An ARQ Mechanism with Rate Control for Two-Hop Relaying Systems

Wireless multi-hop relaying has been attracting considerable attention as a promising technique for future communication systems. The multi-hop relaying technique has many benefits, but many problems must be overcome if it is to be used successfully. One of the biggest is a degradation of system reliability that is caused by data being transmitted through many wireless links. Many automatic repeat request (ARQ) mechanisms have been proposed to improve system reliability. We propose an analytical model of hop-by-hop ARQ mechanisms and analyze performances using a discrete-time Markov chain (DTMC) technique. The proposed analytical model considers Poisson packet arrival, packet error rate, and channel capacity in a two-hop chain topology. In addition, we propose a rate control algorithm to compensate the weak point of the hop-by-hop ARQ mechanism. We evaluate the performance of the proposed ARQ mechanism with the rate control algorithm by comparing numerical analysis with simulation results.