低成本GNSS终端多普勒平滑伪距定位算法

Low cost GNSS terminal Doppler smoothing pseudorange positioning algorithm

随着低成本全球卫星定位(GNSS)终端硬件性能的不断提升,其在定位领域的应用也更加广泛,然而低成本GNSS终端在数据采集中常受观测环境的影响,使得载波相位观测值的高精度定位较为困难。伪距定位算法因其定位模型简单且实时性好的优势被广泛使用,因此本文利用多普勒平滑伪距方法,充分利用了多普勒观测值的作用,通过多普勒平滑伪距噪声来提升观测值的测量精度,利用多普勒平滑伪距模型对静态与多种动态环境下的平滑效果进行测试和分析。实验结果表明:在静态情况下,采用多普勒平滑伪距算法,伪距单点定位与伪距实时差分定位模型定位中平面精度较平滑之前分别提高了25%与31%;在动态环境下,有遮挡动态实验其精度提升30%以上,空旷情况下定位精度提升15%以上,快速运动过程中其提升能达到20%左右。表明通过多普勒平滑伪距算法可以显著提高低成本GNSS终端的定位精度。

With the continuous improvement of the hardware performance of low-cost GNSS(Global Navigation Satellite System)terminals,their applications in positioning have become more widespread.However,low-cost GNSS terminals are often affected by the observation environment in data acquisition,making high-precision positioning of carrier phase observations more difficult.Pseudorange positioning algorithms are widely used due to their advantages of simple positioning models and good real-time performance.Therefore,this article usecl the Doppler smoothing pseudorange method,fully utilizing the role of Doppler observations,and the measurement accuracy of observations was improved through Doppler smoothing pseudorange noise.The Doppler smoothing pseudorange model was used to analyze the smoothing effect in static and various dynamic environments.The experimental results showed that in static conditions,using the Doppler smoothing pseudorange algorithm,the planar accuracy of SPP(standard point positioning)and RTD(real time differential)had improved by 25%and 31%,respectively,compared to the results before smoothing.In dynamic environments,the accuracy of dynamic experiments with occlusion could be improved by more than 30%,and in open conditions,the positioning accuracy could be improved by more than 15%.During rapid motion,the improvement could reach about 20%.The experimental results showed that the Doppler smoothing pseudorange algorithm loald significantly improve the positioning accuracy of low-cost GNSS terminals.