A hybrid approach for phaseless imaging of dielectric targets is proposed in this letter. A two-probe measurement strategy with the related phase-retrieval method is adopted in conjunction with an inversion procedure based on an inexact-Newton method to give an efficient and low-cost imaging setup, avoiding the need of multiple acquisition surfaces. A preliminary experimental validation on real input data is presented.

Microstrip reflectarrays are proposed as reference targets in alternative to standard Permanent Scatterers for SAR interferometry applications. A more stable and flat structure is obtained with respect to usually adopted corner reflectors, with a simple design procedure easily giving a backscattered field in a prescribed direction of incidence. Numerical results as well as experimental validations are discussed to assess the validity of the proposed approach. PS, microstrip reflectarrays composed of variable size patches are assumed in this work.