多点定位系统应用于广域目标定位时,由于精度几何弱化因子的影响,采用三维定位算法直接进行目标定位的精度比较差,甚至有发散的可能。由于用于定位的民航机载二次应答机所发送的部分应答信号中含有目标的气压高度信息,利用该气压高度信息,对三维定位算法进行修正,降低定位方程的维度,保证算法的收敛性,提高定位精度。该算法应用于实际系统的测试结果证明,采用该算法的目标定位精度有了很大提高。
For the impact of Geometric Dilution of Precision(GDOP) on the wide area multilateration systems,the adoption of three-dimension positioning algorithm for direct position of the targets would result in the problem of low accuracy or even divergence.For parts of response signals sent by onboard transponders contain barometric altitude of the target,this information could be employed to adjust the three-dimension positioning algorithm and reduce the dimensions of positioning equations,thus ensuring the convergence of algorithm and increasing the accuracy of positioning.Real-test results show that this method could greatly raise the accuracy of positioning solution.