Title :
Pragmatic vs. TCM codes. A performance comparison for severely band-limited nonlinear satellite channel
Author :
Dubey, V.K. ; Lim, N.K. ; Gunawan, E.
Author_Institution :
Sch. of Electr. & Electron. Eng., Nanyang Technol. Inst., Singapore
Abstract :
The performances of Ungerboeck trellis-coded-modulation (TCM) codes on band-limited nonlinear satellite channels and of the pragmatic codes, which are standard convolution 1/2-rate codes mapped into M -ary phase-shift-keyed (M-PSK) signals, are reviewed. Using a computer simulation, the performance of a 16-state, 2/3-rate encoder of 8-PSK Ungerboeck and pragmatic codes estimated for band-limited nonlinear satellite channel is presented, demonstrating the robustness of both Ungerboeck and pragmatic codes for severely band-limited nonlinear satellite channels. It is shown that when the band-limitation is too severe, major intersymbol interference occurs, and a coding gain of 0.8 dB and 1.1 dB will be lost for Ungerboeck and pragmatic codes, respectively. When the bandwidth-time product is 1.2, the performance of pragmatic codes is shown to be within 0.8 dB of that of Ungerboeck codes showing that the pragmatic codes are attractive for severely band-limited nonlinear satellite channels
Keywords :
error correction codes; intersymbol interference; phase shift keying; satellite relay systems; telecommunication channels; M-PSK signals; Ungerboeck TCM codes; band-limited nonlinear satellite channels; coding gain; computer simulation; convolutional codes; intersymbol interference; performance comparison; pragmatic codes; Bandwidth; Code standards; Computer simulation; Convolution; Convolutional codes; Decoding; Modulation coding; Robustness; Satellites; Viterbi algorithm;
Conference_Titel :
Global Telecommunications Conference, 1990, and Exhibition. 'Communications: Connecting the Future', GLOBECOM '90., IEEE
Conference_Location :
San Diego, CA
Print_ISBN :
0-87942-632-2
DOI :
10.1109/GLOCOM.1990.116604
