Network Coding-Based Retransmission for Relay Aided Multisource Multicast Networks
1 School of Engineering & Computing, Glasgow Caledonian University, Cowcaddens Road, Glasgow G4 0BA, UK
2 Signal Processing Laboratory, ACCESS Linnaeus Center, KTH Royal Institute of Technology, 100 44 Stockholm, Sweden
3 School of Electronics and Information, Kyung Hee University, Yongin, Gyeonggi-do 446-701, Republic of Korea
EURASIP Journal on Wireless Communications and Networking 2011, 2011:643920 doi:10.1155/2011/643920Published: 10 March 2011
This paper considers the reliable transmission for wireless multicast networks where multiple sources want to distribute information to a set of destinations with assistance of a relay. Basically, the reliability of a communication link is assured via automatic repeat request (ARQ) protocols. In the context of multisource multicast networks, the challenge is how to retransmit the lost or erroneous packets efficiently. In traditional approaches, the retransmission of lost packets from a single source is treated separately, and thus it may cause a considerable delay. To solve this problem, we propose the relay detects, combines, and forwards the packets which are lost at destinations using network coding. In the proposed ARQ protocol, the relay detects packets from different sources and combines the lost packets using NC. In particular, two packet-combination algorithms are developed to guarantee that all lost packets are retransmitted with the smallest number of retransmissions. Furthermore, we analyze the transmission bandwidth and provide the numerical results to demonstrate the superior performance of the proposed ARQ protocol over some existing schemes.