Effectiveness of copy-transmission in Go-Back-N ARQ system with selective repeat in intra-block and with limited retransmissions

In this paper, we consider the effectiveness of copy-transmission for a class of Go-Back-N ARQ scheme with block of multiple frames and with limited number of retransmissions (M). The retransmitted block is consisted from multiple-copies (C) of each requested frame. Based on the exact formulas of the probability generating function of slots needed to transmit a block and numerical examples, it is shown how to determine C and M for maximizing the throughput and minimizing the average transmission delay of a block within a specified tolerable value of unrecovered frame error rate.