Method and device for detecting moving objects by radio means

Claim 1

A DEVICE FOR DETECTING NEARBY MOVING OBJECTS COMPRISING, IN COMBINATION, A MULTIPLICITY OF TRANSMISSION STATIONS, EACH ONE OF WHICH COMPRISES A TRANSMITTER COMPRISING A VHF SELF-OSCILLATOR GENERATING A CARRIER-WAVE OF VERY HIGH FREQUENCY, AN EMITTING ANTENNA COUPLED TO SAID TRANSMITTER, AN AUXILIARY IF OSCILLATOR GENERATING AN INTERMEDIATE-FREQUENCY WAVE, AND MEANS FOR AMPLITUDE-MODULATING SAID CARRIER-WAVE BY SAID INTERMEDIATE FREQUENCY WAVE WHICH CONSTITUTES A SUB-CARRIER WAVE; AND A MULTIPLICITY OF RECEPTION STATIONS, EACH ONE OF WHICH COMPRISES A RECEIVING ANTENNA, A RECEIVER COUPLED TO SAID RECEIVING ANTENNA AND COMPRISING A FIRST WIDE-BAND DETECTOR WHICH FURNISHES THE VARIOUS SUB-CARRIERS EMITTED BY ALL SAID TRANSMISSION STATIONS WHICH ARE AMPLITUDE-MODULATED BY THE DOPPLER EFFECTS RESULTING FROM THE BEATS BETWEEN THE WHOLE OF THE WAVES EMITTED BY ALL SAID TRANSMISSION STATIONS AND THE WHOLE OF THE WAVES REFLECTED FROM A MOVING OBJECT TO BE DETECTED, A MEDIUM-BAND AMPLIFIER WHICH IS TUNED TO HE BAND OF THE FREQUENCIES OF ALL THE EMITTED SUB-CARRIERS AND WHICH RECEIVES ITS SIGNALS FROM SAID WIDE-BAND DETECTOR, A SECOND DETECTOR SUPPLIED BY SAID AMPLIFIER AND FURNISHING ALL THE DOPPLER SIGNALS DUE TO THE BEATS OF ALL THE CARRIER WAVES EMITTED WITH ALL THE ECHO WAVES, A VERY-LOW-PASS-BAND FILTER HAVING A TIMECONSTANT, RECEIVING THE DOPPLER SIGNALS OF SAID SECOND DETECTOR AND FURNISHING ONLY THE DOPPLER BEAT SIGNALS BETWEEN ALL THE CARRIER WAVE EMITTED AND THEIR OWN ECHO WAVES FROM THE MOVING OBJECT, AND A WARNING DEVICE SUPPLIED FROM SAID FILTER, THE FREQUENCIES OF AT LEAST ONE OF THE TWO GROUPS FORMED BY THE CARRIER WAVES AND THE SUBCARRIER WAVES EMITTED BY THE TRANSMITTERS BEING DIFFERENT FROM ONE TRANSMITTER TO ANOTHER AND CHOSEN FROM A SMALL NUMBER OF NEIGHBOURING FREQUENCIES.

Claim 2

A DEVICE FOR DETECTING NEARBY MOVING OBJECTS COMPRISING, IN COMBINATION, A MULTIPLICITY OF TRANSMISSION STATIONS, EACH ONE OF WHICH COMPRISES A TRANSMITTER COMPRISING A VHF SELF-OSCILLATOR GENERATING A CARRIER-WAVE OF VERY HIGH FREQUENCY, AN EMITTING ANTENNA COUPLED TO SAID TRANSMITTER, AN AUXILIARY IF OSCILLATOR GENERATING AN INTERMEDIATE-FREQUENCY WAVE, AND MEANS FOR AMPLITUDE-MODULATING SAID CARRIER-WAVE BY SAID INTERMEDIATE FREQUENCY WAVE WHICH CONSTITUTES A SUB-CARRIER WAVE; AND A MULTIPLICITY OF RECEPTION STATIONS, EACH ONE OF WHICH COMPRISES A RECEIVING ANTENNA, A RECEIVER COUPLED TO SAID RECEIVING ANTENNA AND COMPRISING A FIRST WIDE-BAND DETECTOR WHICH FURNISHES THE VARIOUS SUB-CARRIERS EMITTED BY ALL SAID TRANSMISSION STATIONS WHICH ARE AMPLITUDE-MODULATED BY THE DOPPLER EFFECTS RESULTING FROM THE BEATS BETWEEN THE WHOLE OF THE WAVES EMITTED BY ALL SAID TRANSMISSION STATIONS AND THE WHOLE OF THE WAVES REFLECTED FROM A MOVING OBJECT TO BE DETECTED, A MEDIUM-BAND AMPLIFIER WHICH IS TUNED TO HE BAND OF THE FREQUENCIES OF ALL THE EMITTED SUB-CARRIERS AND WHICH RECEIVES ITS SIGNALS FROM SAID WIDE-BAND DETECTOR, A SECOND DETECTOR SUPPLIED BY SAID AMPLIFIER AND FURNISHING ALL THE DOPPLER SIGNALS DUE TO THE BEATS OF ALL THE CARRIER WAVES EMITTED WITH ALL THE ECHO WAVES, A VERY-LOW-PASS-BAND FILTER HAVING A TIMECONSTANT, RECEIVING THE DOPPLER SIGNALS OF SAID SECOND DETECTOR AND FURNISHING ONLY THE DOPPLER BEAT SIGNALS BETWEEN ALL THE CARRIER WAVE EMITTED AND THEIR OWN ECHO WAVES FROM THE MOVING OBJECT, AND A WARNING DEVICE SUPPLIED FROM SAID FILTER, THE FREQUENCIES OF AT LEAST ONE OF THE TWO GROUPS FORMED BY THE CARRIER WAVES AND THE SUBCARRIER WAVES EMITTED BY THE TRANSMITTERS BEING DIFFERENT FROM ONE TRANSMITTER TO ANOTHER AND CHOSEN FROM A SMALL NUMBER OF NEIGHBOURING FREQUENCIES.