Citation
Abstract
The ODSRS (Orbiting Deep Space Relay Station) would be a geostationary or geosynchronous earth satellite designed to receive signals from spacecraft at lunar or planetary distances. A communication link will be required to transfer the data received by the ODSRS to a ground station. This article examines the feasibility of using a “bent-pipe” type system to relay the entire RF signal received by the ODSRS together with its receiving svstem noise to the ground station. The analysis and numerical results presented herein should provide an acceptable basis for selecting an ODSRS/ground link design. The use of a “bent-pipe” channel appears feasible for each of the three ODSRS applications considered herein. Of the three applications considered, the maximum ODSRS transmitter RF power output required was 5.3 watts for a 25 Mbps, uncoded, suppressed-carrier telemetry channel. This calculation assumed that the ODSRS/ground link frequency is 14 GHz, the ODSRS antenna diameter is 2m, the ground antenna diameter is 5 m, and the ground receiving system uses an uncooled parametric amplifier. The results presented herein also indicate that ground adjustment of the ODSRS transmitter RF power output for different spacecraft, different spacecraft modes of operation, and changes in spacecraft /ODSRS range will normally be necessary to avoid violation of CCIR power flux density liniitations.
Details
- Volume
- 42-56
- Published
- April 15, 1980
- Pages
- 76–84
- File Size
- 954.2 KB