Fig. 1. Measurement principle of FMCW lidar. (a) Simplified schematic diagram of measurement principle; (b) time-frequency diagrams of local oscillator signal E_LO and received echo signal E_S

Fig. 2. Intermediate frequency spectra at various velocities of target. (a1)-(f1) Theoretical results; (a2)-(f2) simulation results

Fig. 3. Calculation process of intermediate frequency based on self-convolution of spectrum

Fig. 4. Schematic diagram of FMCW lidar

Fig. 5. Simulation results of distance and velocity measurements based on traditional peak-searching method. (a) Simulation results of distance measurements; (b) simulation results of velocity measurements

Fig. 6. Self-convolution process of intermediate frequency spectrum. (a) Intermediate frequency spectrum; (b) self-convolution of intermediate frequency spectrum

Fig. 7. Simulation results of distance and velocity measurements based on proposed algorithm. (a1)-(c1) Simulation results of distance measurements; (a2)-(c2) simulation results of velocity measurements

Fig. 8. Simulation results of multi-target measurement. (a) Intermediate frequency spectrum; (b) intermediate frequency spectrum of upper sideband; (c) self-convolution of intermediate frequency spectrum; (d1),(d2) simulation results of distance and velocity measurements of target 1; (e1),(e2) simulation results of distance and velocity measurements of target 2; (f1),(f2) simulation results of distance and velocity measurements of target 3