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Updated: Jun 28, 2026
07:33
Quantifying Mixing using Magnetic Resonance Imaging
Published on: January 25, 2012
[Algorithm of digital demodulation and filtering in MRI spectrometers]
Wen-Yu Pan1, Zheng-Min Liu, He-Qin Zhou
1Department of Automation, University of Science and Technology of China, Hefei, 230027. panly@mail.ustc.edu.cn
Summary
This thesis presents a digital demodulation and filtering algorithm for MRI spectrometer consoles. The method enhances processing speed and filtering effects while reducing data size for digital MR signal processing.
Area of Science:
- Digital signal processing
- Magnetic Resonance Imaging (MRI) hardware design
Context:
- Radio Frequency (RF) receiver design in digital MRI spectrometer consoles requires efficient signal processing.
- High-frequency carrier wave demodulation and filtering are critical steps.
Purpose:
- To present a digital demodulation and filtering algorithm for RF receivers in digital MRI spectrometer consoles.
- To improve processing speed and filtering effectiveness.
- To reduce data size of MR signals.
Summary:
- MR signals are digitized via an A/D converter and quadrature-demodulated.
- Cascaded filtering and decimation are performed using Cascaded Integrator-Comb (CIC) filter, half-band filter, and linear phase Finite Impulse Response (FIR) filter.
- The algorithm demonstrates effective and practical application in a permanent magnet MRI system.
Impact:
- Achieves satisfying processing speed and filtering effects.
- Significantly reduces data size, optimizing storage and transmission.
- Validates the algorithm's effectiveness and practicality through experimental results on a permanent magnet MRI system.
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