Fig. 1. Structure diagram of dual-path FMCW laser ranging system

Fig. 2. Structural diagram of FMCW laser ranging system based on FWM effect

Fig. 3. Time-frequency diagram for generation of FWM effect

Fig. 4. Spectra obtained by zero-padded FFT of equispaced-phase resampling data at vibration frequency of 2 Hz. (a) Non-vibration environment, S1; (b) non-vibration environment, S2; (c) vibration environment, S1; (d) vibration environment, S2

Fig. 5. Spectra obtained by zero-padded FFT of S3. (a) Non-vibration environment; (b) vibration environment

Fig. 6. Absolute errors of measurement before and after compensation. (a) Before compensation; (b) after compensation