3D Radiation Pattern Reconstruction of Millimeterwave Wireless Device with Phaseless Nearfield Measurement

This paper explores the application of the Iterative Fourier Transform (IFT) algorithm for reconstructing antenna radiation patterns using phaseless near-field measurements. A detailed comparison between two variants of the IFT algorithm is conducted to evaluate their convergence efficiency and accuracy in phase retrieval. The selected IFT variant was validated through measurements of a 96 GHz horn antenna. We studied key phaseless measurement parameters to ensure proper control over their impact on the algorithm, as well as to optimize and accelerate measurement times according to specific needs. It was demonstrated that the IFT algorithm is robust even when the defined aperture size exceeds the actual antenna size and can also be used to approximate the true antenna size by refining from a larger initial value. After algorithm validation, we applied it to an integrated antenna array within a 60 GHz Wi-Fi module to characterize its radiation in standalone mode, both with and without the enclosure, as well as when connected.