Solid-state light-detection-and-ranging (LiDAR) sensors based on integrated optical phased arrays (OPAs) have shown significant promise to reduce the cost, size, weight, and power consumption associated with LiDAR for autonomous systems. However, these OPA-based LiDAR systems typically operate by rastering a single beam, generating point clouds that constitute a significant amount of data and computational burden in the process. In this paper, we develop and experimentally demonstrate a novel multi-beam solid-state OPA-based LiDAR system capable of detecting and ranging multiple targets simultaneously, passively, and without rastering. Specifically, we develop the devices, subsystems, and system architectures to realize a solid-state frequency-modulated-continuous-wave (FMCW) LiDAR system that leverages a discrete-Fourier-transform star-coupler-based OPA as a receiver and a multi-beam splitter-tree-based OPA as a transmitter. Using this multi-beam LiDAR system, we demonstrate the simultaneous detection and ranging of two targets at two different cross-range positions without rastering. Through this work, we demonstrate a new spatially-adaptive sensing modality for solid-state LiDAR that enables improved spatial awareness and promises to reduce the data deluge associated with LiDAR in autonomous systems.
We present a few-mode frequency-modulated receiver for light detection and ranging (LiDAR). We show that using a few-mode local oscillator (LO) with spatial modes at different frequencies at the receiver can significantly improve the performance of the LiDAR detection range. A preferred receiver architecture features LO modes with unequal frequency separations based on optical orthogonal codes (OOC) to allow range detection via cross correlation. The required signal-to-noise ratio (SNR) for the frequency-modulated continuous wave (FMCW) LiDAR decreases with the number of LO modes. This receiver can have a potential impact in the area of automotive LiDARs.
more » « less- NSF-PAR ID:
- 10156681
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Optics Letters
- Volume:
- 45
- Issue:
- 11
- ISSN:
- 0146-9592; OPLEDP
- Format(s):
- Medium: X Size: Article No. 3127
- Size(s):
- Article No. 3127
- Sponsoring Org:
- National Science Foundation
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