Time-division radio relay communication system

Claim 1

TIME-SLOT DETERMINING MEANS FOR USE IN SUBSIDIARY STATIONS OF A TIME-DIVISION RADIO RELAY COMMUNICATION SYSTEM TYPICALLY COMPRISED OF A RELAY STATION, SUCH AS A SATELLITE RELAY STATION, POSITIONED AT AN APPRECIABLE DISTANCE FROM A PLURALITY OF GROUND STATIONS WHICH ARE LOCATED WITHIN THE SERVICE AREA OF SAID RELAY STATION AND WHICH INTERCHANGE RELAYED RADIO COMMUNICATION AT THE SUBSTANTIALLY EQUAL FREQUENCY BAND BY USING SAID RELAY STATION IN COMMON BUT AT RESPECTIVELY DIFFERENT PREDETERMINED TIME SLOTS, CHARACTERIZED IN THAT SAID GROUND STATIONS ARE COMPOSED OF A PLURALITY OF SUBSIDIARY STATIONS AND A MASTER STATION FOR SENDING OUT TO SAID RELAY STATION AT A PREDETERMINED REPETITION FREQUENCY A TRANSMITTER SIGNAL COMPRISING BOTH A SYNCHRONIZING SIGNAL SERVING AS THE REFERENCE OF SAID TIME SLOTS AND A SATELLITE-POSITION-REPRESENTING SIGNAL; AND A PLURALITY OF SUBSIDIARY STATIONS, SAID TIME-SLOT DETERMINING MEANS COMPRISING: FIRST MEANS FOR SENDING OUT SEARCH PULSES AT TIME POINTS DETERMINED BY A SYNCHRONIZING SIGNAL AND SATELLITEPOSITION-REPRESENTING SIGNAL RECEIVED FROM THE MASTER STATION THROUGH SAID RELAY STATION AND BY THE INFORMATION OBTAINED FROM AN EPHEMERIS; SECOND MEANS FOR DETECTING WHETHER EACH OF THE SEARCH PULSES HAS RETURNED THROUGH SAID RELAY STATION TO THE ASSOCIATED STATION PRIOR TO OR SUBSEQUENT TO A PREFERRED TIME POSITION PREDETERMINED WITH REFERENCE TO THE PULSES OF SAID SYNCHRONIZING SIGNAL; THIRD MEANS FOR CONTROLLING, IN RESPONSE TO THE RESULT OF THE DETECTION, THE TIME AT WHICH SUCCEEDING SEARCH PULSES ARE TRANSMITTED SO THAT EACH OF THESE PULSES MAY RETURN TO THE ASSOCIATED STATION AT THE SAID PREFERRED TIME POSITION; AND FOURTH MEANS FOR MAINTAINING SYNCHRONISM, ONCE DETECTED, WHERE THE SEARCH PULSES RETURN TO THE ASSOCIATED STATION AT THE RESPECTIVE PREFERRED TIME POSITIONS.