Radar system for reducing angle tracking errors

Claim 1

A receiver for a tracking radar system operating in the microwave to millimeter wave region in a noncoherent mode, comprising: antenna means including focusing means for focusing received radiation at a focal plane, an array of detector elements located at the focal plane, the array being divided into four quadrants with at least one detector element in each quadrant; four receiving channels, each coupled via its individual feed means to a corresponding one of said quadrants, each channel including amplitude detection means, and providing an output signal proportional to the amplitude of the received radio frequency energy on its quadrant; wherein said amplitude detection means of each channel includes an amplitude detector which produces a train of pulses, and integrating means to integrate the train of pulses to form said output signal, such that no phase information is extracted from the received signals; and comparison means coupled to the four receiving channels for comparing said output signals from diagonally opposite quadrants to produce error signals for use in driving the antenna means to move the focus of the received radio frequency energy toward the center of the array.