近程目标太赫兹全息成像算法及仿真

Terahertz holographic imaging algorithm and simulation for short-distance target

摘要:

对比传统的基于球面波分解的近程目标太赫兹全息成像算法，以驻定相位法为理论基础对成像算法进行推导，得到了相同的成像补偿公式。采取图像熵的判决准则分析阵元误差对成像结果的影响，为成像系统阵元位置精确度的设计提供理论依据。针对三维目标距离过近出现非补偿距离平面成像结果散焦的现象，对传统成像算法的缺陷进行分析，提出了基于循环补偿与投影合成相结合的近程目标太赫兹三维全息成像方法。220 GHz条件下的Matlab仿真结果验证了所提方法的有效性，实现了三维目标的聚焦成像。

Abstract:

Compared to traditional terahertz holographic imaging algorithm for short-distance targets based on spherical wave decomposition, the same imaging compensation formula is obtained based on the theory of stationary phase method. By analyzing the effect of array elements error on imaging results using the criterion of image entropy, it provides the theory basis to the design of the array elements position precision of imaging system. Aiming at the defocusing and fuzzy in 3-D targets imaging results at non-compensation distance which is too close, the defects of traditional imaging algorithm are analyzed, and terahertz 3-D holographic imaging method is proposed for short-distance target based on the combination of loop compensation and projection synthesis. The Matlab simulation results at 220 GHz show the effectiveness of the proposed method, which realizes the focused imaging of three-dimensional targets.