CR-RSMA网络接入控制策略研究

Research on access control strategy for a CR-RSMA network

针对多个次用户的速率分割多址接入技术辅助的认知无线电(CR-RSMA,cognitive radio-inspired rate splittingmultipleaccess)网络设计了一种接入控制策略,在主用户实现与正交多址接入(OMA,orthogonal multiple access)相同的中断性能并满足次用户通信服务质量(QoS,quality of service)需求的前提下,让更多的次用户接入主用户频段,并在此基础上最大化次用户吞吐量之和。该策略考虑次用户QoS约束,联合优化次用户发射功率分配因子和接入次用户集合,推导出最优功率分配因子的闭合表达式,进而求得次用户最大通信速率和最小通信时间,在此基础上利用贪婪搜索算法确定最终接入的次用户,最后通过优化时间资源实现所有接入次用户吞吐量之和的最大化。仿真结果表明,该策略相比于非正交多址接入技术辅助的认知无线电(CR-NOMA,cognitive radio-inspired non-orthogonal multiple access)网络在接入用户数和吞吐量方面均表现出更优越的性能。

An access control strategy was designed for the cognitive radio-inspired rate splitting multiple access(CR-RSMA)network with multiple secondary users.This strategy aimed to enable more secondary users to access the primary user′s frequency band while ensuring that the primary user achieved the same outage performance as orthogonal multiple access(OMA)and satisfying the quality of service(QoS)requirements for communications of secondary users.The sum throughput of secondary users were maximized on this basis.Considering the QoS constraints of secondary users,the strategy jointly optimized the secondary users′transmit power allocation factor and the set of accessible secondary users,and derived the closed-form expression of the optimal power allocation factor.Then,the maximum communication rate and minimum communication time of secondary users were obtained.Building upon this,the greedy search algorithm was employed to determine the final set of accessed secondary users.Finally,the strategy optimized time resources to maximize the sum throughput of all admitted secondary users.Simulation results demonstrate that the proposed strategy outperforms the cognitive radio-inspired non-orthogonal multiple access(CR-NOMA)network in terms of the number of accessible users and throughput.