Doppler radar detection system

Claim 1

A DOPPLER RADAR CIRCUIT FOR DETERMINING DOPPLER FREQUENCY COMPRISING A SOURCE OF A RADAR SIGNAL INCLUDING AN ECHO SIGNAL OF VARYING DOPPLER FREQUENCY AND INCLUDING AT INDEPENDENTLY VARYING FREQUENCIES, A CLUTTER SIGNAL AND A NOISE SIGNAL WITH SAID ECHO SIGNAL HAVING A SUBSTANTIALLY NARROW SPECTRUM AND SAID CLUTTER SIGNAL AND NOISE SIGNAL HAVING A SUBSTANTIALLY WIDE SPECTRUM, A PLURALITY OF DOPPLER FILTERS COUPLED TO SAID SOURCE EACH HAVING A BANDWITH FOR PASSING SAID ECHO SIGNAL AND SUBSTANTIALLY NARROW WITH RESPECT TO SAID CLUTTER SIGNAL AND SAID NOISE SIGNAL, THE BANDWITH OF EACH OF SAID FILTERS CENTERED AT A DIFFERENT FREQUENCY FOR PASSING A PORTION OF SAID INTERMEDIATE FREQUENCY SIGNAL, SEPARATE RECTIFIER MEANS COUPLED TO EACH OF SAID FILTERS FOR DEVELOPING A DIRECT CURRENT SIGNAL IN RESPONSE TO A PORTION OF SAID INTERMEDIATE FREQUENCY, SEPARATE THRESHOLD DETECTOR MEANS COUPLED TO EACH OF SAID RECTIFIER MEANS FOR PREVENTING A DIRECT CURRENT SIGNAL DEVELOPED FROM SAID NOISE SIGNAL FROM PASSING THERETHROUGH TO AN OUTPUT TERMINAL AND INCLUDING GATING MEANS CONTROLLING THE PASSING TO SAID OUTPUT TERMINAL OF SAID DIRECT CURRENT SIGNALS DEVELOPED FROM SAID ECHO AND CLUTTER SIGNALS, SEPARATE SUMMING MEANS EACH COUPLED TO A PREDETERMINED PLURALITY OF DIFFERENT ONES OF SAID RECTIFIER MEANS FOR DEVELOPING A COMBINED SIGNAL WHEN SAID DIRECT CURRENT SIGNALS DEVELOPED FROM SAID ECHO SIGNAL OR FROM SAID CLUTTER SIGNALS ARE RECEIVED FROM EACH OF SAID RESPECTIVE PLURALITY OF RECTIFIER MEANS, AND SEPARATE CLUTTER THRESHOLD DETECTING MEANS COUPLED TO EACH OF SAID SUMMING MEANS FOR RESPONDING TO SAID RESPECTIVE COMBINED SIGNAL TO CONTROL SAID GATING MEANS OF SAID RESPECTIVE PLURALITY OF THRESHOLD DETECTING MEANS SO AS TO PREVENT SAID DIRECT CURRENT SIGNALS DEVELOPED FROM SAID ECHO AND CLUTTER SIGNALS FROM PASSING TO SAID OUTPUT TERMINAL.