WKB近似下的Fourier衍射成象方法

对于介质目标微波衍射成象，本文引入了ＷＫＢ近似来模拟目标内部总场。基于这种近似，我们导出了Ｆｏｕｒｉｅｒ衍射公式，并采用了广义滤波逆传播方法由目标空间谱实现目标特性的重建。计算机模拟结果表明采用ＷＫＢ近似重建目标特性较Ｂｏｒｎ近似有明显改善。

Fourier Diffraction Imaging Under WKB Approximation

For microwave diffraction imaging, we use the WKB approximation to estimate the total field in the dielectric object. Compared to the Born approximation, the amplitude and phase of total field in the object are modified. The Fourier Diffraction Theorem that is quite similar to the one proposed by Wolf(1969) is then derived. By using the extended filtered backpropagation algorithm the object can be reconstructed from the spatial spectrum. The computer simulations show that the quality of image reconstructed by proposed scheme is superior to the one produced by Born approximation.