Forward error correction with physical layer network coding in two-way relay free space optical links

Physical layer network coding (PNC) is a promising technique to improve the network throughput in a wireless two-way relay (TWR) channel. The PNC is embraced for TWR with free space optical (FSO) communication link, TWR-FSO, for full utilization of network resources. In this paper, forward error correction (FEC) is employed with TWR-FSO PNC system. The convolutional code (CC) is considered to combat the deleterious effect of FSO turbulence channel to increase the system reliability. The performance of end-to-end (E2E) CC with TWR-FSO PNC scheme is examined in terms of bit error rate (BER) under the influence of turbulence-induced channel fading. The results show that the proposed scheme can achieve a significant BER performance improvement through the introduction of CC joint with PNC mapping, which enables the system to effectively mitigate the impact of channel.