基于频谱异构和用户移动的频谱共享算法研究

Research on spectrum sharing algorithm based on spectrum heterogeneity and user mobility

频谱共享允许多个认知节点以机会主义方式使用空闲频谱资源,而绝大多数的频谱共享研究没有考虑传输距离、错误率等方面的频谱异构特性。针对集中控制认知无线网络,提出一种基于频谱异构和用户移动的频谱共享算法。网络中不同类型的频谱信道具有不同的覆盖范围,认知用户可以静止或移动。认知用户的信道分配综合考虑了信道可使用时间、用户地理位置、接入公平性等因素,并在此基础上建立了一个信道分配效用函数,最终目的是最大化系统总效用。仿真结果表明,提出的频谱共享算法能够大大减少系统中的信道切换次数,同时系统其他方面的性能也能够得到保证。

Spectrum sharing is envisaged to allow multiple Cognitive Radio（CR） nodes to jointly use the vacant spectrum resource for opportunistic transmission.Most previous work on the spectrum sharing do not take into account the spectrum heterogeneity, such as different transmission ranges, error rates, etc.In this paper, a spectrum sharing algorithm is presented that accommodates spectrum heterogeneity for centralized CR networks.Different types of channels have different transmission ranges and the CR users are static or mobile.Each user is uniquely assigned a channel while considering its channel occupancy time,the location of the user, and the fairness of channel access opporttmity.Based on these metrics l a utility func- tion is employed to allocate channels and the final objective is to maximize the total utility of system.Simulation results reveal significant improvement in reducing spectrum handoffs and other system performances can be guaranteed.