Directional geographical routing for real-time video communications in wireless sensor networks

In this paper, we address the problem of real-time video streaming over a bandwidth and energy constrained wireless sensor network (WSN) from a small number of dispersed video-sensor nodes (VNs) to a sink by combining forward error correction (FEC) coding with a novel multipath rouing scheme called directional geographical routing (DGR). DGR constructs an application-specific number of multiple disjointed paths for a VN to transmit parallel FEC-protected H.26L real-time video streams over a bandwidth-limited, unreliable networking environment. The multiple paths in DGR facilitate load balancing, bandwidth aggregation, and fast packet delivery. Extensive simulation experiments over randomly generated WSNs show that DGR has the following advantages: (i) lower delay, (ii) substantially longer network lifetime, and (iii) a better received video quality. In particular, DGR improves the average video peak signal-to-noise ratio (PSNR) by up to 3dB, compared to a traditional geographic routing scheme. (c) 2007 Elsevier B.V. All rights reserved.