Frequency modulation communication system having automatic frequency deviation adjustng means

Claim 1

A FREQUENCY MODULATION COMMUNICATION SYSTEM COMPRISING A FIRST STATION AND A SECOND STATION, A BILATERAL TRANSMISSION PATH BETWEEN SAID STATIONS THE LOSS INTRODUCED THEREBY BEING SUBJECT TO VARIATIONS, A TRANSMITTER AND RECEIVER LOCATED AT EACH OF SAID STATIONS AND ACCESSIBLE TO SAID TRANSMISSION PATH, A FIRST SOURCE OF SIGNALS TO BE CONVEYED FROM SAID FIRST STATION TO SAID SECOND STATION CONNECTED TO THE TRANSMITTER LOCATED AT SAID FIRST STATION, MEANS FOR EXTRACTING SAID FIRST SIGNAL FROM THE RECEIVER AT SAID SECOND STATION, A SECOND SOURCE OF SIGNALS TO BE CONVEYED FROM SAID SECOND STATION TO SAID FIRST STATION CONNECTED TO THE TRANSMITTER AT SAID SECOND STATION, MEANS AVAILABLE AT SAID FIRST STATION TO EXTRACT SAID SECOND SIGNAL AT THE RECEIVER OF SAID FIRST STATION, MEANS FOR DERIVING AN INDICATION FOR ALTERING THE FREQUENCY DEVIATION OF THE SAID INDICATION FOR ALTERING THE FREQUENY DEVIATION OF THE SAID INDICATION FOR ALTERING THE FREQUENCY DEVIATION OF THE FREQUENCY MODULATED SIGNAL GENERATED BY SAID TRANSMITTER AT SAID FIRST STATION TO MAINTAIN EQUALITY BETWEEN THE SIGNAL-TO-THERMAL NOISE RATIO AND THE SIGNAL-TO-MODULATION NOISE RATIO AT THE OUTPUT OF SAID RECEIVER AT SAID SECOND STATION.