智能手持终端GNSS数据解码方式及质量分析

GNSS Raw Data Decoding and Quality Analysis for Smart Phones

手持设备的高精度定位对于各类位置服务及行业应用具有重要意义,利用安卓系统接口可获取GNSS原始观测,从信噪比、完整率、伪距多路径、周跳比这几个技术指标可对数据质量进行评价,选取小米K30智能手机与测量型接收机及工业级接收机进行横向对比。实验结果表明,目前智能手机可以跟踪多系统卫星但只能输出部分卫星的双频数据,卫星数据的信噪比平均值比专业接收机低7 d B左右,数据完整率约为90%左右,开阔环境下的伪距多路径大于1 m,载波相位观测值周跳非常频繁,研究结果为低成本高精度定位算法设计提供了参考。

High-precision positioning of mobile phones has huge application potential.This article uses Android system interface to get the original GNSS observations and evaluate data quality from several technical indicators such as signal-to-noise ratio,integrity rate,pseudo-range multipath and cycle slip ratio.This article selects Xiaomi K30 smart phones and measurement receivers and industrial-grade receivers for horizontal comparison.Experimental results show that the current smart phone can track multi-system satellites but can only output dual-frequency data of some satellites.The average signal-to-noise ratio of satellite data is about 7 dB lower than that of professional receivers,and the data integrity rate is about 90%.In an open environment,the pseudo-range multipath is greater than 1 meter,and the cycle slip of the carrier phase observation value is very frequent.The research results provide a reference for the design of low-cost and high-precision positioning algorithms.