Accession Number : ADA118880

Title :   Coding for Navy UHF Satellite Communications (Phase I).

Descriptive Note : Final rept.


PDF Url : ADA118880

Report Date : 01 Apr 1977

Pagination or Media Count : 139

Abstract : For several reasons, coding is potentially attractive in Navy UHF SATCOM applications. We surveyed a broad class of coding techniques to identify a technique which provided the necessary level of coding gain and protection against RFI, and at the same time satisfied a number of other constraints including: (1) Size, weight and power requirements consistent with platform constraints; (2) Compatibility with the existing and expanding inventory of Navy UHF SATCOM equipment; (3) Transparency to operators of the system; and (4) Operability in TDMA as well as non-TDMA systems. The result of this survey is the recommendation of pseudorandomly interleaved convolutional codes with maximum likelihood (Viterbi) decoding. Viterbi decoding is a practical and efficient technique with a proven record in SATCOM applications. We show in this report that in the absence of RFI effects we can provide sufficient coding gain to overcome the projected negative link margins noted above for the SSIXS and TSCIXS channels of FLTSATCOM. Furthermore, the use of interleaving enables us to correct bursts of RFI-induced erasures as well as provide moderate additional gain against thermal noise. Our recommended approach is demonstrated to be superior to several others both on technical and on operational grounds.

Descriptors :   *Satellite communications, Ultrahigh frequency, Communication satellites, Error correction codes, Naval equipment, Radiofrequency interference, Signal processing, Data links

Subject Categories : Unmanned Spacecraft
      Non-radio Communications

Distribution Statement : APPROVED FOR PUBLIC RELEASE