基于多台北斗接收机的测姿精度对目标定位精度影响分析

飞机姿态测量是无人机系统目标定位的重要环节。该文拟采用多台北斗天线测姿，分析了北斗接收天线测姿精度对机载光电平台目标定位精度的影响。为此，本文建立机载光电平台目标定位系统模型，用蒙特卡洛法分析目标定位误差,并对飞机姿态测量误差在0.05°~1°范围内以及飞行高度在1 000~8 000 m时的垂直下视和斜视目标定位误差进行比较。实验结果表明，在姿态测量误差及飞行高度范围内，垂直下视目标定位高程误差在20 m左右，平面定位误差为23~65 m；斜视定位（-60°斜视，俯仰轴以水平向前为0°）大地高误差为20~30 m,平面定位误差为24~71 m。同时分析了天线摆放及基线长度对测姿精度的影响。目标定位误差主要与飞机姿态角测量误差、北斗系统误差、光电平台方位角和高低角测量误差有关，还与目标与飞机之间的斜距有关。飞行高度越大，光电平台高低角越小，斜距越大，则目标定位误差越大。基线越长，测姿精度越高，当基线垂直时，横滚角误差最小。

Impact analysis of attitude determination accuracy to target localization accuracy on Multi-BD receivers

Aircraft attitude measurement is an important phase in the target location of UAV (Unmanned Aerial Vehicle, UAV) system. This paper intends to achieve attitude information by using multi-BDS (BeiDou navigation positioning system, BDS) receiver antenna. Furthermore, the influence of the attitude measurement accuracy on the positioning precision of airborne optoelectronics platform is analyzed. To solve these problems, a target location system model of airborne optoelectronics platform is established. After analyzing and calculating the orientation error with Mont Carlo method, the errors are compared among the cases including the airborne attitude measuring error within 0.05°~1°, the positioning precision of vertical view and strabismus in flying height of 1 000~8 000 meters.The experimental results show that elevation error of vertical view is about 20m, and planar location error is 23~65 m. Geodetic height error of strabismus positioning (-60° oblique) is about 20~30 m,and planar location error is 24~71 m. In addition, the effects of the antenna orientation and length of baseline on the positioning precision are analyzed. Some conclusions can be drawn by simulation. Target location errors relate to the attitude angle error of the aircraft, the error of BDS, azimuth angle error of optoelectronic platform, high and low angle measurement error, and the distance between the target and the aircraft.Moreover,it can be concluded that the high and low angle of optoelectronic platform is smaller when the flying height is higher. The positioning error is larger when slant distance is bigger. The attitude measurement accuracy is greater when the baseline is longer. The error of rolling angle is the minimum when the baseline is vertical.