Publications:Packet combining and doping in concatenated hybrid ARQ schemes using iterative decoding

Jump to: navigation, search

Do not edit this section

Keep all hand-made modifications below

Title Packet combining and doping in concatenated hybrid ARQ schemes using iterative decoding
Author Elisabeth Uhlemann and Tor M. Aulin and Lars K. Rasmussen and Per-Arne Wiberg
Year 2003
PublicationType Conference Paper
HostPublication The IEEE Wireless Communications and Networking, 2003. WCNC 2003. 2003 IEEE
Conference The IEEE Wireless Communications and Networking Coneference, 20-20 March, New Orleans, LA, USA
Diva url
Abstract We consider serially concatenated block codes in a hybrid ARQ scheme using iterative decoding. The extrinsic information generated in the iterative decoding process is saved and used when a retransmission is decoded. Two different strategies are examined; one using the extrinsic information only in the very first iteration, whereas the other uses it in all subsequent iterations until another retransmission arrives. The latter can be seen as turbo or concatenated code combining whereas the former, where the extrinsic information is used only once may be seen as code doping, providing an alternative perspective. The strategy of saving the extrinsic information is also compared to traditional type-III, equal gain diversity combining. Using the extrinsic information from previous retransmission is shown to improve performance not only in terms of bit error rate but also in terms of throughput and convergence speed and requires only negligible additional decoder complexity. The performance of this strategy is however not as good as simple equal gain combining. As a consequence, the investigated schemes are not competitive alternatives, however, the code doping procedure can be used in conjunction with traditional diversity combining schemes, improving further on convergence speed.