Radar target angle measuring system

Claim 1

A radar system for measuring the angle of a target comprising: radar antenna means for producing at any instant one of a pair of directional radar beams, said beams angularly displaced with respect to each other and overlapping each other within the expected target direction; radio frequency pulse means for generating and transmitting to said radar antenna means a train of radio frequency pulses to form a target acquisition cycle; antenna beam switching means connected between said radar antenna means and said pulse means for switching, over a common time period, a first series of pulses extracted from said train of pulses to one of said radar beams and a second series of pulses extracted from said train of pulses to the other of said radar beams; said first series of pulses being formed from every other pulse in said train of pulses and said second series of pulses being formed from the other of said pulses in said train of pulses; said first series of pulses forming a first code and said second series of pulses forming a second code that differs from said first code; radio frequency signal receiver means connected to said antenna means for receiving signals received by said antenna means during a predetermined time slot corresponding to a given range interval; means for correlating signals received by said radio frequency receiver means with signals corresponding to said first and second codes to form first and second correlation outputs; and means for determining the ratio of energy in said first and second correlation outputs to obtain to target angle.