Non-cooperative target ranging technique based on optical frequency comb correction

Frequency-modulated continuous-wave (FMCW) laser interferometric ranging technology, characterized by strong anti-interference capability and no need for cooperative reflection targets, holds significant application value in large-space precision measurements. Enhancing its accuracy and stability is currently a core demand. This paper proposes an innovative FMCW ranging scheme: integrating femtosecond optical frequency comb calibration with a two-speed frequency sweeping strategy. System calibration is completed via the slow-speed sweep, while precision ranging is achieved through dual fast-speed sweeps, simultaneously addressing the issue of frequency sweep nonlinearity and Doppler vibration. While improving measurement speed, the ranging standard deviation within 38 m is reduced to below 7 µm, providing what we believe is a new path for optimizing FMCW ranging accuracy.