Hybrid error control mechanism for video transmission in the wireless IP networks

Considering the limited bandwidth of the wireless link, it is important that the error control mechanism in wireless networks be spectrally efficient. Towards this end, we develop a hybrid error control architecture which takes into account the use of hierarchical video coding. Additionally, the architecture also includes a module which estimates the packet error rate and round trip time observed by the receiver and adjusts the level of redundancy used based on the estimate. By choosing different options in the architecture, we get different error control schemes. In this paper, we investigate the performance of five different error control schemes, namely ARQ, pure FEC, hybrid FEC/ARQ, hybrid FEC/ARQ with priority-dependent redundancy, and adaptive hybrid FEC/ARQ with priority-dependent redundancy. We evaluate the performance of these schemes using MPEG-2 video traces. The results show that pure FEC offers the worst overall performance. The ARQ scheme offers the best performance under low bit error rate and short round trip time, while the priority-aware hybrid FEC/ARQ with or without FEC adaptation offers the best performance under other conditions.