Coherent heterodyne FMCW lidar based on combined single/double sideband modulation detection technology

•We improve the ranging accuracy of FMCW systems using the spectral refinement method CZT.•The use of spectral refinement methods will bring instability in the ranging results, and the experimental system constructed improves the ranging stability of the FMCW lidar when performing high-precision ranging.•Accurately measures the speed of target motion using binomial fitting.•The constructed experimental system can determine the direction of motion when measuring the motion state of a moving target.