中继蜂窝网络中增强型随机接入算法

Enhanced Random Access Strategy for Relay Based Cellular Networks

提出一种适用于蜂窝中继网络的增强型随机接入算法。为了保证不同用户的QoS需求,实时业务通过提前预约随机接入信道(Random Access Channel,RACH)实现无冲突的接入,而非实时业务则利用中继节点通过共享剩余的随机接入信道实现两跳接入。为了解决非实时业务在时域接入发生碰撞的问题,中继节点根据当前的非实时业务到达状况和剩余的RACH信道数目,综合地确定所采取的退避策略以及最佳频域退避窗口大小。理论分析和实验仿真表明,该算法能更好地保证非实时业务的接入过程,进一步提高了接入资源的利用率。

this paper presents an enhanced random access strategy to address the issue of random access of the Non-Real-Time（NRT） services in the relay based cellular networks.To guarantee user＇s QoS requirements,NRT services will access the Base Station（BS） by first access the nearest Relay Node（RN）.In odder to deal with the collision problem,the NRT services will begin a frequency domain retry rather than time domain backoff.Meanwhile,according to the new arrival rate as well as the number of available access channels,RN will jointly determine the backoff policy as well as the best frequency backoff window at each access period.The analyses and numerical results demonstrate that our strategy achieves better performances and higher throughput compared with conventional schemes.