Study on the phase factor of phase retrieval algorithm for surface diagnosis of large reflector antennas.

Surface diagnosis methods based on phase retrieval algorithm have been successfully applied to many large reflector antennas. In the phase retrieval algorithm, surface distortion is retrieved by multiple far field patterns. The different far field patterns are connected to each other by an important element called 'phase factor'. This study investigates the effect of the phase factor on the phase retrieval algorithm. Generally, the phase factor is simple for the phase retrieval algorithm. In this study, a new method based on the active surface system is proposed to produce more flexible and diverse phase factors. Through digital simulations, the effect of different kinds of phase factors on the phase retrieval algorithm is discussed. In addition, the inaccuracy of the phase factor caused by the mechanism error is considered.. [ABSTRACT FROM AUTHOR]