by Cubic Corporation, National Aeronautics and Space Administration, National Technical Information Service, distributor in San Diego, Calif, [Washington, DC, Springfield, Va .
Written in English
Microfiche. [Washington, D.C. : National Aeronautics and Space Administration, 1985] 2 microfiches.
|Other titles||Trade off between land vehicle antenna cost and gain for satellite mobile communications.|
|Series||NASA contractor report -- NASA-CR-175732.|
|Contributions||United States. National Aeronautics and Space Administration.|
|The Physical Object|
Get this from a library! Trade-off between land vehicle antenna cost and gain for satellite mobile communications: interim report.. [United States. National Aeronautics and Space Administration.;]. Some of the factors that drive the cost of satellites are the equipment and materials used to build them. Transponders alone hundreds of thousands of dollars a year to maintain, while bandwidth cost per MHz is priced at a minimum of about $3, a month. Running a satellite at a 36MHz bandwidth will cost over $ million a year. array antenna for land mobile satellite communications are described. The antenna system includes an array of six microstrip stacked patch antennas, each connected to an RF channel, which include an MMIC Low Noise Amplifier and a commercial silicon monolithic I-Q modulator. A 6-way microstrip combiner adds the six channels so that the resulting. The AQYR is a completely automatic meter flyaway antenna designed for the Viasat Exede HTS satellite network. This system points the antenna at the satellite with just the touch of a single button, and delivers the full 15 Mb X 5 Mb Exede HTS service in .
2. Land Mobile Satellite Service. The Land mobile satellite service has a mobile earth station located on different types of trains and other transportation systems. This service consists of a personal location beacon terminal that acts as an earth station. The ultimate purpose of the satellite antenna is to act like a spatial filter, focusing the antenna beam on the desired area on the Earth with the desired polarization, while being isolated from other areas. Satellite‐borne communications antennas are located very far . The Land Mobile Satellite Channel. On the other hand, mobile satellite systems usually operate at the L or S bands, and more recently also in Ku-band. Markov chain models are usually employed to depict the eventual blocking of the line-of-sight, with superposing micro (fast) and macro (slow) fading fluctuations within each state of the model. 24 Impedence Matching in Antenna Systems 25 Mobile, Emergency, Portable, and Marine book on the marketthat people can give to a any time. ix _FM_Carr 4/10/01 PM Page ix. Antennas have changed a lot over the years. Figure I-1 shows how antennas were between and This facility was the first U.S. Navy radio.
maximal achievable gain presented in the same table, the actual peak gain will be the minimum between the previously calculated value and the value for the maximum gain corresponding to the given antenna design. To obtain the net transmit antenna gain, we must add to this peak gain (in dB) the losses (in dB) due to a pointing offset: Lθ=−12(eθ). Overview In the beginning of radio development, mobile communication systems were conceived for the transmission and receiving of telegraphy and telephony signals via antenna from ships, cars, trains and aircraft. Learn more about Chapter 4: Antenna Systems for Mobile Satellite Applications on GlobalSpec. i NTIA TM Antenna Models For Electromagnetic Compatibility Analyses C.W. Wang, Ph.D. T. Keech, Ph.D. U.S. Department of Commerce Rebecca Blank, Acting Secretary. Outfitter Satellite is your best source for rack-mountable in-vehicle satellite phones and docking stations for Iridium, Iridium PTT, Inmarsat GSPS, and Thuraya handheld satellite phones. Various features are available depending on the equipment you select including: handsfree speakers, privacy handsets and RJ11 phone ports.