近程毫米波全息成像算法

摘要

For the declining of the imaging resolution caused by phase interference in the short-range millimeter wave imaging process, the holographic imaging algorithm is introduced to study the mmw imaging of short-range targets. Electromagnetic wave is transformed from space domain to wave number domain in the algorithm. For spherical wave front of the electromagnetic waves, the signal phase of the array element is adjusted effectively in space wave number spectrum and is added. It effectively suppresses interference effects and improves the imaging resolution. The target size is restricted in this algorithm. On this basis, the algorithm of wave number domain extrapolation is proposed to large size target imaging. The measuring surface and source surface are extrapolated and intercepted reasonably. Winding effect and Gibbs effect are inhibited and image quality is improved.%针对近程目标毫米波成像过程中由于相位干涉而导致成像分辨率下降的问题,把全息成像算法引入到近程毫米波成像.该算法通过电磁波从空间域到波数域的转换,针对电磁波的波前球面弯曲,在空间波数谱上有效调整各阵元信号的相位,使之同相相加,从而有效抑制干涉效应,提高成像分辨率.以上算法对目标尺寸有一定的限制,对于大尺寸目标的成像,提出了波数域外推算法,通过对测量面和源面的合理外推及截取,有效抑制了卷绕效应和Gibbs效应,同样提高成像质量.