Primary and Secondary Patterns From Array-Fed Off-Set Reflector Antennas

Abstract

The paper describes how mutual coupling influenees both the primary and secondary radiation patterns of array-fed off-set reflector antennas. The principle cause of adverse crosspolarisation is attributed to coupling between the TE11 and TE21 modes in the array. This then is the main cause of crosspolarisation in an optimised dual reflector. It is shown that coupling to the TE21 mode can be minimised with the correct choice of horn.