TDMA-Based Cooperative NC MAC Scheme for Two-Way Relaying Networks

In this paper, we study a cooperative network-coding (NC) media-access control for the two-way two-hop relay network specified with several helpers besides a default relay node. The idle helpers can help forward relay packets. The considered protocol focuses on the channel-based time-division multiple access (TDMA) principle and is called a two-way network-coding-based cooperative relaying TDMA (TW-NCCR) protocol. As the main contribution, we analytically derive the throughput performance of TW-NCCR, and further verify it by simulation. Then, we compare it with a two-way cooperative relaying TDMA (TW-CR) protocol, which is the counterpart of TW-NCCR but applies no network coding. Both the theoretical analysis and simulation results demonstrate that TW-NCCR provides superior throughput performance compared with TW-CR, especially when the two-way relay network is symmetric. On the other hand, no matter how weak they are, helpers are able to improve the performance of asymmetric networks using TW-NCCR, especially when the non-reciprocation packet generation rate of the relay node is small.