Digital Holographic Reconstruction and Filtering Method for Antenna Planar Near-Field Phase-Less Measurement

This letter presents a novel and highly accurate method for antenna near-field (NF) phase-less measurement. The reconstruction process is transplanted from the classical optical hologram approach. The hologram intensity distribution is recorded only in one NF scanning plane. The illumination wave, regenerated from the known reference antenna, is applied to reconstruct the complex field of antenna under test (AUT) by a numerical multiplication. Moreover, when the reconstructed hologram is back-projected to aperture plane from the measurement plane, the desired complex field of AUT is distinguished in the aperture plane and gated by a low-pass filter efficiently. Both simulations and experiments demonstrate the feasibility and accuracy of the proposed method.