Throughput performance of a class of continuous ARQ strategies for burst-error channels

The throughput performance of a class of continuous automatic repeat request (ARQ) strategies for burst-error channels modeled by two-state Markov chains is studied. The operation of the investigated ARQ strategies can be described as follows. A chunk of m or fewer copies of each data block is transmitted contiguously to the receiver. Whenever a repeat request is received, the transmitter goes back to and retransmits that data block and all successive ones. However, the maximal number of copies transmitted is equal to n in each retransmission. It is proved that the optimal repetition sequence which maximizes the throughput efficiency among a more general set of ARQ schemes falls in the class of investigated strategies. Numerical results reveal that throughput efficiency is very likely to be maximized at m=n