design and overall performance is provided. The design and components of both the forward link and return link transponders are described in detail. The design and operation of a unique hybrid matrix amplifier that offers flexible power distribution is outlined. The conceptual design and performance of three types of land mobile antennas are described.

Kittiver, Charles

1991-09-01

203

Managing Corporate Image and Corporate Reputation  

Microsoft Academic Search

The concepts of corporate reputation and corporate identity represent a relatively new and supplemental lens through which top management can address the strategic issues facing their firm. To help guide the thinking of senior executives in managing their organization’s reputation and image, the authors present a pragmatic operational model. The model shows that in addition to an understanding of corporate

Edmund R. Gray; John M. T. Balmer

1998-01-01

204

How Satellite Observations Impact NWP  

NSDL National Science Digital Library

Satellite observations have a huge impact on numerical weather prediction (NWP) model analyses and forecasts, with sounding data from polar orbiting and GPS-radio occultation satellites reducing model forecast error by almost half. All of this despite the fact that NWP models only assimilate 5% of all satellite observations! This lesson discusses the use of satellite observations in NWP and how model limitations prevent more of the data from being assimilated. The lesson begins by briefly describing the history of satellite observations in NWP and their impact on NWP model forecast skill. The next part provides background information about the types of environmental satellites that provide input to NWP, the satellite observations that are assimilated, the major components of NWP models, and how they forecast atmospheric behavior. This sets the stage for the main part of the lesson, which examines how observations from new satellite instruments are vetted for inclusion in data assimilation systems and how observations deemed acceptable are actually assimilated. The final part describes current challenges to making optimal use of satellite observations in NWP and advances that are expected to address these challenges and improve model forecasts.

Comet

2014-03-12

205

Identification of Spaceborne Microwave Radiometer Calibration Sites for Satellite Missions  

Microsoft Academic Search

The first dedicated soil moisture satellite mission will be the European Space Agency's Soil Moisture and Ocean Salinity (SMOS) mission. This satellite, scheduled for launch in the second half of 2009, has a new type of satellite design that is based on the radio-astronomy technique of simulating a large antenna from a number of smaller ones placed some distance apart.

C. Rüdiger; J. P. Walker; D. Barrett; J. Costelloe

2009-01-01

206

STEED: Satellite Threat Evaluation Environment for Defensive Counterspace  

Microsoft Academic Search

The design knowledge company (TDKC) is currently developing a defensive counterspace intelligence tool for the air force research laboratory (AFRL) called the satellite threat evaluation environment for defensive counterspace (STEED). STEED provides analysis collaboration and situational awareness features for satellite systems operators. STEED incorporates a wide variety of data sources, including satellite as a sensor (SAS), space weather, proximity, radio

E. Loomis

2007-01-01

207

Pre-Flight Testing and Performance of a Ka-Band Software Defined Radio  

NASA Technical Reports Server (NTRS)

National Aeronautics and Space Administration (NASA) has developed a space-qualified, reprogrammable, Ka-band Software Defined Radio (SDR) to be utilized as part of an on-orbit, reconfigurable testbed. The testbed will operate on the truss of the International Space Station beginning in late 2012. Three unique SDRs comprise the testbed, and each radio is compliant to the Space Telecommunications Radio System (STRS) Architecture Standard. The testbed provides NASA, industry, other Government agencies, and academic partners the opportunity to develop communications, navigation, and networking applications in the laboratory and space environment, while at the same time advancing SDR technology, reducing risk, and enabling future mission capability. Designed and built by Harris Corporation, the Ka-band SDR is NASA's first space-qualified Ka-band SDR transceiver. The Harris SDR will also mark the first NASA user of the Ka-band capabilities of the Tracking Data and Relay Satellite System (TDRSS) for on-orbit operations. This paper describes the testbed's Ka-band System, including the SDR, travelling wave tube amplifier (TWTA), and antenna system. The reconfigurable aspects of the system enabled by SDR technology are discussed and the Ka-band system performance is presented as measured during extensive pre-flight testing.

Downey, Joseph A.; Reinhart, Richard C.; Kacpura, Thomas

2012-01-01

208

The Radio JOVE Project - Shoestring Radio Astronomy  

NASA Technical Reports Server (NTRS)

Radio JOVE is an education and outreach project intended to give students and other interested individuals hands-on experience in learning radio astronomy. They can do this through building a radio telescope from a relatively inexpensive kit that includes the parts for a receiver and an antenna as well as software for a computer chart recorder emulator (Radio Skypipe) and other reference materials

Thieman, J.; Flagg, R.; Greenman, W.; Higgins, C.; Reyes, F.; Sky, J.

2010-01-01

209

Analysis and Modeling of Jovian Radio Emissions Observed by Galileo  

NASA Technical Reports Server (NTRS)

Our studies of Jovian radio emission have resulted in the publication of five papers in refereed journals, with three additional papers in progress. The topics of these papers include the study of narrow-band kilometric radio emission; the apparent control of radio emission by Callisto; quasi-periodic radio emission; hectometric attenuation lanes and their relationship to Io volcanic activity; and modeling of HOM attenuation lanes using ray tracing. A further study of the control of radio emission by Jovian satellites is currently in progress. Abstracts of each of these papers are contained in the Appendix. A list of the publication titles are also included.

Menietti, J. D.

2003-01-01

210

Space Telecommunications Radio System STRS Cognitive Radio  

NASA Technical Reports Server (NTRS)

Radios today are evolving from awareness toward cognition. A software defined radio (SDR) provides the most capability for integrating autonomic decision making ability and allows the incremental evolution toward a cognitive radio. This cognitive radio technology will impact NASA space communications in areas such as spectrum utilization, interoperability, network operations, and radio resource management over a wide range of operating conditions. NASAs cognitive radio will build upon the infrastructure being developed by Space Telecommunication Radio System (STRS) SDR technology. This paper explores the feasibility of inserting cognitive capabilities in the NASA STRS architecture and the interfaces between the cognitive engine and the STRS radio. The STRS architecture defines methods that can inform the cognitive engine about the radio environment so that the cognitive engine can learn autonomously from experience, and take appropriate actions to adapt the radio operating characteristics and optimize performance.

Briones, Janette C.; Handler, Louis M.

2013-01-01

211

Information and Corporate Cultures.  

ERIC Educational Resources Information Center

This paper defines "corporate culture" (set of values and beliefs shared by people working in an organization which represents employees' collective judgments about future) and discusses importance of corporate culture, nature of corporate cultures in business and academia, and role of information in shaping present and future corporate cultures.…

Drake, Miriam A.

1984-01-01

212

Corporate Philanthropy and Libraries  

Microsoft Academic Search

This article discusses the history of corporate philanthropy in the United States. It traces the response of corporations to cutbacks in federal spending initiated by President Ronald Reagan. The author concludes that libraries must learn to approach private corporations for in-kind donations, product donations, and volunteer help, as well as grant funds. Because corporations benefit through publicity, name recognition, and

Maribelle Davis

1985-01-01

213

LDEF Satellite Radiation Analyses  

NASA Technical Reports Server (NTRS)

This report covers work performed by Science Applications International Corporation (SAIC) under contract NAS8-39386 from the NASA Marshall Space Flight Center entitled LDEF Satellite Radiation Analyses. The basic objective of the study was to evaluate the accuracy of present models and computational methods for defining the ionizing radiation environment for spacecraft in Low Earth Orbit (LEO) by making comparisons with radiation measurements made on the Long Duration Exposure Facility (LDEF) satellite, which was recovered after almost six years in space. The emphasis of the work here is on predictions and comparisons with LDEF measurements of induced radioactivity and Linear Energy Transfer (LET) measurements. These model/data comparisons have been used to evaluate the accuracy of current models for predicting the flux and directionality of trapped protons for LEO missions.

Armstrong, T. W.; Colborn, B. L.

1996-01-01

214

Radio Variability of Radio Quiet and Radio Loud Quasars  

E-print Network

The majority of quasars are weak in their radio emission, with flux densities comparable to those in the optical, and energies far lower. A small fraction, about 10%, are hundreds to thousands of times stronger in the radio. Conventional wisdom holds that there are two classes of quasars, the radio quiets and radio louds, with a deficit of sources having intermediate power. Are there really two separate populations, and if so, is the physics of the radio emission fundamentally different between them? This paper addresses the second question, through a study of radio variability across the full range of radio power, from quiet to loud. The basic findings are that the root mean square amplitude of variability is independent of radio luminosity or radio-to-optical flux density ratio, and that fractionally large variations can occur on timescales of months or less in both radio quiet and radio loud quasars. Combining this with similarities in other indicators, such as radio spectral index and the presence of VLBI-scale components, leads to the suggestion that the physics of radio emission in the inner regions of all quasars is essentially the same, involving a compact, partially opaque core together with a beamed jet.

Richard Barvainis; Joseph Lehar; Mark Birkinshaw; Heino Falke; Katherine M. Blundell

2004-09-22

215

Radio and Plasma Waves Synergistic Science Opportunities with EJSM  

Microsoft Academic Search

The radio and plasma wave (RPW) diagnostics provide a unique access to critical parameters of space plasma, in particular in planetary and satellite environments. Concerning giant planets, this has been demonstrated by major results obtained by the radio investigation on the Galileo and Cassini spacecraft, but also during the Ulysses, Voyager, and Pioneer flybys of Jupiter. Several other missions, past

Baptiste Cecconi; Nicolas André; Jean-Louis Bougeret

2010-01-01

216

Higher order ionospheric propagation effects on GPS radio occultation signals  

Microsoft Academic Search

With the increasing number of remote sensing satellites using the GPS radio occultation technique for atmospheric sounding, the estimation of higher order ionospheric effects and their mitigation have become relevant and important. Due to long ionospheric limb paths, GPS signals are strongly affected by ionospheric refraction during radio occultation. Standard dual-frequency GPS measurements may be used to estimate the first

M. Mainul Hoque; N. Jakowski

2010-01-01

217

Canadian Broadcasting Corporation Archives: Science and Technology  

NSDL National Science Digital Library

This collection of radio and television clips from the archives of the Canadian Broadcasting Corporation (CBC) lets users explore the scientific and medical inventions, discoveries, and developments that have shaped Canada's history. The clips are organized by topic, including climate change, medical research, natural disasters, technology, pollution, and many others. There is also a collection of "On this Day" clips celebrating the anniversaries of important scientific and technological events in Canada.

218

Satellite telemetry  

NASA Astrophysics Data System (ADS)

Hydrologic application of satellite data collection systems in Brazil is discussed. The Data Collection Platform (DCP) is a telemetry station used for the acquisition of environmental parameters. Artificial satellites are employed to relay the data to receiving centers. Two meteorologic satellite data collection systems are in operation in Brazil: the ARGOS system, on board low-orbit (850 km) satellites of the TIROS-NOAA series, and the Geostationary Operational Satellite (GOES) system, on board geostationary satellites (36,000 km) of the SMS/GOES series. DCPs have been used mainly in the field of hydrology to obtain timely data, to make decisions, and to compose historical records. The first DCP network established in Brazil was in the Tocantins Basin, which has 10 telemetry stations. Other networks are currently being planned. Prototypes of ARGOS and GOES DCPs are being developed that are aimed at further industrialization and improved supply of national demand.

Deolveira, J. R.

1983-08-01

219

RF Voltmeters Models 91B, 91C, 91CA, 91D (Boonton Electronics Corporation).  

National Technical Information Service (NTIS)

The procedure describes the calibration of the Boonton Electronics Corporation 91B, 91C, 91CA, and 91D R-F Voltmeters, which are capable of measuring radio frequency voltages over a wide frequency range.

1966-01-01

220

Radio Jove: Jupiter Radio Astronomy for Citizens  

NASA Astrophysics Data System (ADS)

Radio JOVE is a hands-on educational activity that brings the radio sounds of the Sun, Jupiter, the Milky Way Galaxy, and terrestrial radio noise to students, teachers, and the general public. Participants may build a simple radio telescope kit, make scientific observations, and interact with professional radio observatories in real-time over the Internet. Our website (http://radiojove.gsfc.nasa.gov) includes science information, construction manuals, observing guides, and education resources for teachers and students. Radio Jove is continually expanding its participants with over 1800 kits sold to more than 70 countries worldwide. Recently some of our most dedicated observers have upgraded their Radio Jove antennas to semi-professional observatories. We have spectrographs and wide band antennas, some with 8 MHz bandwidth and some with dual polarization capabilities. In an effort to add to the science literature, these observers are coordinating their efforts to pursue some basic questions about Jupiter’s radio emissions (radio source locations, spectral structure, long term changes, etc.). We can compare signal and ionosphere variations using the many Radio Jove observers at different locations. Observers are also working with members of the Long Wavelength Array Station 1 (LWA1) radio telescope to coordinate observations of Jupiter; Radio Jove is planning to make coordinated observations while the Juno Mission is active beginning in 2015. The Radio Jove program is overviewed, its hardware and software are highlighted, recent sample observations are shown, and we demonstrate that we are capable of real citizen science.

Higgins, Charles; Thieman, J. R.; Flagg, R.; Reyes, F. J.; Sky, J.; Greenman, W.; Brown, J.; Typinski, D.; Ashcraft, T.; Mount, A.

2014-01-01

221

Artificial Satellites  

NSDL National Science Digital Library

Over 2,000 man-made satellites are currently orbiting the Earth, providing a wide range of services like communications, remote sensing, and global positioning. As more are launched and new technologies are developed, they will play an increasingly important role in everyday life.The Tech Museum offers this site (1) dedicated to the basics of satellites and their functions. A Java program complements the Satellite Anatomy section, which illustrates the standard components of three different categories of satellites. More information specific to satellite launches and their orbits can be found here (2). Most of the material is composed of fun experiments that demonstrate satellite operation. One of the most interesting features on this NASA site (3) is the Live 3D Java Tracking Display, which shows hundreds of different satellites and their current position in orbit. A few selected news articles and a separate section on satellite applications are also provided. The European Space Agency provides a look at solar power satellites (4), which could essentially "beam" energy to Earth. While it is not a new concept, the sheer magnitude of a project to construct a solar power satellite has thus far been too great to justify an attempt. At a conference held in December 2002 (5), representatives from the satellite industry convened to discuss current developments. Although many of the articles only address industry outlooks, some are more technology-oriented. For instance, one considers a new navigation system that could improve overall coverage and signal availability. A lesson plan (6) for grades K-5 teaches children how satellites are launched and some basic terminology. The activity uses different sized marbles, clay, and some other items to demonstrate fundamental concepts. Satellites of the Global Positioning System are being used for more than they were originally intended in England. This news article (7) describes how they are used to study earthquakes and corresponding movements in the Earth's crust. In other news (8), the largest communications satellite ever built was lost in November 2002. The failure of one of its launching rockets resulted in the satellite falling in a decaying orbit until it fell into the sea.

Leske, Cavin.

2003-01-01

222

Plasma interactions of exoplanets with their parent star and associated radio emissions  

Microsoft Academic Search

The relatively high contrast between planetary and solar low-frequency radio emissions suggests that the low-frequency radio range may be well adapted to the direct detection of exoplanets. We review the most significant properties of planetary radio emissions (auroral as well as satellite induced) and show that their primary engine is the interaction of a plasma flow with an obstacle in

Philippe Zarka

2007-01-01

223

Satellite Tracker  

NSDL National Science Digital Library

Students use satellite tracking software available on the Internet to monitor a very large satellite, the International Space Station. Using information from this online resource, students predict and graph the motion of the space station at their location and create a 3-D display of its path through the sky.

Integrated Teaching And Learning Program

224

Soaring Satellites  

NSDL National Science Digital Library

Working in small teams, learners try to build a satellite that can float for at least five seconds in the marked area of a vertical wind tube. Learners think about and explore the concepts of lift and weight as they try to adapt their satellite to hover between the lines.

Museum Of Science, Boston

2010-01-01

225

A compact car antenna with high efficiency for reception of HEO- and GEO-satellite signals  

Microsoft Academic Search

For Satellite Digital Audio Radio Services (SDARS) a new satellite antenna is presented which shows a high efficiency and a large bandwidth in comparison to conventional SDARS receiving antennas as for example patch antennas. The antenna requires only a small mounting volume and shows a radiation pattern which is tailored to the reception of satellite signals transmitted via highly-elliptical-orbit satellites

Johannes Kammerer; Stefan Lindenmeier

2011-01-01

226

Controlling satellite communication system unwanted emissions in congested RF spectrum  

NASA Astrophysics Data System (ADS)

The International Telecommunication Union (ITU), a United Nations (UN) agency, is the agency that, under an international treaty, sets radio spectrum usage regulations among member nations. Within the United States of America (USA), the organization that sets regulations, coordinates an application for use, and provides authorization for federal government/agency use of the radio frequency (RF) spectrum is the National Telecommunications and Information Administration (NTIA). In this regard, the NTIA defines which RF spectrum is available for federal government use in the USA, and how it is to be used. The NTIA is a component of the United States (U.S.) Department of Commerce of the federal government. The significance of ITU regulations is that ITU approval is required for U.S. federal government/agency permission to use the RF spectrum outside of U.S. boundaries. All member nations have signed a treaty to do so. U.S. federal regulations for federal use of the RF spectrum are found in the Manual of Regulations and Procedures for Federal Radio Frequency Management, and extracts of the manual are found in what is known as the Table of Frequency Allocations. Nonfederal government and private sector use of the RF spectrum within the U.S. is regulated by the Federal Communications Commission (FCC). There is a need to control "unwanted emissions" (defined to include out-of-band emissions, which are those immediately adjacent to the necessary and allocated bandwidth, plus spurious emissions) to preclude interference to all other authorized users. This paper discusses the causes, effects, and mitigation of unwanted RF emissions to systems in adjacent spectra. Digital modulations are widely used in today's satellite communications. Commercial communications sector standards are covered for the most part worldwide by Digital Video Broadcast - Satellite (DVB-S) and digital satellite news gathering (DSNG) evolutions and the second generation of DVB-S (DVB-S2) standard, developed by the European Telecommunications Standards Institute (ETSI). In the USA, the Advanced Television Systems Committee (ATSC) has adopted Europe's DVB-S and DVB-S2 standards for satellite digital transmission. With today's digital modulations, RF spectral side lobes can extend out many times the modulating frequency on either side of the carrier at excessive power levels unless filtered. Higher-order digital modulations include quadrature phase shift keying (QPSK), 8 PSK (8-ary phase shift keying), 16 APSK (also called 12-4 APSK (amplitude phase shift keying)), and 16 QAM (quadrature amplitude modulation); they are key for higher spectrum efficiency to enable higher data rate transmissions in limited available bandwidths. Nonlinear high-power amplifiers (HPAs) can regenerate frequency spectral side lobes on input-filtered digital modulations. The paper discusses technologies and techniques for controlling these spectral side lobes, such as the use of square root raised cosine (SRRC) filtering before or during the modulation process, HPA output power back-off (OPBO), and RF filters after the HPA. Spectral mask specifications are a common method of the NTIA and ITU to define spectral occupancy power limits. They are intended to reduce interference among RF spectrum users by limiting excessive radiation at frequencies beyond the regulatory allocated bandwidth.The focus here is on the communication systems of U.S. government satellites used for space research, space operations, Earth exploration satellite services (EESS), meteorological satellite services (METSATS), and other government services. The 8025 to 8400 megahertz (MHz) X band can be used to illustrate the "unwanted emissions" issue. 8025 to 8400 MHz abuts the 8400 to 8450 MHz band allocated by the NTIA and ITU to space research for space-to-Earth transmissions such as receiving very weak Deep Space Network signals. The views and ideas expressed in this paper are those of the authors and do not necessarily reflect those of The Aerospace Corporation or The National Oceanic and Atmosphe

Olsen, Donald; Heymann, Roger

2007-09-01

227

An economic systems analysis of land mobile radio telephone services  

Microsoft Academic Search

This paper deals with the economic interaction of the terrestrial and satellite land-mobile radio service systems. The cellular, trunked and satellite land-mobile systems are described. Parametric equations are formulated to allow examination of necessary user thresholds and growth rates as functions of system costs. Conversely, first order allowable systems costs are found as a function of user thresholds and growth

B. E. Leroy; S. M. Stevenson

1980-01-01

228

Observations with the GISMOS Airborne Radio Occultation System  

Microsoft Academic Search

The spatial sample density of temperature and moisture profiles derived from the current spaceborne GPS radio occultation (RO) constellation is limited by the number of occultation satellites in operation. With the current RO satellite configuration, only one RO profile per day is typically available in a 160,000 square kilometer area in the mid-latitude and tropics and slightly more in high

Paytsar Muradyan; Jennifer Haase; James Garrison; Tyler Lulich; Feiqin Xie

2010-01-01

229

Meteorological satellites  

NASA Technical Reports Server (NTRS)

An overview is presented of the meteorological satellite programs that have been evolving from 1958 to the present, and plans for the future meteorological and environmental satellite systems that are scheduled to be placed into service in the early 1980's are reviewed. The development of the TIROS family of weather satellites, including TIROS, ESSA, ITOS/NOAA, and the present TIROS-N (the third generation operational system) is summarized. The contribution of the Nimbus and ATS technology satellites to the development of the operational-orbiting and geostationary satellites is discussed. Included are descriptions of both the TIROS-N and the DMSP payloads currently under development to assure a continued and orderly growth of these systems into the 1980's.

Allison, L. J. (editor); Schnapf, A.; Diesen, B. C., III; Martin, P. S.; Schwalb, A.; Bandeen, W. R.

1980-01-01

230

Corporate sustainability assessment methodology  

E-print Network

Sustainability is a vague concept specifically in the context of a corporate world. There are numerous definitions for corporate sustainability and just as many ways of evaluating it. This work attempts to define, structure ...

Pinchuk, Natallia

2011-01-01

231

47 CFR 76.66 - Satellite broadcast signal carriage.  

Code of Federal Regulations, 2013 CFR

...BROADCAST RADIO SERVICES MULTICHANNEL VIDEO AND CABLE TELEVISION SERVICE Carriage...satellite carrier that offers multichannel video programming distribution service...shall include in its entirety the primary video, accompanying audio, and closed...

2013-10-01

232

47 CFR 76.66 - Satellite broadcast signal carriage.  

Code of Federal Regulations, 2011 CFR

...BROADCAST RADIO SERVICES MULTICHANNEL VIDEO AND CABLE TELEVISION SERVICE Carriage...satellite carrier that offers multichannel video programming distribution service...shall include in its entirety the primary video, accompanying audio, and closed...

2011-10-01

233

47 CFR 76.66 - Satellite broadcast signal carriage.  

Code of Federal Regulations, 2010 CFR

...BROADCAST RADIO SERVICES MULTICHANNEL VIDEO AND CABLE TELEVISION SERVICE Carriage...satellite carrier that offers multichannel video programming distribution service...shall include in its entirety the primary video, accompanying audio, and closed...

2010-10-01

234

47 CFR 76.66 - Satellite broadcast signal carriage.  

Code of Federal Regulations, 2012 CFR

...BROADCAST RADIO SERVICES MULTICHANNEL VIDEO AND CABLE TELEVISION SERVICE Carriage...satellite carrier that offers multichannel video programming distribution service...shall include in its entirety the primary video, accompanying audio, and closed...

2012-10-01

235

Corporate Affiliate Event Details  

E-print Network

and marketing benefits. Extend this highly-regarded educational oppor- tunity throughout your organization Corporation Tampa Bay Lightning Tenneco Inc. TreeHouse Foods, Inc. Attendee Profile 2013 Corporate Counsel a bundle of discounted registrations which can be used by any- one in their organization. Corporate

Shahriar, Selim

236

Corporate Management and Education.  

ERIC Educational Resources Information Center

Corporate management is a reorganization of local government promulgated in Great Britain by the Bains Report and reinforced by the 1974 reorganization act. It emphasizes that the departmental orientation of much of local government must give way to a broader, unifying, corporate perspective. The example of how corporate management has not worked…

Saxe, Richard W.

237

LLM in Corporate Responsibility  

E-print Network

LLM in Corporate Social Responsibility As traditional forms of legal regulation through company law or trade law fail, the concept of corporate social responsibility is becoming increasingly important http://stir.ac.uk/7v #12;Why study for an LLM in Corporate Social Responsibility ? As traditional forms of legal

Little, Tony

238

Scaling the Corporate Heights.  

ERIC Educational Resources Information Center

Reviews "Black Life in Corporate America" (Davis and Watson), "Women at Work: A Psychologist's Secrets to Getting Ahead in Business" (Senter), and "The Black Manager, Making It in the Corporate World" (Dickens and Dickens). All three books address general issues confronting Black/female managers, and two offer guidance to corporate newcomers. (CMG)

Campbell, Bebe Moore

1983-01-01

239

Coordinated observations of PHEMU at radio wavelengths.  

NASA Astrophysics Data System (ADS)

We present preliminary results for our study of mutual phenomena of the Galilean satellites performed at radio wavelengths with the Medicina and Noto antennas of the Istituto di Radioastronomia \\textendash{} INAF, and with the Effelsberg 100-m radio telescope of the Max-Planck-Institute for Radioastronomy. Measurements of the radio flux density variation occurred during the mutual occultations of Io by Europa and Ganymede were carried out during the PHEMU09 campaign at K- and Q-band. Flux density variations observed for the first time at radio wavelengths are consistent with the typical optical patterns measured when partial occultations occurred. The flux density drops indicate a non-linear dependence with the percentage of overlapped area.

Pluchino, S.; Schillirò, F.; Salerno, E.; Pupillo, G.; Kraus, A.; Mack, K.-H.

240

Heart Monitoring By Satellite  

NASA Technical Reports Server (NTRS)

The ambulance antenna shown is a specially designed system that allows satellite-relayed two-way communications between a moving emergency vehicle and a hospital emergency room. It is a key component of a demonstration program aimed at showing how emergency medical service can be provided to people in remote rural areas. Satellite communication permits immediate, hospital- guided treatment of heart attacks or other emergencies by ambulance personnel, saving vital time when the scene of the emergency is remote from the hospital. If widely adopted, the system could save tens of thousands of lives annually in the U.S. alone, medical experts say. The problem in conventional communication with rural areas is the fact that radio signals travel in line of sight. They may be blocked by tall buildings, hills and mountains, or even by the curvature of the Earth, so signal range is sharply limited. Microwave relay towers could solve the problem, but a complete network of repeater towers would be extremely expensive. The satellite provides an obstruction-free relay station in space.

1978-01-01

241

Radio tracking of solar energetic particles through interplanetary space.  

NASA Technical Reports Server (NTRS)

Satellite observations of traveling solar radio bursts provide information about the propagation of energetic solar particles through interplanetary space. This information leads to data on the solar wind density and gross magnetic field configuration over distances of 1 AU. By placing a radio telescope well above the ionosphere it is possible to observe the radio emission down to frequencies that correspond to emission at distances of the order of 1 AU. The observations reported provide the first 'radio picture' over 1 AU of the spiral magnetic field configuration in interplanetary space.

Fainberg, J.; Evans, L. G.; Stone, R. G.

1972-01-01

242

Youth Radio  

NSDL National Science Digital Library

With an impressive headquarters in downtown Oakland, Youth Radio is fast becoming a compelling and insightful media phenomenon that should be watched closely. Their mission is a laudable one, and as their website puts it, âÂÂâ¦. is to promote young peopleâÂÂs intellectual creative and professional growth through training and access to media and to produce the highest quality original media for local and national outlets.â Of course, the real heart of the site contains the actual programming, which is streamed 24 hours a day, 7 days a week. Along with unique mix of music, individuals can listen to a host of stories reported by young people. Visitors can also browse a list of recently added stories by topic, which include relationships, society, sports, poetry, and health. Those who are hoping to get some of the basic flavor of the offerings here would do well to take a look at the story featuring reporting from a group of Berkeley High School students at the World Social Forum in Caracas, or by listening to the commentary offered by Lauryn Silverman on the modern conundrum of multi-tasking.

243

Satellite Images  

NSDL National Science Digital Library

In this online, interactive module, students learn about the three types of satellite images (visible, infrared, and water vapor); how to identify basic cloud types and storm systems in satellite images; and demonstrate the basic knowledge necessary to interpret satellite observations. The module is part of an online course for grades 7-12 in satellite meteorology, which includes 10 interactive modules. The site also includes lesson plans developed by teachers and links to related resources. Each module is designed to serve as a stand-alone lesson, however, a sequential approach is recommended. Designed to challenge students through the end of 12th grade, middle school teachers and students may choose to skim or skip a few sections.

244

Leo satellite-based telecommunication network concepts  

NASA Technical Reports Server (NTRS)

Design considerations are discussed for Low Earth Orbit (LEO) satellite based telecommunications networks. The satellites are assumed to be connected to each other via intersatellite links. They are connected to the end user either directly or through gateways to other networks. Frequency reuse, circuit switching, packet switching, call handoff, and routing for these systems are discussed by analogy with terrestrial cellular (mobile radio) telecommunication systems.

Aiken, John G.; Swan, Peter A.; Leopold, Ray J.

1991-01-01

245

Artificial Satellite  

NASA Astrophysics Data System (ADS)

A man-made object placed in orbit round the Earth or some other celestial body. The first artificial Earth satellite was Sputnik 1, launched by the then Soviet Union, on 4 October 1957. Spherical in shape, and with a mass of 84 kg, it entered an orbit with a perigee altitude of 229 km, an apogee altitude of 947 km and a period of 96 min. Artificial satellites are used for a wide variety of roles,...

Murdin, P.

2000-11-01

246

Monitoring Radio Frequency Interference in Southwest Virginia  

NASA Astrophysics Data System (ADS)

The radio signals received from astronomical objects are extremely weak. Because of this, radio sources are easily shrouded by interference from devices such as satellites and cell phone towers. Radio astronomy is very susceptible to this radio frequency interference (RFI). Possibly even worse than complete veiling, weaker interfering signals can contaminate the data collected by radio telescopes, possibly leading astronomers to mistaken interpretations. To help promote student awareness of the connection between radio astronomy and RFI, an inquiry-based science curriculum was developed to allow high school students to determine RFI levels in their communities. The Quiet Skies Project_the result of a collaboration between the National Aeronautics and Space Administration (NASA), the National Science Foundation (NSF), and the National Radio Astronomy Observatory (NRAO)_encourages students to collect and analyze RFI data and develop conclusions as a team. Because the project focuses on electromagnetic radiation, it is appropriate for physics, physical science, chemistry, or general science classes. My class-about 50 students from 15 southwest Virginia high schools-participated in the Quiet Skies Project and were pioneers in the use of the beta version of the Quiet Skies Detector (QSD), which is used to detect RFI. Students have been involved with the project since 2005 and have collected and shared data with NRAO. In analyzing the data they have noted some trends in RFI in Southwest Virginia.

Rapp, Steve

2010-01-01

247

Mobile Satellite Bands Between 1-30 GHz  

NASA Technical Reports Server (NTRS)

The recent surge in mobile and personal communications has placed new demands on radio spectrum usage in the Earth-to-space direction. In response to this demand, the 1992 World Administrative Radio Conference (WARC-92) revised the table of frequency allocations for mobile-satellite applications.

Davarian, F.; Robbins, P.

1994-01-01

248

Introduction to satellite constellations orbital types, uses and related facts  

E-print Network

military; then Russian satellite television in 1960s. 63.4º inclination. #12;Molnya · Molnya (0.5sd ~12hr) and Tundra (~24hr 1sd orbits) ­ cover high latitudes at apogee. · Invented by Soviet military; then Russian shown for scale · Sirius Radio adopts this model over the continental US. (XM Radio has two GEO

Wood, Lloyd

249

The Mexican national satellite system  

NASA Astrophysics Data System (ADS)

The satellites, tracking, telemetry, command, and monitoring facilities, and the earth station complex for the Mexican national satellite system, Morelos, are described. The spacecraft are intended to provide educational television, rural telephony, data transmission, and business and industrial services. Scheduled for 1985 launch, the satellites will be placed in GEO and use the C and Ku bands with 12 narrow band and six wideband transponders. Spin-stabilized and solar cell powered, the functional mass will be 666 kg, including propellant. The solar panels will provide 940 W of power and 830 W will be available from NiCd batteries during eclipse conditions. The earth station will be located at Iztapalapa, which will have a 12 m antenna, redundant uplink and downlink radios, and command and ranging equipment. Back-up capability will be provided by a station at Tulancingo. Ku band and C band stations are in planning.

Sanchez Ruiz, M. E.; Briskman, R. D.

1983-10-01

250

The American mobile satellite system  

NASA Technical Reports Server (NTRS)

During 1989, the American Mobile Satellite Corporation (AMSC) was authorized to construct, launch, and operate satellites to provide mobile satellite services (MSS) to the U.S. and Puerto Rico. The AMSC has undertaken three major development programs to bring a full range of MSS services to the U.S. The first program is the space segment program that will result in the construction and launch of the satellites as well as the construction and installation of the supporting ground telemetry and command system. The second segment will result in the specification, design, development, construction, and installation of the Network Control System necessary for managing communications access to the satellites, and the specification and development of ground equipment for standard circuit switched and packet switched communications services. The third program is the Phase 1 program to provide low speed data services within the U.S. prior to availability of the AMSC satellites and ground segment. Described here are the present status and plans for these three programs as well as an update on related business arrangements and regulatory matters.

Garner, William B.

1990-01-01

251

The American mobile satellite system  

NASA Astrophysics Data System (ADS)

During 1989, the American Mobile Satellite Corporation (AMSC) was authorized to construct, launch, and operate satellites to provide mobile satellite services (MSS) to the U.S. and Puerto Rico. The AMSC has undertaken three major development programs to bring a full range of MSS services to the U.S. The first program is the space segment program that will result in the construction and launch of the satellites as well as the construction and installation of the supporting ground telemetry and command system. The second segment will result in the specification, design, development, construction, and installation of the Network Control System necessary for managing communications access to the satellites, and the specification and development of ground equipment for standard circuit switched and packet switched communications services. The third program is the Phase 1 program to provide low speed data services within the U.S. prior to availability of the AMSC satellites and ground segment. Described here are the present status and plans for these three programs as well as an update on related business arrangements and regulatory matters.

Garner, William B.

252

Battery voltage variations and radio transmitter temperatures of the small spacecraft  

NASA Astrophysics Data System (ADS)

Diurnal variations of the storage battery voltages as well as temperatures of the radio transmitters on board the small satellite "Universitetsky" have been revealed. Double-humped dependences have been found, related to changes of the micro satellite position relative to the Earth and the Sun and to the on-board satellite systems' operation.

Shakhparonov, V. M.; Karagioz, O. V.

2014-05-01

253

Radio frequency detection assembly and method for detecting radio frequencies  

DOEpatents

A radio frequency detection assembly is described and which includes a radio frequency detector which detects a radio frequency emission produced by a radio frequency emitter from a given location which is remote relative to the radio frequency detector; a location assembly electrically coupled with the radio frequency detector and which is operable to estimate the location of the radio frequency emitter from the radio frequency emission which has been received; and a radio frequency transmitter electrically coupled with the radio frequency detector and the location assembly, and which transmits a radio frequency signal which reports the presence of the radio frequency emitter.

Cown, Steven H. (Rigby, ID); Derr, Kurt Warren (Idaho Falls, ID)

2010-03-16

254

Alaska's giant satellite network  

NASA Astrophysics Data System (ADS)

The evolution and features of the Alaskan telecommunications network are described, with emphasis on the satellite links. The Alaskan terrain is rugged and largely unpopulated. Satcom V provides C-band (6/4 GHz) transmission with 24 transponders, each having a 40 MHz bandwidth. The Alascom company operated 105 4.5 m earth-based antennas for remote villages, which receive both telephone and television services. There are also 27 10-m dishes for regional and military applications and a 30 m dish, one of three dishes for links to the centerminous U.S. Currently, half the villages have private and business telephone communications facilities and 200 villages have access to two television stations, one educational, one entertainment. Teleconferencing is possible for government and educational purposes, and discussions are underway with NASA to establish a mobile radio communications capacity.

Hills, A.

1983-07-01

255

Highlights of the Public Radio Programming Study, Fiscal Year 1996. CPB Research Notes, No. 105.  

ERIC Educational Resources Information Center

The Corporation for Public Broadcasting funded a national study of public radio programming since 1986. The 1996 programming study was conducted by National Public Radio's Audience Research department and had participation by 633 stations. Two-thirds of the stations reported broadcasting 24 hours per day, compared to one-third of stations in 1986.…

Ryan, Lisa Nackerud

256

Educational Radio. What the Research Says. A Literature Survey. Internal Report.  

ERIC Educational Resources Information Center

This review of the literature on educational radio covers reports on research from many areas of the world. Prepared as an internal report for the South African Broadcasting Corporation (SABC) and Educational Radio and Television (ERTV), it was intended to provide a basis for both fruitful discussions and more specific and practical local…

Duby, Aliza

257

Public Radio/Television Survey; Report 3: PTV On-Air Fund Raising.  

ERIC Educational Resources Information Center

The third in a series of four, this report describes part of a national study commissioned by the Corporation for Public Broadcasting to investigate audience awareness of public radio, reaction to on-air fund raising and programing on public radio, and audience reactions to on-air fund raising by public television stations. This segment of the…

Corporation for Public Broadcasting, Washington, DC.

258

Public Radio/Television Survey; Report 1: Public Awareness, Listening, and Programming.  

ERIC Educational Resources Information Center

The first in a series of four, this report describes part of a national study commissioned by the Corporation for Public Broadcasting to investigate audience awareness of public radio, reaction to on-air fund raising and programing on public radio, and audience reactions to on-air fund raising by public television stations. Specifically, this…

Corporation for Public Broadcasting, Washington, DC.

259

The satellite communications alternative for maritime safety  

NASA Astrophysics Data System (ADS)

The current status of satellite communication technology for maritime users is surveyed, with an emphasis on emergency communication capabilities. Topics addressed include the organizational structure of Inmarsat, the present and planned Inmarsat space segment, the coastal and ship earth stations, the compact Standard-C terminal, the Enhanced Group Call system, and the L-band Satellite Emergency Position Indicating Radio Beacon. Consideration is given to the services available to Standard-C stations, distress and safety communication procedures, and the use of satellite communication to disseminate weather information. The equipment costs for various ship installations are indicated in a table.

Fear, James L.

1988-10-01

260

Communications Satellite Receiver Systems for Public Schools: A Technical Primer.  

ERIC Educational Resources Information Center

Designed to aid school districts contemplating use of some of the telecommunications services now available by satellite, this document contains information on home satellite receiving dishes (Television Receive-Only--TVROs), which can receive radio signals carrying television, sound, and data. This information includes: some factors involved in…

Texas Education Agency, Austin.

261

Aeronautical mobile satellite service: Air traffic control applications  

NASA Technical Reports Server (NTRS)

Canada's history both in aviation and in satellite communications development spans several decades. The introduction of aeronautical mobile satellite communications will serve our requirements for airspace management in areas not served by line-of-sight radio and radar facilities. The ensuing improvements in air safety and operating efficiency are eagerly awaited by the aviation community.

Sim, Dave

1990-01-01

262

Antenna systems for mobile satellite applications  

Microsoft Academic Search

In the beginning of radio development, mobile communication systems were conceived for the transmission and receiving of telegraphy and telephony signals via mobile antenna at first from ships, and then from cars, trains and aircraft. The consideration of antenna transmission is inevitable, especially in Global Mobile Satellite Communications (GMSC), where their propagation characteristics are much affected by different and changeable

S. D. Ilcev

2009-01-01

263

Satellite Doppler data processing using a microcomputer  

NASA Technical Reports Server (NTRS)

A microcomputer which was developed to compute ground radio beacon position locations using satellite measurements of Doppler frequency shift is described. Both the computational algorithms and the microcomputer hardware incorporating these algorithms were discussed. Results are presented where the microcomputer in conjunction with the NIMBUS-6 random access measurement system provides real time calculation of beacon latitude and longitude.

Schmid, P. E.; Lynn, J. J.

1977-01-01

264

Antennas For Receiving Signals Broadcast Via Satellites  

NASA Technical Reports Server (NTRS)

Four different antennas designed for use in receiving radio AM and FM signals broadcast via Earth-orbiting satellites at carrier frequency of 2.05 GHz in right-hand circular polarization. Antennas small, lightweight, inexpensive units with low-to-medium-gain, quasi-omnidirectional radiation patterns. Designed for outdoor and indoor uses.

Wu, Te-Kao; Huang, John

1996-01-01

265

Creating corporate advantage.  

PubMed

What differentiates truly great corporate strategies from the merely adequate? How can executives at the corporate level create tangible advantage for their businesses that makes the whole more than the sum of the parts? This article presents a comprehensive framework for value creation in the multibusiness company. It addresses the most fundamental questions of corporate strategy: What businesses should a company be in? How should it coordinate activities across businesses? What role should the corporate office play? How should the corporation measure and control performance? Through detailed case studies of Tyco International, Sharp, the Newell Company, and Saatchi and Saatchi, the authors demonstrate that the answers to all those questions are driven largely by the nature of a company's special resources--its assets, skills, and capabilities. These range along a continuum from the highly specialized at one end to the very general at the other. A corporation's location on the continuum constrains the set of businesses it should compete in and limits its choices about the design of its organization. Applying the framework, the authors point out the common mistakes that result from misaligned corporate strategies. Companies mistakenly enter businesses based on similarities in products rather than the resources that contribute to competitive advantage in each business. Instead of tailoring organizational structures and systems to the needs of a particular strategy, they create plain-vanilla corporate offices and infrastructures. The company examples demonstrate that one size does not fit all. One can find great corporate strategies all along the continuum. PMID:10179655

Collis, D J; Montgomery, C A

1998-01-01

266

Communication protocols and on-board processor for a new national scale private mobile radio service [medical information environment  

Microsoft Academic Search

A satellite-aided mobile radio communication service opens a new horizon of the integrated medical information environment. Doctors of medicine working on fixed or mobile stations, located in remote geographical areas, are able to communicate\\/cooperate each other by exchanging, handling and processing medical data simultaneously. The authors present a new national scale private mobile radio service using satellite facilities. This new

S. Kotsopoulos; D. Lymberopoulos

1992-01-01

267

Activities of Canadian Satellite Communications, Inc.  

NASA Astrophysics Data System (ADS)

Canadian Satellite Communications (Cancom) has as its core business the provision of television and radio signals to cable systems in Canada, with the objective of making affordable broadcast signals available to remote and/or small communities. Cancom also provides direct-to-home services to backyard receiving dishes, as well as satellite digital data business communications services, satellite business television, and satellite network services. Its business communication services range from satellite links for big-city businesses with small branch operations located far from major centers, to a mobile messaging and tracking system for the trucking industry. Revenues in 1992 totalled $48,212,000 and net income was just over $7 million. Cancom bought 10 percent interest in Leosat Corp. of Washington, DC, who are seeking approval to operate a position locator network from low-orbit satellites. Cancom has also become a partner in SovCan Star Satellite Communications Inc., which will build an international satellite system in partnership with Russia. The first satellite in this east-west business network will be placed in a Russian orbital slot over the Atlantic by 1996, and a second satellite will follow for the Pacific region. This annual report of Cancom's activities for 1992 includes financial statements and a six year financial review.

1992-12-01

268

Coping with Radio Frequency Interference  

NASA Astrophysics Data System (ADS)

The radio spectrum is a finite resource, on which humanity makes many demands. And pressure on it is ever increasing with the development of new technology and ideas for radio services. After all, we all benefit from wifi and cell phones. Radio astronomers have a small percentage of the spectrum allocated to them at octave intervals in the metre-centimetre bands, and at important frequencies, such as that of the 21cm line of HI. Signals from other services, as well as from our own poorly-engineered equipment, sometimes contaminate our bands: these signals constitute RFI. These may totally obliterate the astronomical signal, or, in the case of CLOUDSAT, may be capable of completely destroying a receiver, which introduces us to the new possibility of 'destructive interference'. A geo-stationary satellite can block access to a piece of sky from one site. Good equipment design eliminates self-inflicted interference, while physical separation often provides adequate practical mitigation at many frequencies. However, new observatories end up being located in the West Australian desert or Antarctica. In future they may be on the back side of the Moon. But there is no Earth-bound protection via physical separation against satellite signals. Some mitigation can be achieved by frequent data dumps and the excision of RFI, or by real-time detection and blanking of the receiver, or by more sophisticated algoriths. Astronomers of necessity aim to achieve mitigation via coordination, at the local level, and by participating in spectrum management at the national and international levels. This involves them spending a lot of time in Geneva at the International Telegraphic Union protecting their access to spectrum, and access to clean spectrum from the L3 point and the far side of the Moon.

Lewis, B. M.

2009-01-01

269

Jupiter: Satellites  

Microsoft Academic Search

As befitting the king of the planets, JUPITER is orbited by an entourage of at least 39 natural satellites in addition to its faint rings, intense radiation belts and occasional temporary visitors from Earth and the outer solar system. Named after Zeus' lovers and other mythological companions, Jupiter's moons can be divided into four groups on the basis of their

P. Geissler

2003-01-01

270

Satellite Telecommunications.  

ERIC Educational Resources Information Center

This issue of a quarterly publication of the Council of Europe covers aspects of the history, technology, policies, and impact of telecommunications in Europe, with an emphasis on European television. The following articles are included: (1) "Man and the World of Telecommunications" (Piet Stoffelen); (2) "The European Communications Satellite

Forum, 1986

1986-01-01

271

The carbon nanotube radio  

Microsoft Academic Search

The characteristics of the nanotube radio are improved considering new configurations based on quantum tunneling. In this way, the new invented nanotube radio could be tuned electrically in the entire FM or AM bands and biased with miniaturized batteries.

M. Dragoman; D. Dragoman

2008-01-01

272

The GLOMR satellite payload G-308  

NASA Technical Reports Server (NTRS)

The Global Low Orbiting Message Relay (GLOMR) Satellite and its participation in the pioneering development of a Get Away Special (GAS) satellite launch capability is described. The GLOMR is a data relay communication satellite. Experiment objectives are to demonstrate the store-forward relay of data/messages and the communication to ground user equipment. The 150 pound brass satellite, powered by lead acid batteries and solar cells, includes processing, control and radio frequency electronics for data message handling and storage. The GLOMR is mounted through a Marman clamp ejection/retention pedestal to a five cubic foot GAS canister bottom plate. The GAS canister includes a Full Diameter Motorized Door Assembly lid which is opened remotely by astronauts for satellite launch.

1986-01-01

273

Triggered Jovian radio emissions  

NASA Technical Reports Server (NTRS)

Certain Jovian radio emissions seem to be triggered from outside, by much weaker radio waves from the sun. Recently found in the Voyager observations near Jupiter, such triggering occurs at hectometric wavelengths during the arrival of solar radio bursts, with the triggered emissions lasting sometimes more than an hour as they slowly drifted toward higher frequencies. Like the previous discovery of similar triggered emissions at the earth, this suggests that Jupiter's emissions might also originate from natural radio lasers.

Calvert, W.

1985-01-01

274

Satellite communication from user to user  

NASA Astrophysics Data System (ADS)

Satellite communication systems which allow a multitude of user-to-user, point-to-point, and multipoint connections, are presented. The bit rates are 64 kbit/sec and multiples, up to 1.92 Mbit/sec. If required, the ground-stations are installed at the customer's site or at suitable locations in order to serve several customers. However, technical requirements for station location have also to be fulfulled, in order to avoid interference with terrestrial radio services. The increasing number of participants to Satellite Multi Service and INTELSAT Business Services imposes the solution of the problem of communication using cheap techniques. The changes of the German Federal Post Office also permit the economic use of satellite radio techniques for short distances.

Gern, Manfred

275

Corporate governance: quo vadis?  

Microsoft Academic Search

Purpose – This paper aims to examine current research trends into corporate governance and to propose a different dynamic, humanistic approach based on individual purpose, values and psychology. Design\\/methodology\\/approach – The paper reviews selected literature to analyse the assumptions behind research into corporate governance and uses a multi-disciplinary body of literature to present a different theoretical approach based at the

E. Isaac Mostovicz; Nada K. Kakabadse; Andrew Kakabadse

2011-01-01

276

Corporate Conduct Quarterly  

NSDL National Science Digital Library

_Corporate Conduct Quarterly_ is published by the Forum for Policy Research and Public Service at Rutgers, The State University of New Jersey, Camden Campus. The journal aims to offer practical advice on "corporate ethics and compliance." Visitors to the site will find an index of past articles; selected articles are available in full text.

277

Corporate and Business Plan  

E-print Network

Corporate and Business Plan 2010-2011 #12;Main addresses Forest Research Alice Holt Lodge Farnham Research's Business Plan 2010-2011 ..........................12 Table Contents Table 1 - Income This Corporate and Business Plan sets out FR's aims and strategic objectives. It describes the Key Performance

278

Entering the Corporate Market.  

ERIC Educational Resources Information Center

This seminar guide was designed for use with a series of slides in training administrators to market an educational program or service to corporations. The seminar explains the following eight stages in planning entry into the corporate market: identifying appropriate publics; researching the market (analyzing supply and demand, collecting data,…

Greenshields, Garry W.

279

Nanosail-D: The Small Satellite That Could!  

NASA Technical Reports Server (NTRS)

Three years from its initial design review, NanoSail-D successfully deployed its sail on January 20th, 2011. It became the first solar sail vehicle to orbit the earth and the second sail ever unfurled in space. The NanoSail-D mission had two main objectives: eject a nanosatellite from a microsatellite; deploy its sail from a highly compacted volume and low mass system to validate large structure deployment and potential de-orbit technologies. These objectives were successfully achieved and the de-orbit analysis is in process. This paper presents an overview of the NanoSail-D project and insights into how potential setbacks were overcome. Many lessons have been learned during these past three years and are discussed in light of the phenomenal success and interest that this small satellite has generated. NanoSail-D was jointly designed and built by NASA's Marshall Space Flight Center and NASA's Ames Research Center. ManTech/NeXolve Corporation also provided key sail design support. The NanoSail-D experiment is managed by Marshall and jointly sponsored by the Army Space and Missile Defense Command, the Von Braun Center for Science and Innovation and Dynetics Inc. Ground operations support was provided by Santa Clara University, with radio beacon packets received from amateur operators around the world.

Alhorn, Dean C.; Casas, Joseph P.; Agasid, Elwood F.; Adams, Charles L.; Laue, Greg; Kitts, Christopher; O'Brien, Sue

2011-01-01

280

Satellite broadcast usage and life test of high power S-band Traveling Wave Tube Amplifiers  

NASA Astrophysics Data System (ADS)

Broadcasting radio programs from satellites to mobile users has been operating for many years in the United States, Canada and South Korea. The service, generally called Satellite Radio, is provided at S-band radio frequencies. Satellite Radio users require near perfect service availability. Since most users are mobile (automobiles and handheld reception), the antennas of their receivers have little gain necessitating very high effective isotropic radiated power (EIRP) from the satellite to provide the required availability particularly under fading conditions. Despite using a satellite directive transmitting antenna, the achievement of this high EIRP requires a satellite transmitter radio frequency power output of over 7 kW. This is typically achieved by paralleling 32 Traveling Wave Tube Amplifiers (TWTAs). The configuration, usage and technical aspects of such satellite transmitters are described. These satellite transmitters are critical to Satellite Radio service both for performance and for operating lifetime, typically over 15 years. Because of this importance, detailed lifetime laboratory testing is being done on the TWTAs as reported herein.

Bosch, Ernst; Briskman, Robert D.; Foust, Joseph V.; Huebner, Karl-Heinz; Strauss, Robert

2012-12-01

281

Cognitive Radio Architecture Evolution  

Microsoft Academic Search

The radio research community has aggressively embraced cognitive radio for dynamic radio spectrum management to enhance spectrum usage, e.g., in ISM bands and as secondary users in unused TV bands, but the needs of the mobile wireless user have not been addressed as thoroughly on the question of high quality of information (QoI) as a function of place, time, and

Joseph Mitola

2009-01-01

282

Educational Radio 1972.  

ERIC Educational Resources Information Center

A synopsis of educational radio in this country today includes a brief history, figures on the growth of educational radio, rules and regulations governing it, procedures for filing an application for a station, suggestions for financing, and lists of organizations and government agencies concerned with educational radio. (JK)

Federal Communications Commission, Washington, DC.

283

Galileo radio science investigations  

Microsoft Academic Search

The radio science investigations planned for Galileo's 6-year flight to and 2-year orbit of Jupiter use as their instrument the dual-frequency radio system on the spacecraft operating in conjunction with various US and German tracking stations on Earth. The planned radio propagation experiments are based on measurements of absolute and differential propagation time delay, differential phase delay, Doppler shift, signal

H. T. Howard; V. R. Eshleman; D. P. Hinson; A. J. Kliore; G. F. Lindal; R. Woo; M. K. Bird; H. Volland; P. Edenhoffer; M. Paetzold; H. Porsche

1992-01-01

284

Who's Running College Radio?  

ERIC Educational Resources Information Center

While management styles and theories differ among administrators of college radio stations, the views concerning the operation of college radio tend to be consistent. Common elements present in varying degrees in every college radio stations include public broadcasting philosophy, community needs, management and staff, financing, school relations,…

Sauls, Samuel J.

285

Introduction Big Radio Data  

E-print Network

Introduction VLBI Pulsars Summary Big Radio Data Ue-Li Pen CITA, UofT, CIFAR July 3, 2014U. Pen Big Radio Data #12;Introduction VLBI Pulsars Summary Overview History VLBI Processing Future U. Pen Big signal processing U. Pen Big Radio Data #12;Introduction VLBI Pulsars Summary VLBI Current experiments

Prodiæ, Aleksandar

286

Commercial Radio as Communication.  

ERIC Educational Resources Information Center

Compares the day-to-day work routines of commercial radio with the principles of a theoretical communication model. Illuminates peculiarities of the conduct of communication by commercial radio. Discusses the application of theoretical models to the evaluation of practicing institutions. Offers assessments of commercial radio deriving from…

Rothenbuhler, Eric W.

1996-01-01

287

Earthwatch Radio: Vanishing Act in the Arctic  

NSDL National Science Digital Library

This radio broadcast features an expert in the study of the Arctic climate who has analyzed more than 20 years of satellite images that show the steady shrinking of the reflective ice cover of the Arctic Ocean. He points out that the disappearing ice cover is highly reflective and is being replaced by dark-colored ocean that absorbs more heat, and that the melting is accelerating. He also warns that the changes may be irreversible. The clip is 2 minutes in length.

Hoops, Richard

2012-02-28

288

Kids Interactive Telecommunications Project by Satellite (KITES): A Telecommunications Partnership To Empower Middle School Students.  

ERIC Educational Resources Information Center

Kids Interactive Telecommunications Project by Satellite (KITES) is a cooperative international telecommunications partnership involving the University of Lowell, Digital's corporate video network, Videostar Connections Inc. (a satellite networking broker), PanAmSat (a satellite operator), and several other public education institutions in…

LeBaron, John

289

The Earth as a Radio Source: Terrestrial Kilometric Radiation  

Microsoft Academic Search

Radio wave experiments on the Imp 6 and 8 satellites have shown that the earth emits very intense electromagnetic radiation in the frequency range of about 50-500 kHz. At peak intensity the total power emitted in this frequency range is about l09 W. The earth is therefore a very intense planetary radio source, with a total power output comparable to

Donald A. Gurnett

1974-01-01

290

The earth as a radio source - Terrestrial kilometric radiation  

NASA Technical Reports Server (NTRS)

Based on Imp 6 and 8 satellite observation data, a comprehensive study of terrestrial kilometric radiation is presented. In the light of these data, the earth appears to be a very intense planetary radio source, with a total power output comparable to the decametric radio emission from Jupiter. Terrestrial kilometric (i.e., about 50-500 kHz) radiation seems to originate from low altitudes in the auroral region.

Gurnett, D. A.

1974-01-01

291

A research program based on the optical tracking of artificial earth satellites  

Microsoft Academic Search

The tracking of artificial earth satellites is here viewed as an integrated research program. The physical and orbital specifications of the first U.S. satellites are assumed in the tracking program planned under an assignment made to the Smithsonian Astrophysical Observatory by the IGY Satellite Committee of the National Academy of Sciences. The optical program involves early acquisition tracking by (radio

F. Whipple; J. Hynek

1956-01-01

292

Virtual Satellite  

NASA Technical Reports Server (NTRS)

Virtual Satellite (VirtualSat) is a computer program that creates an environment that facilitates the development, verification, and validation of flight software for a single spacecraft or for multiple spacecraft flying in formation. In this environment, enhanced functionality and autonomy of navigation, guidance, and control systems of a spacecraft are provided by a virtual satellite that is, a computational model that simulates the dynamic behavior of the spacecraft. Within this environment, it is possible to execute any associated software, the development of which could benefit from knowledge of, and possible interaction (typically, exchange of data) with, the virtual satellite. Examples of associated software include programs for simulating spacecraft power and thermal- management systems. This environment is independent of the flight hardware that will eventually host the flight software, making it possible to develop the software simultaneously with, or even before, the hardware is delivered. Optionally, by use of interfaces included in VirtualSat, hardware can be used instead of simulated. The flight software, coded in the C or C++ programming language, is compilable and loadable into VirtualSat without any special modifications. Thus, VirtualSat can serve as a relatively inexpensive software test-bed for development test, integration, and post-launch maintenance of spacecraft flight software.

Hammrs, Stephan R.

2008-01-01

293

Radio Science Concepts and Approaches for Jupiter Icy Moons Orbiter  

NASA Technical Reports Server (NTRS)

Radio Science experiments have been conducted on most deep space missions leading to numerous scientific discoveries. A set of concepts and approaches are proposed for the Jupiter Icy Moons Orbiter (JIMO) to apply Radio Science tools to investigate the interior structures of the Galilean Satellites and address key questions on their thermal and dynamical evolution. Measurements are identified that utilize the spacecraft's telecommunication system. Additional instruments can augment these measurements in order to leverage observational synergies. Experiments are also offered for the purpose of investigating the atmospheres and surfaces of the satellites.

Anderson, J. D.; Asmar, S. W.; Castillo, J. C.; Folkner, W. M.; Konopliv, A. S.; Marouf, E. A.; Rappaport, N. J.; Schubert, G.; Spilker, T. R.; Tyler, G. L.

2003-01-01

294

How Satellites Work  

NSDL National Science Digital Library

Collection of seven classroom activities that focus on satellite technology. Topics include: coordinated universal time (UTC); satellite pass prediction; satellite design; satellite orbits; satellite launching; and, use of satellites in at-sea rescues. Each activity provides list of materials needed, background information, and procedure.

295

Master of Science in Corporate Communication Corporate Communication  

E-print Network

Master of Science in Corporate Communication Corporate Communication Goals and Contents Corporate with the organisation's stakeholders in order to maximise the corpora- tion's reputation capital and thus to guarantee access to strate- gic resources. In this it is a strategic partner of other corporate functions

Krause, Rolf

296

Nonprofit Housing Corporation.  

National Technical Information Service (NTIS)

The report consists of an explanation of the incorporation process as set up under Georgia Law, details concerning various Federal Housing Programs, an analysis of the existing nonprofit housing corporation in Georgia, and recommendations for establishing...

1972-01-01

297

Photocopying by Corporate Libraries.  

National Technical Information Service (NTIS)

This document consists of a nummary discussion of the relevant sections of the new copyright law--Section 107, fair use, and Section 108, reproduction by libraries and archives--supplementary guidelines for corporate libraries developed by the Association...

1978-01-01

298

Encyclopedia of Corporate Governance  

NSDL National Science Digital Library

Encyclopedia of Corporate Governance, or encycogov for short, is created and maintained by Henrik Mathiesen, a PhD candidate at the Department of International Economics and Management at the Copenhagen Business School. Content on the site is divided into two sections: Specific Topics and General Topics. Topics in both sections begin with a paragraph explaining the overarching definition of the principle, and link to a variety of tables, "exhibitions," and models that further illustrate the definition. For example, the Bankruptcy Systems section begins with the definition and is followed up by two tables: "Effects of bankruptcy systems on corporate performance and other kinds of institutions of relevance for corporate governance" and "International corporate governance- Tentative characterizations of legal and empirical state of large firm bankruptcy systems in various countries as of 1980-95: 1) Developing countries. 2)Germany. 3) Japan. 4) Anglo-American countries. 5) Denmark." Also included on the site are references and site users information.

299

Essays in corporate finance  

E-print Network

This thesis consists of three essays covering topics in empirical corporate finance with an emphasis on banking relationships and its effect on liquidity constraints and business growth. In particular, it investigates the ...

Drexler, Alejandro Herman

2009-01-01

300

The Corporate Connection.  

ERIC Educational Resources Information Center

Presents an elementary school principal's account of how he utilized corporate sponsorship to improve science education. The principal and seven teachers obtained grants and then recruited local scientific companies to become involved in their science education programs. (PR)

Moryan, James

1994-01-01

301

Press Release Corporate Communications  

E-print Network

Page: 1/2 Press Release Corporate Communications Karolinenplatz 5 D-64289 Darmstadt Germany Your to establish a reputation for itself in scientific and engineering fields. One of the hindrances involved

Reggelin, Michael

302

The evolving corporate board  

Microsoft Academic Search

In a period of takeover battles and dramatic replacements of top managements, the role of the corporate board of directors is rapidly evolving into a major strategic force in American business. Some companies have enacted \\

Murray Weidenbaum

1995-01-01

303

Cognitive Radio will revolutionize American transportation  

ScienceCinema

Cognitive Radio will revolutionize American transportation. Through smart technology, it will anticipate user needs; detect available bandwidths and frequencies then seamlessly connect vehicles, infrastructures, and consumer devices; and it will support the Department of Transportation IntelliDrive Program, helping researchers, auto manufacturers, and Federal and State officials advance the connectivity of US transportation systems for improved safety, mobility, and environmental conditions. Using cognitive radio, a commercial vehicle will know its driver, onboard freight and destination route. Drivers will save time and resources communicating with automatic toll booths and know ahead of time whether to stop at a weigh station or keep rolling. At accident scenes, cognitive radio sensors on freight and transportation modes can alert emergency personnel and measure on-site, real-time conditions such as a chemical leak. The sensors will connect freight to industry, relaying shipment conditions and new delivery schedules. For industry or military purposes, cognitive radio will enable real-time freight tracking around the globe and its sensory technology can help prevent cargo theft or tampering by alerting shipper and receiver if freight is tampered with while en route. For the average consumer, a vehicle will tailor the transportation experience to the passenger such as delivering age-appropriate movies via satellite. Cognitive radio will enhance transportation safety by continually sensing what is important to the user adapting to its environment and incoming information, and proposing solutions that improve mobility and quality of life.

None

2013-12-06

304

[Anorexia and corporal mediations].  

PubMed

The body, the central point of expression of the anorexic symptom, is an important therapeutic lever.The young anorexic girl protects herself through corporal hypertonicity. This tension is consistent with her fears of seeing her body becoming that of an adult and to feel emotions and sensations with too much force. Corporal mediation consists in helping the young girls get to grips with this body. PMID:23923454

Bureau, Hélène; Moro, Marie Rose

2013-01-01

305

The Impact of Radio Interference on Future Radio Telescopes  

NASA Astrophysics Data System (ADS)

While future radio telescopes will require technological advances from the communications industry interference from sources such as satellites and mobile phones is a serious concern. In addition to the fact that the level of interference is growing constantly the increased capabilities of next generation instruments make them more prone to harmful interference. These facilities must have mechanisms to allow operation in a crowded spectrum. In this report some of the factors which may limit the effectiveness of these mechanisms are investigated. Radio astronomy is unique among other observing wavelengths in that the radiation can be fully sampled at a rate which completely specifies the electromagnetic environment. Knowledge of phases and antennae gain factors affords one the opportunity to attempt to mitigate interference from the astronomical data. At present several interference mitigation techniques have been demonstrated to be extremely effective. However the observational scales of the new facilities will push the techniques to their limits. Processes such as signal decorrelation varying antenna gain and instabilities in the primary beam will have a serious effect on some of the algorithms. In addition the sheer volume of data produced will render some techniques computationally and financially impossible.

Mitchell, Daniel A.; Robertson, Gordon J.; Sault, Robert J.

306

The Corporate Library  

NSDL National Science Digital Library

Launched in the summer of 1999 by two long-term partners in Lens Investment Management, this site "is intended to serve as a central repository for research, study and critical thinking about the nature of the modern global corporation, with a special focus on corporate governance and the relationship between company management, their boards and their shareowners." Along with current awareness articles from the staff of The Corporate Library (TCL) and outside sources including Harvard Business School Working Knowledge, CBSMarketWatch, and McKinsey and Co., the site also provides in-depth special reports on CEO Contracts and on Corporate Governance and Performance. The full-text of Power and Accountability, the book written by The Corporate Library's founders Robert AG Monks and Nell Minow, is also available free of charge. In addition, users may search the entire TCL catalog, which includes 25 years' worth of articles emphasizing the best practices in a variety of areas including disclosure and governance and corporate standing.

Minow, Nell.; Monks, Robert A.

307

FORTE observations of lightning radio-frequency signatures: Capabilities and basic results  

Microsoft Academic Search

The FORTE satellite, launched on August 29, 1997, carries both radio-frequency-receiver and optical (imaging and photometric) payloads for the study of lightning. The radio-frequency (RF) data for the first 7 months of operation are described, both to illustrate the satellite{close_quote}s capabilities and to explain the basic statistical findings so far. FORTE{close_quote}s multichannel RF trigger system represents a significant advance in

Abram R. Jacobson; Stephen O. Knox; Robert Franz; Donald C. Enemark

1999-01-01

308

Corporate reputation: seeking a definition  

Microsoft Academic Search

This article reviews different viewpoints in the marketing literature in an attempt to clearly define the concept of corporate reputation and identify its relationship with corporate image. Definitions offered for the term corporate reputation by marketing academics and practitioners are therefore merged into two dominant schools of thought. These include the analogous school of thought, which views corporate reputation as

Manto Gotsi; Alan M. Wilson

2001-01-01

309

Advancing and enhancing corporate reputation  

Microsoft Academic Search

This article describes corporate reputation as it pertains to corporate practice. Key areas treated are worldwide executive opinion on their ability to affect corporate reputation; three specific strategic benefits and goals of strong corporate reputation (preference in doing business with a company when products\\/services are similar, support for a company in time of controversy, and company value in the financial

Stephen A. Greyser

1999-01-01

310

Corporate Governance and Economic Performance  

Microsoft Academic Search

What is the best corporate governance system? Is the Germanic corporate governance system the best? The Japanese? The Anglo?Saxon? This article reviews some of the relevant literature for answering this question. Particular attention is devoted to corporate governance problems in developing countries. It emphasizes that the nature of problems that corporate governance systems must deal with can be expected to

Dennis C. Mueller

2006-01-01

311

High Energy Astrophysics: Radio Galaxies Geoffrey V. Bicknell Radio Galaxies  

E-print Network

High Energy Astrophysics: Radio Galaxies © Geoffrey V. Bicknell Radio Galaxies 1 Fanaroff Laing #12;High Energy Astrophysics: Radio Galaxies 2/56 The prototype FR 2 radio galaxy, Cygnus A Energy Astrophysics: Radio Galaxies 3/56 Cygnus A at 850 microns. Only the hot spots and core are visible

Bicknell, Geoff

312

The Arctic Regional Communications Small SATellite (ARCSAT)  

NASA Technical Reports Server (NTRS)

Traditional satellite missions are extremely complex and expensive to design, build, test, launch and operate. Consequently many complementary operational, exploration and research satellite missions are being formulated as a growing part of the future space community capabilities using formations of small, distributed, simple to launch and inexpensive highly capable small scale satellites. The Arctic Regional Communications small SATellite (ARCSAT) initiative would launch a Mini-Satellite "Mothership" into Polar or Sun Sync low-earth-orbit (LEO). Once on orbit, the Mothership would perform orbital insertion of four internally stored independently maneuverable nanosatellites, each containing electronically steerable antennas and reconfigurable software-defined radios. Unlike the traditional geostationary larger complex satellite communication systems, this LEO communications system will be comprised of initially a five small satellite formation that can be later incrementally increased in the total number of satellites for additional data coverage. ARCSAT will provide significant enabling capabilities in the Arctic for autonomous voice and data communications relay, Maritime Domain Awareness (MDA), data-extraction from unattended sensors, and terrestrial Search & Rescue (SAR) beacon detection missions throughout the "data starved desert" of the Arctic Region.

Casas, Joseph; Kress, Martin; Sims, William; Spehn, Stephen; Jaeger, Talbot; Sanders, Devon

2013-01-01

313

Harbingers of sputnik: The amateur radio preparations in the Soviet Union  

Microsoft Academic Search

After recapitulating and re?evaluating the principal early signals that the Soviet Union was planning to launch an artificial earth satellite (Sputnik 1) in 1957, which have long been familiar to space historians, this article presents some additional pre?sputnik material from Radio, the Soviet government's monthly magazine for radio amateurs, and from other sources, which has not previously been identified by

Rip Bulkeley

1999-01-01

314

The potential of High Altitude Platforms (HAPS) for low interference and broadband radio services  

Microsoft Academic Search

A description of the use of HAPS for radio systems operation has been presented in this paper with reference to GEO and LEO satellites and terrestrial mobile radio communication systems. The wireless microwave power transmission concept using rectifier antenna (RECTENNA) elements has been presented.

Jacob Gavan; S. Tapuchi

2009-01-01

315

Radio occultation experiments with INAF-IRA radiotelescopes.  

NASA Astrophysics Data System (ADS)

The Radio Occultation research program performed at the Medicina and Noto Radioastronomical Stations of the Istituto Nazionale di Astrofisica (INAF) - Istituto di Radioastronomia (IRA) includes observations of spacecraft by satellite and satellite by satellite events. The Lunar Radio Occultation (LRO) part of the program consists in collecting data of the lunar Total Electron Content (TEC), at different limb longitudes and at different time, in order to study long term variation of the Moon's ionosphere. The LRO program started at Medicina in September 2006 with the observation of the European probe SMART-1 during its impact on the lunar soil. It proceeded in 2007 with the observation of the lunar occultations of Saturn and Venus, and with the observation of Mars in 2008. On this occasion the probes Cassini, Venus Express, Mars Express, Mars Reconaissance Orbiter and Mars Odissey were respectively occulted by the moon. On Dec 1st 2008 a Venus lunar occultation occurred. On that occasion we performed the first Italian-VLBI (I-VLBI) tracking experiment by detecting the carrier signals coming from the Venus Express (VEX) spacecraft with both the IRA radiotelescopes together with the Matera antenna of the Italian Space Agency. The second part of the radio occultation program includes the observation of satellite by satellite occultation events, as well as mutual occultations of Jupiter satellites. These events are referred to as mutual phenomena (PHEMU). These observations are aimed to measure the radio flux variation during the occultation and to derive surface spatial characteristics such as Io's hot spots. In this work preliminary results of the Radio Occultation program will be presented.

Pluchino, S.; Schillirò, F.; Salerno, E.; Pupillo, G.

316

STEM on the radio  

NASA Astrophysics Data System (ADS)

Looking for an Internet radio station focusing on programing about science, technology, engineering, and math (STEM)? The U.S. National Science Foundation (NSF) announced on 26 September the launch of Science360 Radio, which it says is the first Internet radio stream dedicated to STEM programing. Science360 includes more than 100 radio shows and podcasts that are available on the Web as well as on iPhone and Android devices. The shows originate from a variety of sources, including NSF, other U.S. government agencies, science organizations, universities, and media outlets. For more information, see http://science360.gov/files/.

Showstack, Randy

2011-10-01

317

Radio Properties of AGN  

NASA Astrophysics Data System (ADS)

To study the radio properties of AGN, we cross-correlate and investigate Veron-Cetty & Veron catalog of QSOs and Active Galaxies (v.13, 2010) with a number of radio catalogs: NVSS, FIRST, GB6, 87GB, SUMSS, WISH, WENSS, and 7C. This catalog contains 168,940 objects with positional accuracy of mostly 1 arcsec, though many positions have larger errors. We use new cross-correlation software based on accuracy of each object independently. In this software we take into account errors for each source and take identifications with errors within 3 sigma. Altogether, we find ~16,000 AGN having radio detection in any of the listed catalogs. Using all data from radio catalogs, we derive a homogeneous sample of radio AGN. The sample allows accomplish several tasks, including study of the distribution of radio sources by activity types, differences in physical properties of radio-loud and radio-quiet AGN, luminosity functions for various types of radio AGN, study of the q parameter by AGN types and its evolution, etc.

Abrahamyan, Hayk V.; Mickaelian, Areg M.

2014-07-01

318

Radio and distance learning in Pakistan.  

PubMed

Radio is a powerful communication vehicle in Pakistan able to reach 3/4 of urban and 2/3 of rural households. Until 1974, most radio broadcasts of the Pakistan Broadcasting Corporation, a state monopoly, were in the categories of music, drama, and features; news and current affairs; and religious broadcasts. The Allama Iqbal Open University (AIOU), a distance learning educational institution, was established through an act of the Pakistan Parliament in 1974 and is the only institution in the country to use radio broadcasts for its curriculum. Also established in 1974 within the AIOU was the Institute of Educational Technology (IET). The IET channels the transmission and flow of well-designed educational messages and lessons from the teachers to the students by employing distance teaching methodology that seeks to reinforce students' weekly lessons. IET closely integrates its activities within the University's academic departments. IET staff members not only participate in the development of course curriculum and syllabi, but also help to identify course content needing reinforcement through radio. While the teachers at AIOU convert the course curricula into distance-learning self-study activity-oriented correspondence texts, IET producers transcribe these scripts into actual production scripts. Feedback from students and findings of the University's Research and Statistical Cell are used to make revisions in the scripts. The AIOU enrolls an average of 100,000 students each year. Expansion is being limited only by the costs of purchasing time from the Pakistan Broadcasting Corporation (Rs 2000 for a 15-minute lesson) and the availability of appropriate time slots. PMID:12281001

Abbas, R

1987-01-01

319

75 FR 66709 - Commercial Radio Operators Rules  

Federal Register 2010, 2011, 2012, 2013

...General Radiotelephone Operator License, GMDSS Radio Maintainer's License). (2) Six Months...Endorsement, Six Months Service Endorsement, GMDSS Radio Operator's License, Restricted GMDSS Radio Operator's License, GMDSS Radio...

2010-10-29

320

In memoriam: Grote Reber 1911-2002 founder of radio astronomy  

NASA Astrophysics Data System (ADS)

Grote Reber, amateur radio operator W9GFZ, died December 20, 2002 in Tasmania. He would have been 91 years old on December 22nd. Reber is acknowledged as the Father of Radio Astronomy and the inventor of the first true radio telescope. With the advent of space satellites, his greatest legacy may well be his invention of the parabolic dish, designed to receive nonterrestrial electromagnetic radiation, a concept that has revolutionized worldwide communication.

Peratt, A. L.

2003-12-01

321

Unique operations for a highly inclined, elliptical, geosynchronous satellite  

NASA Astrophysics Data System (ADS)

The first space segment devoted to a Digital Audio Radio Service (DARS) for the Continental United States (CONUS) was established when the last satellite of a three satellite constellation (Flight Models FM-1, FM-2 and FM-3) was launched in November 2000. Each satellite is in a highly inclined, elliptical, geosynchronous orbit that is separated by 120° in Right Angle of the Ascending Node (RAAN) from the other two satellites' orbits. This results in an 8 h phasing in ground track between each satellite. These distinct orbits provide superior look angles and signal availability to mobile receivers in the northern third of the United States when compared to geostationary satellites. However, this unique orbital constellation results in some particular performance and operational differences from geostationary orbit satellites. Some of these are: Earth Sensor noise, maneuver implementation and power management. Descriptions and performance improvements of these orbit specific operations are detailed herein.

Anglin, Patrick T.; Briskman, Robert D.

2004-08-01

322

RADIO-SCIENTIFIQUE INTERNATIONALE  

E-print Network

the Earths ionospherebeginningwiththelaunch of Sputnik, died peacefully in his sleep at his home in Newton,asanAirForceCambridgeResearchCenterscientist, taking advantage of the launch of the Sputnik series of satellites in 1957, he formed the Joint Satellite

Goldberg, Bennett

323

Satellite altimetry  

NASA Technical Reports Server (NTRS)

Since altimetry data are not really old enough to use the term data archaeology, Mr. Cheney referred to the stewardship of these data. He noted that it is very important to document the basis for an altimetry data set as the algorithms and corrections used to arrive at the Geophysical Data Record (GDR) have been improving and are continuing to improve the precision of sea level data derived from altimetry. He noted that the GEOSAT Exact Repeat Mission (ERM) data set has recently been reprocessed by his organization in the National Ocean Service of NOAA and made available to the scientific community on CD/ROM disks by the National Oceanographic Data Center of the U.S. (NODC). The new data set contains a satellite orbit more precise by an order of magnitude together with an improved water vapor correction. A new, comprehensive GDR Handbook has also been prepared.

Cheney, Robert E.

1992-01-01

324

Domestic mobile satellite systems in North America  

NASA Technical Reports Server (NTRS)

Telest Mobile Inc. (TMI) and the American Mobile Satellite Corporation (AMSC) are authorized to provide mobile satellite services (MSS) in Canada and the United States respectively. They are developing compatible systems and are undertaking joint specification and procurement of spacecraft and ground segment with the aim of operational systems by late 1993. Early entry (phase 1) mobile data services are offered in 1990 using space segment capacity leased from Inmarsat. Here, an overview is given of these domestic MSS with an emphasis on the TMI component of the MSAT systen.

Wachira, Muya

1990-01-01

325

Domestic mobile satellite systems in North America  

NASA Astrophysics Data System (ADS)

Telest Mobile Inc. (TMI) and the American Mobile Satellite Corporation (AMSC) are authorized to provide mobile satellite services (MSS) in Canada and the United States respectively. They are developing compatible systems and are undertaking joint specification and procurement of spacecraft and ground segment with the aim of operational systems by late 1993. Early entry (phase 1) mobile data services are offered in 1990 using space segment capacity leased from Inmarsat. Here, an overview is given of these domestic MSS with an emphasis on the TMI component of the MSAT systen.

Wachira, Muya

326

Radio Frequency Interference and the National Radio Astronomy Observatory  

NASA Astrophysics Data System (ADS)

Radio frequency interference (RFI) and radio astronomy have been closely linked since the emergence of radio astronomy as a scientific discipline in the 1930s. Even before the official establishment of the National Radio Astronomy Observatory, protection against contemporary and future radio noise levels was seen as crucial to ensure success of any new observatory. My talk will examine the various local, regional, national, and international efforts enacted to protect NRAO and other American radio astronomy sites from RFI.

Smith, Sierra

2014-01-01

327

Corporate Crime Reporter  

NSDL National Science Digital Library

Published since 1986, the Corporate Crime Reporter is a legal newsletter that highlights recent news items about ongoing corporate crime prosecutions, along with featuring interviews with prominent attorneys who work in this rather intriguing field of law practice. The interview section is quite interesting as users can read long-form interviews with major players such as Dan Webb (who was a prosecutor in the Iran-Contra Affair) and Neil Getnick, who prosecuted the Bayer corporation after it was suspected they bilked Medicaid out of approximately $100 million. Visitors can also view various related documents, such as the indictment of Martha Stewart and a Justice Department memo regarding the federal prosecution of business organizations. The site is rounded out by several reports on the top 10 white-collar crime defense lawyers and the top 100 corporate criminals of the 1990s. Overall, the site will be of great interest to legal professionals, or those who are interested in learning more about the complex world of corporate crime in the United States.

328

Swedish small satellites  

Microsoft Academic Search

In 1986 the first Swedish small satellite VIKING was launched on the Ariane I rocket together with the French remote sensing satellite SPOT. This paper describes the development of the Swedish Small Satellite Program. The satellites have delivered excellent scientific data at a low cost by using streamlined project organisations, competitive procurement programs and piggy-back launch opportunities.The first micro satellite

Kaj Lundahl; Fredrik Von Schéele

1998-01-01

329

Far-IR and Radio Continua in Solar Flares  

Microsoft Academic Search

With the invention of new far-infrared (FIR) and radio mm and sub-mm instruments (DESIR on SMESE satellite, ESO ALMA), there is a growing interest in observations and analysis of solar flares in this so far unexplored wavelength region. Two principal radition mechanisms play a role: the synchrotron emission due to accelerated particle beams moving in the magnetic field and the

P. Heinzel; J. Kasparova; M. Varady; M. Karlicky; Z. Moravec

2008-01-01

330

New Developments in Radar and Radio Sensors for Aircraft Navigation  

Microsoft Academic Search

Recent developments in airborne Doppler and ground mapping navigation radars and ground and satellite based radio systems are described. Simultaneous lobing and slope tracking techniques can remove the well-known Doppler sea bias error in fast and slowly moving vehicles. Doppler velocity information can be extracted from coherent forward-looking mapping radars, and high position fixing accuracy can be achieved by synthetic

WALTER R. FRIED

1974-01-01

331

Smart Radio Spectrum Management for Cognitive Radio  

E-print Network

Today's wireless networks are characterized by fixed spectrum assignment policy. The limited available spectrum and the inefficiency in the spectrum usage necessitate a new communication paradigm to exploit the existing wireless spectrum opportunistically. Cognitive radio is a paradigm for wireless communication in which either a network or a wireless node changes its transmission or reception parameters to communicate efficiently avoiding interference with licensed or unlicensed users. In this work, a fuzzy logic based system for spectrum management is proposed where the radio can share unused spectrum depending on some parameters like distance, signal strength, node velocity and availability of unused spectrum. The system is simulated and is found to give satisfactory results.

Bhattacharya, Partha Pratim; Gera, Rishita; Agarwal, Anjali

2011-01-01

332

Satellite observations of transionospheric pulse pairs  

SciTech Connect

The BLACKBEARD payload aboard the ALEXIS satellite has been making broadband observations in the VHF band of the radio spectrum. Since November of 1993 several hundred unusual signals have been recorded. The peculiar nature of these bursts of radio noise is that they have a duration of approximately 10 {mu}sec, are typically 20 to 40 dB brighter than the average background, and occur in pairs separated by approximately 50 {mu}sec. The authors have dubbed these emissions TransIonospheric Pulse Pairs, or TIPP events. They do not know what the source of these emissions is, but the dispersion of these signals is consistent with an origin at or near the earth`s surface. The satellite field of view and time of day when TIPP events are generally detected are consistent with regions of thunderstorm activity such as south-central Africa or Indonesia. 4 refs., 5 figs.

Holden, D.N.; Munson, C.P.; Devenport, J.C. [Los Alamos National Lab., NM (United States)] [Los Alamos National Lab., NM (United States)

1995-04-15

333

The Radio Jove Project  

NASA Technical Reports Server (NTRS)

The Radio love Project is a hands-on education and outreach project in which students, or any other interested individuals or groups build a radio telescope from a kit, operate the radio telescope, transmit the resulting signals through the internet if desired, analyze the results, and share the results with others through archives or general discussions among the observers. Radio love is intended to provide an introduction to radio astronomy for the observer. The equipment allows the user to observe radio signals from Jupiter, the Sun, the galaxy, and Earth-based radiation both natural and man-made. The project was started through a NASA Director's Discretionary Fund grant more than ten years ago. it has continued to be carried out through the dedicated efforts of a group of mainly volunteers. Dearly 1500 kits have been distributed throughout the world. Participation can also be done without building a kit. Pre-built kits are available. Users can also monitor remote radio telescopes through the internet using free downloadable software available through the radiosky.com website. There have been many stories of prize-winning projects, inspirational results, collaborative efforts, etc. We continue to build the community of observers and are always open to new thoughts about how to inspire the observers to still greater involvement in the science and technology associated with Radio Jove.

Thieman, J. R.

2010-01-01

334

Film, Radio, and Television.  

ERIC Educational Resources Information Center

This journal issue covers the history of film, radio, and television in Iowa. The first article, "When Pictures and Sound Came to Iowa," summarizes the origin of movies and radio and their early beginnings in Iowa. Using old photographs and measurement charts, the viewing, reading, and listening habits of young people in 1950 and 1958 are…

Hardesty, Carolyn, Ed.

1990-01-01

335

World Ocean Radio  

NSDL National Science Digital Library

World Ocean Radio is a weekly series of five-minute audio essays on a wide range of ocean issues hosted by W2O's own Peter Neill. Available for RSS feed (bottom of page), podcast, and syndicated use at no cost by community radio stations worldwide.

336

Early Cambridge radio astronomy  

Microsoft Academic Search

Radio astronomy started in Cambridge immediately after the hostilities of the World War II have ceased. Martin Ryle was the inspiring leader of a small group that started to develop interferometry techniques at the Cavendish Laboratory. From this development came the numerous Cambridge radio source surveys culminating in the Nobel prize awarded to Martin Ryle for invention of aperture synthesis.

F. G. Smith

2007-01-01

337

Stabilized radio frequency quadrupole  

DOEpatents

A long-vane stabilized radio frequency resonator for accelerating charged particles and including means defining a radio frequency resonator cavity, a plurality of long vanes mounted in the defining means for dividing the cavity into sections, and means interconnecting opposing ones of the plurality of vanes for stabilizing the resonator.

Lancaster, Henry D. (Orinda, CA); Fugitt, Jock A. (Berkeley, CA); Howard, Donald R. (Danville, CA)

1984-01-01

338

Radio Emission from Exoplanets  

E-print Network

We present results from new low frequency observations of two extrasolar planetary systems (Epsilon Eridani and HD128311) taken at 150 MHz with the Giant Metrewave Radio Telescope (GMRT). We do not detect either system, but are able to place tight upper limits on their low frequency radio emission.

Samuel J. George; Ian R. Stevens

2008-04-24

339

Division x: Radio Astronomy  

Microsoft Academic Search

Division X provides a common theme for astronomers using radio techniques to study a vast range of phenomena in the Universe, from exploring the Earth's ionosphere or making radar measurements in the Solar System, via mapping the distribution of gas and molecules in our own Galaxy and in other galaxies, to study the vast explosive processes in radio galaxies and

Luis F. Rodriguez; Ren-Dong Nan; Lucia Padrielli; Philip J. Diamond; Gloria M. Dubner; Michael Garrett; W. Miller Goss; Anne Green; Masato Ishiguro; A. Pramesh Rao; Russell A. Taylor; Jose M. Torrelles; Jean L. Turner

2007-01-01

340

Radio efficiency of pulsars  

E-print Network

We investigate radio emission efficiency $\\xi$ of pulsars and report a near linear inverse correlation between $\\xi$ and the spindown power $\\dot E$, as well as a near linear correlation between $\\xi$ and pulsar age $\\tau$. This is a consequence of very weak, if any, dependences of radio luminosity $L$ on pulsar period $P$ and period derivative $\\dot{P}$, in contrast to X-ray or $\\gamma$-ray emission luminosities. The analysis of radio fluxes suggests that these correlations are not due to a selection effect, but are intrinsic to the pulsar radio emission physics. We have found that, although with a large variance, the radio luminosity of pulsars is $\\left\\approx 10^{29} \\,{\\rm erg/s}$, regardless of the position in the $P-\\dot P$ diagram. Within such a picture, a model-independent statement can be made that the death line of radio pulsars corresponds to an upper limit in the efficiency of radio emission. If we introduce the maximum value for a radio efficiency into Monte Carlo-based population syntheses we c...

Szary, Andrzej; Melikidze, George; Gil, Janusz; Xu, Ren-Xin

2014-01-01

341

Planetary radio lasing  

NASA Technical Reports Server (NTRS)

Both the Earth's auroral kilometric radiation (AKR) and Jupiter's decametric radio S-bursts are attributed to natural radio lasing. Presumably consisting of self-excited, closed-loop wave feedback oscillations between local irregularities of the source plasma density, this radio lasing is comparable to that which occurs in man-made optical lasers, although at radio, rather than optical wavelengths. As a result, it should produce a multiple discrete emission spectrum and intense, coherent beams. Recent observations of the AKR's discreteness and coherence have clearly ruled out the previous open-loop amplifier model for such emissions, and recent observations of the Jovian S-bursts have shown the expected, regularly-spaced, longitudinal laser modes. These new observations thus confirm the proposed planetary cyclotron radio lasing at both planets.

Calvert, W.

1988-01-01

342

Solar radio continuum storms  

NASA Technical Reports Server (NTRS)

Radio noise continuum emission observed in metric and decametric wave frequencies is discussed. The radio noise is associated with actively varying sunspot groups accompanied by the S-component of microwave radio emissions. It is shown that the S-component emission in microwave frequencies generally occurs several days before the emission of the noise continuum storms of lower frequencies. It is likely that energetic electrons, 10 to 100 Kev, accelerated in association with the variation of sunspot magnetic fields, are the sources of the radio emissions. A model is considered to explain the relation of burst storms on radio noise. An analysis of the role of energetic electrons on the emissions of both noise continuum and type III burst storms is presented. It is shown that instabilities associated with the electrons and their relation to their own stabilizing effects are important in interpreting both of these storms.

1974-01-01

343

Modems for emerging digital cellular-mobile radio system  

NASA Technical Reports Server (NTRS)

Digital modem techniques for emerging digital cellular telecommunications-mobile radio system applications are described and analyzed. In particular, theoretical performance, experimental results, principles of operation, and various architectures of pi/4-QPSK (pi/4-shifted coherent or differential QPSK) modems for second-generation US digital cellular radio system applications are presented. The spectral/power efficiency and performance of the pi/4-QPSK modems (American and Japanese digital cellular emerging standards) are studied and briefly compared to GMSK (Gaussian minimum-shift keying) modems (proposed for European DECT and GSM cellular standards). Improved filtering strategies and digital pilot-aided (digital channel sounding) techniques are also considered for pi/4-QPSK and other digital modems. These techniques could significantly improve the performance of digital cellular and other digital land mobile and satellite mobile radio systems. More spectrally efficient modem trends for future cellular/mobile (land mobile) and satellite communication systems applications are also highlighted.

Feher, Kamilo

1991-01-01

344

Corporate Energy Management Process  

E-print Network

-05-25 Proceedings of the Thrity-Fifth Industrial Energy Technology Conference New Orleans, LA. May 21-24, 2013 BASF North America BASF Corporation (U.S.), BASF Canada, BASF Mexicana ESL-IE-13-05-25 Proceedings of the Thrity-Fifth Industrial Energy Technology...-05-25 Proceedings of the Thrity-Fifth Industrial Energy Technology Conference New Orleans, LA. May 21-24, 2013 BASF North America BASF Corporation (U.S.), BASF Canada, BASF Mexicana ESL-IE-13-05-25 Proceedings of the Thrity-Fifth Industrial Energy Technology...

Geiger, T.

2013-01-01

345

Shuttle station, and satellite communications program  

NASA Technical Reports Server (NTRS)

A parametric approach is developed to analyze and evaluate the performance of any link or links of a satellite relay system. The approach factors into the calculations the constraints of coherent radio frequency interference, multipath, and equipment design. The report is divided into three sections dealing with Spread Spectrum Techniques (Section 1), Power Budget Calculations (Section 2), and Required Capabilities and Design Factors for Tracking and Data Relay Systems TDRS (Section 3).

Lawsine, L.

1974-01-01

346

Link adaptation and receiver design for enhanced General Packet Radio Services wireless networks  

Microsoft Academic Search

Proposes a link adaptation and receiver design scheme for satellite-based Enhanced General Packet Radio Services (EGPRS) wireless networks. Rician flat fading is assumed for the satellite channel. Because there is no intersymbol interferences, so demodulator is one of the most important designs for receiver. The average signal and noise powers in one EGPRS burst is estimated using an unsupervised clustering

Qilian Liang

2002-01-01

347

Capacity as a consideration for providing aeronautical mobile satellite air traffic services in the US domestic airspace  

Microsoft Academic Search

International standards are being developed by the International Civil Aviation Organization for an aeronautical mobile-satellite service (AMSS). Moreover, the American Mobile Satellite Corporation (AMSC) is constructing a satellite communications that could provide this service in US domestic airspace. The author describes a preliminary analysis of the capacity (number of aircraft) that could be handled by the first-generation AMSC system in

C. A. Shively

1992-01-01

348

IMAGE Satellite Scaling  

NSDL National Science Digital Library

This is an activity about satellite size. Learners will calculate the volume of the IMAGE (Imager for Magnetopause-to-Aurora Global Exploration) satellite, the first satellite mission to image the Earth's magnetosphere. They will then determine the effect of doubling and tripling the satellite dimensions on the satellite's mass and cost. This is the first activity in the Solar Storms and You: Exploring Satellite Design educator guide.

349

Corporate Social Responsibility from the Perspective of Corporate Secretaries  

Microsoft Academic Search

\\u000a Corporate secretaries make a considerable contribution to corporate social responsibility (CSR) processes by the nature of\\u000a the positions and responsibilities they hold in organisations. They act as a servant or full member of the board of directors,\\u000a the body that formulates corporate strategies; which are subsequently executed by executive directors. When corporate secretaries\\u000a become full members of the board, they

Samuel O. Idowu

350

Satellite communications in China  

Microsoft Academic Search

The current status of satellite communication technology in China is reviewed. Particular attention is given to satellite communication networks for public service and some specialized communication networks.

Guorui Chen; Warren Stutzman

1991-01-01

351

Operation of the Radio Occultation Mission in KOMPSAT-5  

NASA Astrophysics Data System (ADS)

Korea multi-purpose satellite-5 (KOMPSAT-5) is a low earth orbit (LEO) satellite scheduled to be launched in 2010. To satisfy the precision orbit determination (POD) requirement for a high resolution synthetic aperture radar image of KOMPSAT-5, KOMPSAT-5 has atmosphere occultation POD (AOPOD) system which consists of a space-borne dual frequency global positioning system (GPS) receiver and a laser retro reflector array. A space-borne dual frequency GPS receiver on a LEO satellite provides position data for the POD and radio occultation data for scientific applications. This paper describes an overview of AOPOD system and operation concepts of the radio occultation mission in KOMPSAT-5. We showed AOPOD system satisfies the requirements of KOMPSAT-5 in performance and stability.

Choi, Mansoo; Lee, Woo-Kyoung; Cho, Sungki; Park, Jong-Uk

2010-12-01

352

Corporate Training in Museums  

ERIC Educational Resources Information Center

Museums often court corporate audiences through special event rentals and development and promotional partnerships. But we rarely approach them as potential adult learners. In overlooking them, we miss the potential of reaching a large number of often novice museum participants who can gain from gallery learning and develop a relationship with our…

Causey, Adera

2011-01-01

353

Bottle Rock Power Corporation  

E-print Network

a petition with the CEC pursuant to California Administrative Code Title 20 Section 1769(a). Hence, the BRPC Guy Childs Water Resources Control Engineer Central Valley Regional Water Quality Control Board 3443 Dept. of Fish and Game P.O. Box 47 Yountville, CA 94599 #12;Bottle Rock Power Corporation 3 Nancy

354

Corporate and personal responsibility  

SciTech Connect

Socioeconomic aspects of global climate change are discussed in this paper. Behavioral dimensions are discussed, with a focus on individual and collective value systems. It is suggested that traditional values are not adequate for addressing the climate change issue. Social aspects of the corporate role in climatic change are also briefly discussed.

Jemieson, D. [Univ. of Colorado, Boulder, CO (United States)

1992-12-31

355

Second Corporate Plan.  

ERIC Educational Resources Information Center

The Technical and Further Education (TAFE) National Centre for Research and Development has two broad areas of activity: the undertaking and encouragement of research and development projects that are of national significance to TAFE and the dissemination of information on research and development in TAFE. The center issued its first corporate

TAFE National Centre for Research and Development, Payneham (Australia).

356

Measuring corporate reputation  

Microsoft Academic Search

Considers how corporate reputation is most influenced by the actions of an organization rather than a successful (or otherwise) PR campaign. Then considers how a communication strategy can best influence reputation. It is important to avoid a monologue – deciding the message then conveying it with ruthless efficiency – and move to dialogue – knowing what matters to an audience

Stewart Lewis

2001-01-01

357

Of Corporate Bondage  

ERIC Educational Resources Information Center

"While it is entirely possible that the university will continue to function as an essential arm of the giant agribusiness and energy corporations, there are, nevertheless, a wealth of opportunities for it to direct its energies to more useful purposes." The author traces universities' past involvement noting alternatives in energy and agriculture…

Ridgeway, James

1975-01-01

358

CORPORATIONS APAC Tennessee Incorporated  

E-print Network

and Associates Diversified Financial Group LLC Dixon Hughes Goodman LLP Donaldson Capital Management LLC Dorris Engineers' Club of Memphis Incorporated Ernst and Young LLP Eyewear Gallery Farris Bobango PLLC Fastech Pavilion Memphis Incorporated Funding Factory WLOK Radio Gipson Specialty Center PLLC Glankler Brown PLLC

Dasgupta, Dipankar

359

Propagation considerations in the American Mobile Satellite system design  

NASA Astrophysics Data System (ADS)

An overview of the American Mobile Satellite Corporation (AMSC) mobile satellite services (MSS) system with special emphasis given to the propagation issues that were considered in the design is presented. The aspects of the voice codec design that effect system performance in a shadowed environment are discussed. The strategies for overcoming Ku-Band rain fades in the uplink and downlink paths of the gateway station are presented. A land mobile propagation study that has both measurement and simulation activities is described.

Kittiver, Charles; Sigler, Charles E., Jr.

1993-08-01

360

Corporate governance and insider trading  

E-print Network

I investigate the relation between corporate governance and insider trading by corporate executives. Despite the general view that trade on non-public information adversely affects capital market participants, the impact ...

Rozanov, Konstantin A

2008-01-01

361

Getting to Know the Corporation  

ERIC Educational Resources Information Center

A model is given in which corporations are approached as investors in educational institutions rather than philanthropists. Assumes that corporations should be more responsive to this than to the one-way stream of assets so characteristic in the past.

Neely, George , Jr.

1974-01-01

362

The Illiquidity of Corporate Bonds  

E-print Network

This paper examines the illiquidity of corporate bonds and its asset-pricing implications. Using transactions data from 2003 to 2009, we show that the illiquidity in corporate bonds is substantial, significantly greater ...

Bao, Jack

363

Multiple Radios for Effective Rendezvous in Cognitive Radio Networks  

E-print Network

Multiple Radios for Effective Rendezvous in Cognitive Radio Networks Lu Yu1 , Hai Liu1 , Yiu in cognitive radio networks (CRNs) for establishing a communication link on a commonly-available channel, we investigate the rendezvous problem in CRNs where cognitive users are equipped with multiple radios

Chu, Xiaowen

364

Radio Relics (Type A)  

NASA Astrophysics Data System (ADS)

Galaxy clusters grow by mergers with other clusters and groups. These mergers create shocks within the ICM that accelerate particles which then emit radio waves. We have compiled a sample of clusters with such shocks using radio observations and WHT/INT optical imaging. We propose Chandra observations to determine the conditions under which radio relics form. Modelling of the X-ray data can yield the mass ratio and the impact parameter of the merger. This permits a unique reconstruction of the cluster merger events. Simulations make specific prediction about the location of the relics and the dynamical state of the cluster which can now be tested.

Murray, Stephen

2012-09-01

365

The present state of continental and intercontinental ionospheric radio communications  

NASA Astrophysics Data System (ADS)

Ionospheric characteristics which affect radio wave propagation are discussed, with an emphasis on techniques for using the ionosphere to extend the range of radio links. Interference has been proven highly correlated with the onset of solar disturbances. The ionosphere, however, by bending and reflecting radio signals, is useful for beyond-the-horizon radio links. ELF frequencies permit communication with submerged submarines. HF bands are employed for mobile surface communications around 75 MHz. The VLF bands from 3-30 kHz are applied for long-range links and radionavigation, and with controlled polarization furnish a high SNR. Continuity of broadcasts from earth-earth and earth-satellite depends on constant monitoring of ionospheric conditions and the spectra of the disturbances.

Silleni, S.

366

Comparative and International Corporate Governance  

Microsoft Academic Search

In this article, we examine the state of the art in comparative and international corporate governance by identifying the key research questions, main concepts, and paradigms of explanations of cross?country diversity in corporate governance. First, we discuss the multiple definitions of corporate governance across disciplines and explore how this multi?dimensional nature of corporate governance posses challenges when making cross?national comparisons.

Ruth V. Aguilera; Gregory Jackson

2010-01-01

367

Building and Operating Weather Satellite Ground Stations for High School Science. Teachers Guide.  

ERIC Educational Resources Information Center

Automatic Picture Transmission (APT) images are real-time weather pictures transmitted from satellites on a radio frequency in a video format. Amateur radio enthusiasts and electronic experimenters have for a number of years designed, built, and operated direct readout stations capable of receiving APT photographs. The equipment to receive weather…

Summers, R. Joe; Gotwald, Timothy

368

Corporate Partners with industry to  

E-print Network

these ideas with the Innovation Economy Corporation, we solve one of businesses' greatest challenges: matching to innovate and train engineers to provide solutions to the world's most pressing problems. The Corporate's needs. Amro Albanna, founder and CEO of Innovation Economy Corporation (far right), along with members

369

Corporate sustainability and organizational culture  

Microsoft Academic Search

The concept of corporate sustainability has gained importance in recent years in both organizational theory and practice. While there still exists a lack of clarity on what constitutes corporate sustainability and how to best achieve it, many scholars suggest that the pathway for the adoption of corporate sustainability principles leads via the adoption of a sustainability-oriented organizational culture. In this

Martina K. Linnenluecke; Andrew Griffiths

2010-01-01

370

12 CFR 563.201 - Corporate opportunity.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 false Corporate opportunity. 563.201 Section 563... § 563.201 Corporate opportunity. (a) If you are...take advantage of corporate opportunities belonging to the savings association. (b) A corporate opportunity belongs to a savings...

2010-01-01

371

NEC Corporation Volkswagen Group of America  

E-print Network

. Panasonic Corporation RECRUIT Samsung Electronics Co., Ltd. SingTel TCL Multimedia Toshiba Corporation Jeffrey L. Silverman 1968 Sony Corporation Swatch AG Telmex Toshiba Corporation Philippe Villers MIT MEDIA

372

Science Priorities of the RadioAstron Space VLBI Mission  

NASA Astrophysics Data System (ADS)

The main scientific goal of the RadioAstron Space VLBI mission is study of Active Galactic Nuclei (AGN), Masers and other astronomical objects with unprecedented angular resolution, up to few millionths of an arc-second. The resolution achieved with RadioAstron will allow study the following phenomena and problems: * Central engine of AGN and physical processes near super massive black holes providing an acceleration of cosmic rays size, velocity and shape of emitting region in the core, spectrum, polarization and variability of emitting components; * Cosmological models, dark matter and dark energy by studying dependence of above mentioned AGN's parameters with redshift, and by observing gravitational lensing; * Structure and dynamics of star and planets forming regions in our Galaxy and in AGN by studying maser and Mega maser radio emission; * Neutron (quark?) stars and black holes in our Galaxy, their structure and dynamics by VLBI and measurements of visibility scintillations, proper motions and parallaxes; * Structure and distribution of interstellar and interplanetary plasma by fringe visibility scintillations of pulsars; The RadioAstron mission uses the satellite SPECTR (astrophysical module), developed by Lavochkin Association of Russian Aviation and Space Agency (RASA). This module will be used in several other scientific missions. The total mass of the scientific payload is about 2500 kg, of which the unfolding parabolic 10-m radio astronomy antenna's mass is about 1500 kg, and scientific package holding the receivers, power supply, synthesizers, control units, frequency standards and data transmission radio system. The mass of the whole system (satellite and scientific payload) to be carried into orbit by the powerful "Zenit-2SB"-"Fregat-2CB" launcher is about 5000 kg. The RadioAstron project is an international collaboration between RASA and ground radio telescope facilities around the world.

Langston, Glen; Kardashev, N.; International Space VLBI Collaboration

2006-12-01

373

The Sardinia Radio Telescope  

NASA Astrophysics Data System (ADS)

We present the status of the Sardinia Radio Telescope (SRT) project, a new general purpose, fully steerable 64 m diameter parabolic radio telescope under construction in Sardinia. The instrument is funded by Italian Ministry of University and Research (MIUR), by the Sardinia Regional Government (RAS), and by the Italian Space Agency (ASI), and it is charge to three research structures of the National Institute for Astrophysics (INAF): the Institute of Radio Astronomy of Bologna, the Cagliari Astronomical Observatory (in Sardinia), and the Arcetri Astrophysical Observatory in Florence. The radio telescope has a shaped Gregorian optical configuration with a 8 m diameter secondary mirror and additional Beam-Wave Guide (BWG) mirrors. One of the most challenging feature of SRT is the active surface of the primary reflector which provides good efficiency up to about 100 GHz. This paper reports on the most recent advances of the construction.

D'Amico, Nichi

2011-08-01

374

Structuring Unreliable Radio Networks  

E-print Network

In this paper we study the problem of building a connected dominating set with constant degree (CCDS) in the dual graph radio network model [4,9,10]. This model includes two types of links: reliable, which always deliver ...

Censor-Hillel, Keren

2011-01-01

375

Structuring Unreliable Radio Networks  

E-print Network

In this paper we study the problem of building a connected dominating set with constant degree (CCDS) in the dual graph radio network model. This model includes two types of links: reliable links, which

Censor-Hillel, Keren

2011-12-22

376

BEA Symposium: Research in Radio.  

ERIC Educational Resources Information Center

The seven articles in this journal issue examine trends and topics related to radio and other broadcast media. The articles discuss the following: (1) current trends in radio audience measurement, (2) the policy implications of radio research, (3) a research study of the relationships between age and radio usage, (4) the role of the part-time…

Finney, Robert G., Ed.; Neckowitz, Alan, Ed.

1980-01-01

377

Packet Radio for Library Automation.  

ERIC Educational Resources Information Center

This tutorial on packet radio (communication system using radio and digital packet-switching technology) highlights radio transmission of data, brief history, special considerations in applying packet radio to library online catalogs, technology, defining protocol at physical and network levels, security, geographic coverage, and components. (A…

Brownrigg, Edwin B.; And Others

1984-01-01

378

Early Cambridge radio astronomy  

NASA Astrophysics Data System (ADS)

Radio astronomy started in Cambridge immediately after the hostilities of the World War II have ceased. Martin Ryle was the inspiring leader of a small group that started to develop interferometry techniques at the Cavendish Laboratory. From this development came the numerous Cambridge radio source surveys culminating in the Nobel prize awarded to Martin Ryle for invention of aperture synthesis. The history of this early development is the subject of the present paper.

Smith, F. G.

2007-06-01

379

The Radio JOVE Project  

NASA Astrophysics Data System (ADS)

Radio JOVE is an interactive educational activity which brings the radio sounds of Jupiter and the Sun to students, teachers, and the general public. This is accomplished through the construction of a simple radio telescope kit and the use of a real-time radio observatory on the Internet. Our website (http://radiojove.gsfc.nasa.gov/) will contain science information, instruction manuals, observing guides, and education resources for students and teachers. Our target audience is high school science classes, but subjects can be tailored to college undergraduate physics and astronomy courses or even to middle school science classes. The goals of the project are: 1) Educate people about planetary and solar radio astronomy, space physics, and the scientific method 2) Provide teachers and students with a hands-on radio astronomy exercise as a science curriculum support activity by building and using a simple radio telescope receiver/antenna kit 3) Create the first ever online radio observatory which provides real-time data for those with internet access 4) Allow interactions among participating schools by facilitating exchanges of ideas, data, and observing experiences. Our current funding will allow us to impact 100 schools by partially subsidizing their participation in the program. We expect to expand well beyond this number as publicity and general interest increase. Additional schools are welcome to fully participate, but we will not be able to subsidize their kit purchases. We hope to make a wide impact among the schools by advertising through appropriate newsletters, space grant consortia, the INSPIRE project (http://image.gsfc.nasa.gov/poetry/inspire/), electronic links, and science and education meetings. We would like to acknoledge support from the NASA/GSFC Director's Discretionary Fund, the STScI IDEAS grant program and the NASA/GSFC Space Science Data Operations Office.

Garcia, L.; Thieman, J.; Higgins, C.

1999-09-01

380

Conceptual Background to Radio  

NASA Astrophysics Data System (ADS)

The International Telecommunications Union (ITU) conceives the radio spectrum as primarily a resource for telecommunications. Indeed most applications of radio are for communications and other radio services, particularly the Radio Astronomy Service, are deemed to be `pretend'communication serviceas for spectrum amnagement purposes. The language of Radio Spectrum Management is permeated by the terminology ofcommunications, some derived from the physics of radio and some from aspects of information theory. This contribution touches on all the essential concepts of radiocommunications which the author thinks should be the common mental equipment of the Spectrum Manager. The fundamental capacity of a communication channel is discussed in terms of the degrees of freedom and bandwidth of a signal, and the signal to noise ratio. It is emphasized that an information bearing signal is inherently unpredictable, and must, at some level, be discontinuous. This has important consequences for the form of its power spectrum. The effect of inserting filters is discussed particularly with regard to constant amplitude signals and, in the context of non-linear power amplifiers, the phenomenon of`sideband recovery'. All the common generic forms of modulation are discussed including the very different case of `no-modulation' which applies in all forms of passive remote sensing. Whilst all are agreed that the radio spectrum should be used `efficiently', there is no quantitative measure of spectral efficiency which embraces all relevant aspects of spectral usage. These various aspects are dicussed. Finally a brief outline of some aspects of antennae are reviewed. It is pointed out that the recent introduction of so-called `active antennnae', which have properties unlike traditional passive antennae, has confused the interpretation of those ITU Radio Regulations which refer to antennae.

Ponsonby, J. E. B.

2004-06-01

381

Satellite broadcasting: Requirements for the receiving antenna  

NASA Astrophysics Data System (ADS)

The receiving antenna plays a significant part in the reception of television signals broadcast from a satellite in so-called Direct Broadcasting by Satellite (DBS). The performance of the antenna must be sufficiently good to ensure that signals are received without suffering adverse effects of noise or interference. A hypothetical receiver specification was used during the planning of satellite broadcasting at the World Administrative Radio Conference in 1977 (WARC-77), but while this is in general sufficient it may not always be necessary. Furthermore, the different trade-offs involved in the antenna designs (including flat-plate types) may mean that the same result can most effectively be obtained with a very different specification. The various requirements are explained, and examples are given for incomplete or lower-power use of the WARC-77 allocations. It provides a useful background to related research reports which describe work on flat-plate antennas.

Stott, J. H.

382

Observations of the 557 GHz Line of Water in Comet C/2001 A2 (LINEAR) with the Odin Satellite  

NASA Astrophysics Data System (ADS)

Odin is a small astronomical/aeronomical satellite which was launched in February 2001. One of its capacities is the observation of the 110--101 line of water at 557 GHz with a high spectral resolution (corresponding to 80 m s-1) and a spatial resolution of 2 arcmin. During its commissioning phase, Odin observed comet C/2001 A2 (LINEAR) several times in April and from June 20 until July 9, 2001. From a preliminary analysis, 10 x 10 arcmin mapping of the 557 GHz water line on July 1.5--2.4 UTC shows that the H2O coma is elongated along the comet-Sun line. The line shape is asymmetric, which may be attributed to self-absorption in the foreground of the coma. The line width indicates a H2O outflow velocity of 0.7 km s-1. The integrated line intensity peaks at 12 K km s-1 on the main-beam brightness temperature scale. The corresponding water production rate is estimated at 3.8 x 1028 molecules s-1 for July 1.7--2.0. The outflow velocity and water production rate agree with independent observations of the 18 cm lines of OH at the Nançay radio telescope. Odin (http://www.snsb.se/odin/odin.html) is a Swedish-led satellite project funded jointly by SNSB (Sweden), CSA (Canada), Tekes (Finland) and CNES (France), Swedish Space Corporation being the prime contractor.

Biver, N.; Lecacheux, A.; Crovisier, J.; Bockelée-Morvan, D.; Rickman, H.; Lagerkvist, C. I.; Winnberg, A.; ODIN Team

2001-11-01

383

Feasibility of microminiature satellites  

NASA Astrophysics Data System (ADS)

A conceptual study is conducted on technical problems and system design techniques to accomplish higher performance microminiature satellites by smaller systems. Applications of microminiature satellite technology to practical satellite mission are mentioned. Concepts of microminiature satellites, measures to miniaturize satellites, and micro-miniaturization technologies for communication and data processing, electric solar power paddle, attitude and orbit control, structure, thermal control, propulsion, and instrumentation systems are outlined. Examples of miniaturizing satellite missions such as planet exploration, low-altitude communication networks, space positioning system, low-altitude earth observation mission, clustered satellites, tethered satellites, and timely observation are described. Satellite miniaturizing technology can also be used to launch systems by lasers, and superconductive linear catapults (space escalator). It is pointed out that keys to promote satellite miniaturization are electronics, precision machining, raw material, electric power source technologies, and system design technology to integrate those technologies.

Imai, Ryouichi

1991-07-01

384

Industrial Analytics Corporation  

SciTech Connect

The lost foam casting process is sensitive to the properties of the EPS patterns used for the casting operation. In this project Industrial Analytics Corporation (IAC) has developed a new low voltage x-ray instrument for x-ray radiography of very low mass EPS patterns. IAC has also developed a transmitted visible light method for characterizing the properties of EPS patterns. The systems developed are also applicable to other low density materials including graphite foams.

Industrial Analytics Corporation

2004-01-30

385

Educational Broadcasting Corporation  

NSF Publications Database

16 Schedule B-1 EDUCATIONAL BROADCASTING CORPORATION Indirect Cost Calculation For the year ended June 30, 2000 ($ In Thousands) Auditors' Schedule Proposed Adjustments and Allowable Reference Costs Eliminations Costs Direct cost B-1a $ XXXXX X XX XXXXX Indirect cost pool: Executive and administrative services B-1b $ XXXXX X (XX) $ XXXXX Technical support services B-1c XXXX XXXX Program staff administration B-1d XXXX X XXXX Total indirect costs

386

Radio magazines and the development of broadcasting: Radio broadcast and radio news, 1922–1930  

Microsoft Academic Search

This paper explores the development of two early popular radio magazines: Radio Broadcast and Radio News. The two magazines developed along with the emerging broadcast industry during the 1920s. The historical review and content analysis of the magazines revealed that they enjoyed a great deal of success in the early 1920s by appealing to amateur radio enthusiasts. Both started as

Michael Brown

1998-01-01

387

Extragalactic Radio Jets and Intergalactic Medium 2  

NASA Technical Reports Server (NTRS)

During the mid 1990s, the ROSAT satellite provided the highest resolution X-ray imaging, with useful X-ray spectroscopy, and excellent sensitivity. ROSAT"s PSPC and HRI instruments gave us our first high-quality data on the AGN phenomenon in nearby galaxies - the central theme of this research project. Initially this project concentrated on separating the AGN-related component of the X-ray emission from thermal radiation from the surrounding atmospheres in radio galaxies. There was ample reason to believe that this separation would be possible, although earlier work had taken the view that the X-ray emission from radio galaxies is either wholly AGN-related (and hence of sub-arcsec scale), or wholly from the galaxy and cluster atmospheres (and hence of scales - 10 arcsec or more in the low-redshift radio galaxies that we chose to study). First with the PSPC, and then with the HRI, we proved that a wide range of AGN core X ray emissivities could be found, and that the generic radio galaxy produces both AGN-related and atmosphere-related X-radiation. We demonstrated that there is a close relationship between the core X-ray power and the core radio power, and found instances in which the hot atmospheres of the galaxies must be participating in cooling flows, and other cases where those atmospheres are relatively stable. In some cases, there is a clear active relationship between the extended radio emission and the X-ray atmospheres: thus in NGC 326, we interpret the distorted radio structure as evidence of buoyancy as the radio plasma rises through the cluster atmosphere. In 3C 449, we can see that the radio plasma is displacing the X-ray emitting gas. In a further case (NGC 1265), we hoped that the motion of a radio galaxy through a cluster atmosphere would be apparent though the wake that it might establish - unfortunately, other structure in the atmosphere of the Perseus cluster tends to dominate our X-ray image, and no useful limits could be placed on the strength of the wake. In the light of so-called "unified" models of AGN, it is expected that the low-power radio galaxies studied under these programmes are the unbeamed counterparts of BL Lac objects. Accordingly, we predicted that BL Lac objects, as a class, should show X-ray halos from atmospheres similar to those associated with radio galaxies. The difficulty with studying this is that BL Lac objects tend to be X-ray bright, and the halos then vanish under the wings of the point response function. We found a BL Lac with less of a dynamic range problem, mapped it with the ROSAT HRI, and duly found an atmosphere (Hardcastle et al. 1999). Unfortunately for unification models, this atmosphere is exceptionally dense, so that it must be participating in an intense cooling flow. The implications of this for unification models are far from clear, and further work is under way.

Birkinshaw, Mark

2000-01-01

388

Integrated Satellite Control in REIMEI (INDEX) Satellite  

NASA Astrophysics Data System (ADS)

REIMEI/INDEX (INnovative-technology Demonstration EXperiment) is a 70kg class small satellite which the Institute of Space and Astronautical Science, Japan Exploration Agency, ISAS/JAXA, has developed for observation of auroral small-scale dynamics as well as demonstration of advanced satellite technologies. An important engineering mission of REIMEI is integrated satellite control using commercial RISC CPUs with a triple voting system in order to ensure fault-tolerance against radiation hazards. Software modules concerning every satellite function, such as attitude control, data handling, and mission applications, work cooperatively so that highly sophisticated satellite control can be performed. In this paper, after a concept of the integrated satellite control is introduced, the Integrated Controller Unit (ICU) is described in detail. Also unique topics in developing the integrated control system are shown.

Fukuda, Seisuke; Mizuno, Takahide; Sakai, Shin-Ichiro; Fukushima, Yousuke; Saito, Hirobumi

389

Enhancing the Security of Corporate Wi-Fi Networks Using DAIR  

Microsoft Academic Search

We present a framework for monitoring enterprise wireless networks using desktop infrastructure. The framework is called DAIR, which is short for Dense Array of Inexpensive Radios. We demonstrate that the DAIR framework is useful for detecting rogue wireless devices (e.g., access points) attached to corporate networks, as well as for detecting Denial of Service attacks on Wi-Fi networks. Prior proposals

Paramvir Bahl; Ranveer Chandra; Jitendra Padhye; Alec Wolman

2006-01-01

390

Satellite Communications for U.S. Schools; A Proposed Public Service Offering by Private Business.  

ERIC Educational Resources Information Center

The Federal Communications Commission has asked that companies seeking authorization to construct and operate communications satellite facilities for multi-purpose commercial uses in the United States give consideration to the communications needs of schools. In response to this request, MCI Lockheed Satellite Corporation proposes a low-cost…

Krause, Lloyd I.

391

"SpaceCam": Legal Issues in the Use of Remote-Sensing Satellites for News Gathering.  

ERIC Educational Resources Information Center

News media representatives foresee a growing use of remote-sensing satellites to gather data, including data that could be used to check government claims about military and other activities occurring anywhere on the planet. The satellite technology is developing rapidly, and several nations and private corporations are involved in separate…

Smith, William E.

392

Korea's first satellite for satellite laser ranging  

Microsoft Academic Search

Science Technology Satellite-2 (STSAT-2) has been developed since October 2002 as a sequel mission to KAISTSAT-4 (STSAT-1). STSAT-2 is scheduled to be launched into an ellipsoidal orbit of 300km×1500km in December 2005 by the first Korea Satellite Launch Vehicle KSLV-1. STSAT-2 has two payloads: a Lyman-? imaging solar telescope and a laser reflector array (LRA) for satellite laser ranging. The

Jun Ho Lee; Seung Bum Kim; Kyung Hee Kim; Sang Hyun Lee; Yong Jo Im; Yang Fumin; Chen Wanzhen

2005-01-01

393

Korea's first satellite for satellite laser ranging  

Microsoft Academic Search

Science Technology Satellite-2 (STSAT-2) has been developed since October 2002 as a sequel mission to KAISTSAT-4 (STSAT-1). STSAT-2 is scheduled to be launched into an ellipsoidal orbit of 300km×1500km in December 2005 by the first Korea Satellite Launch Vehicle KSLV-1. STSAT-2 has two payloads: a Lyman-alpha imaging solar telescope and a laser reflector array (LRA) for satellite laser ranging. The

Jun Ho Lee; Seung Bum Kim; Kyung Hee Kim; Sang Hyun Lee; Yong Jo Im; Yang Fumin; Chen Wanzhen

2005-01-01

394

Quad-Tree Visual-Calculus Analysis of Satellite Coverage  

NASA Technical Reports Server (NTRS)

An improved method of analysis of coverage of areas of the Earth by a constellation of radio-communication or scientific-observation satellites has been developed. This method is intended to supplant an older method in which the global-coverage-analysis problem is solved from a ground-to-satellite perspective. The present method provides for rapid and efficient analysis. This method is derived from a satellite-to-ground perspective and involves a unique combination of two techniques for multiresolution representation of map features on the surface of a sphere.

Lo, Martin W.; Hockney, George; Kwan, Bruce

2003-01-01

395

Developments in land mobile satellite service in Europe  

NASA Technical Reports Server (NTRS)

The evolution of land mobile radio has reached a stage to benefit from satellite communications. The provision of a service on a pan-European basis makes the use of satellites a viable proposition. The paper describes the European position on both system and space segment aspects of the land mobile satellite service. Also, some of the functions of the European institutions, such as the European Telecommunications Standards Institute (ETSI), the Conference of European Postal and Telecommunications Administrations (CEPT), and the Commission of European Communities (CEC), in establishing these services are identified.

Jayasuriya, D. A. R.

1990-01-01

396

Measurement and analysis of Satellite Digital Audio signals in Rayleigh fading scenarios  

Microsoft Academic Search

Satellite digital audio radio service (SDARS) has been introduced in North America since 2001. Performance degradation occurs mainly due to the weak satellite signals in rural environment particular underneath dense foliage. Antenna diversity technique at the receiver is a suitable approach in order to overcome the problem of performance degradation. In order to analyze and optimize an antenna diversity system

D. J. Muller; L. M. Reiter; D. E. Barie; S. M. Lindenmeier

2008-01-01

397

Photogrammetric satellite service prediction - Correlation of RF measurements and image data  

Microsoft Academic Search

This paper addresses the image-based characteri- zation of the land mobile satellite channel. In a measurement campaign, the signal power levels of the Satellite Digital Audio Radio Services (SDARS) in the U.S. were recorded. In parallel, a fisheye camera on the roof of the measurement van continuously acquired images of the upper hemisphere. Using time, location and heading information from

Alexander Ihlow; Daniel Arndt; Felix Topf; Christoph Rothaug; Thomas Wittenberg; Albert Heuberger

2011-01-01

398

Submicrosecond comparisons of time standards with the Navigation Technology Satellites (NTS)  

Microsoft Academic Search

During May through September 1978 a six nation cooperative experiment was performed to intercompare time standards of major laboratories at the submicrosecond level using NTS satellites. NTS time transfer receivers, which were developed for use with the NTS series of satellites, were installed at the Division of National Mapping (DNM), Australia; in Japan at the Radio Research Laboratories (RRL) and

J. Buisson; T. McCaskill; J. Oaks; D. Lynch; S. C. Wardrip

1980-01-01

399

Estimating lightning current moment waveforms from satellite optical measurements  

E-print Network

Estimating lightning current moment waveforms from satellite optical measurements Toru Adachi,1 and Duke magnetometer observed clear optical and radio signatures of 12 sprite- producing lightning events to remotely measure lightning current moment, which is critical for understanding the production of sprites

California at Berkeley, University of

400

Usage and protection of the earth exploration satellite service  

Microsoft Academic Search

Earth observations by microwave radiometers are typically performed at frequencies allocated for passive use to the Earth Exploration Satellite Service (EESS). Many of these allocations are shared with the Radio Astronomy Service (RAS) and are also often shared with generally compatible active services. The problem of RFI in spaceborne microwave radiometer data has been known since 1978 when it was

Jeffrey Piepmeier

2008-01-01

401

Thermospheric studies using satellites AEROS A and B  

Microsoft Academic Search

Atmospheric drag was analyzed in order to determine the atmospheric total density at perigee by the orbital drag technique. The principle of this technique, reduction of radio interferometer and radar observations, and the results of an orbit improvement procedure are presented. The aerodynamic drag coefficient of a cylindrical spin stabilized satellite was determined for all angles of attack. Measured values

M. Roemer; W. Framke; H. J. Beese; M. Jung; E. Richter; O. Senzlober

1981-01-01

402

Educational Radio. Information Bulletin 21-B.  

ERIC Educational Resources Information Center

The term "Educational Radio" includes all radio stations licensed for noncommercial operation. A history of educational radio begins with the first domestic law for control of radio in general, The Radio Act of 1912. Federal Communication Commission (FCC) regulations pertaining to educational radio or "public radio" deal with channel assignments,…

Federal Communications Commission, Washington, DC.

403

Monolithic Multichannel GSa\\/s Transient Waveform Recorder for Measuring Radio Emissions from High Energy Particle Cascades  

Microsoft Academic Search

A number of particle astrophysics initiatives to exploit radio emission from high energy particle cascades require high- frequency sampling of antenna array signals. Nyquist-limited sampling of GHz frequency radio signals for an antenna array may be accomplished by commercially available test units. However, these technologies are incompatible with the size, power and cost constraints of long-duration balloon or satellite flight.

Gary S. Varner; Peter Gorham; Jing Cao

404

Building corporate associations: Consumer attributions for corporate socially responsible programs  

Microsoft Academic Search

Corporate social responsibility (CSR) is often used as a key criterion in gauging corporate reputation. This research examined\\u000a the influence of consumers’ attributions on corporate outcomes in response to CSR. Researchers and managers have considered\\u000a consumers’ beliefs about CSR initiatives to be simplistic, serving either economic ends or reflecting sincere social concerns.\\u000a The results of two studies established that consumers’

Pam Scholder Ellen; Deborah J. Webb; Lois A. Mohr

2006-01-01

405

What are Satellites?  

NSDL National Science Digital Library

In this activity, students differentiate between natural satellites and artificial satellites, and are challenged to create a model of an artificial satellite, including calculating the amount of energy required to power the satellite and the size of the solar array required to generate that power. Student worksheets, answer sheet, illustrations of satellites, teacher tips and Web links are included. This is Lesson 2 in What are Satellites, part of IMAGERS, Interactive Media Adventures for Grade School Education using Remote Sensing. The website provides hands-on activities in the classroom supporting the science content in two interactive media books, The Adventures of Echo the Bat and Amelia the Pigeon.

406

An Introduction to Radio Astronomy  

NASA Astrophysics Data System (ADS)

Preface; 1. Introduction; 2. The nature of the radio signal; 3. Signals, noise, radiometers and spectrometers; 4. Single-aperture radio telescopes; 5. The two-element interferometer; 6. Aperture synthesis; 7. Radiation, propagation and absorption of radio waves; 8. The local universe; 9. The interstellar medium; 10. Galactic dynamics; 11. Stars; 12. Pulsars; 13. Radio galaxies and quasars; 14. Cosmology fundamentals; 15. The angular structure of the CMB; 16. Cosmology: discrete radio sources and gravitational lensing; 17. The future of radio astronomy; Appendixes; References; Index.

Burke, Bernard F.; Graham-Smith, Francis

2014-02-01

407

New American Radio  

NSDL National Science Digital Library

It's quite unusual that a long-defunct radio program would garner a new website, but this is the case with the New American Radio (NAR) show. During its 10-year run, NAR commissioned and distributed over 300 original works, including conceptual new drama works, language explorations, sonic meditations, and works that "pioneer new dimensions in acoustic space." On the site's homepage, visitors can peruse a list of full-length works, excerpts, and even a set of meditative essays on the creative process. A good work to start with here is "O Little Town of East New York" by Shelley Hirsch. It's a compelling autobiographical "docu-musical" about growing up in this diverse neighborhood in the 1960s. The site could be used by any number of students studying communication, drama, theater, radio production, and related subjects.

408

Satellite Home Tutorials vs. Satellite Classroom Tutorials.  

ERIC Educational Resources Information Center

In this study, students who registered for a course at the Open University of Israel could choose the tutorial method they preferred: group face-to-face tutorials with a local tutor in their residential vicinity; tutorials via satellite broadcasting to groups of students around the country; or getting the same satellite tutorial at home on the…

Beyth-Marom, Ruth; Yafe, Edna; Privman, Meira; Harpaz, Hamutal Razy

409

Error-free command link for sounding rockets and satellites  

NASA Astrophysics Data System (ADS)

The Swedish Space Corporation has developed an error-free command uplink system for sounding rockets and satellites. The system architecture allows for safe command transmission without any time penalties during normal operation, and it recovers fast and wholly transparent from transmission errors without any user or operator interaction. The implementation is partly based on the CCSDS recommendations regarding satellite uplinks, but modified to better suit the PCM-based downlink systems, normally used for sounding rockets systems and small satellites. The system has proven extremely efficient and reliable during several small- and micro satellite projects such as ODIN, TeleFoton and Astrid-2. This paper presents the system architecture and shows the details for the implementations used in the Swedish scientific satellites ODIN and Astrid-2.

Ringstrand, Hans

2003-08-01

410

International Finance Corporation  

NSDL National Science Digital Library

As a part of the World Bank, the stated vision of the International Finance Corporation (IFC) is "that poor people have the opportunity to escape poverty and to improve their lives." To whit, the IFC works to promote open and competitive markets in developing countries, generate productive jobs and deliver basic services, among other things. First-time visitors will find that the layout of the site is visually stimulating and quite user-friendly. Visitors can use the embedded search engine to look for specific materials of interest.

411

Taking DSM to corporate management  

SciTech Connect

This article examines the process leading to a successful power use management program for corporations. Any good energy program starts with a corporate energy policy defining the program and its expectations, including directions to managers and individual employees. Once the program is defined, it must be taken to top management. It's imperative that they buy into the program, as corporate-wide programs that begin at lower levels never really catch on. With top-management support, you're more likely to change the corporate culture, or the behavior of employees at all levels in the corporation. When the corporate culture changes, attitudes will soon follow and energy management can then evolve from an afterthought to a forethought.

Musur, A. (Abbot Labs., North Chicago, IL (United States))

1993-01-01

412

Radio Interference at the Molonglo Radio Observatory.  

NASA Astrophysics Data System (ADS)

In conjunction with the local Spectrum Management Agency, field trials have been carried out to determine the susceptibility of the Molonglo Observatory Synthesis Telescope (MOST) to interference from terrestrial transmitters. The MOST operates at a frequency of 843 MHz with a 3 dB bandwidth of 3 MHz. The entire band from 825 to 845 MHz has been allocated for mobile telephone use and is soon to be sold to commercial users. Even though 843 MHz is not an internationally recognised radio astronomy frequency, since the MOST began operation in 1980, the band has been locally respected after consultation with Telecom Australia. Normal operation of the MOST requires 12 hours observation to synthesise an image of ~1-5 sq. degrees of sky. In-band interference with irradiance exceeding -172 dBWm^-2 (which confirms our theoretical predictions) causes noticable degradation of MOST images, although occasional bursts stronger than that are tolerable. The damage to MOST images caused by interference depends on the type of modulation and duration of the transmission and the type of observation. The telescope has recently been funded to carry out a deep radio survey of the southern sky. The viability of this survey is now being seriously threatened.

Davidson, G.; Campbell-Wilson, D.; Large, M. I.

413

eRadio : empowerment through community Web radio  

E-print Network

The eRadio project proposes to be an effective aid to increase interaction and reduce alienation among the members of dispersed communities by using a holistic approach to participatory and interactive web radio-production, ...

Gomez-Monroy, Carla, 1977-

2004-01-01

414

Remote Radio Sounding Science for JIMO  

NASA Technical Reports Server (NTRS)

Radio sounding of the Earth's top side ionosphere and magnetosphere is a proven technique from geospace missions such as the International Satellites for Ionospheric Studies (ISIS) and the Imager for Magnetopause-to-Aurora Global Exploration (IMAGE). Application of this technique to the Jupiter Icy Moons Orbiter (JIMO) mission will provide unique remote sensing observations of the plasma and magnetic field environments, and the subsurface conductivities, of Europa, Ganymede, and Callisto. Spatial structures of ionospheric plasma above the moon surfaces vary in response to magnetic field perturbations from (1) magnetospheric plasma flows, (2) ionospheric currents from ionization of sputtered surface material, and (3) induced electric currents in salty subsurface oceans. Radio sounding at 3 kHz to 10 MHz can provide globally-determined electron densities necessary for the extraction of the oceanic current signals and supplements in-situ plasma and magnetic field measurements. Subsurface variations in conductivity, can be investigated by radio sounding from 10 MHz to 40 MHz allowing the determination of the presence of dense and solid-liquid phase boundaries associated with oceans and related structures in overlying ice crusts.

Green, J. L.; Reinisch, B. W.; Song, P.; Fung, S. F.; Benson, R. F.; Taylor, W. W.; Cooper, J. F.; Garcia, L.; Gallagher, D.

2003-01-01

415

Radio Observations of Supernovae  

E-print Network

Study of radio supernovae over the past 25 years includes two dozen detected objects and more than 100 upper limits. From this work it is possible to identify classes of radio properties, demonstrate conformance to and deviations from existing models, estimate the density and structure of the circumstellar material and, by inference, the evolution of the presupernova stellar wind. It is also possible to detect ionized hydrogen along the line of sight, to demonstrate binary properties of the stellar system, to detect clumpiness of the circumstellar material, and to put useful constraints on the progenitors of undetected Type Ia supernovae.

Panagia, N; Van Dyk, S D; Sramek, R A; Stockdale, C J; Panagia, Nino; Weiler, Kurt W.; Dyk, Schuyler D. Van; Sramek, Richard A.; Stockdale, Christopher J.

2007-01-01

416

Radio Observations of Supernovae  

E-print Network

Study of radio supernovae over the past 25 years includes two dozen detected objects and more than 100 upper limits. From this work it is possible to identify classes of radio properties, demonstrate conformance to and deviations from existing models, estimate the density and structure of the circumstellar material and, by inference, the evolution of the presupernova stellar wind. It is also possible to detect ionized hydrogen along the line of sight, to demonstrate binary properties of the stellar system, to detect clumpiness of the circumstellar material, and to put useful constraints on the progenitors of undetected Type Ia supernovae.

Nino Panagia; Kurt W. Weiler; Schuyler D. Van Dyk; Richard A. Sramek; Christopher J. Stockdale

2007-03-15

417

Tax aspects of collapsible corporations  

E-print Network

sible Coi ration Section 341 (b) defines the collapsible corporation as one formed or availed of principally for the manufacture, con- struction, or production of property or the purchase of property which (in the hands of the corporation... or liquidation occurs before there has been a realization of substantial income. However, since the statute is vague, one assumes a heavy responsibility in trying to establish that it has any one meaning. Colla sible Pro ert Not all property of a corporation...

Lehmann, Herman August

2012-06-07

418

New systems for space based monitoring of ionospheric irregularities and radio wave scintillations  

NASA Astrophysics Data System (ADS)

The ionosphere has long been known to be the primary source of amplitude and phase fluctuations for VHF, UHF, and L-Band radio waves. Monitoring ionospheric irregularities that affect radio propagation is currently being implemented using in situ, radio and optical sensors on satellites in low-earth orbit (LEO). The remote sensing instruments provide observations of extreme ultraviolet (EUV) emissions or total electron content (TEC) to reconstruct images of electron densities. The GPS MET satellite has provided a global description of the ionosphere using GPS occultation from space. The ARGOS satellite launched in February 1999 has produced new images of the ionosphere using both EUV limb scanning and computerized ionospheric tomography (CIT) techniques. Recent measurements from the ARGOS satellite have provided data for improved modeling of both global scale and small-scale structures in the ionosphere. Future satellite sensors will be launched with EUV limb scanners, GPS occultation receivers, radio beacons for CIT, and beacon receivers for global mapping of ionospheric scintillations. These satellites will be placed in a variety of orbit inclinations to cover the equatorial, mid-latitude, and polar ionospheres.

Bernhardt, P. A.; Huba, J. D.; Selcher, C. A.; Dymond, K. F.; Carruthers, G. R.; Bust, G.; Rocken, C.; Beach, T. L.

419

Local oscillator distribution using a geostationary satellite  

NASA Technical Reports Server (NTRS)

A satellite communication system suitable for distribution of local oscillator reference signals for a widely spaced microwave array has been developed and tested experimentally. The system uses a round-trip correction method of the satellite This experiment was carried out using Telstar-5, a commercial Ku-band geostationary satellite. For this initial experiment, both earth stations were located at the same site to facilitate direct comparison of the received signals. The local oscillator reference frequency was chosen to be 300MHz and was sent as the difference between two Ku-band tones. The residual error after applying the round trip correction has been measured to be better than 3psec for integration times ranging from 1 to 2000 seconds. For integration times greater then 500 seconds, the system outperforms a pair of hydrogen masers with the limitation believed to be ground-based equipment phase stability. The idea of distributing local oscillators using a geostationary satellite is not new; several researchers experimented with this technique in the eighties, but the achieved accuracy was 3 to 100 times worse than the present results. Since substantially and the performance of various components has improved. An important factor is the leasing of small amounts of satellite communication bandwidth. We lease three 100kHz bands at approximately one hundredth the cost of a full 36 MHz transponder. Further tests of the system using terminal separated by large distances and comparison tests with two hydrogen masers and radio interferometry is needed.

Bardin, Joseph; Weinreb, Sander; Bagri, Durga

2004-01-01

420

OECD Principles of Corporate Governance  

NSDL National Science Digital Library

The "Organisation for Economic Co-operation and Development Principles of Corporate Governance" sets out a structure for directing and controlling corporate businesses. This document (html or .pdf) consists of five sections detailing the principles: "The rights of shareholders," "The equitable treatment of shareholders," "The role of stakeholders in corporate governance," "Disclosure and transparency," and "The responsibilities of the board," as well as annotations for each of the sections. Be sure to visit the OECD Principles of Corporate Governance Q&A page, linked at the top of the page.

421

Stereo Measurements from Satellites  

NASA Technical Reports Server (NTRS)

The papers in this presentation include: 1) 'Stereographic Observations from Geosynchronous Satellites: An Important New Tool for the Atmospheric Sciences'; 2) 'Thunderstorm Cloud Top Ascent Rates Determined from Stereoscopic Satellite Observations'; 3) 'Artificial Stereo Presentation of Meteorological Data Fields'.

Adler, R.

1982-01-01

422

Radar Calibration Test Satellite  

Microsoft Academic Search

A satellite has been designed for application to radar calibration. Electromagnetic and mechanical characteristics of the satellite and their influence on the selection of shape and other parameters are discussed. Theoretical and experimental scattering data are included.

L. J. Kaplan; J. F. A. Ormsby; EVERT N. FOWLE; KENT R. JOHNSON; Richard T. Bates; S. H. Bickel

1969-01-01

423

Hurricane Katrina Satellite Imagery  

NSDL National Science Digital Library

This page provides access to a good number of satellite images of Hurricane Katrina taken by polar orbiting and geostationary satellites operated by NOAA. High resolution images are available on the site.

National Environmental Satellite, Data, and Information Service

424

Evolutionary algorithms for radio resource management in cognitive radio network  

Microsoft Academic Search

Cognitive radio (CR) technology employing dynamic spectrum access (DSA) improves spectrum utilization by exploiting its unused portions and provides a solution to the apparent spectrum scarcity problem. In this paper we present binary particle swarm optimization (BPSO) and genetic algorithm (GA) for radio resource management (RRM) in OFDMA-based cognitive radio network (CRN). The simulation results show that BPSO-based RRM performs

Muhammad Waheed; Anni Cai

2009-01-01

425

Corporate citizenship: Statoil.  

PubMed

Open markets alone do not guarantee equitable and sustainable development. Income disparities are growing both within and between countries to the extent that the marginalization of the poor has become a key challenge of globalization. To meet this challenge, the global community must address the governance gap between global finance/economics and local or national politics in world affairs. This article discusses how globalization is shaping Statoil's approach to corporate citizenship. The Norwegian firm, with 17,000 workers in some 25 countries, is one of the major net sellers of crude oil and supplies Europe with natural gas. Statoil maintains that corporations can contribute to global governance by conducting business in a manner that is ethical, economically viable, environmentally sound, and socially responsible. This contribution can be achieved through development partnerships with national governments, multilateral institutions, and nongovernmental organizations. Norway's Statoil ASA is one of the world's largest net sellers of crude oil and a major supplier of natural gas to Europe. It is the leading Scandinavian retailer of petroleum and other oil products. Statoil employs approximately 17,000 workers and operates in 25 countries. PMID:17208716

Fjell, Olav

2003-01-01

426

Business Development Corporation, Inc.  

SciTech Connect

Business Development Corporation, Inc., is a company specializing in opportunity seeking and business development activities in the {open_quotes}new{close_quotes} post communist Central and Eastern Europe, with particular emphasis on the Republics of Poland and Slovakia. The company currently focuses its expertise on strategic investing and business development between Central Europe and the United States of America. In Poland and Slovakia, the company specializes in developing large scale energy and environmental {open_quotes}infrastructure{close_quotes} development projects on the federal, state, and local level. In addition, the company assists large state owned industries in the transformation and privatization process. Business Development Corporation has assisted and continues to assist in projects of national importance. The staff of experts advise numerous large Polish and Slovak companies, most owned or in the process of privatization, on matters of restructuring, finance, capital structure, strategic parternships or investors, mergers, acquisitions and joint ventures with U.S. based firms. The company also assists and advises on a variety of environmental and energy matters in the public and private sector.

Jasek, S.

1995-12-31

427

Radio Frequency Identification Technology and the Risk Society: A Preliminary Review and Critique for Justice Studies  

Microsoft Academic Search

Radio Frequency Identification (RFID) technology promises to revolutionize the way in which citizens interact with society, guaranteeing heightened security and increased protection speculatively critiques the soundness of this logic, especially mindful of the risk society thesis. Relevant historical background on RFID is provided, several notable applications in the corporate and governmental sectors are delineated, and the ethical and

Brian Sellers

2009-01-01

428

Educational Radio. We Can Learn from Other Countries' Experience. A Literature Survey. Internal Report.  

ERIC Educational Resources Information Center

An internal report of Educational Radio and Television (ERTV), the South African Broadcasting Corporation, this literature survey is designed to provide a basis for specific practical, local research in areas such as curriculum analysis, target audience research, research on listening habits, availability of the medium, cost analysis, and…

Duby, Aliza

429

The First Wave: The Beginnings of Radio in Canadian Distance Education  

ERIC Educational Resources Information Center

This article describes one of the first developments and deployment of radio for distance learning and education in Canada, beginning in the early 1920s. Anticipating a recent initiative of public-private partnerships, the impetus, infrastructure, and initial programs were provided by a large corporation. Description of the system, its purpose,…

Buck, George H.

2006-01-01

430

Talk Radio as Interpersonal Communication.  

ERIC Educational Resources Information Center

Examines whether talk radio serves different purposes for listeners who phone in, compared to those who do not. Finds that talk radio provides callers with an accessible and nonthreatening alternative to interpersonal communication. (MS)

Armstrong, Cameron B.; Rubin, Alan M.

1989-01-01

431

Speakeasy: the military software radio  

Microsoft Academic Search

The Speakeasy Phase II radio will use programmable processing to emulate more than 15 existing military radios. Speakeasy is a challenge, even with recent advancements in DSP technologies. The benefits, however, make the challenge highly worthwhile

R. I. Lackey; D. W. Upmal

1995-01-01

432

Multinational Corporations vs. Domestic Corporations: Financial Performance and Characteristics  

Microsoft Academic Search

The analysis in this paper is composed of two segments. First, the financial performance of a sample of multinational corporations (MNCs) is compared with that derived for a control group of domestic corporations (DMCs) using market-based performance measures. Then, the paper presents a comparison of selected financial characteristics of the firms in the two groups. The results suggest the DMCs

Allen Michel; Israel Shaked

1986-01-01

433

The Manufacture of Corporate Social Responsibility: Constructing Corporate Sensibility  

Microsoft Academic Search

This paper develops a framework for differentiating between mere image and substance in corporate claims to social responsibility. The paper begins by drawing upon the work of Levinas to explore the nature of responsibility and ethical sensibility. It then explores four versions of corporate social responsibility (CSR): the conditions under which CSR is squeezed out by the dominance of financial

John Roberts

2003-01-01

434

Corporate reputation versus corporate branding: the realist debate  

Microsoft Academic Search

Studies in the fields of marketing and corporate identity are at a crossroads. Changes in the structure of organisations and their operating environments have led to the emergence of the concept of corporate branding and possibly even the development of a new domain of management science. This paper traces the development of brand thinking from both a marketing (customer market)

David Bickerton

2000-01-01

435

India's earth resources satellite  

Microsoft Academic Search

The Satellite for Earth Observation (SEO), the second Indian satellite launched by the USSR in February 1979, for studying cultivated land, forests, rivers, snow and wetland in coastal areas is described. Consideration is given to its design and to two slow-scan TV cameras and a passive microwave radiometer, forming the main payload of SEO. The satellite is a 26 faceted

H. P. Mama

1979-01-01

436

Radio's regulatory roadblocks  

Microsoft Academic Search

Great news! Your team has come up with a new radio technology - one that may have the same impact as Wi-Fi or Bluetooth. Management loves it, funding is in place, patent applications are ' filed, production is lined up, and marketing is ready to go. This will be huge. Or maybe not. Your invention could be illegal in the

M. Lazarus

2009-01-01

437

Japanese Radio Exercises. Revised.  

ERIC Educational Resources Information Center

This unit focuses on Japanese radio exercises which became popular in Japan just after World War II and are still used among students and workers in companies to help raise morale and form group unity. The exercises reflect the general role of exercise in Japanese culture--to serve as a symbol of unity and cooperation among the Japanese, as well…

Young, Jocelyn

438

RECONFIGURABILITY FACILITATING COMPOSITE RADIO  

Microsoft Academic Search

The key objective of End-to-End Reconfigurability (E²R) is to devise, develop and trial architectural design of reconfigurable devices and supporting system functions to offer an expanded set of operational choices to the different actors of the value chain in the context of heterogeneous mobile radio systems.

Jijun Luo; Klaus Moessner; David Grandblaise; Karim El-Khazen; Didier Bourse; Eiman Mohyeldin; Panagiotis Demestichas

439

Radio and Biography  

Microsoft Academic Search

Scholars and authors sometimes lament that broadcast versions of written biographies are inaccurate or simplistic. This essay considers the intellectual dilemmas of presenting lives in broadcast formats, particularly radio, focusing on audience, function, and representation. How much fiddling with facts and milieu is permissible in the adaptive process? How can writers ensure integrity of their material when broadcast?

David King Dunaway

1997-01-01

440

Radio and Biography  

Microsoft Academic Search

:Scholars and authors sometimes lament that broadcast versions of written biographies are inaccurate or simplistic. This essay considers the intellectual dilemmas of presenting lives in broadcast formats, particularly radio, focusing on audience, function, and representation. How much fiddling with facts and milieu is permissible in the adaptive process? How can writers ensure integrity of their material when broadcast?

David King Dunaway

1997-01-01

441

NationalRadio Observatory  

E-print Network

-on learning about the incredible space science we do! WestVirginia's SpacePlace www.nrao.edu/VisitGB 304-456-2150 Check out the Green Bank Science Center on Facebook for updated events & specials! W VTOURISM.COM 800 exhibits and displays in our exhibit hall where you will discover what radio astronomers are learning about

Groppi, Christopher

442

Educational Broadcasting--Radio.  

ERIC Educational Resources Information Center

This manual is intended for those who must conduct educational radio broadcasting training courses in Asia-Pacific countries without the resources of experienced personnel, as well as for individuals to use in self-learning situations. The selection of material has been influenced by the need to use broadcasting resources effectively in programs…

Ahamed, Uvais; Grimmett, George

443

Some Fundamental Limitations for Cognitive Radio  

E-print Network

' & $ % Some Fundamental Limitations for Cognitive Radio Anant Sahai Wireless Foundations, UCB EECS program November 1 at BWRC Cognitive Radio Workshop #12;' & $ % Outline 1. Why cognitive radios? 2 November 1 at BWRC Cognitive Radio Workshop #12;' & $ % Apparent spectrum allocations · Traditional

Sahai, Anant

444

(Not) Advising Corporate Officers about Fiduciary Duties  

Microsoft Academic Search

This Article explores the intersection of an important, unresolved corporate law issue and an overlooked professional responsibility issue persistently arising in the corporate milieu. The corporate law question currently unaddressed in Delaware law is whether the fiduciary duties of corporate officers, as agents, are the same as, or different from, the fiduciary duties of corporate directors. A related question is

Lyman P. Q. Johnson; Robert V. Ricca

2007-01-01

445

Operating frequencies for educational satellite services  

NASA Technical Reports Server (NTRS)

The factors affecting the choice of transmission frequencies are identified. These include international radio regulations, natural environment, man-made environment, hardware considerations, and interconnection and spectrum space considerations. An analysis is presented of international radio regulations with emphasis on 1963 EARC and 1971 WARC frequency allocations, powerflux density restrictions, and resolutions concerning introduction of broadcasting-satellite systems. Natural-environmental effects were divided into two categories: (1) those due to transionospheric propagation, and (2) those that can be credited to the earth's atmosphere and its constituents. The frequency dependence of the signal attenuation, signal distortion, and contributions to system noise temperature due to environmental effects are discussed, and comparisons were made for frequencies of interest. Man-made environmental effects were examined in terms of various sharing limitations as well as the indigenous noise contribution to the overall system noise.

Singh, J. P.

1971-01-01

446

Mobile satellite communications in the Forest Service  

NASA Technical Reports Server (NTRS)

There are usually some places within a forest that do not have adequate communication coverage due to line-of-sight or other reasons. These areas are generally known by the foresters and radio technicians and allowances are made for that when working or traveling in those areas. However, when wildfire or other emergencies occur, communications are vital because wildfires can require hundreds of firefighters and cover thousands of acres. During these emergency operations, the existing communications are not adequate and complete radio systems are moved into the area for the conduct of fire communications. Incident command posts (ICPs) and fire camps are set up in remote locations and there is constant need for communications in the fire area and to agency headquarters and dispatch offices. Mobile satellite communications would be an ideal supplement to the Forest Service's current communications system in aiding forest fire control activities.

Warren, John R.

1988-01-01

447

Mobile satellite communications in the Forest Service  

NASA Astrophysics Data System (ADS)

There are usually some places within a forest that do not have adequate communication coverage due to line-of-sight or other reasons. These areas are generally known by the foresters and radio technicians and allowances are made for that when working or traveling in those areas. However, when wildfire or other emergencies occur, communications are vital because wildfires can require hundreds of firefighters and cover thousands of acres. During these emergency operations, the existing communications are not adequate and complete radio systems are moved into the area for the conduct of fire communications. Incident command posts (ICPs) and fire camps are set up in remote locations and there is constant need for communications in the fire area and to agency headquarters and dispatch offices. Mobile satellite communications would be an ideal supplement to the Forest Service's current communications system in aiding forest fire control activities.

Warren, John R.

1988-05-01

448

CRAF Handbook for Radio Astronomy  

E-print Network

CRAF Handbook for Radio Astronomy EUROPEAN SCIENCE FOUNDATION Committee on Radio Astronomy forum for science. The ESF Expert Committee on Radio Astronomy Frequencies, CRAF, was established Astronomy Service and other passive applications. Cover: The 76-m diameter Lovell Telescope at Jodrell Bank

Rodriguez, Luis F.

449

Microwave instrumentation for radio astronomy  

Microsoft Academic Search

Radio astronomy is a branch of science that allows observation of natural radio signals from cosmic sources. Microwave techniques are employed in large radio telescope systems in diverse ways. Starting with early vacuum tube receivers at meter wavelengths, low-noise receivers have pushed the leading edge of technology, culminating in present-day receivers employing HFET amplifiers, superconducting tunnel junctions, and other advanced

John C. Webber; Marian W. Pospieszalski

2002-01-01

450

Radio disturbance warning issuance system  

NASA Technical Reports Server (NTRS)

A radio disturbance warning issuance system was introduced in the Hiraiso Branch of the Radio Research Laboratories in 1972 to reconstruct the current radio disturbance warning service as a social information service. A description of the new ideas which were experimentally systematized by means of an electronic computer is presented.

Maeda, R.; Inuki, H.

1979-01-01

451

Spectrum Sensing for Cognitive Radio  

Microsoft Academic Search

Spectrum sensing is the very task upon which the entire operation of cognitive radio rests. For cognitive radio to fulfill the potential it offers to solve the spectrum underutilization problem and do so in a reliable and computationally feasible manner, we require a spectrum sensor that detects spectrum holes (i.e., underutilized subbands of the radio spectrum), provides high spectral-resolution capability,

Simon Haykin; David J. Thomson; Jeffrey H. Reed

2009-01-01

452

Intelligence artificielle et radio cognitive  

E-print Network

Intelligence artificielle et radio cognitive Badr Benmammar badr.benmammar@gmail.com cel-00680196,version2-25Mar2012 #12;2 Plan Intelligence artificielle et radio cognitive Algorithmes intelligents Réseaux de neurones Logique floue Processus de décision de Markov Langages de la radio cognitive Domaines

Paris-Sud XI, Université de

453

Mathematical Foundations of Cognitive Radios  

E-print Network

Mathematical Foundations of Cognitive Radios Romain Couillet and M´erouane Debbah Abstract. In this paper, we intro- duce a fundamental vision of cognitive radios from a physical layer viewpoint -- Recently, much interest has been directed towards software defined radios and embedded intelligence

Paris-Sud XI, Université de

454

Cognitive Radio: Fundamentals and Opportunities  

E-print Network

Cognitive Radio: Fundamentals and Opportunities Robert H. Morelos-Zaragoza Department of Electrical Engineering San Jose State University October 12, 2007 #12;Cognitive Radio - RHMZ - 2007 Slide 2 of 18 Outline. Cognitive radio (CR) a) Definition and overview (Mitola) b) CR features (FCC) 3. Unlicensed TV spectrum

Morelos-Zaragoza, Robert H.

455

Language Issues for Cognitive Radio  

E-print Network

INVITED P A P E R Language Issues for Cognitive Radio Computer languages that may be useful for expressing cognitive radio concepts are identified and evaluated in this tutorial paper. By Mieczyslaw M aspects of formal languages in the context of cognitive radio. A bottom up approach is taken in which

Kokar, Mieczyslaw M.

456

John E. Hibbard National Radio  

E-print Network

John E. Hibbard National Radio Astronomy Observatory The Antennae Galaxies: Archetype for Colliding Galaxies #12;The Antennae: A Merger Prototype J. Hibbard, NRAO 203rd AAS Jan 9 2004 Talk Outline of radio galaxiesUsed to support collisional origin of radio galaxies (Baade & Minkowski 1954, ApJ, 119

Hibbard, John

457

Collaborative Beamfocusing Radio (COBRA)  

NASA Astrophysics Data System (ADS)

A Ziva team has recently demonstrated a novel technique called Collaborative Beamfocusing Radios (COBRA) which enables an ad-hoc collection of distributed commercial off-the-shelf software defined radios to coherently align and beamform to a remote radio. COBRA promises to operate even in high multipath and non-line-of-sight environments as well as mobile applications without resorting to computationally expensive closed loop techniques that are currently unable to operate with significant movement. COBRA exploits two key technologies to achieve coherent beamforming. The first is Time Reversal (TR) which compensates for multipath and automatically discovers the optimal spatio-temporal matched filter to enable peak signal gains (up to 20 dB) and diffraction-limited focusing at the intended receiver in NLOS and severe multipath environments. The second is time-aligned buffering which enables TR to synchronize distributed transmitters into a collaborative array. This time alignment algorithm avoids causality violations through the use of reciprocal buffering. Preserving spatio-temporal reciprocity through the TR capture and retransmission process achieves coherent alignment across multiple radios at ~GHz carriers using only standard quartz-oscillators. COBRA has been demonstrated in the lab, aligning two off-the-shelf software defined radios over-the-air to an accuracy of better than 2 degrees of carrier alignment at 450 MHz. The COBRA algorithms are lightweight, with computation in 5 ms on a smartphone class microprocessor. COBRA also has low start-up latency, achieving high accuracy from a cold-start in 30 ms. The COBRA technique opens up a large number of new capabilities in communications, and electronic warfare including selective spatial jamming, geolocation and anti-geolocation.

Rode, Jeremy P.; Hsu, Mark J.; Smith, David; Husain, Anis

2013-05-01

458

Far-IR and Radio Thermal Continua in Solar Flares  

Microsoft Academic Search

With the invention of new far-infrared (FIR) and radio mm and sub-mm instruments (DESIR on SMESE satellite, ESO-ALMA), there is a growing interest in observations and analysis of solar flares in this so far unexplored wavelength region. Two principal radiation mechanisms play a role: the synchrotron emission due to accelerated particle beams moving in the magnetic field and the thermal

J. Kasparová; P. Heinzel; M. Karlický; Z. Moravec; M. Varady

2009-01-01

459

Satellite Feature Identification: Cyclogenesis  

NSDL National Science Digital Library

This module, Satellite Feature Identification: Cyclogenesis, uses water vapor satellite imagery to present a satellite perspective of basic features associated with the formation and development of extratropical cyclones. First, through an initial case study, the precursor elements leading to cyclogenesis are identified. Then three conceptual views of different ways cyclogenesis can evolve are presented along with additional examples to illustrate the concepts. Finally a series of exercises, again using real case studies, are used to emphasize the important points and provide realistic scenarios describing some of the many ways cyclogenesis reveals itself on satellite imagery. This module is part of the series: 'Dynamic Feature Identification: The Satellite Palette'.

Comet

2012-08-17

460

Digital satellite communications  

NASA Astrophysics Data System (ADS)

The use of satellite communications in point-to-multipoint transmission of data is studied. The theory, systems, and equipment for satellite communications are described. The topics of satellite orbits, satellite construction, earth station equipment, and the analysis of the satellite link are discussed. Different types of digital modulation for carrier transmission, and techniques for enhancing the transmission capacity, such as digital speech interpolation and demand assignment, are examined. Techniques and equipment for performing the multiple access-broadcasting functions including FDMA, TDMA, DAMA, CDMA, and random access are considered.

Ha, T. T.

1986-06-01

461

Weather Satellite and Orbits  

NSDL National Science Digital Library

In this interactive, online module, students learn about satellite orbits (geostationary and polar), remote-sensing satellite instruments (radiometers and sounders), satellite images, and the math and physics behind satellite technology. The module is part of an online course for grades 7-12 in satellite meteorology, which includes 10 interactive modules. The site also includes lesson plans developed by teachers and links to related resources. Each module is designed to serve as a stand-alone lesson, however, a sequential approach is recommended. Designed to challenge students through the end of 12th grade, middle school teachers and students may choose to skim or skip a few sections.

462

The importance of Radio Quiet Zone (RQZ) for radio astronomy  

NASA Astrophysics Data System (ADS)

Most of radio observatories are located in isolated areas. Since radio sources from the universe is very weak, astronomer need to avoid radio frequency interference (RFI) from active spectrum users and radio noise produced by human made (telecommunication, mobile phone, microwave user and many more. There are many observatories around the world are surrounded by a Radio Quiet Zone (RQZ), which is it was set up using public or state laws. A Radio Quiet Zone normally consists of two areas: an exclusive area in which totally radio emissions are forbidden, with restrictions for residents and business developments, and a larger (radius up to 100 km above) coordination area where the power of radio transmission limits to threshold levels. Geographical Information System (GIS) can be used as a powerful tool in mapping large areas with varying RQZ profiles. In this paper, we report the initial testing of the usage of this system in order to identify the areas were suitable for Radio Quiet Zone. Among the important parameters used to develop the database for our GIS are population density, information on TV and telecommunication (mobile phones) transmitters, road networks (highway), and contour shielding. We will also use other information gathered from on-site RFI level measurements on selected 'best' areas generated by the GIS. The intention is to find the best site for the purpose of establishing first radio quiet zones for radio telescope in Malaysia.

Umar, Roslan; Abidin, Zamri Zainal; Ibrahim, Zainol Abidin

2013-05-01

463

ABC of Satellites for Educators.  

ERIC Educational Resources Information Center

Introduces the basic concepts and elements of satellite and telecommunications satellites. Identifies the advantages of using the unique characteristics of telecommunications satellites in education. Lists cautions of using telecommunications satellite systems to deliver educational programs. (Author/AEF)

Wang, Shousan

1995-01-01

464

Corporate Science and Technology Libraries  

Microsoft Academic Search

This paper traces the growth and development of corporate libraries from their nineteenth century beginnings to the present date; notes the major factors which have influenced their development; and relates many of the innovative changes in systems, procedures, and services in these libraries to the ingenuity and dedication of corporate librarians.

Edythe Moore

1988-01-01

465

Show off the corporate library  

Microsoft Academic Search

Some published evidence has suggested that corporate libraries are slowly becoming irrelevant in meeting organisational information needs due to old-fashioned models of service delivery. Elsewhere in the literature the intranet is heralded as a technological tool for corporate information management. This paper provides the results of a series of case studies completed in 1998. The purpose of the research was

Hazel Hall; Alyn M Jones

2000-01-01

466

The Farm and Ranch Corporation.  

E-print Network

rooc - ~ TA245.7 1873 0.1302 The Texas A&M University System Texas Agricultural Extension Service 8-1302 Director Daniel C. Pfannstiel College Station, Texas 77843 The Farm and Ranch Corporation Farm and Ranch Busin 0 nization... in Texas CONTENTS Alternative Forms of Business Organization. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 3 Closely Held Farm Corporations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 4...

Brints, Norman; Sartin, Marvin

1980-01-01

467

The Banning of Corporal Punishment.  

ERIC Educational Resources Information Center

Presents the 1985 resolution of the Association for Childhood Education International (ACEI) for participation in the interdisciplinary effort to ban corporal punishment. Discusses distinctions between discipline and child abuse. Reports medical and psychological effects of physical punishment, and relationships between school corporal punishment…

Cryan, John R.

1995-01-01

468

Is Corporate Criminal Liability Unique?  

Microsoft Academic Search

Critics of corporate criminal liability argue that federal criminal law is far too broad, sanctions are imposed without fault, federal sentences are too harsh, and, finally, that federal prosecutors have too much power. This article makes two points about these critiques. First, although there is merit to each of these arguments, they cannot be limited to corporate criminal liability. Rather,

Sara S. Beale

2008-01-01

469

Theory "W": The Corporate Warrior.  

ERIC Educational Resources Information Center

Describes power structure of corporations functioning under Theory W in which single leaders, in partnership with trusted followers, achieve corporate success. Basis of this industrial structure is attributed to social and developmental structures of prehistoric man and city states. Dimensions of W, X, Y, and Z theories are discussed. (MBR)

Morris, David J., Jr.

1986-01-01

470

The Changing Shape of Corporations.  

ERIC Educational Resources Information Center

This newsletter contains two articles dealing with the changing shape of corporations. The article "Trends in Business Culture" argues that Wal-Mart's emergence as the largest corporation in the United States reflects the larger economic shift in the U.S. economy from production of goods to provision of abstract goods such as services and…

Wagner, June G.

2003-01-01

471

Corporate Reputation: The Definitional Landscape  

Microsoft Academic Search

While interest in the concept of corporate rep- utation has gained momentum in the last few years, a precise and commonly agreed upon definition is still lacking. This paper reviews the many definitions of corporate reputation present in the recent literature and categorizes these definitions based on their similarities and differences. The purpose of the study is to review, analyze

Michael L. Barnett; John M. Jermier; Barbara A. Lafferty

2006-01-01

472

Corporate reputation: the boardroom challenge  

Microsoft Academic Search

Boardroom recognition of the importance of reputation as a key business driver is growing. This article analyses the findings of the Corporate Reputation Watch – a study by Harris Interactive for Hill and Knowlton – which examines the attitudes towards corporate reputation of over 800 CEOs and senior business figures from seven countries across Europe and North America. The survey

Andrew Pharoah

2003-01-01

473

Corporate reputation: Meaning and measurement  

Microsoft Academic Search

Corporate reputation has attracted interest from a wide range of academic disciplines. It is also a growing focus for business and media attention. This paper examines the construct of corporate reputation, first by untangling the terminological problems that have been caused by the interdisciplinary nature of much of the earlier work in the area. The construct of reputation and the

Rosa Chun

2005-01-01

474

Corporate reputation: concept and measurement  

Microsoft Academic Search

Corporate reputation is formed by the firm’s various publics on the basis of information and experience. Different publics consider different informational cues. Focusses on the cues considered by customers of a beverage firm. Uses focus groups and a survey among consumers to develop an instrument to measure corporate reputation. The instrument can be used to track the evolution of the

Albert Caruana

1997-01-01

475

Corporate Reputation: Image and Identity  

Microsoft Academic Search

ABSTRACT It is fruitful to consider two complementary per- spectives on the concept of corporate reputation and its relationship to success and credibility. The first of these can be said to be a managerial or pragmatic perspective. Its basis is economic rationality and it focuses on traditional notions of corporate success. It is primarily concerned with the qualities imputed to

Peter Pruzan

2001-01-01

476

Corporate Connections The Bath Advantage  

E-print Network

Corporate Connections The Bath Advantage Daniel Goord, BSc in Business Administration, on placement The Corporate Partners Scheme Contact us (inside back cover) www.bathconnectsyou.com Contents 02 03 05 06 06 07 have an excellent reputation for business education and international research. We work with a wide

Burton, Geoffrey R.

477

Corporations on the Front Line  

Microsoft Academic Search

Over the past few years multinational corporations have been coming increasingly under attack from a number of forces, including non governmental organisations, “political shoppers” and grass root activists. While these civil or market based forms of regulation have had some effect in moderating corporate behaviour, this paper argues that the effect is necessarily limited. What is proving to be more

Noreena Hertz

2004-01-01

478

Corporate universities of the future  

Microsoft Academic Search

Corporate universities, like other lines of business within an enterprise, have customers and other stakeholders whose wants need to be satisfied. They operate in an environment subject to demographic, technological, and political trends that could affect their business. The leaders of corporate universities need to define the business situation they face so as to leverage their university’s strengths, minimize its

Stephen A. Stumpf

1998-01-01

479

Corporate Governance in Financial Institutions  

Microsoft Academic Search

On 29th - 30th March 2007, SUERF and the Central Bank of Cyprus jointly organized a Seminar: Corporate Governance in Financial Institutions. The papers in the present publication are based on a sample of the presentations at the Seminar. Together, the papers illuminate a number of key issues in corporate governance in a variety of financial firms. In the first

Spyros G. Stavrinakis; Christian Harm; David T. Llewellyn; Bridget Gandy; Peter Shaw; Peter Tebbutt; Mark Young

480

Corporate Governance for Shareholder Value  

Microsoft Academic Search

In the last few years there has been serious debate about the generally poor quality of corporate governance in Indian companies and the need to improve the same. This has led to the publication of a recommended code of corporate governance by the Confederation of Indian Industry (CII). More recently, the Securities and Exchange Board of India (SEBI) formed its

Venkiteswaran N

481

Western Electric's Corporate Education Center  

Microsoft Academic Search

The Western Electric Corporate Education Center in Hopewell, NJ, was opened in 1969, centralizing the Company's corporate technical-professional and management educational programs under one roof. The technical-professional curricula is administered under the Graduate Engineering and Information Systems Program, which has gone through an evolutionary period over the years, changing when necessary to keep in the forefront of new knowledge and

Hugh L. Janney

1976-01-01

482

Forestry Commission England Corporate Plan  

E-print Network

this corporate plan which sets out how the Forestry Commission in England will work with a wide range of partners this corporate plan which sets out how the Forestry Commission will contribute towards delivering these goals. I they are highly-valuable places to visit and enjoy. Our natural environment underpins our economic prosperity, our

483

Build It Yourself: Satellite!  

NSDL National Science Digital Library

"Build It Yourself: Satellite!" is an online Flash game hosted on the James Webb Space Telescope website. The goal of the game is to explain the decision-making process of satellite design. The user can choose to build a "small," "medium," or "large" astronomy satellite. The user then selects science goals, wavelength, instruments, and optics. The satellite is then launched on the appropriate rocket (shown via an animation). Finally, the user is shown what their satellite might look like, as well as what kind of data it might collect, via examples from similar real-life satellites. Satellites range from small X-ray missions without optics (like the Rossi X-ray Timing Explorer) to large missions with segmented mirrors (like the James Webb Space Telescope).

484

EMC of ground-based and space radio services - Criteria, conditions, and calculations  

NASA Astrophysics Data System (ADS)

Attention in this monograph is first given to the types of radio signals employed in ground-based and space radio services; their energy spectra are examined, and a description is given of methods for calculating interference for different combinations of signal and interference. Conditions for the satisfaction of EMC criteria are described, and the calculation of the required angular distribution of geostationary satellites is discussed. The effective utilization of the geostationary orbit and its potential capacity is considered.

Borodich, Sergei V.

485

The optical communication link outage probability in satellite formation flying  

NASA Astrophysics Data System (ADS)

In recent years, several space systems consisting of multiple satellites flying in close formation have been proposed for various purposes such as interferometric synthetic aperture radar measurement (TerraSAR-X and the TanDEM-X), detecting extra-solar earth-like planets (Terrestrial Planet Finder-TPF and Darwin), and demonstrating distributed space systems (DARPA F6 project). Another important purpose, which is the concern of this paper, is for improving radio frequency communication to mobile terrestrial and maritime subscribers. In this case, radio frequency signals from several satellites coherently combine such that the received/transmit signal strength is increased proportionally with the number of satellites in the formation. This increase in signal strength allows to enhance the communication data rate and/or to reduce energy consumption and the antenna size of terrestrial mobile users' equipment. However, a coherent combination of signals without aligning the phases of the individual communication signals interrupts the communication and outage link between the satellites and the user. The accuracy of the phase estimation is a function of the inter-satellite laser ranging system performance. This paper derives an outage probability model of a coherent combination communication system as a function of the pointing vibration and jitter statistics of an inter-satellite laser ranging system tool. The coherent combination probability model, which could be used to improve the communication to mobile subscribers in air, sea and ground is the main importance of this work.

Arnon, Shlomi; Gill, Eberhard

2014-02-01

486

Law and Legal Theory in the History of Corporate Responsibility: Corporate Personhood  

Microsoft Academic Search

This paper, part of a larger scholarly project, addresses one of four areas – i.e., the emergence of corporate personhood – where, historically, law has both influenced and mirrored cultural expectations concerning corporate responsibility. The other areas (treated elsewhere) are corporate purpose, corporate regulation, and corporate governance. Corporate personhood is a subject of longstanding and recurring interest that, notwithstanding it

Lyman P. Q. Johnson

2012-01-01

487

Survey: National Environmental Satellite Service  

NASA Technical Reports Server (NTRS)

The national Environmental Satellite Service (NESS) receives data at periodic intervals from satellites of the Synchronous Meteorological Satellite/Geostationary Operational Environmental Satellite series and from the Improved TIROS (Television Infrared Observational Satellite) Operational Satellite. Within the conterminous United States, direct readout and processed products are distributed to users over facsimile networks from a central processing and data distribution facility. In addition, the NESS Satellite Field Stations analyze, interpret, and distribute processed geostationary satellite products to regional weather service activities.

1977-01-01

488

Digital Audio Radio Broadcast Systems Laboratory Testing Nearly Complete  

NASA Technical Reports Server (NTRS)

Radio history continues to be made at the NASA Lewis Research Center with the completion of phase one of the digital audio radio (DAR) testing conducted by the Consumer Electronics Group of the Electronic Industries Association. This satellite, satellite/terrestrial, and terrestrial digital technology will open up new audio broadcasting opportunities both domestically and worldwide. It will significantly improve the current quality of amplitude-modulated/frequency-modulated (AM/FM) radio with a new digitally modulated radio signal and will introduce true compact-disc-quality (CD-quality) sound for the first time. Lewis is hosting the laboratory testing of seven proposed digital audio radio systems and modes. Two of the proposed systems operate in two modes each, making a total of nine systems being tested. The nine systems are divided into the following types of transmission: in-band on-channel (IBOC), in-band adjacent-channel (IBAC), and new bands. The laboratory testing was conducted by the Consumer Electronics Group of the Electronic Industries Association. Subjective assessments of the audio recordings for each of the nine systems was conducted by the Communications Research Center in Ottawa, Canada, under contract to the Electronic Industries Association. The Communications Research Center has the only CCIR-qualified (Consultative Committee for International Radio) audio testing facility in North America. The main goals of the U.S. testing process are to (1) provide technical data to the Federal Communication Commission (FCC) so that it can establish a standard for digital audio receivers and transmitters and (2) provide the receiver and transmitter industries with the proper standards upon which to build their equipment. In addition, the data will be forwarded to the International Telecommunications Union to help in the establishment of international standards for digital audio receivers and transmitters, thus allowing U.S. manufacturers to compete in the world market.

2005-01-01

489

Audience participation in radio development programmes: A study of radio seremban, a Malaysian local radio station  

Microsoft Academic Search

Among the methods adopted to accelerate rural quality of life in Malaysia is a continuous dissemination of development messages to the people. The local radio stations in the country are expected to be effective sources for the rural population's participation in radio for development. To what extent do the rural audience participate in the local radio development programmes? What factors

Adam Tanko Zakariah

1993-01-01

490

Satellite Communications with NRAO Green Bank Antennas  

NASA Astrophysics Data System (ADS)

The National Radio Astronomy Observatory's Green Bank facility has several medium and large antennas that are available for satellite communications. The 100 meter Robert C. Byrd Green Bank Telescope (GBT), the largest and most sensitive antenna on site, is capable of receiving signals at frequencies as high as 86 GHz. In addition to the GBT are the fully operational 43 meter, 20 meter, and 13.7 meter antennas, and three mothballed 26 meter antennas. A transmitter could be fitted to any of these antennas for spacecraft uplinks. We discuss the characteristics of these antennas and possible operational models for future planetary science mission support.

Ford, John M.; Ford, H. Alyson; Watts, Galen

2014-11-01

491

Static Inflation Test of 135 foot satellite  

NASA Technical Reports Server (NTRS)

Series showing inflation test of Echo I in Weeksville, N.C. L61-4603 shows Echo team, Wm. J. O'Sullivan is tallest, in center, Walter Bressette is to his left. (this inflation took place in 1958, LaRC copied the photos from Schjendahl Co. in 1961.) L61-4597: ECHO 1 was America's first passive communications satellite, a 100 foot diameter aluminized Mylar plastic balloon that reflected radio signals beyond Earth's curvature. Photograph published in Winds of Change, 75th Anniversary NASA publication (page 79), by James Schultz.

1961-01-01

492

Ionospheric limitations to time transfer by satellite  

NASA Technical Reports Server (NTRS)

The ionosphere can contribute appreciable group delay and phase change to radio signals traversing it; this can constitute a fundamental limitation to the accuracy of time and frequency measurements using satellites. Because of the dispersive nature of the ionosphere, the amount of delay is strongly frequency-dependent. Ionospheric compensation is necessary for the most precise time transfer and frequency measurements, with a group delay accuracy better than 10 nanoseconds. A priori modeling is not accurate to better than 25%. The dual-frequency compensation method holds promise, but has not been rigorously experimentally tested. Irregularities in the ionosphere must be included in the compensation process.

Knowles, S. H.

1983-01-01

493

Sputnik 1 and the First Satellite Ionospheric Experiment  

NASA Astrophysics Data System (ADS)

The world's first scientific space experiment was carried out in 1957 during the flight of the first Artificial Earth Satellite (AES) - Sputnik 1. It was an ionospheric experiment performed at IZMIRAN under the direction of Prof. Ya.L.Alpert (1911-2010). The sunrise and sunset variations in the AES radio signal were recorded in order to determine the distribution of electron density in the topside ionosphere (above the maximum). The experiment demonstrated the capabilities of the satellite radio beacon method, which is now very important and widely used for studying the ionosphere. Our report submitted to the COSPAR General Assembly in Russia describes the history and results of that experiment, as well as some other contributions by Ya.L.Alpert to ionospheric research. Yakov L.Alpert was one of the most famous and influential radiophysicists of his time, the author of many fundamental studies and of a number of classic books on the theory of propagation of electromagnetic waves, interaction of artificial bodies with ionospheric plasmas, ionospheric radio scattering, and the use of satellite radio beacon methods for studying the ionosphere.

Sinelnikov, Vyacheslav; Kuznetsov, Vladimir; Alpert, Svetlana

494

Corporate Governance, the Environment, and the Internet  

E-print Network

Internet, and the highly publicized importance of good corporate governance (Corporate Governance, the Environment, and the Internet JaneInternet have the potential to contribute significantly to good corporate governance.

Andrew, Jane

2003-01-01

495

Corporate Support of Education: Some Strings Attached  

ERIC Educational Resources Information Center

Corporate self-interest should guide corporate giving. Managers of publicly held corporations have the right, the capability, and the obligation to establish a philosophical screen to use in determining how shareholders' money is to be donated. (Author/MLF)

Malott, Robert H.

1978-01-01

496

75 FR 64785 - Corporate Credit Unions  

Federal Register 2010, 2011, 2012, 2013

...serve at the corporate by their...of their responsibilities to the NPCU...permits a corporate, if it makes a good faith determination...fiduciary responsibility; (ii...with the corporate credit union...directors, in good faith,...

2010-10-20

497

International Corporate Leadership A uniquely integrated approach  

E-print Network

International Corporate Leadership Programme A uniquely integrated approach The summer work The International Corporate Leadership Programme (ICLP) provides companies with top quality engineering students. International Corporate Leadership Programme `Graduates ready for business' Integrated with degree Mentored

Berzins, M.

498

Harvard University Corporation Committee on Shareholder Responsibility  

E-print Network

of issues of social responsibility that are put before corporate shareholders. Shareholder proposals of social concern and corporate responsibility raised through the proxy process. Because the CCSR's role1 Harvard University Corporation Committee on Shareholder Responsibility Annual Report, 2011

499

Tax consequences of separating corporate businesses  

E-print Network

. (1) The distributing corporation and the con- trolled corporation are each engaged in the active conduct of a trade or business immedi- ately after the distribution of stock or securi- ties of the controlled corporation; or (2) Immediately before.... (1) The distributing corporation and the con- trolled corporation are each engaged in the active conduct of a trade or business immedi- ately after the distribution of stock or securi- ties of the controlled corporation; or (2) Immediately before...

Zuber, Gordon Dewey

2012-06-07

500

Density waves in Saturn's rings probed by radio and optical occultation - Observational tests of theory  

NASA Technical Reports Server (NTRS)

A parallel examination is conducted of Voyager radio and photopolarimeter occultation observations of the Saturn A ring's density waves. The radio instrument waves exhibit an average -90 deg offset from the dynamical phase. A warping height of about 100-m amplitude can qualtitatively reproduce this phase shift, while preserving the overall model wave shape. These results may be profoundly relevant for satellite-ring torque calculations in Saturn's rings, given the deposition of all of the net torque of the standard model in the first wavelength.

Brophy, Thomas G.; Rosen, Paul A.

1992-01-01