低轨卫星的北斗反射信号海洋覆盖分析

Ocean Cover Analysis of the Beidou Reflection Signal of Low-orbit Satellite

北斗系统作为我国自行研制的导航系统,具有独特的混合星座特性,其反射事件在海洋上的空间分布和覆盖性能的研究成果较少。针对上述问题,模拟了北斗三号(Beidou System 3,BDS3)以及全球定位系统(Global Positioning System,GPS)空间星座,模拟不同性能参数的低轨接收卫星,在此仿真系统的基础上,计算反射事件在各仿真场景下的海洋覆盖率以及同时发生反射事件的卫星数量。结果表明:BDS3与GPS相比具有更大的反射事件海洋覆盖率,覆盖性能更优;仿真周期7天与1天相比,前者卫星产生的反射事件海洋覆盖率约为后者5倍;低轨道卫星(Low Earth Orbit,LEO)轨道高度越高,天线波束角度越大,反射事件海洋覆盖率越大;3颗LEO卫星下同时发生反射事件卫星数的平均值约为单颗LEO卫星的3倍。可通过设计多星组网来提高反射事件海洋覆盖率。研究结果对星载反射技术海洋遥感应用方面有一定的参考价值。

The Beidou system,as a self-developed navigation system in my country,has unique hybrid constellation characteristics,and there are few research results on the spatial distribution and coverage performance of reflection events on the ocean. In response to the above problems,Beidou System 3( BDS3) and Global Positioning System( GPS) space constellations were simulated,and low-orbit receiving satellites with different performance parameters were simulated. Based on this simulation system,the reflection was calculated The ocean coverage of the event in each simulation scenario and the number of satellites that have reflected events simultaneously. The results show that: BDS3 has a larger reflection event ocean coverage and better coverage performance than GPS;the simulation event period of 7 days is compared with 1 day,and the former satellite’s reflection event ocean coverage is about 5 times that of the latter;low The higher the orbital altitude( Low Earth Orbit,LEO) orbit,the greater the angle of the antenna beam,the greater the ocean coverage of reflection events;the average number of satellites that simultaneously reflect reflection events under 3 LEO satellites is about 3 for a single LEO satellite Times. Multi-star networking can be designed to improve the ocean coverage of reflection events. The research results have certain reference value for the application of spaceborne reflection technology in marine remote sensing.