Tracking system for multiple beam antenna

Claim 1

A tracking system comprising: comparator means having first and second hybrid couplers and first and second phase shifters, the phase shift of said first phase shifter occurring in increments which are of equal magnitude to and of opposite sign to increments in the phase shift of said second phase shifter, said first phase shifter being connected between one output port of said first coupler and one input port of said second coupler, said second phase shifter being connected between a second output port of said first coupler and a second input port of said second coupler, said first coupler having a plurality of input ports for coupling to an antenna system having a multiple beam radiation pattern; means coupled to said second hybrid coupler for sensing a direction relative to said radiation pattern of radiant energy incident upon said antenna, said sensing means providing signals to said first phase shifter and said second phase shifter for controlling the magnitudes of said shifts whereby a null between two beams of said radiation is positioned along the direction of said incident radiant energy; a switch for sequentially coupling said first hybrid coupler to pairs of beam output signals of said antenna system; and wherein said sensing means further provides a first signal indicating that the magnitude of one of said shifts is greater than a predetermined amount, and a second signal indicating a sign of said first signal, said sensing means further comprising a counter responsive to said second signal for counting occurrences of said first signal, a count of said counter being coupled to said switch for operating said switch to a different position thereof corresponding to said count.