FPGA-based dual-channel readout and centroid algorithm for cross-strip anode photon detectors

Area of Science:

• Photonics and Detector Technology
• Digital Signal Processing
• High-Resolution Imaging Systems

Background:

• Crossed-strip anode single-photon detectors are vital for 2D localization in optical imaging.
• Conventional readout architectures face bandwidth and latency limitations at high count rates, hindering real-time analysis.
• Efficient centroid computation is crucial for accurate spatial reconstruction in photon imaging.

Purpose of the Study:

• To develop an FPGA-based dual-channel signal processing architecture for high-speed centroid extraction.
• To overcome bandwidth and latency limitations in conventional readout schemes.
• To enhance real-time processing capabilities for crossed-strip anode detectors.

Main Methods:

• Integration of an application-specific integrated circuit charge-sensitive preamplifier and a 14-bit ADC for signal digitization.
• Implementation of parallel fast and slow signal processing channels for triggering, pileup rejection, and peak extraction.
• Utilization of a sliding-window approach and a symmetric weighted centroid algorithm for spatial coordinate reconstruction.

Main Results:

• The proposed architecture achieves a stable event rate exceeding 15 MHz.
• Demonstrated spatial resolution of 20.16 line pairs per millimeter (lp/mm).
• Improved centroid accuracy and processing throughput compared to conventional methods.

Conclusions:

• The FPGA-based dual-channel architecture effectively addresses limitations in high count-rate photon imaging.
• The system enables real-time, high-resolution photon imaging applications.
• Validated feasibility for advanced optical imaging systems requiring precise event localization.