Measurement and control from frequency to phase based on virtual signal reconstruction.

A virtual reconstruction method of directly capturing phase information between different nominal frequency signals, without frequency transformation, is proposed in this paper, building a virtual standard frequency signal whose frequency equals the measured nominal frequency and then making continuous comparison in the measuring gate which is synchronous with multiple periods between the measured signal and the reference frequency signal. Phase variations of the measured signal in every continuous gate are determined, and continuous phase-measuring is implemented. The experimental result verifies this special method for directly processing the phase difference between different nominal frequency signals and realizes a comparison precision of 10-17/day in a wide range.