基于3GPP协议的毫米波波束跟踪方案设计

3GPP protocol based beam tracking scheme design for millimeter wave communications

波束跟踪是5G毫米波通信系统保持无线链路稳定性的重要技术之一。基于3GPP协议规定的下行波束管理过程P1、P2、P3和上行波束管理过程U1、U2、U3,详细分析和对比了不同波束跟踪方案的资源占用率与波束失败概率。分析与仿真结果表明,从平均资源占用率的角度来看,由于一般通信系统中下行资源往往比较丰富,因此P2+P3方案相对最优;从波束失败概率的角度来看,由于U2+P3方案无需功率反馈,因此波束失败的概率最低。在实际通信系统中,可根据具体的指标要求,选用合理的波束跟踪方案。

Beam tracking is one of key technologies of millimeter wave communication systems for maintaining a stable radio link.Based on the downlink beam management procedure P1,P2,P3 and uplink beam management procedure U1,U2,U3 specified in 3GPP(3rd Generation Partnership Project)protocols,this paper analyzes and compares the resource occupation rate and beam failure probability of different beam tracking schemes.Analysis and simulation results show that the P2+P3 scheme is optimal in the sense of average resource occupation rate as the downlink resource is usually abundant in general,whereas,in the sense of beam failure probability,the U2+P3 scheme is optimal since it is free of power information feedback.In practice,an appropriate beam tracking scheme can be chosen according to the special communication requirements.