无线电工程

未来10年，国内外预计将发射上万颗低轨卫星，地面终端可接收几十颗低轨卫星信号，鉴于低轨卫星良好的多普勒观测性，为手机直连卫星并进行瞬时多普勒定位提供了理想的外在环境条件。从实际工程应用出发，提出了一种低轨卫星机会信号多普勒定位处理方法，推导分析了低轨卫星机会信号多普勒定位数学模型，给出了低轨卫星机会信号多普勒定位算法流程，基于Iridium Next、Starlink、OneWeb、Orbcomm、Globalstar在轨卫星两行轨道根数(Two Line Elements, TLE)数据进行了仿真验证，结果表明在理论无误差情况下多普勒定位精度误差不到1 m;当地面接收机时间精度为1.0 ms、多普勒测量精度为0.2 Hz时，多普勒定位精度三轴误差在米量级。

In the next 10 years, it is expected that tens of thousands of low earth orbit satellites will be launched both domestically and internationally. At that time, ground terminals can receive signals from dozens of low earth orbit satellites. Given the excellent Doppler observability of low earth orbit satellites, an ideal external environment is provided for mobile phones to directly connect to satellites and perform instantaneous Doppler positioning. Starting from practical engineering applications, a Doppler positioning processing method based on low earth orbit satellite signals of opportunity is proposed. The mathematical model of Doppler positioning with low earth orbit satellite signals of opportunity is derived and analyzed, and the algorithm flow of the Doppler positioning with low earth orbit satellite signals of opportunity is given. Simulation verification is performed based on Two Line Elements(TLE) data of Iridium Next, Starlink, OneWeb, Orbcomm, and Globalstar satellites. The results show that under the theoretically error free condition, the variance of Doppler positioning accuracy is less than 1 m; when the ground terminal time accuracy is 1.0 ms and the speed measurement accuracy is 0.2 Hz, the Doppler positioning accuracy variance is meter-scale.