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A high resolution FMCW Lidar system based on a phase-diverse self-homodyne coherent receiver is demonstrated. Using the same linearly chirped waveform for both the transmitted lidar signal and the local oscillator, the self-homodyne coherent receiver performs frequency de-chirping in the photodiodes which significantly simplifies the task of signal processing, and the required receiver bandwidth can be much lower than the signal chirping bandwidth. While only amplitude modulation is required in the lidar transmitter, phase-diverse coherent receiver allows simultaneous detection of target range and velocity through the spectrum of the de-chirped complex waveform. Multi-target detection is also demonstrated experimentally.
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Few-mode frequency-modulated LiDAR receivers
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.
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- 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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