Dual Interpolating Counter Architecture for Atomic Clock Comparison

This paper deals with an accurate time transfer and atomic clocks comparison in a geographically distant locations utilizing the optical lines. A new dual interpolating counter architecture for the clock comparison over an optical network is presented, especially utilizing dense wavelength division multi-plexing (DWDM). There are described the time transfer method and the details of the interpolating counter implementation (the interpolator feed and the run time interpolator calibration). Experiences with the current embedded time interval counter design in the FPGA are presented as well.