Research On The Subgraph And Code Of Network Coding In Wireless Network

Compared to traditional routing technology, network coding technology can improve theperformances of wireless networks, such as increasing network throughput, providing robustnessagainst packet losses, but at the same time it also increases the calculation and delay of encodingand decoding, which have the bad effect on system. In order to give full play to the advantages ofnetwork coding, this paper research on the subgraph and code of network coding in wirelessnetwork.In this thesis, firstly，the basic concepts of network coding, the advantages and disadvantages ofnetwork coding are introduced. These knowledges are the theoretical foundation for the laterresearch. Secondly, the thesis consider the problem of finding a minimum cost sub-graph based onnetwork coding in wireless network, where delay of each link and limited buffer-size of theintermediate nodes are taken into account. The optimization model is formulated and the distributedalgorithm is proposed. As shown by the simulation results, larger buffer-size of the nodes may leadto cost reduction, and the performance of the system with network coding outperforms thetraditional system. Thirdly, the system of instantly decodable network coding (IDNC) for thesingle-hop wireless broadcast is presented. Aiming at minimizing decoding delay based on IDNC,two algorithms are proposed, and the decoding delay and throughput performance of thesealgorithms are compared through simulation. Finally, a new coding model is introduced under theconsidering of throughput-delay tradeoff in the same scenario. The partitioning algorithm ofsub-generations in this coding framework is optimized, which can obtain the better performance.