Abstract: For the problem of cross subframe interference caused by the use of dynamic subframe configuration in Long Term Evolution in Unlicensed band (LTE-U) system, a hybrid dynamic clustering algorithm which considered large-scale loss and cell traffic volume was proposed. Firstly, the information of large-scale loss and cell traffic volume was periodically measured by base station, then the corresponding relevance metric value was calculated. Secondly, according to the relevance metric value, the cells were clustered by polling to realize periodic update of clustering result. Finally, the dynamic subframe configuration was performed according to the updated cell clustering result. Simulation results showed that compared with the traditional static clustering algorithm in the medium traffic arrival rate conditions, the uplink-downlink user average throughput of hybrid dynamic clustering algorithm was increased by about 16.92% and 34.33%, the uplink-downlink user average delay was decreased by about 14.18% and 36.32%. Simulation results demonstrate that the hybrid dynamic clustering algorithm can effectively reduce the impact of cross subframe interference, and improve system throughput, which has better performance compared to the traditional static clustering algorithm.

Key words: unlicensed band, Licensed Assisted Access (LAA), dynamic subframe configuration, dynamic clustering, system-level simulation

摘要： 针对非授权频段长期演进（LTE）系统中动态子帧配置引起的交叉子帧干扰问题，提出了一种综合考虑大尺度损耗及小区业务量情况的混合动态分簇算法。首先，通过基站端对大尺度损耗及小区业务量情况的周期性测量，计算出对应的相关度值；然后，根据相关度值对小区进行轮询式分簇，实现小区分簇结果的周期性更新；最后，根据更新后的小区分簇结果执行动态子帧配置。仿真实验中，相比传统的静态分簇算法，中业务到达率条件下混合动态分簇算法的用户上下行平均吞吐量分别提升了约16.92%和34.33%；用户上下行平均时延分别降低了约14.18%和36.32%。仿真结果表明，混合动态分簇算法可以有效减小交叉子帧干扰的影响，提升系统吞吐量，性能优于传统的静态分簇算法。

关键词: 非授权频段, 授权型辅助接入, 动态子帧配置, 动态分簇, 系统级仿真