Omnidirectional satellite antenna supplying rejection in direction needed

Abstract

The problem of electromagnetic compatibility is one of importance in the VHF-SHF band LEO system design. One of the approaches to resolve this problem is employment of antenna adaptive control methods. But in the case of a simple omnidirectional antenna these methods are useless, as they are based on multielement antennas. The proposed approach to resolve this problem is based on choosing the geometry of the antenna to form a null level of directivity according to the known supply current distribution. An omnidirectional antenna design for satellite terminal use is discussed. It consists of orthogonal crossed dipoles (each in x, y, z axis) possessing a common center. That system of three dipoles is able to form a null level of directivity according to their size ratio and power supply.