基于碰撞概率约束的认知系统子信道分配算法

Subcarrier allocation algorithm of CR system based on collision probability constraints

针对如何在保护主用户的同时最大化有效吞吐量的子信道分配问题,考虑由于主用户的重新到来而造成的主次用户碰撞,给出一种基于子信道碰撞概率约束的子信道分配算法。算法通过约束子信道碰撞概率来保护主用户,依据碰撞概率约束估计各子信道可容忍最大传输时长,随后认知用户根据请求业务时长选择合适的子信道接入。仿真结果表明,与不考虑子信道碰撞概率约束的算法相比,该分配算法很好地保护了主用户,且在信道条件较好时,能取得更好的有效吞吐量性能。

In order to maximize the effective throughput while protecting the primary user, a subchannel allocation algorithm based on the subchannels collision probability restraints is proposed by considering the collision between primary user and cognitive user caused by primary user＇s return. The proposed algorithm protects the primary users by constraining the subchannels collision probability, and the maximum transmission delay that each subchannel can tolerate is estimated by the probability of collision restraints. The appropriate subchannel is selected according to the cognitive user＇s service. Simulation results show that the allocation algorithm can protect the primary users well, and can achieve better throughput performance under better channel conditions, compared to the algorithm without considering the constraints of the subchannel collision probability.