基于次用户分级的PRP M/G/m排队论频谱切换模型

为满足次用户不同时延需求并提高信道利用率，该文提出一种基于次用户分级的PRP M/G/m排队论频谱切换模型。首先，根据次用户主要业务的时延需求不同，对次用户进行分级评价，将次用户分为时延敏感型和非时延敏感型用户，时延敏感型次用户具有更高的优先级来接入信道。其次，采用PRP M/G/m排队论来建立基于用户分级的频谱切换模型。同时推导和分析了该模型下不同优先级次用户扩展数据传输时间，进而提出了面向各级次用户自适应频谱切换策略。仿真结果表明，相较于已有频谱切换策略，该模型能有效降低次用户切换时延以及扩展数据传输时间，保证高优先级次用户的服务质量，提升次用户频谱切换的综合性能。

PRP M/G/m Queuing Theory Spectrum Handoff Model Based on Classified Secondary Users

In order to meet different delay requirements of secondary users and improve the channel utilization, a PRP M/G/m queuing theory spectrum handoff model based on classified secondary user is proposed. Firstly, according to different delay requirements of the main service, secondary users are classified into delay-sensitive and non-delay-sensitive users. The delay-sensitive users have higher priority to access the channel. Secondly, PRP M/G/m queuing theory is adopted to establish the spectrum handoff model. Meanwhile, the extended data delivery time of secondary users with different priorities is deduced and analyzed. Then the adaptive spectrum handoff strategy for secondary users is proposed. Simulation results suggest that the proposed model can reduce the handoff delay and extended data delivery time, which can effectively ensure the QoS of high- priority secondary users and improve the overall performance.