Throughput performance of Hybrid ARQ schemes with packet and code combining for DS‐CDMA downlink systems using orthogonal spreading sequences
Hatem Boujemâa, M. Wissem El Bahri, Mohamed Siala · European Transactions on Telecommunications · 2007
Abstract In this paper, we evaluate the throughput performance of Automatic Repeat reQuest (ARQ) and HARQ I, with packet combining, and HARQ II, with code combining, using convolutional codes for DS‐CDMA downlink systems employing a Rake receiver. The different user packets are code multiplexed using a set of orthogonal variable spreading factor sequences. The analysis is carried out in two extreme scenarios, with either a constant or a packet‐by‐packet independent multipath fading channel during the different transmissions. The obtained results are valid for any multipath intensity profile of the channel and take simultaneously into account AWGN noise, path gains estimation noise, intersymbol interference and multiuser interference. Copyright © 2008 John Wiley & Sons, Ltd.