Perceptually enhanced ARQ for live video streaming over congested 802.11e networks

In this paper we present a perceptual ARQ algorithm specifically designed for real-time 802.11 video communications. A fundamental characteristic of the algorithm is its ability to take into account the perceptual and temporal importance of each packet at the same time. A priority value is associated to each packet to determine which one to retransmit at each retransmission opportunity. Compared to the standard 802.11 MAC-layer ARQ scheme, the proposed technique delivers higher perceptual quality because only the most perceptually important packets are retransmitted. Simulations of H. 264 live video streaming in a realistic 802.11e infrastructured scenario show that the proposed method consistently out-performs the standard link-layer 802.11 retransmission scheme, delivering gains up to 10 dB of PSNR as well as very low transmission delays.