A data processing system for a phased array antenna consisting of an array of transmit/receive elements which result in a significant reduction in the data processing requirements for the received signals. In operation, the RF transmitted and received beams are formed and steered in a conventional manner with a phase shifter and amplitude weighting for each element. However, a simplifying approximation is made in the signal processing of the received signals for interference suppression, which results in minimal degradation of the system performance. In such a system, interference suppression is obtained by generating nulls in the receive antenna pattern in the direction of the interference. The nulls are produced by adjusting the phase and amplitude (weight) of the received signal from each array element just enough to null the interference with minimal impact on the rest of the antenna pattern. Pursuant to the present invention, the signal processing requirements are significantly reduced by summing the outputs of adjacent array elements to produce a lesser number of summed signals, less than the number of elements in the array. Each summed signal is then directed to a weighted amplifier controlled to weigh the contribution of the particular summed signal to a composite output signal formed by a composite summing circuit, which sums the weighted output signals of all of the weighted amplifiers.

In a point to point microwave communication service including a microwave antenna system at each point directed at the other point, the radiation pattern of the antenna system at at least one point has a substantial null in the direction of an antenna of another microwave communication service to avoid an exchange of signals with the other service, the antenna system provided at said one point includes two antenna elements having substantially equal directional radiation patterns, so oriented and spaced apart a distance that is at least several wave length of the operating frequency of the elements so that the radiation patterns of the elements overlap producing a net radiation pattern that results from interference of the patterns and the net pattern has a substantial lobe in the direction of the other point of said service and a substantial null in the direction of an antenna of the other microwave communication service.