The cooperative multicasting based on random network coding in wireless networks

Random network coding (RNC) is an efficient coding scheme at the network layer to improve the performance of the wireless multicast networks. However, the full set of encoded packets may not be collected to correctly decode the original information in wireless fading channels, leading to the low network throughput. This issue will be more severe in multimedia transmission. On the other hand, cooperative transmission scheme that fully utilizes the space diversity can effectively mitigate channel impairments. Accordingly, we proposed an all-user cooperation scheduling scheme based on the adaptive random network coding to improve the transmission efficiency in wireless networks with fading channels. The cooperative and adaptive random network coding (CARNC) scheme schedules one user as a relay to help the transmitter by maximizing the immediate network throughput based on the packet reception status of all users. This cooperation can effectively repair the encoded packet set due to deep channel fading and improve the throughput of the whole network. Extensive simulations have been conducted to evaluate and compare the performance of the proposed CARNC and other scheduling schemes. The results have shown that CARNC has a better performance in the whole network throughput due to the utilization of both adaptive coding and user cooperation.