基于加权最小二乘算法的DME/DME RNAV精度分析

DME是一种通过询问应答的方式为飞行员提供飞机到地面站距离指示的距离测量设备,用于飞机整个航行阶段.而DME/DMERNAV是一种至少利用两台DME共同工作实现在区域导航航线上授权使用的导航方式.为了准确判别DME/DME的运行是否满足我国区域导航航线授权运行规范,优化选择地面DME台站,通过建立水平定位精度模型和运行精度模型,采用加权最小二乘算法分别对DME/DME的水平定位精度和RNAV三种常用运行方式的定位精度进行了仿真分析,通过仿真给出了影响DME/DMERNAV运行精度的两个重要因素,DME测距精度和两DME台站内夹角,为RNAV飞行管理系统选取满足RNAV运行规范DME和台站切换提供了可靠的判决依据.

DME/DME RNAV accuracy analysis based on the weighted least squared algorithm

Distance measuring equipment (DME) provides pilots with distance information between the aircraft and the ground station, and is used in all phases of flight. DME/DME RNAV is authorized for navigation on China Area Navigation (RNAV) routes, where DME ranging from at least two DME facilities are used to determine the aircraft's horizontal position. In order to precisely determine whether the DME/DME RNAV operation accuracy meets China Area Navigation authorized specification, the weighted least-squares algorithm is given out. Then, the DME/DME horizontal accuracy model and RNAV accuracy model were built. Based on the horizontal accuracy model, the method is applied to analyze the horizontal accuracy of DME/DME, where only two DME rangings are used. And, based on the RNAV accuracy model, the position accuracy of three common cases of the DME/DME RNAV operation is computed and simulated. The simulated results show that the DME/DME RNAV operation accuracy depends on the accuracy of each DME ranging signals as well as the inclusion angle between the two DMEs used in determining the position. So, these results can be served for DME/DME RNAV flight management system in DME stations selection and station switch.