Noise Analysis for Correlation-Assisted Direct Time-of-Flight

Area of Science:

• Photonics and Sensor Technology
• Integrated Circuit Design

Background:

• Direct time-of-flight (dToF) sensors are crucial for applications requiring precise distance measurements.
• Existing dToF pixels face challenges with power consumption, ambient light noise, and systematic errors.
• Correlation-assisted direct time-of-flight (CA-dToF) pixels offer a promising alternative with enhanced features.

Purpose of the Study:

• To investigate the robustness of the CA-dToF pixel against various noise sources.
• To identify and analyze performance limitations, including SPAD deadtime and component mismatches.
• To propose methods for enhancing the CA-dToF pixel's reliability and implementation.

Main Methods:

• Systematic error analysis of the CA-dToF pixel architecture.
• Investigation of noise impact: timing jitter, kTC noise, switching noise, and photon shot noise.
• Evaluation of limitations: SPAD deadtime, source follower gain mismatch, and offset.

Main Results:

• The CA-dToF pixel demonstrates effectiveness in low power consumption and ambient shot noise suppression.
• Identified key systematic errors and their impact on dToF measurement accuracy.
• Quantified the influence of timing jitter, kTC noise, switching noise, and photon shot noise.

Conclusions:

• The CA-dToF pixel presents a viable solution for advanced time-of-flight applications.
• Understanding and mitigating identified systematic errors are crucial for optimal performance.
• Proposed solutions can significantly enhance the reliability and practical implementation of CA-dToF pixels.