智能手机GNSS观测数据筛选方法及精度分析

GNSS observation data filtering method and accuracy analysis for smartphones

通过分析智能手机的信噪比波动特性,提出将截止信噪比与剔除数据占比相结合进行数据筛选的质量控制方法,通过设置不同的数据筛选方案,对小米8和华为Mate 20智能手机在静态、动态观测中采集的数据进行对比分析。实验结果表明:智能手机端不同卫星的信噪比波动周期和范围均不同,存在独立性,且高度角和信噪比的相关性弱于测量型接收机,因此根据截止信噪比来筛选数据更为合理。设置截止信噪比的剔除数据占比在5%~10%,对智能手机的定位精度提升最佳,此时截止信噪比约为25 dB-Hz。相比传统设置15°卫星截止高度角的方法,所提方法的东、北、天向精度在静态中约提升25%、10%和20%,动态中约提升30%、20%和5%。

By analyzing the fluctuation characteristics of the signal to noise ratio(SNR)of smart phones,a quality control method combining the cut-off SNR and the proportion of excluded data for data screening is proposed.By setting different data screening schemes,data collected in static and dynamic observations were compared and analyzed through the Xiaomi Mi 8 and Huawei Mate 20 smartphones.The experimental results show that the SNR fluctuation cycle and range of different satellites on the smartphone side are different,there are independence,and the correlation between the high angle and the SNR is weaker than the measured receiver.Therefore,filtering data based on the cutoff signal to noise ratio is more reasonable.The proportion of data excluding data to settle the SNR is about 5%-10%,which increases the best positioning accuracy of smartphones.Currently,the deadline SNR ratio is about 25 dB-Hz.Compared with the traditional setting of the 15°satellite cut-off elevation,the E,N,U accuracy of the method mentioned increased by 25%,10%,and 20%in the static,and the dynamics increased by 30%,20%,and 5%.