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Record Details

Record 74 of 8192
Fade measurements at L-band and UHF in mountainous terrain for land mobile satellite systems
External Online Source: doi:10.1109/8.1081
Author and Affiliation:
Vogel, Wolfhard J.(Texas, University, Austin, United States)
Goldhirsh, Julius(Johns Hopkins University, Laurel, MD, United States)
Abstract: Fading results related to land mobile satellite communications at L-band (1502 MHz) and UHF (870 MHz) are described. These results were derived from an experiment performed in a series of canyon passes in the Boulder, Colorado region of the US. The experimental configuration involved a helicopter as the source platform, which maintained a relatively fixed geometry with a mobile van containing the receiver and data-acquisition system. An unobstructed line of sight between the radiating sources and the receiving van was, for the most part, also maintained. In this configuration, the dominant mechanism causing signal fading (or enhancement) is a result of multipath. The resulting fade distributions demonstrated that at the 1 percent and 5 percent levels, 5.5- and 2.6-dB fades were on the average exceeded at L-band and 4.8- and 2.4-dB at UHF, respectively, for a path elevation angle of 45 deg. The canyon results as compared with previous roadside-tree-shadowing results demonstrate that the deciding factor dictating fade margin for future land mobile satellite systems is tree shadowing rather than fades caused by multipath.
Publication Date: Jan 01, 1988
Document ID:
19880046272
(Acquired Nov 28, 1995)
Accession Number: 88A33499
Subject Category: COMMUNICATIONS AND RADAR
Document Type: Journal Article
Publication Information: IEEE Transactions on Antennas and Propagation (ISSN 0018-926X); 36; 104-113
Publisher Information: United States
Contract/Grant/Task Num: N00039-87-C-5301; JPL-956520
Financial Sponsor: NASA; United States
Organization Source: Texas Univ.; Austin, TX, United States
Johns Hopkins Univ.; Laurel, MD, United States
Description: 10p; In English
Distribution Limits: Unclassified; Publicly available; Unlimited
Rights: Copyright
NASA Terms: LAND MOBILE SATELLITE SERVICE; MICROWAVE ANTENNAS; SIGNAL FADING; ULTRAHIGH FREQUENCIES; DATA ACQUISITION; HELICOPTERS; LEAST SQUARES METHOD; RADIO RECEIVERS; RAYLEIGH SCATTERING
Imprint And Other Notes: IEEE Transactions on Antennas and Propagation (ISSN 0018-926X), vol. 36, Jan. 1988, p. 104-113.
Availability Source: Other Sources
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