Phase retrieval radio holography for large reflector antennas

This paper describes and implements an approach to the problem of determining the antenna aperture field distribution from only amplitude measurements of far-field pattern. We apply the quadratic approach for recovering the complex aperture field function from measurements of the pattern at different feed locations. The phase-retrieval procedure consists of minimizing a nonquadratic functional and a reliable iterative algorithm converging on the solution, regardless of the starting point, is thus obtained. This approach to phase-retrieval problem has been compared with well-known Misell algorithm. Also, the effectiveness of both algorithms has been verified by results of conventional with-phase holography with using the experimental data obtained on 70-meter mirror antenna.