Accession Number:

ADA063779

Title:

Phase Distortion Study (Phase B)

Descriptive Note:

Final rept

Corporate Author:

MAGNAVOX GOVERNMENT AND INDUSTRIAL ELECTRONICS CO TORRANCE CA ADVANCED PRODUCTS DIV

Personal Author(s):

Report Date:

1977-06-30

Pagination or Media Count:

233.0

Abstract:

This is the Final Report of a 6 month study of duobinary digital data transmission over the DSCS. Analysis and computer simulations were developed for evaluating the degradation for duobinary SQPSK in the FDMA and TDMA modes, with emphasis on maximizing the bandwidth utilization capability of duobinary signalling. In a linear channel, single-access duobinary achieves rates of 3 bpsHz, decreasing to 2.5 bpsHz with a saturating transmitter and satellite. For duobinary FDMA, rates to 2.67 bpsHz are possible in a nonsaturating channel with rates to 2.2 bpsHz in a saturating channel. Error correction coding of duobinary is not recommended. Duobinary modem considerations and implementations are discussed in depth. The modem should incorporate phase distortionless maximally-flat filters, a sampling detector, 4-bit quantizer, the Viterbi algorithm, modified sync and phase tracking loops, and preferably an adaptive equalizer. While a new modem design is recommended, modification of the Harris MD-1002 modem for duobinary SQPSK operation is possible, and the required changes are specified in detail. Author

Subject Categories:

  • Cybernetics
  • Unmanned Spacecraft
  • Non-Radio Communications

Distribution Statement:

APPROVED FOR PUBLIC RELEASE