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Time transfer method and system

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A Time Transfer Time Reverse Mirror (TT TRM) method and system includes a radio transceiver for transmitting a series of short pulses repeatedly at a period T and for receiving from a remote node a return signal that is a retransmission of the original signal at the same period T: a clock circuit for inputting a clock signal to the transceiver: and a computer for (i) computing and generating an imaginary time-reversed signal version of the original signal, (ii) comparing the return signal with the imaginary version, (iii) computing a delay between the return signal and the imaginary version that is substantially equal to twice the time difference between the two nodes, and (iv) applying the computed delay to a clock input calibration for a desired signal. The system includes time transfer using the ionospheric reflection (refraction), producing precise synchronization among remote nodes beyond the line-of-sight and thus without necessitating GPS or communication satellites.

Paek, Eung Gi; Choe, Joon Y.
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Sensors and Measurement
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Grant time: 
686 days
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