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Unified Initial Preprocessing for Phaseless Characterization of Quiet Zone in Millimeter-Wave Compact Antenna Test Range

This letter proposes a unified initial preprocessing technique to address phaseless characterization of a compact antenna test range (CATR) system within millimeter-wave range. With the aid of phase retrieval algorithm, the missing phase information of quiet zone (QZ) can be reconstructed by only two amplitude-only measurements. Here, the initial complex information consists of two parts: back propagation of measurements in QZ as initial amplitude and Zernike-Fourier expansion as initial phase. To further validate the superiority and robustness of the proposed approach, we conduct extensive simulations over the state-of-the-art phase retrieval algorithms under different operating frequencies and compare it to different initial preprocessing methods. In addition to be readily available in practical applications, the proposed technique is also verified under experimental conditions. In a nutshell, this letter paves the way toward the applications of phaseless characterization in CATR system.