We investigated the characteristics of chaos-modulated pulses amplified by a pulsed master oscillator power amplifier (MOPA) for application in a new chaos lidar system in this study. Compared with the loss modulation applied in a continuous-wave (CW) time-gating scheme, the pulsed MOPA scheme could generate chaos-modulated pulses with much higher peak power, resulting in an improved peak-to-standard deviation of sidelobe level (PSLstd) in correlation-based lidar detection. When the pulsed MOPA scheme was applied at a duty cycle of 0.1% and pulse repetition frequency of 20 kHz, which correspond to specifications compliant with eye safety regulations, it outperformed the CW time-gating scheme with respect to PSLstd by 15 dB. For the first time, we applied the chaos lidar system with the pulsed MOPA scheme to execute high-resolution, high-precision three-dimensional (3D) face profiling from a distance of 5 m. We also added the corresponding PSLstd value to each pixel in the point clouds to generate false-color images; thus, we obtained 3D images of a scene with multiple objects at a range of up to 20 m.

In this study, we propose and evaluate a 3D multi-input multi-output (MIMO) pulsed chaos lidar based on time-division multiplexing. By time-gating a chaos waveform sequentially at different times, chaos-modulated pulses for different channels that are uncorrelated with each other can be generated. To quantitatively evaluate the anti-interference/jamming capability, we investigated the detection performance of the MIMO chaos lidar under different jamming strengths and overlapped ratios between the jamming and the signal pulses. The overall detection probabilities of the chaos lidar and a conventional time-digital-converter-based pulsed lidar under the influence of interference/jamming were compared and we found that the chaos lidar exhibits strong resistance to the interference/jamming. Employing the 3D MIMO chaos lidar developed, we demonstrate 3D imaging under the influence of interference/jamming. By simultaneously scanning 2 different channels with overlapped field-of-views (FOVs), 3D images with large-FOV/low-resolution and small-FOV/high-resolution were obtained at the same time.

We characterize a new chaos lidar system configuration and demonstrate its capability for high-speed 3D imaging. Compared with a homodyned scheme employing single-element avalanche photodetectors (APDs), the proposed scheme utilizes a fiber Bragg grating and quadrant APDs to substantially increase the system throughput, frame rate, and field-of-view. By quantitatively analyzing the signal-to-noise ratio, peak-to-standard deviation of the sidelobe level, precision, and detection probability, we show that the proposed scheme has better detection performance suitable for practical applications. To show the feasibility of the chaos lidar system, while under the constrain of eye-safe regulation, we demonstrate high-speed 3D imaging with indoor and outdoor scenes at a throughput of 100 kHz, a frame rate of 10 Hz, and a FOV of 24.5$$^\circ $$ ∘ $$\times $$ × 11.5$$^\circ $$ ∘ for the first time.

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