Increasing Robustness of Network Coding Using Non-Orthogonal Decode-and-Forward Protocol

This paper investigates the effect of non-orthogonal decode-and-forward (NDF) relaying scheme in wireless network coding environments. It is well known that network coding is effective to improve overall network performance, but because of error propagation, it may not be always advantageous under a hostile wireless channel. To mitigate error propagation, we adopt NDF relaying scheme in wireless network coding, which allows the source to keep on transmitting the same signal when the relay cooperates to forward the network-coded signal. By NDF relay scheme, SNR of the link between source and destination nodes can be increased, which results in reduced number of errors through the link. Simulation results show that network coding with NDF relay scheme average packet error rate performance as well as goodput in wireless butterfly network.