Soft-input arithmetic decoding for optimized scalable image transmission over a realistic MIMO channel

In this paper, we investigate a new communication strategy for embedded image transmission over a realistic Multiple-Input Multiple-Output (MIMO) wireless channel. The objective of our approach is to guarantee Quality of Service (QoS) required by the user for all possible channel states. In this scope, two major improvements are considered. The first is based on Unequal Power Allocation (UPA) and aims at optimizing the transmit power over the different antennas in order to maximize the image quality at the reception. The second contribution is based on Joint Source-Channel (JSC) soft-input arithmetic decoding and helps to decrease the error rates at the reception without including extra redundancy. We considered Robust SPIHT (R-SPIHT) source encoder to generate an embedded bit-stream. Simulation results illustrate good image quality improvements at the receiver side, with significant Peak Signal to Noise Ratio (PSNR) gains, especially for a realistic noisy channel provided by a 3D ray-tracing software.