Performance enhancement in spread spectrum multiple-access networks using hybrid ARQ and hand-shake protocols

The performance of an asynchronous spread spectrum multiple access network under a simple hybrid-automatic repeat request (ARQ) control protocol and a hand-shake protocol is analyzed. The performance under a simple hybrid-ARQ scheme using convolutional encoding and Viterbi decoding with repeat request is presented. The protocol enables the receivers to request retransmission before the decoding process is over. An evaluation is made of a hand-shake protocol without the hybrid-ARQ control. The hand-shake time is assumed to be exponentially distributed. Under the assumptions of uniform traffic with Poisson arrival process and exponentially distributed packet lengths, the network is modeled with several interactive absorbing Markov chains. The performance in throughput and reliability is numerically compared with the pure forward error control (FEC) protocol