Integrated polarization-diverse FMCW LiDAR with real-time CFAR for high-reliability long-range detection.

Area of Science:

• Photonics and Optical Engineering
• Remote Sensing Technologies
• Signal Processing

Background:

• Frequency Modulated Continuous Wave (FMCW) LiDAR provides interference immunity and simultaneous distance-velocity measurement.
• Challenges in long-range, low-reflectivity detection include polarization fading, reduced return power, bandwidth limits, and system noise.

Purpose of the Study:

• To enhance the detection reliability of FMCW LiDAR systems.
• To overcome limitations in long-range and low-reflectivity target detection.

Main Methods:

• Development of a silicon-photonic polarization-diverse coherent receiver to utilize both signal polarization states.
• Implementation of a pipeline real-time constant false-alarm rate (CFAR) algorithm for robust peak detection.
• Experimental validation of the integrated system performance.

Main Results:

• Polarization-diverse detection and CFAR significantly increased detection probability from 43.5% to 97% for a 200m, 10% reflectivity target.
• The system achieved real-time 4D imaging at a rate of 100,000 points per second.
• Reduced polarization-induced fading and improved signal-to-noise ratio under challenging conditions.

Conclusions:

• The integrated polarization-diverse receiver and CFAR processor substantially improve FMCW LiDAR performance.
• This approach offers a robust solution for reliable long-range and low-reflectivity target detection.
• The developed system demonstrates enhanced detection reliability for integrated FMCW LiDAR applications.