A Practical Hybrid-ARQ Protocol Using Noncoherent Orthogonal Modulation

Abstract

This paper considers hybrid-ARQ under the constraints of noncoherent orthogonal modulation and hard-decision decoding. Information theoretic bounds on the throughput for such systems are derived. A practical coding technique based on Reed-Solomon codes is proposed and analyzed. The proposed hybrid-ARQ protocol is modified to allow relay nodes to service retransmission requests. The proposed protocol is suitable for IEEE 802.15.4/Zigbee networks using commodity off-the-shelf hardware.