ELECTRONIC TRACKING SYSTEM FOR MICROWAVE ANTENNAS

摘要

A directive antenna which includes electrical means for modifying the electrical properties of the antenna, to provide the antenna with a plurality of discrete receptional states, the antenna comprising a waveguide adapted to support a fundamental propagation mode associated with boresight reception and a plurality of discrete higher order propagation modes associated with the receptional states, wherein the waveguide is coupled to a plurality of propagation mode conversion cavities each of which is switchable between a disabled condition in which it has little or no effect on the mode of propagation of the waveguide and an enabled condition in which it converts a higher order propagation mode to the fundamental propagation mode, so as to displace the direction of optimum reception from the boresight to a predetermined direction.