Reconfigurable reflector antenna producing pattern nulls

The paper reports how a reconfigurable mesh reflector antenna can be used to generate nulls in its radiation pattern while closely maintaining the original pattern in regions away from the null. The theory is developed and theoretical results are presented for a typical antenna of a size suitable for spacecraft applications. Experimental results, which are in close accord with theory, are given for an offset mesh reflector which is scaled to approximately 30 wavelengths in diameter and is fed by a corrugated horn. It is shown that deep nulls can be formed both within the mainbeam and within the side-lobe region. Applications of the offline mode of operation lie where there is a priori knowledge of the location of the interfering source, which could be the case in civil scenarios, including those of some deep-space missions requiring communication with an Earth-based transmitter