Abstract: Where there is a difference in the angle of arrival between desired incom signals and interfering signals, the reception of the desired signals is maximized by the creation of nulls in the direction of the interfering signals. A high quality receiving (or transmitting) beam is formed by a one-time calculation of the proper phase or amplitude adjustment required to create a null in the direction of each interfering signal. The antennae are then appropriately adjusted to establish the nulls.

Abstract: In an adaptive antenna system, the output of the discriminator of an FM receiver is synchronously rectified, in synchronism with commutation of the input thereof between a pair of antennas, to provide an output signal. When the inputs of the receiver are coupled directly to the antennas, the system may be employed in a homing mode. The output of the rectifier may alternatively be employed to control amplitude and/or phase controls connected between a pair of antennas and the input circuits of the receiver, for the use of the receiver in an adaptive system. For control of amplitude, a quadrature hybrid may be connected between the antennas and the input circuit of the receiver, in order to balance the amplitude of the received signals.