Narrowband parallel coherent LiDAR with frequency interleaving

TL;DR

This paper introduces a narrowband parallel coherent LiDAR with frequency interleaving that achieves high-precision 3D imaging at low complexity and cost, enabling scalable and efficient LiDAR systems.

Contribution

It proposes a novel frequency-interleaving architecture for coherent LiDAR that reduces bandwidth and complexity while maintaining high performance.

Findings

Ranging precision of 0.49 mm approaching shot noise limit

Power sensitivity of -95 dBm (~9 photons)

Parallel 3D imaging at 10 Mpixel/s with 2 cm accuracy

Abstract

The high demand for 3D imaging in intelligent robotics is motivating the advances of coherent LiDARs towards high performances with low complexity/cost. However, the current coherent LiDARs suffer from the tight coupling between the high ranging-imaging performance and the high complexity/cost. Herein, we propose a narrowband parallel coherent LiDAR with frequency-interleaving architecture. The LiDAR architecture utilizes narrowband signals for ranging, and interleaves multi-channel sparse and narrowband signals in frequency domain at the receiving end to significantly reduce the required bandwidth and the number of detection branches, facilitating massive parallelization with low system complexity/cost. In experiments, a ranging precision of 0.49 mm that approaches the shot noise limit, and a power sensitivity of -95 dBm (~9 photons) are achieved. Parallel 3D imaging with an equivalent imaging rate of 10 Mpixel/s and a 2 cm ranging precision is also demonstrated using only two 150 MHz receiving branches. With these desirable properties, this new LiDAR opens an avenue for the LiDAR ecosystem.