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Published on: March 20, 2017
Signal and noise transfer in spatiotemporal quantum-based imaging systems.
Reza Akbarpour1, Saul N Friedman, Jeffrey H Siewerdsen
1Robarts Research Institute, Department of Medical Biophysics, University of Western Ontario, 100 Perth Drive,London, Ontario, Canada.
Summary
This study extends Fourier transfer theory to the temporal domain for quantum imaging noise analysis. It reveals how temporal lag in quantum imaging systems affects spatial and temporal noise, reducing overall image noise.
Area of Science:
- Medical Imaging Physics
- Quantum Imaging Systems
- Signal Processing
Background:
- Understanding noise is crucial for accurate quantum-based medical imaging.
- Existing models often focus on spatial noise, neglecting temporal dynamics.
Purpose of the Study:
- To extend Fourier-based transfer theory into the temporal domain.
- To analyze spatial and temporal noise processes in quantum imaging systems.
- To model the impact of temporal lag on image noise.
Main Methods:
- Developed a temporal domain extension of Fourier transfer theory.
- Represented lag as temporal scatter using a probability density function.
- Derived expressions for spatiotemporal Wiener noise power spectrum transfer through quantum gain and scatter.
Main Results:
- Temporal lag introduces noise correlations in the temporal domain.
- The effect of lag depends on both spatial and temporal physical processes.
- A fluoroscopic system model showed noise reduction similar to Wagner's information bandwidth integral.
Conclusions:
- The temporal domain analysis provides a comprehensive understanding of noise in quantum imaging.
- Temporal lag can be leveraged to reduce image noise in systems like fluoroscopy.
- This framework is applicable to various quantum-based medical imaging modalities.
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