Radio hardware used for the reception of 802.11b frames is capable of associating a Signal to Silence Ratio (SSR) with each received frame. If a received frame is corrupted, then these SSR indications can be used to provide robust apriori estimate of the bit error rate in the packet. In many recently proposed cross-layer protocols, for transmission of video over wireless networks, recovery of information from partially corrupted packets has shown significant utility. In this paper, based on experiments with actual 802.11b error traces, we show that the Channel State Information (CSI) provided by the SSR indications can be used to improve the error recovery performance of an FEC scheme employed in conjunction with a cross-layer protocol. H.264 based simulation are used to establish the efficacy of the proposed work for video applications; specifically for video over 802.11b WLAN.
Shirish S. Karande, Utpal Parrikar, Kiran Misra, H