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Updated: Jul 14, 2026
07:01
Frequency Mixing Magnetic Detection Scanner for Imaging Magnetic Particles in Planar Samples
Published on: June 9, 2016
Four-channel magnetic resonance imaging receiver using frequency domain multiplexing.
1Shanghai Key Laboratory of Functional Magnetic Resonance Imaging, East China Normal University, Shanghai 200062, People's Republic of China.
The Review of Scientific Instruments
|May 17, 2007
Summary
Frequency domain multiplexing offers a cost-effective solution for phased array magnetic resonance imaging (MRI) receivers. This technique reduces system size and cost by using a single analog-to-digital converter and multicarrier receiver, proving valuable for multichannel MRI systems.
Area of Science:
- Medical Imaging
- Electrical Engineering
- Signal Processing
Background:
- Traditional phased array MRI systems often rely on independent receiver chains, which can be bulky and expensive.
- The demand for high-density, multichannel receiver systems in MRI is increasing.
- Reducing the size and cost of MRI receiver hardware is crucial for wider accessibility.
Purpose of the Study:
- To detail an alternative technique for acquiring phased array magnetic resonance images using frequency domain multiplexing.
- To demonstrate the advantages of this method in reducing the size and cost of phased array receiver systems.
- To validate the performance of a practical implementation of this technique.
Main Methods:
- Implementation of a four-channel digital receiver utilizing frequency domain multiplexing.
- Integration with a single-chip multicarrier receiver and an analog-to-digital converter.
- Verification on a home-built 0.3 T magnetic resonance imaging system.
Main Results:
- Achieved crosstalk between channels below -60 dB.
- Observed phase fluctuations of approximately 1 degree.
- Confirmed no significant degradation in signal-to-noise ratio.
- Demonstrated reduced system size and cost compared to traditional methods.
Conclusions:
- Frequency domain multiplexing is a valuable and economical technique for phased array MRI.
- This method is particularly suitable for array coil systems requiring multichannel receivers where dynamic range is not critical.
- The implemented system offers high performance with reduced hardware complexity.
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