Highly efficient multi-hop transmission using intra-flow interference cancellation and MRC

CSMA/CA protocol shows poor performance for multi-hop transmission due to intra-flow interference (IFI) caused by hidden terminal (HT) problem. We propose an IFI-cancelling (IFIC) multi-hop transmission scheme which can efficiently relay packets under high traffic load and fading environment by using a Known interference cancellation technique. It employs the least mean square (LMS) equalization process of signal reception. A packet frame format dedicated to the proposed IFIC is designed. Theoretical model and a physical layer-included simulator are created for validation and performance evaluation. The results show that the throughput of the IFIC transmission under Rayleigh fading environment linearly increases with traffic load. When traffic load is high, it has about 3 times higher throughput than the multi-hop network with normal CSMA/CA. When 2-branch maximal-ratio combining (MRC) reception is added after IC, the throughput is further enhanced very close to the theoretical maximum.