High-speed 3D imaging using a chaos lidar system

Abstract

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.

Parallel random LiDAR with spatial multiplexing of a many-mode laser

“…Compared to spectral demultiplexing, spatial demultiplexing is able to provide many channels without sacrificing the bandwidth and resolution of the individual channel. Moreover, our source has a intrinsic bandwidth of 100 GHz and can thus generate simultaneously several independent channels in various RF bands of interest for RADAR, such as the K u band (12-18 GHz), the K a band (27)(28)(29)(30)(31)(32)(33)(34)(35)(36)(37)(38)(39)(40) and the W band (75-110 GHz), where the last is not accessible with temporal chaos from semiconductor lasers under optical feedback. Without those trade-offs, our parallel ranging scheme based on a high-power many-mode laser will facilitate high-speed 3D sensing and imaging.…”

“…Compared to pseudo-random sequences created by optical modulators, intensity fluctuations of chaotic lasers [26][27][28] and thermal emitters [29], as well as stochastic spontaneous emission events [30,31], can provide true random waveforms with higher modulation speed. In particular, a chaotic semiconductor laser with radio-frequency (RF) bandwidth ∼10 GHz provides centimeter resolution for long-distance ranging [27,[32][33][34][35]. * *hui.cao@yale.edu However, it is technically challenging to make a large array of chaotic lasers with distinct dynamics for parallel LiDAR.…”

3-D Multi-Input Multi-Output (MIMO) Pulsed Chaos Lidar Based on Time-Division Multiplexing

“…We used a power meter (PM) to monitor ξ fb and an isolator (ISO) to avoid any unwanted feedback. To better match with the detector bandwidth, we used a fiber Bragg grating (FGB; IXblue IXC-FBG-PS-1550-1-ATH-PM-C, linewidth <1 GHz) to reduce the linewidths of the chaos waveforms and thus enhance the modulation depth for better detection capability [29].…”

“…In the large FOV scan within the blue box, the FOV is 20 × 20 degrees, the image resolution is 128 × 128 pixels, and the angular resolution is 0.16 degrees both horizontally and vertically. To have such a large FOV, in this channel a quadrant APD (Idealphotonics QPD-1000) was used in the transceiver module to increase the detection area [29]. As can be seen, the posture of the person, the iron cabinet on the right, the optical table on the left, the cardboard, and the boxes behind are all clearly depicted.…”

“…To take advantage of both the pulsed and modulated CW lidars, we proposed and studied a 3D pulsed chaos lidar system that utilizes chaos-modulated pulses to improve the SNR [24]- [27]. By employing a pulsed master oscillation power amplifier (MOPA) scheme and quadrant avalanche photodetectors (APDs) [28], [29], high-speed 3D imaging at a throughput of 100 kHz, a frame rate of 10 Hz, and a field-of-view (FOV) of 24.5 × 11.5 degrees have been demonstrated. While the detection performance of the single-input single-output (SISO) chaos lidar system keeps being improved, its FOV is still limited by the mechanical turning angle of the micro-electro-mechanical system (MEMS) mirror and the physical parameters of the receiving optics.…”