Reliable Linearized Phase Retrieval for Near-Field Antenna Measurements with Truncated Measurement Surfaces

TL;DR

This paper introduces a linear phase retrieval method for near-field antenna measurements that overcomes sampling, computational, and reliability issues of existing nonlinear approaches, especially for open measurement surfaces.

Contribution

A novel partially coherent multi-probe measurement technique with a linear reconstruction method that improves reliability and accuracy in near-field far-field transformations.

Findings

Effective phase retrieval with open measurement surfaces

Enhanced reconstruction accuracy using multi-probe arrangements

Mitigation of sampling and computational challenges

Abstract

Most methods tackling the phase retrieval problem of magnitude-only antenna measurements suffer from unrealistic sampling requirements, from unfeasible computational complexities, and, most severely, from the lacking reliability of nonlinear and nonconvex formulations. As an alternative, we propose a partially coherent (PC) multi-probe measurement technique and an associated linear reconstruction method which mitigate all these issues. Hence, reliable and accurate phase retrieval can be achieved in near-field far-field transformations (NFFFTs). In particular, we resolve the issues related to open measurement surfaces (as they may emerge in drone-based measurement setups) and we highlight the importance of considering the measurement setup and the phaseless NFFFT simultaneously. Specifically, the influence of special multi-probe arrangements on the reconstruction quality of PC solvers is shown.