Construction of 4-D FMCW LiDAR images using narrow linewidth extended cavity DBR laser with highly linear wavelength sweeping

A FMCW LiDAR system of extended cavity distributed Bragg grating (DBR) lasers, on an InP generic foundry platform, is established with a narrow linewidth of ≈ 25 kHz. Meanwhile, utilizing the coupled phase modulator in the reverse-bias configuration, highly linear wavelength sweeping is demonstrated without the need for laser driving with a pre-distorted waveform. Real-time 4-D images (up to 1 fps) of the slow-moving object (10 mm/sec) can be directly constructed at the baseband with a central frequency as low as 100 kHz and a small Doppler shift, rather than up-conversion to an intermediate frequency to exclude flicker noise. The proposed LiDAR architecture based on the InP generic foundry shows the potential in a monolithically integrated photonic platform for compact 4-D FMCW systems.