A novel scheme for processing FMCW-ladar data acquired with low sampling rate

The coherent ladar has been used for both the commercial and military applications, including the range measurement, range-resolved velocity and vibration measurement, range imaging, and synthetic aperture ladar imaging (Beck et al. Citation2005; Gao, Maurice, and H. Rongqing Citation2012; Klotz, Halmos, and Bulot Citation2013; Hu et al. Citation2018; Salas Citation2021). One of the key capabilities required of the coherent ladar system is to provide the fine range resolution with a high signal-to-noise ratio (SNR). From the radar/ladar community, the FMCW-ladar system can provide the large bandwidth and high SNR. In comparison to the pulsed ladar system, FMCW-ladar transmits chirp with long duration and large bandwidth. Besides, the FMCW-ladar benefits from its lower peak power, smaller volume, and lower cost. Thus, the FMCW-ladar system has been widely used in many applications, such as the remote precision range, range imaging, and SAL imaging (Karlsson and Olsson Citation1999; Barber et al. Citation2013; Barber and Dahl Citation2014; Li et al. Citation2017).