Enhancing video quality for multiple-description MIMO transmission through unequal power allocation between eigen-modes

Promising performance of multiple-description coding (MDC) as a suitable video decomposition for MIMO (multiple-input-multiple-output) wireless transmission, reported previously by a number of authors, is further enhanced in this paper by investigating power allocation in MIMO systems that employ singular value decomposition (SVD). Inspired by the water-filling power allocation strategy, results demonstrate that further improvements over conventional, single-description coding (SDC) are possible if, for low SNRs, stronger sub-channel is boosted at the expense of the weaker channel. For high SNR values, the converse is true. A simple yet effective power allocation strategy whereby the bulk of the transmit power - the highest value considered was nine tenths - was allocated to the stronger channel (weaker channel) for very low (very high) SNRs yielded improvements of up to 4 dB (1 dB) in average MDC PSNR over the nominal - equal power allocation - case. The PSNR gains for low SNR values even exceeded the gains arising from water-filling.