Utility-Aware Network Coding in Wireless Butterfly Networks

This paper investigates the effect of combined network coding and power control based on network utility under wireless butterfly networks. Although it is well known that network coding improves network performances, it might not be always advantageous for a hostile wireless environment due to error propagation problem through relaying. Therefore, in this paper, the crossover point for profit-and-loss of network coding and non-network coding according to wireless link quality is derived, and then we show that network utility in terms of spectral efficiency per power is improved, and average power consumption is reduced by adaptively applying relay mode control and power control, which is of bang-bang type with a threshold in wireless butterfly networks.