Performance Analysis of Multihop-Diversity-Aided Multihop Links

A multihop transmission scheme is proposed and studied, where all the relay nodes (RNs) of a multihop link are assumed to have buffers for temporarily storing their received packets. Hence, the RNs are operated under the so-called store-and-forward relaying scheme. As a benefit of storing packets at the RNs, during each time slot, the best hop typically has the highest signal-to-noise ratio (SNR), which can be selected from the set of hops that have packets awaiting transmission in the buffer. A packet is then transmitted over the best hop. This hop selection procedure is reminiscent of selection diversity, which is referred to here as multihop diversity (MHD). In this paper, we investigate both the bit error and outage probability and the delay performance of the MHD scheme when assuming that each hop experiences both propagation path loss and independent and identically distributed (i.i.d.) flat Rayleigh fading. The medium access control (MAC) layer implementation and several closed-form formulas are derived. Both numerical and simulation results are provided to characterize the achievable performance of the MHD scheme. Our performance results show that relying on multiple hops has the potential to provide a significant diversity gain, which may be exploited for enhancing the reliability of wireless multihop communications.