NTRS - NASA Technical Reports Server

Back to Results
Simultaneous measurements of L- and S-band tree shadowing for space-Earth communicationsWe present results from simultaneous L- and S-Band slant-path fade measurements through trees. One circularly-polarized antenna was used at each end of the dual-frequency link to provide information on the correlation of tree shadowing at 1620 and 2500 MHz. Fades were measured laterally in the shadow region with 5 cm spacing. Fade differences between L- and S-Band had a normal distribution with low means and standard deviations from 5.2 to 7.5 dB. Spatial variations occurred with periods larger than 1-2 wavelengths. Swept measurements over 160 MHz spans showed that the stdv. of power as function of frequency increased from approximately 1-6 dB at locations with mean fades of 4 and 20 dB, respectively. At a 5 dB fade, the central 90% of fade slopes were within a range of 0.7 (1.9) dB/MHz at L-(S-) Band.
Document ID
Document Type
Conference Paper
Vogel, Wolfhard J. (Texas Univ. Austin, TX United States)
Torrence, Geoffrey W. (Texas Univ. Austin, TX United States)
Lin, Hsin P. (Texas Univ. Austin, TX United States)
Date Acquired
August 17, 2013
Publication Date
January 1, 1995
Publication Information
Publication: Proceedings of the Fourth International Mobile Satellite Conference (IMSC 1995)
Subject Category
Communications and Radar
Funding Number(s)
Distribution Limits
Work of the US Gov. Public Use Permitted.

Related Records

IDRelationTitle19960022452Analytic PrimaryProceedings of the Fourth International Mobile Satellite Conference (IMSC 1995)
Document Inquiry