基于OTDOA的5G定位性能综合分析

Comprehensive Analysis of 5G Positioning Performance Based on OTDOA

介绍了5G定位服务的性能需求,分析了1个时隙内的PRS结构,并从PRS带宽(N_(BR)^(RPS))、梳齿尺寸(K_(comb)^(PRS))、符号数(L_(PRS))、周期(T_(per)^(PRS))和重复因子(T_(rep)^(PRS))等方面给出了PRS参数的配置原则。最后给出了基于PRS的OTDOA距离估计的CLRB评价算法,理论上,随着SNR和带宽的增加,OTDOA距离估计的CLRB可以非常小,但是由于多径和NLOS传播、网络同步误差等因素,OTDOA的定位精度比CLRB要至少低2个数量级,因此OTDOA定位应与GNSS等定位技术结合起来以便增加定位精度,满足5G定位服务的性能需求。

It introduces the performance requirements of 5G positioning services,and analyzes the structure of PRS within one solt and offers the configuration principle of PRS parameters,including PRS bandwidth(N_(BR)^(RPS)),comb size(K_(comb)^(PRS)),symbol numbe(r L_(PRS)),periodicity(T_(per)^(PRS))and repetition factor(T_(rep)^(PRS)).Finally,a CLRB algorithm for OTDOA distance estimation based on PRS is proposed.In theory,the CLRB for OTDOA is very small with the increase of SNR and bandwidth.When comparing the CLRB,OTDOA positioning accuracy is decreased by more than two orders of magnitude due to multipath and NLOS propagation,network synchronization error.So OTDOA positioning should be combined with other positioning technologies such as GNSS to increase positioning accuracy and meet performances of 5G positioning services.