Ring around transceiver

A communications system comprising:

• a first transceiver comprising (a) a first signal source for producing a first output signal having either a first frequency or a second frequency;
• (b) means for controlling said signal source to cause said first output signal to have either said first or said second frequency;
• (c) means for receiving an input signal from a second signal source and for mixing said input signal with said first output signal of said first signal source to produce a first difference frequency determined by the relative difference between the frequency of said received input signal and the frequency of said first output signal;
• (d) first detector means responsive to said first difference frequency to cause said means for controlling said first signal source to cause said first output signal to shift from said first frequency to said second frequency;
• a second transceiver comprising (e) a second signal source for producing a second output signal having either a third frequency or a fourth frequency;
• (f) means for controlling said second signal source to cause said second output signal to have either said third or said fourth frequency;
• (g) means for receiving the first output signal produced by said first signal source in said first transceiver and for mixing said received signal with said second output signal of said second signal source to produce a second difference frequency determined by the relative difference between said received signal and said second output signal;
• (h) second detector means responsive to said second difference frequency to cause said output signal produced by said second signal source to change from said third frequency to said fourth frequency, said change from said third to said fourth frequency causing a change in said first difference signal in said first transceiver thus defining a feedback data path between said first and said second transceiver.

A communications system comprising:

• a first transceiver comprising (a) a first signal source for producing an output signal having a first center frequency;
• (b) means for controlling said signal source to cause a deviation from said first center frequency;
• (c) means for receiving an input signal from a second signal source and for mixing said signal with said output signal of said first signal source to produce a first difference frequency determined by the relative difference between the frequency of said received signal and the frequency of said first output signal;
• (d) first detector means responsive to said first difference frequency to cause said means for controlling said first signal source produce a control signal to cause said predetermined deviation from said first center frequency;
• a second transceiver comprising (e) a second signal source for producing a second output signal having a second center frequency;
• (f) means for controlling said second signal source to cause a deviation from said second center frequency;
• (g) means for receiving said first output signal produced by said first signal source in said first transceiver and for mixing said received signal with said second output signal of said second signal source to produce a second difference frequency determined by the relative difference between said received signal and said second output signal;
• (h) second detector means responsive to said second difference frequency to produce a control signal to cause said deviation from said second center frequency, said deviation from said second center frequency causing a change in said first difference signal in said first transceiver and thereby defining a feedback data path between said first and said second transceiver.