Title :
Optimal soft decoding for combined trellis-coded quantization/modulation
Author :
Ho, Keang-Po ; Chei, Kwok Hung
Author_Institution :
Dept. of Inf. Eng., Chinese Univ. of Hong Kong, Shatin, China
fDate :
6/1/2000 12:00:00 AM
Abstract :
The maximum a posteriori (MAP) algorithm is used as a minimum mean-squared-error decoder for combined trellis-coded quantization and modulation. The optimal trellis-coded quantizer is derived when the soft-decoding MAP algorithm is used as a decoder. The trellis-coded quantizer and the soft decoder are optimized iteratively for minimum overall distortion from transmitter input to receiver output. Significant performance improvement is achieved for both memoryless Gaussian and uniform source, especially for very noisy channels
Keywords :
AWGN channels; iterative decoding; least mean squares methods; memoryless systems; optimisation; quantisation (signal); source coding; trellis coded modulation; trellis codes; AWGN channel; MAP algorithm; MMSE decoder; iterative soft decoder; maximum a posteriori algorithm; memoryless Gaussian source; minimum mean-squared-error decoder; minimum overall distortion; noisy channels; optimal soft decoding; optimal trellis-coded quantizer; performance; receiver output; transmitter input; trellis-coded quantization/modulation; trellis-coded quantizer; uniform source; Algorithm design and analysis; Euclidean distance; Gaussian noise; Iterative algorithms; Iterative decoding; Modulation coding; Quantization; Simulated annealing; Turbo codes; Viterbi algorithm;
Journal_Title :
Communications, IEEE Transactions on
