该文结合机会式频谱共享(Overlay)与共存式频谱共享(Underlay)提出一种混合式频谱共享模型。基于提出的模型,考虑次用户理想感知和非理想感知两种情况,采用离散状态马尔科夫过程对信道活动进行建模,进而在平均容量最大化准则下分析了混合式频谱共享系统的功率分配问题,导出了次用户的最优功率分配策略及系统可获得的最大容量。理论和仿真结果表明,基于最优功率分配策略的混合式频谱共享系统可以获得比Overlay或Underlay系统更高的容量。
This paper proposes a hybrid spectrum sharing model which combines Overlay with Underlay.Based on the proposed model,considering of perfect and imperfect spectrum sensing,it models the channel activity with discrete-state Markov process.Furthermore,under the criterion of maximizing the system average(ergodic) capacity,it analyzes the power allocation of the hybrid spectrum sharing and deduces the optimal power allocation scheme as well as the maximum achievable capacity of the system.Analysis and simulation results indicate the hybrid spectrum sharing is provided with higher capacity than single Overlay or Underlay system.