Abstract: An antenna array for combining in space microwave energy from a number of cillators, such as IMPATT diodes, which are controllable by injection locking. The array has elements individually driven by the oscillators, but an injection locking signal is provided in the usual manner only to the oscillator of a central element. The other oscillator are injection locked through mutual coupling between the central element and the other elements so that coherent radiation is output by the array. The radiation may be steered by phase shifters between the elements and their oscillators.

Abstract: A plurality of strip-line elements are used as an antenna array. The direvity of the array is controlled by controlling the terminating reactance of the closely-coupled stripline elements.

Abstract: An antenna system for adaptive steering in azimuth and elevation. The sys utilizes a cross-shaped, planar, microstrip array with a central receiving element and with arms of parasitic elements having individual phase shifters which are simultaneously adjusted. In steering a null, the phase shifters are initially adjusted in a "random search" mode and are then adjusted in a "guided random search" mode.