Planar Near-Field Phaseless Measurements Using Multi-Probe Arrays

Near-field measurements of antennas with integrated sources is a current challenge. The lack of a reference channel forces to apply phaseless techniques with high levels of oversampling and poor recovery guarantees. On this line, multi-probe systems bring numerous advantage. Not only they provide measurement time savings, but also enable the measurement of the relative phases between probes. This paper proposes a fast planar phaseless technique based on an optimized grid designed to minimize measurement time. The optimized grid is scanned by a probe array which extracts the magnitude and relative phase between the neighboring samples. This partial phase information is fed to a state-of-the-art phase retrieval technique which reconstructs the complete phase signal and the antenna far-field. To demonstrate the capabilities of the proposed technique, a simulation example with the VAST12 antenna is presented, where the total number of samples is reduced by a factor of 100 using a <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4× 4</tex> probe array.