Fig. 2

Diagram of comb modes for the OMFCs. The dual combs generated by the OPA processes share a same tooth inherited from the common narrow line width CW laser but with different frequency intervals. The heterodyne comb teeth with zero-offset carrier frequency are all evenly spaced with repetition rate offset ∆ in rf domain. The adaptive sampling signal can be expressed as f_beat = n∆ and used to sample the heterodyne signal for strictly eliminating the repetition rate deviations