Title :
A quasi coherent spread spectrum decoder for satellite communications using a low rate convolutional code
Author :
Tomlinson, M. ; Abu Rgheff, M.A.
Author_Institution :
Satellite Centre, Univ. of Plymouth, UK
Abstract :
A new form of bandpass convolutional decoder is presented. The decoder has as its basis, the classic Viterbi algorithm, but uses envelope (energy) detection in order to cope with a frequency offset, phase rotating received signal. The advantage of this decoder is that it does not need to be proceeded by a modem and is not subject to the problems of cycle slips. It can operate at negative input SNR values and is well suited to the decoding of low rate convolutional codes as may be used in CDMA systems. An example is given of a 1/6 rate system operating at 16 kbits/sec using a EUTELSAT satellite
Keywords :
Viterbi decoding; code division multiple access; convolutional codes; quadrature phase shift keying; satellite communication; spread spectrum communication; 16 kbit/s; CDMA systems; EUTELSAT satellite; QPSK modulation; Viterbi algorithm; bandpass convolutional decoder; envelope detection; frequency offset signal; low rate convolutional code; negative input SNR values; phase rotating received signal; quasi coherent spread spectrum decoder; satellite communications; Convolution; Convolutional codes; Decoding; Envelope detectors; Modems; Phase detection; Phase frequency detector; Satellites; Spread spectrum communication; Viterbi algorithm;
Conference_Titel :
Spread Spectrum Techniques and Applications Proceedings, 1996., IEEE 4th International Symposium on
Conference_Location :
Mainz
Print_ISBN :
0-7803-3567-8
DOI :
10.1109/ISSSTA.1996.563191
