在地面固定单站对机动目标的无源轨迹预测中，地面固定单站仅提供目标方位角和高低角信息，而没有提供目标距离信息.因此，目标飞行轨迹的预测只能依靠已有的角度信息进行.在无测距信息的情况下，根据匀加速运动和等高飞行2个弱条件假设，提出了仅利用测角系统测得的空中机动目标的高低角和方位角进行目标飞行轨迹预测的算法，并对算法进行了仿真测试.仿真试验结果表明该预测算法角度预测误差在毫弧度以下.

In the passive estimation of mobile target track, the stationary ground platform only provides angular information but no distance information. So, the target flying track must be estimated solely with the existing angular information. A new algorithm, based on uniform acceleration and constant altitude flying mode hypothesis, is presented to estimate the mobile target track according to the measured angular information. A simulation model was built to test the performance of the algorithm. The experimental results show that the estimation algorithm can reduce the angular error to milli-radian or less.