一种新的双模微基站非授权信道接入方法

A Novel Dual-band Femtocells Unlicensed Channel Access Mechanism

利用非授权频段频谱资源提升网络容量需要有效地解决LTE(Long Term Evaluation)与Wi Fi的共存问题。最近,学术界和工业界相继提出了授权频段辅助接入机制和双模微基站技术提升蜂窝通信系统容量。考虑双模微基站与Wi Fi接入点覆盖范围存在部分重叠场景,该文提出一种新的双模微基站非授权信道接入机制及联合授权非授权的优化频谱资源分配方案。仿真结果表明,双模微基站和Wi Fi接入点互不可见时,新方案相比于现有方案由于考虑了空间复用具有更好的系统性能;双模微基站和Wi Fi接入点互相可见时,新方案与现有方案性能一致,即两者分时独立占用非授权频段频谱资源。

In order to efficiently utilize the unlicensed band to improve the network capacity, it is necessary to solve the problem of the coexistence between Long Term Evaluation（LTE） and Wi Fi. Licensed-Assisted Access（LAA） and the Dual-Band Femtocell（DBF） which can access both the licensed and unlicensed bands are proposed recently. In this paper, considering the case that a DBF partly overlaps with just one Wi Fi Access Point（AP）, a novel DBF unlicensed channel access mechanism is proposed. Then, the optimal traffic balancing scheme over licensed and unlicensed bands considering the effect of coverage overlap is developed. Numerical results show that if DBF and Wi Fi AP are invisible mutually, the proposed scheme outperforms the existing scheme in terms of sum utility and throughput because of extra fraction of unlicensed channel time for DBF using spatial reuse. Otherwise the performance is the same as the existing scheme, that is, DBF and Wi Fi AP use the unlicensed band alternately.