Exclusive radio communication between stations at selected locations

Claim 1

SELECTIVE RADIO COMMUNICATION APPARATUS COMPRISING MEANS FOR RADIATING AND RECEIVING PULSES OF ELECTROMAGNETIC ENERGY, NORMALLY RESPONSIVE INPUT GATING MEANS COUPLED TO SAID RECEIVING MEANS FOR PASSING RECEIVED PULSES, FIRST DELAYING MEANS COUPLED TO SAID INPUT GATE AND RESPONSIVE TO PULSES PASSED THEREBY FOR PRODUCING RESPECTIVE SIGNALS EACH HAVING A DURATION REPRESENTING A FIRST DELAY PERIOD, MEANS RESPONSIVE TO SAID SIGNALS OF SAID FIRST DELAYING MEANS FOR TRANSMITTING PULSES AT THE CONCLUSION OF EACH OF SAID DELAY PERIODS, MEANS COUPLED TO SAID FIRST DELAYING MEANS FOR INTRODUCING A MODULATING SIGNAL TO SAID DELAYING MEANS, SAID DELAYING MEANS RESPONDING TO SAID MODULATING SIGNAL TO VARY THE DURATION OF SAID FIRST DELAY PERIOD IN ACCORDANCE WITH SAID MODULATING SIGNAL, WHEREBY THE TIME OF OCCURRENCE OF SAID TRANSMITTED PULSES VARIES IN ACCORDANCE WITH SAID MODULATING SIGNAL, A SECOND DELAYING MEANS COUPLED TO SAID FIRST DELAYING MEANS AND OPERABLE AT THE CONCLUSION OF EACH OF SAID FIRST DELAY PERIODS TO PRODUCE A SIGNAL HAVING A DURATION REPRESENTING A SECOND DELAY PERIOD, MEANS FOR COMBINING SAID FIRST AND SECOND DELAYED SIGNALS TO PRODUCE A RESULTANT SIGNAL HAVING A DURATION EQUAL TO THE SUM OF SAID TWO SUCCESSIVE DELAY PERIODS, MEANS COUPLED TO SAID SECOND DELAYING MEANS AND OPERABLE AT THE CONCLUSION OF SAID SECOND DELAYED SIGNAL FOR PRODUCING A SHORT FIXED-TIME SIGNAL HAVING A DURATION GREATER THAN THE DURATION OF A RECEIVED PULSE, MEANS FOR COMBINING SAID RESULTANT SIGNAL AND THE SUCCESSIVELY FOLLOWING FIXED-TIME SIGNAL TO PRODUCE A DIFFERENCE SIGNAL HAVING A DURATION WHICH COMMENCES AT THE CONCLUSION OF SAID FIXED-TIME SIGNAL AND CONCLUDES AT THE TIME OF OCCURRENCE OF THE NEXT SUCCEEDING RESULTANT SIGNAL, MEANS FOR DERIVING A BIASING VOLTAGE HAVING A MAGNITUDE WHICH IS A FUNCTION OF THE DURATION OF SAID DIFFERENCE SIGNAL, SAID SECOND DELAYING MEANS BEING COUPLED TO RECEIVE SAID BIASING VOLTAGE AND RESPONDING THERETO TO CHANGE THE DURATION OF SAID SECOND DELAY PERIOD AS A FUNCTION OF THE DURATION OF SAID DIFFERENCE SIGNAL, THE CHANGE IN DURATION OF SAID SECOND DELAY PERIOD BEING OF A SENSE TO MINIMIZE SAID DIFFERENCE SIGNAL, MEANS FOR COUPLING SAID RESULTANT SIGNAL TO SAID INPUT GATE TO DISABLE SAID GATE FOR THE DURATION OF SAID RESULTANT SIGNAL, MEANS RESPONSIVE TO SAID RESULTANT SIGNAL FOR PRODUCING A RAMP-TYPE SIGNAL HAVING A DURATION AND A MAGNITUDE WHICH ARE FUNCTIONS OF THE TIME INTERVAL BETWEEN THE OCCURRENCES OF SUCCESSIVE RESULTANT SIGNALS, AND DETECTING MEANS COUPLED TO RECEIVE SAID RAMP-TYPE SIGNAL AND SAID RECEIVED PULSES TO PRODUCE AN OUTPUT SIGNAL WHICH IS A FUNCTION OF THE TIME OF OCCURRENCE OF A NEWLY RECEIVED PULSE RELATIVE TO A RAMP-TYPE SIGNAL SIMULTANEOUSLY COUPLED TO SAID DETECTING MEANS.