雷达散射计的近场绝对校准技术

Near Field Calibration Techniques for Radar Scatterometer

在推导散射计绝对校准公式的基础上，分析了远区条件对于雷达散射计绝对校准的意义，通过引入有效雷达散射截面的概念，将入射波前球面弯曲和波束限制引起照射不均匀以及接收天线增益的变化等效为目标雷达散射截面的变化，通过修正使近、远场的绝对校准公式得以统一，给出相应的绝对校准方法。实际的绝对校准结果证明了方法的有效性。文中还给出了关于雷达校准器选择和瞄准精度要求的初步讨论。

In this paper,procedure of the absolute calibration for ground based scatterometer is presented.Effects of the far field criterion for the calibration is analyzed.The concept of effective radar cross section(ERCS)is introduced to unify the calibration formula for near field region and far field region measurement.A practical calibration method is proposed.Some calibration results show the validity of the given method.