Space–time efficient network coding for wireless multi-hop networks

Network coding has been recently proposed as a new promising technique that can potentially improve the performance of a wireless multi-hop network significantly. However, most existing studies in this field perform network coding without considering the interplay between transmission power/rate and network coding gain. In many scenarios, the selection of the transmission power/rate brings big impact on network coding gain and consequently network throughput because they have big impact on both reception/overhearing probability and spatial reuse. Therefore, how to improve network throughput by appropriately exploiting the interplay between transmission power, data rate, and network coding gain via localized network operations has been a crucial issue in a multi-hop wireless network. That is, how to achieve a good trade-off between the space–time network resource usage (represented by level of spatial reuse and transmission time) and the network coding gain? To address this problem, in this paper, we propose a decentralized network coding aware power/rate control mechanism, which can enable each node to adjust its transmission power and data rate such that the space–time resource usage is optimized. Extensive simulation results show that the proposed mechanism yields higher performance in network throughput as compared with existing mechanisms.