基于时频差测量的双机无源定位的线性解析方法

Linear Analytic Method for Double-plane Passive Location Based on TDOA and FDOA

先将多普勒频移方程中的三角函数同时用直角坐标系和极坐标系的变量表示,然后通过联解对应于双机位置处的两个多普勒频移方程,消去多普勒频移方程中所包含的直角坐标系分量,可得到一个仅包含未知径向距离的方程。在此基础上,利用基于极坐标系的时差方程,即可直接解得目标的距离。更进一步,利用多普勒频移与时差之间的关系可消去方程中所包含的多普勒频移。由此得到仅基于时差和频差测量的无模糊测距解析解。

If the circular function in Doppler shift equation can be expressed concurrently as the variable in rectangular coordinate system and polar coordinate system,an equation only containing unknown radial distance can be obtained by expunging the variable in rectangular coordinate system making use of simultaneous inference for two Doppler shift equations corresponding to the location of two airplanes. On this basis,the object distance can be derived by using time difference equation based on polar coordinate system. What＇s more,by expunging the Doppler shift in equation making use of the relationship between Doppler shift and time difference,we can obtain an unambiguous analytic solution of passive ranging which is only associated with time difference and frequency difference.