不同电离层模型对智能手机实时PPP精度的影响分析

Influence of Different Ionospheric Models on the Location Accuracy of Smart Phones Real-Time PPP

为了提高智能手机的实时定位精度,对广播星历电离层模型和国际GNSS服务(International GNSS Service,IGS)机构实时发布的球谐电离层模型进行比较分析,并将其作为电离层约束应用到智能手机非差非组合实时精密单点定位(precise point positioning,PPP)中。在静态开阔条件下,使用小米Mi 8和华为Mate 40 Pro智能手机开展试验,结果表明,Mi 8手机的平面精度可达到0.53 m,高程精度可达0.43 m;Mate 40 Pro手机的平面精度可达1.05 m,高程精度可达1.60 m。两种电离层模型的精度存在一定的差异,在滤波算法中,通过设置合理的先验噪声,均可有效提高定位精度和缩短滤波收敛的时间,球谐模型的定位精度要优于广播星历电离层模型。

To improve the real-time positioning accuracy of smart phones,two real-time global ionospheric models,in⁃cluding broadcast ephemeris ionospheric model and spherical harmonic ionospheric model broadcast by IGS(International GNSS service),are compared and analyzed.In this paper,the two models are applied to the undifferenced and uncom⁃bined real-time precise point positioning of smart phones.The experiments are carried out with Xiaomi Mi 8 and Hua⁃wei Mate 40 Pro under static open conditions.And the result shows that the plane accuracy of Mi 8 mobile phone can reach 0.53m and the elevation accuracy can reach 0.43 m;the plane accuracy of Mate 40 Pro mobile phone can reach 1.05m and the elevation accuracy can reach 1.60 m.There are cer⁃tain differences of accuracy between two ionospheric models.By setting appropriate noise in the filtering algorithm,the po⁃sitioning accuracy can be effectively improved and the conver⁃gence time can be shortened,and the spherical harmonic mod⁃el has better positioning accuracy than broadcast ephemeris ionospheric model.