基于MHSS算法的ARAIM完好性和可用性预测

Prediction of ARAIM integrity and availability based on MHSS algorithm

传统的接收机自主完好性监视只能提供非精密进近阶段的完好性监视,无法实现对完好性要求更加严格的飞行阶段的监视,而高级接收机自主完好性监视(Advanced Receiver Autonomous Integrity Monitoring,ARAIM)可以在精密进近阶段为飞机提供满足航向信标性能垂直引导(Localizer Performance with Vertical guidance,LPV)的完好性监视服务。文章基于多假设分组解算法,根据目前的星座环境,结合民航不同飞行阶段的应用需求,对ARAIM算法进行仿真研究。针对水平保护级(Horizontal Protection Level,HPL)和垂直保护级(Vertical Protection Level,VPL)的指标,在不同星座组合环境下,选取南北半球不同经纬度的5个观测机场,分别仿真了HPL和VPL的变化情况,并对全球HPL和VPL平均分布趋势,以及以99%的概率满足LPV-200进近可用性指标时,ARAIM可用性的全球覆盖率进行了仿真预测分析。仿真结果表明,不论是全球定位系统和格洛纳斯双星座还是增加北斗卫星导航系统后的三星座,5个观测机场的HPL和VPL均能满足LPV-200进近对完好性指标的要求;但在全球范围内,双星座条件下,ARAIM并不能完全支持LPV-200进近对完好性监视的要求,而三星座则可大大提高ARAIM的可用性,为民航用户提供满足精密进近的所需导航服务性能。

As the traditional receiver autonomous integrity monitoring（RAIM）merely provides non-precision approach integrity monitoring,a stricter monitoring service won′t be available by RAIM.However,advanced receiver autonomous integrity monitoring（ARAIM）,which supports localizer performance with vertical guidance,can meet the requirements of integrity monitoring within precision approach.Based on multiple hypothesis solution separation（MHSS）algorithm and different constellation situation,the solution process of horizontal protection level（HPL）and vertical protection level（VPL）for ARAIM was expounded.Five observation airports located at different longitudes and latitudes in the north and south hemispheres were selected to simulate the changes of the HPL and VPL under different combination of constellation systems as well as the average distribution trend of the HPL and VPL around the world and global coverage ratio of the ARAIM availability,which met the availability requirements of the LPV-200 approach with 99% probability.The simulation results show that the HPL and VPL of that five observation airports can meet the integrity requirements of the LPV-200 approach for both the GPS GLONASS dual-constellation and the GPS GLONASS BDS tri-constellation,however,ARAIM can not fully support the requirements of integrity monitoring for the LPV-200 approach worldwide under the condition of the GPS GLONASS dual-constellation,whereas the availability and navigation service performances of the ARAIM can be greatly improved when GPS GLONASS BDS triconstellation is used.