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Measurement of Coherence Decay in GaMnAs Using Femtosecond Four-wave Mixing
Published on: December 3, 2013
Simulation of Algorithms for Pulse Timing in FPGAs.
Michael D Haselman1, Scott Hauck, Thomas K Lewellen
1Dept. of Electrical Engineering, University of Washington, Seattle, WA 98195 USA.
IEEE Nuclear Science Symposium Conference Record. Nuclear Science Symposium
|January 31, 2009
Summary
Field Programmable Gate Arrays (FPGAs) enable precise pulse timing for pre-clinical positron emission tomography (PET) scanners. Simulations optimize algorithms for timing resolution below analog-to-digital converter sampling periods.
Area of Science:
- Medical Imaging
- Digital Signal Processing
- Embedded Systems
Background:
- Modern Field Programmable Gate Arrays (FPGAs) offer high clock rates and cost-effectiveness for signal processing.
- FPGAs are crucial for developing advanced electronics in pre-clinical positron emission tomography (PET) scanner systems.
- Accurate pulse timing is essential for improving the performance of PET scanners.
Purpose of the Study:
- To develop and simulate advanced pulse timing techniques for pre-clinical PET scanners.
- To achieve timing resolution significantly below the analog-to-digital converter (ADC) sampling period.
- To optimize algorithm parameters using MATLAB simulations before hardware implementation.
Main Methods:
- Simulating pulse timing algorithms in MATLAB using real data.
- Investigating various filter designs and ADC sampling rates.
- Developing and evaluating a least squares fitting algorithm and a leading edge detector for PMT pulses.
Main Results:
- Demonstrated the feasibility of achieving timing resolution below the ADC sampling period using pulse fitting techniques.
- Identified optimal parameters for timing algorithms through MATLAB simulations.
- Compared the performance of a least squares fitting algorithm against a leading edge detector.
Conclusions:
- FPGA-based pulse timing offers a viable and cost-effective solution for next-generation pre-clinical PET scanners.
- Simulations in MATLAB are effective for optimizing timing algorithms and parameters prior to hardware implementation.
- Pulse fitting techniques show promise for enhancing timing resolution in PET systems, even with lower sampling rate ADCs.
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