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Issue 2: Propagation Campaign and Results

Special Effects: Antenna Wetting, Short Distance Diversity and Depolarization

Roberto J. Acosta

Abstract | Full Paper (PDF, 1.4 MB)

The Advanced Communication Technology Satellite (ACTS) communications system operates in the Ka frequency band. ACTS uses multiple, hopping, narrow beams and very small aperture terminal (VSAT) technology to establish a system availability of 99.5% for bit-error-rates of 5x 10-7 or better over the continental United States. In order maintain this minimum system availability in all US rain zones, ACTS uses an adaptive rain fade compensation protocol to reduce the impact of signal attenuation resulting from propagation effects. The purpose of this paper is to present the results of system and sub-system characterizations considering the statistical effects of system variances due to antenna wetting and depolarization effects. In addition the availability enhancements using short distance diversity in a sub-tropical rain zone are investigated.

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Issue No. 2:
NASA's Advanced Communications Technology Satellite (ACTS)

Fall 2002

General Editor Introduction

From the Guest Editor


Historical Development:
p. 1
, p. 2, p. 3

p. 1
, p. 2

On-Orbit Performance

Propagation Campaign and Results


Critical Perspectives

ACTS Shut Down: April 28, 2004

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