A framework for joint multiple description coding and network coding over wireless ad-hoc networks

Network coding (NC) can achieve the maximum information flow in the network by allowing nodes to combine received packets before retransmission. Several papers have shown NC to be beneficial in mobile ad-hoc networks, but the delay introduced by buffered decoding raises a problem in real-time streaming applications. Here we propose to use NC jointly with multiple description coding (MDC) to allow instant decoding of the received packets. The optimal encoding coefficients are chosen via distributed optimisation of the expected video quality. Nodes receive up-to-date information about the network topology through a recently proposed protocol, originally designed for real-time streaming of MDC video. Results show that, due to the limitations imposed by instant decoding to the coding window size, our approach consistently outperforms the popular technique of random linear network coding.