We study the design of index assignment based multiple description quantizers for multiple-antenna systems with slow Rayleigh fading. A time-interleaver is employed at the transmitter to provide independent channel instances for the multiple descriptions, and a maximum a posteriori (MAP) detector is employed at the receiver to jointly decode the multiple descriptions. The concatenation of index assignment, binary phase-shift keying modulators, space-time orthogonal block coder, multiple-antenna channel, and MAP detector is modeled as a discrete memoryless channel. We optimize multiple description vector quantizers using an upper bound of the channel transition probability achieved by the MAP detector. The proposed scheme of combining multiple description coding and space-time orthogonal block coding is shown to be superior to each individual coding scheme.

We study the design of multiple description quantizers for space-time orthogonal block coded slow Rayleigh fading channels. A time-interleaver is employed at the transmitter to provide independent channel instances for the multiple descriptions, and a maximum a posteriori (MAP) decoder is employed at the receiver to jointly decode the multiple descriptions. We propose a scheme to optimize multiple description vector quantizers using an upper bound of the channel transition probability achieved by the MAP decoder. The scheme furnishes substantial performance gain.

Conventional multiple description vector quantizers (MDVQ) have high complexity, which limits their practical application. Two central-codebook-constrained MDVQ (CMDVQ) schemes are proposed to reduce the storage and search complexity. Simulation results show that for low channel loss rates, a tradeoff exists between choosing CMDVQ for its low complexity and the conventional MDVQ for its higher signal-to-noise ratio (SNR) performance. For medium to high channel loss rates, CMDVQ is preferred for its low complexity and comparable SNR performance to the conventional MDVQ

We examine the performance of multiple descriptions coding (MDC) with and without the use of automatic retransmission request (ARQ) protocols for packet network communication. The rate-distortion lower bound of MDC and layered coding (LC) are incorporated into a performance measure that accounts for the additional costs of excess rates and delay incurred from using ARQ. Results show that unaided MDC is the best for large packet loss rates and large delay, and LC is the best for small loss and moderate delay. In between these two extremes, MDC aided by ARQ provides the best performance