Trellis quantization with MAP detection for noisy channels

Maximum a posteriori (MAP) detection is applied to trellis quantizers operating over additive white Gaussian noise (AWGN) channels. The use of the MAP method instead of maximum likelihood is motivated by the fact that the source coder output probabilities, conditioned on the previous outputs (i.e. the state), are not equal. Simulation results indicate that by using MAP detection instead of maximum likelihood, gains as high as 0.57 dB and 2.2 dB can be achieved in terms of signal-to-quantization noise ratio (SQNR) for Gauss-Markov source and speech samples, respectively. >