Adaptive aperture for Geiger mode avalanche photodiode flash ladar systems

Area of Science:

• Photonics and Optical Engineering
• Lidar Technology
• Solid-State Sensors

Background:

• Geiger-mode avalanche photodiode (GM-APD) flash lidar systems offer high sensitivity and simple design.
• Detection performance is limited by signal-to-noise ratio and absolute noise photon count.
• Accurate estimation of noise photons is crucial for optimizing GM-APD lidar performance.

Purpose of the Study:

• To develop a method for estimating noise photon numbers in GM-APD flash lidar under dark conditions.
• To introduce an adaptive aperture technique to mitigate background noise.
• To evaluate the impact of the adaptive aperture on detection probability, false alarm rate, and ranging accuracy.

Main Methods:

• Deduction of a hyperbolic approximation function to estimate noise photon count from false-firing percentage.
• Implementation of an adaptive aperture control based on the noise photon estimation.
• Simulations to assess the performance of the adaptive aperture method.

Main Results:

• The hyperbolic approximation accurately estimates noise photon numbers.
• The adaptive aperture method effectively reduces incoming background noise photons.
• Simulations demonstrate decreased false alarm probability across all scenarios.
• Detection probability is enhanced when signal strength exceeds noise levels.
• Average ranging error per frame is significantly reduced.

Conclusions:

• The proposed hyperbolic approximation provides a reliable method for noise photon estimation in GM-APD lidar.
• Adaptive aperture control is a viable strategy for improving GM-APD lidar performance by managing background noise.
• The adaptive aperture method offers a practical solution for enhancing lidar system accuracy and reliability.