Comparison between the FMCWs in microwave domain generated by a pure electrical equipment and a hybrid opto-electronic system

Frequency modulated continuous wave (FMCW) LiDAR -based 3D imaging has significantly advanced in resolution and frame rate. External modulation provides superior frequency-swept slopes but relies on high-quality RF signals. While Arbitrary Waveform Generators (AWGs) meet performance requirements, their high cost and bulkiness limit practical application. This paper proposes a hybrid optoelectronic system using coherent optical injection into a semiconductor laser. Exploiting the period-one oscillation state enables frequency-tunable microwave generation. To counteract nonlinearities, an adaptive predistortion algorithm was evaluated via numerical simulations. Results show linearity improved by four orders of magnitude, reducing nonlinearity from 10-3 to 10-7. This system provides a compact, competitive alternative to expensive digital equipment for LiDAR applications.