Hybrid Erasure-Error Protocols for Wireless Video
Many recently proposed cross-layer protocols for wireless video, have advocated the relay of corrupted packet to higher layers. Such protocols lead to both errors and erasures at the compressed video application layer. We generically refer to such schemes as hybrid erasure-error protocols (HEEPs). In this paper, we analyze the utility of HEEPs for efficient transmission of video over wireless channels. In order to maintain the generic nature of the deductions in this paper, we base our analysis on two (rather abstract) communication schemes for wireless video: hybrid error-erasure cross-layer design (CLD) and hybrid error-erasure cross-layer design with side-information (CLDS). We make a comparative analysis of the channel capacities of these schemes over single and multi-hop wireless channels to identify the conditions under which the HEEPs can provide improved performance over conventional (CON) protocols. In addition, we employ Reed Solomon (RS) and low-density parity check (LDPC)-code-based forward-error correction (FEC) schemes to illustrate that the improvement in capacity can easily enable an FEC scheme employed in conjunction with a HEEP to provide improved throughput. Finally we compare the performance of CON, CLD, and CLDS in terms of video quality using the H.264 video standard. The simulation results show a significant advantage for the HEEPs