【摘要】 为了降低因LTE系统中布设毫微微小区(家庭基站)而给宏小区用户带来的干扰,采用在毫微微小区中引入认知无线电技术的方法,构建了一种混合式频谱接入模型.毫微微小区通过周期性地感知其无线环境,使之择机接入可用的频段,从而智能地使用频谱资源.对频谱感知分为2个阶段,即对宏小区下行链路的主感知和对相应上行链路的辅助感知,基于它们得到的信息,毫微微小区可以灵活地以见缝插针模式或以叠加模式利用频谱.仿真结果表明,在对宏小区的干扰约束限制下,所构建的模型能够带来吞吐量的提升.更多还原

【Abstract】 In order to mitigate the interference for macrocell users caused by deploying femtocells (home base-station) in a long term evolution (LTE) system, a hybrid spectrum access model is proposed by means of applying the cognitive radio technology to the femtocell. The femtocell periodically senses the radio environment and opportunistically accesses the usable frequency band so that the frequency spectrum resource is used intelligently. The sensing process is performed in two stages, which are principal sensing in the downlink and assisted sensing in the uplink, respectively. Based on the information obtained from the sensing results, the frequency spectrum can be used flexibly in underlay or overlay modes in the femtocell. Simulation results show that by using the proposed model, the throughput of a femtocell is greatly improved with tolerable interference to macrocell users.更多还原