Nuclear Radiation Pulse Amplitude Digitization via Time Width Conversion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional methods for amplitude digitization of nuclear radiation pulses are inadequate for systems with a large number of channels, as they require high-speed analog-to-digital converters (ADCs), leading to an unacceptable scale of electronic systems for parallel readout and digitization.
Innovation Solution
The method converts voltage amplitude values of nuclear radiation pulse signals into over-threshold time widths using time digital conversion technology, allowing for high-precision measurement without increasing the front-end readout circuit complexity, enabling a highly integrated multi-channel digitization system that can be implemented on a single-chip FPGA or ASIC.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional ADC method is used for amplitude digitization, then measurement precision is maintained, but device complexity and system scale become unacceptable for multi-channel parallel readout
Solution Approach 1:
The invention changes the parameter being measured from voltage amplitude to time width. By converting the amplitude measurement problem into a time width measurement problem, the system can use simple time-to-digital conversion instead of complex high-speed ADC, thereby reducing device complexity while maintaining measurement precision through the linear relationship between amplitude and time width
Solution Approach 2:
The invention replaces the electronic ADC conversion mechanism with a time-based measurement mechanism. Instead of using analog-to-digital conversion circuits, the system uses time width measurement (e.g., through constant fraction discrimination or leading edge discrimination) to represent amplitude information, substituting a simpler time measurement system for a complex voltage conversion system
2Measurement precision
If high-speed ADC is used for each channel, then amplitude digitization accuracy is achieved, but ease of operation and parallel readout capability deteriorate due to unacceptable system scale
Solution Approach 1:
The invention transforms the measurement parameter from voltage domain to time domain, enabling parallel readout through simple time width measurement. This parameter transformation allows multiple channels to be processed simultaneously without requiring complex high-speed ADCs, thereby improving parallel readout capability while maintaining digitization accuracy
Solution Approach 2:
The invention segments the measurement function into separate time width measurement units that can operate independently in parallel. Each channel can have its own simple time measurement unit, allowing simultaneous operation of multiple channels without interference, thus enhancing parallel readout capability and ease of operation
Data Source
Figure 1~2
Figure 3~4
Figure 5~6
AI summary
Disclosed are methods and systems for amplitude digitization of nuclear radiation pulses. The method includes: applying a constant fraction discrimination (CFD) timing process on a subject current signal and outputting a CFD timing signal; applying a shaping process on the subject current signal to obtain a subject shaped signal; comparing, from a time To, values taken at the same time by the subject shaped signal and a dynamic threshold signal, and taking a time Tot as an over-threshold time if the value of the dynamic threshold signal changes from less than the value of the subject shaped signal to not less than the value of the subject shaped signal at the time Tot, wherein a time length between the time To and the arrival time Td of the subject current signal is preset as ”T; converting a time length between the time Td and the time Tot into a digital quantity as a digitized value of the amplitude of the nuclear radiation pulse; wherein for any two subject shaped signals having amplitudes Vot1 and Vot2, respectively, the dynamic threshold signal satisfies an equation Tot �¢ 2 - To Vot �¢ 2 = Tot �¢ 1 - To Vot �¢ 1 , Tot1 represents an over-threshold time for one of the subject shaped signals compared with the dynamic threshold signal, and Tot2 represents an over-threshold time for the other of the subject shaped signals compared with the dynamic threshold signal.