Multimedia communication over OFDM mobile wireless networks: a cross-layer diversity approach

Diversity can be used to combat multipath fading and improve the performance of mobile wireless multimedia communication systems. In this work, by considering transmission of an embedded bitstream over a slow varying Rayleigh faded environment, we develop a cross-layer diversity technique which takes advantage of both multiple description source coding and frequency diversity techniques. More specifically, assuming a frequency-selective channel, we study the packet loss behavior of an OFDM system and construct multiple independent descriptions using an FEC-based strategy. We demonstrate the superior performance of this approach using the set partitioning in hierarchical trees (SPIHT) coder.