An optimum block coded modulation scheme for vector quantization communication system

Abstract

A new block coded modulation (BCM) scheme for a PCM communication system which uses the optimum vector quantizer (VQ) as a source coder is proposed. The proposed BCM scheme minimizes the mean square distortion of the received signal after VQ decoding. First, the paper derives the upper-bound on the mean square distortion of the signal in additive white Gaussian noise (AWGN) and Rayleigh fading channels. Next, the paper proposes a new BCM scheme which is optimized to minimize the upper-bound by the simulated annealing known as the non-linear global optimization algorithm. The paper provides the optimum BCM and shows the mean square distortion performances in the AWGN and Rayleigh fading channels. Computer simulation results show that using the proposed BCM improves the signal-to-noise ratio (S/N) performances of the output signal of the source decoder. Furthermore, the proposed BCM scheme can provide a stepwise graceful degradation in the output S/N performance against the channel S/N.