提出了一种基于分组机制的位仲裁查询树(GBAQT,bit arbitration query tree based on grouping mechanism)算法。该算法根据标签ID自身特征分组,采用3位仲裁位来取代传统1位仲裁识别标签的方式,通过碰撞位信息得到传输数据,从而能避免...提出了一种基于分组机制的位仲裁查询树(GBAQT,bit arbitration query tree based on grouping mechanism)算法。该算法根据标签ID自身特征分组,采用3位仲裁位来取代传统1位仲裁识别标签的方式,通过碰撞位信息得到传输数据,从而能避免一些空闲时隙。算法的性能分析和仿真结果表明,GBAQT防碰撞算法具有较少的总时隙数,系统效率和时隙利用率也明显优于其他算法。展开更多
Recent researches show that inter-session network coding could decrease the number of packets transmission and achieve higher throughput in wireless network compared with traditional forwarding mechanism. In most exis...Recent researches show that inter-session network coding could decrease the number of packets transmission and achieve higher throughput in wireless network compared with traditional forwarding mechanism. In most existing relay mechanisms based on inter-session network such as COPE, relay node demands to collect the messages from its neighbor nodes to get notice of which packets already overheard by them so as to determine whether there exists coding opportunity between or among forwarding packets. However, transmission overhead of this message collection and computing cost of opportunity determination will degrade the performance of these mechanisms. It is observed that coding opportunity at relay node is much more related with the local topology, and the opportunity of encoding three or more packets together is far less than that of encoding two packets together in wireless network with general density. Based on this, a new coding-aware routing mechanism, named TCAR, is proposed. TCAR ignores the oppommity of encoding three or more than three packets together. Each relay node maintains an encoding mapping table being established according to the result of its local topology detection, which can be used to calculate the path cost during routing setup phase, and determine that which two packets can be encoded together during the packets forwarding phase. In TCAR, instead of periodic messages collection, each relay nodes just need once local topology detection, and the encoding determination is much simpler than that of the former mechanisms. Simulation results show that compared with typical inter-session network coding mechanisms COPE and COPE-based routing, TCAR achieves 12% and 7% throughput gains, and keeps the minimum end to end delay.展开更多
文摘提出了一种基于分组机制的位仲裁查询树(GBAQT,bit arbitration query tree based on grouping mechanism)算法。该算法根据标签ID自身特征分组,采用3位仲裁位来取代传统1位仲裁识别标签的方式,通过碰撞位信息得到传输数据,从而能避免一些空闲时隙。算法的性能分析和仿真结果表明,GBAQT防碰撞算法具有较少的总时隙数,系统效率和时隙利用率也明显优于其他算法。
基金Projects(61173169,61106036)supported by the National Natural Science Foundation of ChinaProject(NCET-10-0798)Program for New Century Excellent Talents in University,China
文摘Recent researches show that inter-session network coding could decrease the number of packets transmission and achieve higher throughput in wireless network compared with traditional forwarding mechanism. In most existing relay mechanisms based on inter-session network such as COPE, relay node demands to collect the messages from its neighbor nodes to get notice of which packets already overheard by them so as to determine whether there exists coding opportunity between or among forwarding packets. However, transmission overhead of this message collection and computing cost of opportunity determination will degrade the performance of these mechanisms. It is observed that coding opportunity at relay node is much more related with the local topology, and the opportunity of encoding three or more packets together is far less than that of encoding two packets together in wireless network with general density. Based on this, a new coding-aware routing mechanism, named TCAR, is proposed. TCAR ignores the oppommity of encoding three or more than three packets together. Each relay node maintains an encoding mapping table being established according to the result of its local topology detection, which can be used to calculate the path cost during routing setup phase, and determine that which two packets can be encoded together during the packets forwarding phase. In TCAR, instead of periodic messages collection, each relay nodes just need once local topology detection, and the encoding determination is much simpler than that of the former mechanisms. Simulation results show that compared with typical inter-session network coding mechanisms COPE and COPE-based routing, TCAR achieves 12% and 7% throughput gains, and keeps the minimum end to end delay.
