GNSS反射信号在沙丘形状探测中的应用

Application of GNSS Reflected Signal in Sand Dune Shape Detection

为了拓展全球导航卫星系统(Global Navigation Satellite System,GNSS)的应用范围,充分利用多径效应,提出GNSS反射信号进行沙丘形状探测的方法。该方法利用地基探测法,在同一地点架设直射与反射信号的接收天线,实现对地表反射卫星信号的接收。利用解算软件对直射信号和反射信号进行判别和捕获,结合GNSS-R微观几何关系求解出直射信号和反射信号的路径差,锁定反射面的位置信息。变换观测地点,获得沙表多点三维信息,拟合形成沙丘形状。实验选用一片背风沙坡对GNSS卫星反射信号进行实测,所得曲面与利用全站仪测量数据所获曲面对比,结果表明2种方法所获曲面相似,证明了GNSS反射信号测量沙丘形状的正确性以及用于观测沙丘移动变化的可行性,为裸土地形探测提供了新的手段。

In order to expand the application scope of the Global Navigation Satellite System(GNSS)and make full use of the multipath effect,a method for detecting the shape of sand dunes using GNSS reflected signals is proposed.This method uses ground-based detection to set up a receiving antenna for direct and reflected signals at the same place,so as to realize the reception of satellite signals reflected by the ground surface.Solution software is used to distinguish and capture the direct and reflected signals,and the path difference between the direct and reflected signals is solved by considering the GNSS-R micro-geometric relationship,and the position information of the reflecting surface is locked.Change the observation location to obtain multi-point three-dimensional information of the sand surface and fit the shape of the sand dune.In the experiment,a leeward sand slope is used to measure the reflected signal of GNSS satellite.The resultant curved surface is compared with the curved surface obtained by using the total station for data collection.The results show that the curved surfaces obtained by the two methods are similar,which proves the correctness of using the GNSS reflected signal to measure the shape of sand dune as well as the feasibility of using it to observe the movement and change of sand dunes.It provides a new method for the detection of bare land terrain.