Advanced Digital Spectroscopy Channel for Signal Analysis and Diagnosis Based on SoC FPGA

Abstract

This article presents the design and implementation of a data acquisition system for a digital spectroscopy channel based on a field-programmable gate array (FPGA) integrated in a system-on-chip (SoC). The system integrates two independent modules: a pulse mulator and a pulse analyzer. The emulator generates signals by synthesizing pulses using Poisson-distributed arrival times and Gaussian-distributed amplitudes, as well as custom configurations to simulate effects such as pile-up. The analyzer captures and processes these signals, extracting key parameters such as pulse height and arrival time. It also includes FPGA hardware processing with customizable and configurable filters, speeding up processing before transferring the results to the SoC for storage and visualization. The system is implemented on a low-cost platform based on an AMD Xilinx Zynq 7010 SoC, with programmable FPGA logic and an ARM Cortex-A9 processor running Linux Ubuntu. This SoC FPGA enables fast signal processing and extraction of key parameters and histogram generation in the FPGA, while the microprocessor manages communication and control tasks. A client–server software model based on a TCP/IP architecture and using standard commands for programmable instruments (SCPI) commands facilitates remote control and data visualization through a Python-based graphical interface. By leveraging the emulator and analyzer in a closed-loop configuration, the system enables self-testing and calibration, allowing fine-tuning of delays and signal losses through comparative analysis of both modules. In addition, the emulator can operate independently as a configurable pulse source for applications in nuclear engineering, particle accelerators, and medical engineering. This setup eliminates the need for radioactive sources, enabling precise and safe analysis in spectroscopy applications. Laboratory tests and validation under real radiation conditions, including comparison with commercial systems, demonstrated the system’s accuracy and flexibility, highlighting its usefulness in spectroscopy. The integration of both modules into a single device provides flexibility and cost reduction, with performance competitive with state-of-the-art digital spectroscopy systems reviewed.