基于大地经纬度的二维TDOA无源定位

2D-TDOA passive location based on geodetic longitude and latitude

因地球表面并非平面,采用平面坐标的传统TDOA无源定位模型可能存在一定的误差。为了直接利用大地经纬度坐标进行TDOA定位,提出了基于球面两点间距离计算的一系列球面距离计算TDOA定位模型。通过最优化建模,以网格逐点搜索求解法进行模型验证。数值分析结果表明,球面精确计算模型定位误差最小,与纬度无关;球面近似计算模型的定位误差次之,随纬度升高而增加;等距离正圆柱投影模型在低纬度地区定位误差较小,但在中、高纬度地区定位误差大;等角度正圆柱投影模型和等面积正圆柱投影模型的定位误差比较大,在任何纬度时均在26%左右,不可用。

Because of the surface of the earth is not a plane, there may be some errors in the conventional ultra-short wave passive TDOA location method using plane coordinates. In order to use the geodetic longitude and latitude coordinates di- rectly for TDOA location, a series of spherical distance TDOA location models based on spherical two-point distance calcu- lation were proposed. The optimal location models were adopted, and a grid point search method was applied with model validation. The numerical results show that the spherical precise calculation model has the smallest positioning error, which is independent of latitude. Positioning error of the spherical approximation calculation model is worse than the first model, and increases with the increase of latitude. The equidistant orthographic cylindrical projection model has a small positioning error in the low latitudes. However, it has a large positioning error in the middle and high latitudes. The equiangular ortho- graphic cylindrical projection model and the equiareal orthographic cylindrical projection model have a relatively large posi-tioning error, which is around 26% at any latitude and is not applicable.