Coherent Pulse-Compression Lidar Based on 90-Degree Optical Hybrid

Area of Science:

• Optoelectronics
• Optical Engineering
• Remote Sensing

Background:

• Amplitude modulation (AM) lidar suffers from ranging fluctuations due to random phase differences.
• These fluctuations lead to low detection probabilities in traditional lidar systems.
• Accurate distance measurements are crucial for various remote sensing applications.

Purpose of the Study:

• To demonstrate a coherent pulse-compression lidar system utilizing a 90-degree optical hybrid.
• To enhance the detection probability and precision of lidar ranging.
• To stabilize ranging results by mitigating phase difference effects.

Main Methods:

• Implementation of a coherent pulse-compression lidar system.
• Integration of a 90-degree optical hybrid to generate orthogonal complementary signals.
• Experimental measurement of a target at approximately 65 meters.

Main Results:

• The 90-degree optical hybrid stabilized ranging results, increasing detection probability from 65% to 99.88%.
• Ranging precision was significantly improved, from 0.42 meters to 0.27 meters.
• The system effectively mitigated phase difference issues inherent in AM lidar.

Conclusions:

• The demonstrated 90-degree optical hybrid approach is highly effective for improving lidar performance.
• This technique offers a robust solution for enhancing detection probability and precision in coherent lidar systems.
• The findings have implications for advancing accurate and reliable distance measurement technologies.