MMSE power allocation for image and video transmission over wireless channels

In this paper, a new technique for power allocation to transmitted bits according to their significance on the message quality is presented. The proposed scheme is based on optimizing the power allocation to minimize the mean-square error rather than the bit error probability of image and video signals transmitted over fading wireless channels. An analytical framework for the power allocation technique is developed. Two techniques of power allocation; fixed and adaptive, are investigated in the paper. Simulation results show that the proposed scheme provides a gain of about 3 dB in E_b/N₀ in AWGN channels and about 4 dB in flat fading channels over conventional equal-power allocation system. This gain is achieved without any increase in bandwidth, as opposed to that achieved with channel coding. The gains achieved with this algorithm come at the expense of slight increase in the peak-to-average power ratio of the transmitted signal