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Hyperpolarized Xenon for NMR and MRI Applications

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Published on: September 6, 2012

PIN diode driver for NMR and MRI.

D H Johansen¹, M M Albannay¹, J R Petersen¹

¹Technical University of Denmark, Department of Electrical Engineering, Ørsteds Plads 349, Kgs. Lyngby, Denmark.

Journal of Magnetic Resonance (San Diego, Calif. : 1997)

|February 10, 2019

Summary

This summary is machine-generated.

A new PIN diode driver enables custom radiofrequency (RF) switching circuits for magnetic resonance (MR) systems. This driver offers fast switching times, enhancing custom coil design for both nuclear magnetic resonance (NMR) spectrometers and magnetic resonance imaging (MRI) scanners.

Keywords:

Active decoupling Driver MRI NMR PIN diode Q-spoiling Switch TR switching

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Area of Science:

Magnetic Resonance Engineering
Radiofrequency Electronics
Instrumentation Design

Background:

Designing custom coils for Nuclear Magnetic Resonance (NMR) and Magnetic Resonance Imaging (MRI) often requires non-standard transmit-receive (T/R) switches and Q-spoiling circuits.
Commercial NMR and MRI systems have limited reconfigurability in their built-in drivers, hindering control of custom RF switching components.

Purpose of the Study:

To present a versatile PIN diode driver capable of operating in both NMR spectrometers and MRI scanners.
To provide a solution for controlling custom T/R switches and Q-spoiling circuits in magnetic resonance systems.

Main Methods:

Development of a PIN diode driver using readily available discrete electronic components.
Characterization of the driver's switching performance for reverse (transmit off) and forward (transmit on) bias states.

Main Results:

The PIN diode driver achieved switching times of 2 μs for the reverse bias state and 0.4 μs for the forward bias state.
The driver demonstrated functionality in both MRI and NMR environments.

Conclusions:

The developed PIN diode driver facilitates a greater degree of customization for RF switching circuits in magnetic resonance systems.
This driver is a valuable tool for researchers and engineers designing custom coils for NMR and MRI applications.