Phaseless antenna characterization by prolate function expansion of the aperture field

To be of actual interest for practical applications, phaseless antenna characterization must be reliable and accurate. This inverse problem suffers from the ill-posedeness, and its solution is very sensitive to the adopted formulation that should be able to incorporate all the available information. An “effective” representation of the unknowns is able to reduce the overall number of parameters to be sought for and therefore to have significant beneficial effects on both accuracy and reliability. This aim is attained by means of a prolate spheroidal wave function expansion of the aperture field, which allows accounting for the finite dimensions of the antenna aperture with the least possible number of parameters. Numerical and experimental results point out the accuracy and reliability of the proposed algorithm, also in comparison with other available methods