Simulation Study Of Several Characteristics Of LEO-LEO Occultation Events

In recent years,the GNSS-LEO radio occultation detection technology developed rapidly with the advantage of effectively detecting the various parameters of the neutral atmosphere and the ionosphere information,as one of the world's most advanced space detection technology in the 21 st century.However,water vapor fuzzy phenomenon exists in GNSS-LEO occultation inversion results when earth's lower atmosphere water vapor is inversed.In order to solve this problem,LEO-LEO occultation detection technology arises at the historic moment.With the advantage of all-weather,large detection range,high accuracy,and high vertical resolution,many domestic and overseas institutions and scholars attach importance to LEO-LEO occultation detection technology.In order to making further development of the LEO-LEO occultation detection technology in our country.Several features of LEO-LEO occultation events has been simulated and analyzed in this paper.Through the setting the orbit parameters of the satellite orbit altitude,inclination,Right Ascension of Ascending Node(RAAN)and Argument of Perigee(AP),we analyzed the impacts of satellite orbit parameters on the occultation events feature such as quantity,global distribution,time duration,drift of tangent point of occultation events and relatively angular velocity between satellites.According to the simulation studies about occultation events at home and abroad and the simulation of LEO-LEO occultation events in this thesis,the valuable reference was provided about solving the problem of the energy consumption of satellite,occultation data storage,the effective capture of occultation signal and so on.And the recommendation was given for design of LEO-LEO occultation orbit and satellite transmitter and receiver.First of all,according to the demand of the detection area,the satellite orbit inclination should be determined,and be supplementary angle each other as close as possible.For the global detection constellation,satellite orbit inclinations should both be close to 90 °.For the middle latitude detection constellation,the orbit inclination of transmitting satellite or receiving satellite should be distributed in 45 ° ~ 60 °.For the low latitude detection constellation,the orbit inclination of transmitting satellite or receiving satellite should be around 30°.Then the Right Ascension of Ascending Node(RAAN)should be determined.To satisfy the needs that the occultation quantity is more,drift of tangent point is smaller and time duration is shorter,the difference between the RAAN of two LEO orbits should be within the scope of the 150 ° ~ 210 °.Thirdly the satellite orbit altitude should be determined.To satisfy the needs that the occultation quantity is more,drift of tangent point is smaller and time duration is shorter,two orbit altitudes should be close to each other.Finally when LEO-LEO occultation antenna is designed,maximum rotation angular velocity in horizontal and vertical direction should be able to achieve 0.14 ° / s and 0.078 ° / s.An example of LEO-LEO occultation constellation was analyzed.Impacts of satellite orbit parameters on quantity,global distribution,time duration,drift of tangent point of occultation events and relatively angular velocity between satellites were analyzed through the simulation data.The result is consistent with the future of the LEO-LEO occultation events.