Citation
Abstract
In a previous article, the authors showed that the DSN (7,1/2) convolutional code could be decoded by a simple “quick-look” method that requires only two shift registers of length 7 for the incoming hard-quantized channel symbols. Such a decoder is being developed for Project Galileo to circumvent an incompatibility between the DSN and the Tracking and Data Relay Satellite System (TDRSS), whose versions of the (7,1/2) code differ in the order of the symbols in each pair. Because signal-to-noise ratios are high during the near-Earth phase of the Galileo mission, quick-look decoding is feasible. The present article derives design parameters and performance figures for the three functions of the decoder: acquisition of node synchronization, generation of the decoded bits, and estimation of channel quality.
Details
- Volume
- 42-53
- Published
- October 15, 1979
- Pages
- 93–101
- File Size
- 827.7 KB