System and method for improved rf system performance in mri systems

Patent metadata

Field	Value
Publication number	US-2017293003-A1
Application number	US-201715481415-A
Country	US
Kind code	A1
Filing date	Apr 6, 2017
Priority date	Apr 8, 2016
Publication date	Oct 12, 2017
Grant date	—

Abstract

An apparatus, a system, and a chip are provided for improving RF system performance in MRI systems. The apparatus includes a radio-frequency (RF) coil array disposed at least partially in a coil housing, where the RF coil array may include at least one coil configured to receive magnetic resonance (MR) RF signals. The apparatus also includes a mixer disposed in the coil housing and electronically connected to the RF coil array, where the mixer converts MR RF signals from the RF coil array to intermediate-frequency (IF) signals. An electronic amplifier is disposed in the coil housing. The electronic amplifier is electronically connected to the mixer and is configured to amplify IF signals from the mixer to amplified IF signals.

First claim

We claim:

1 . An apparatus, comprising:
a radio-frequency (RF) coil array disposed at least partially in a coil housing, the RF coil array comprising at least one coil configured to receive magnetic resonance (MR) RF signal; a mixer disposed in the coil housing and electronically connected to the RF coil array, wherein the mixer converts the MR RF signal from the RF coil array to an intermediate-frequency (IF) signal; and an electronic amplifier disposed in the coil housing, the electronic amplifier being electronically connected to the mixer and configured to amplify the IF signal from the mixer to an amplified IF signal.

2 . The apparatus of claim 1 , wherein the mixer and the electronic amplifier are packaged in a single integrated circuit chip disposed in the coil housing.

3 . The apparatus of claim 1 , further comprising:
an analog-to-digital converter electronically connected to the electronic amplifier.

4 . The apparatus of claim 3 , wherein the analog-to-digital converter converts analog signals from the electronic amplifier to digital signals.

5 . The apparatus of claim 4 , further comprising: a serializer electronically connected to the analog-to-digital converter and configured to receive the digital signals from the analog-to-digital converter.

6 . The apparatus of claim 5 , wherein the serializer is electronically connected to a low-frequency cable and outputs a low-frequency signal to a magnetic resonance scanner.

7 . The apparatus of claim 1 , further comprising:
a combiner connected to the electronic amplifier; an analog-to-digital converter (ADC) electronically connected to the combiner; and a digital converter electronically connected to the ADC.

8 . The apparatus of claim 7 , further comprising:
a serializer electronically connected to the digital converter and configured to generate serialized data to be sent to an MR system.

9 . A magnetic resonance imaging (MRI) system, comprising:
a magnet system configured to generate a static magnetic field about at least a region of interest (ROI) of a subject arranged in the MRI system; at least one gradient coil configured to establish at least one magnetic gradient field with respect to the static magnetic field; a radio frequency (RF) system configured to deliver at least one excitation pulse to the subject; at least one computer system configured to reconstruct images of the subject from image data acquired by the MRI system, wherein the magnet system, gradient coil, and RF system are arranged in a first location defining a magnet room and the at least one computer system is located in a second location that is magnetically distinct from the magnet room; and a receiver comprising:
an RF coil array comprising at least one coil configured to receive magnetic resonance (MR) RF signal excited by the at least one excitation pulse in the ROI;
a mixer electrically coupled to the RF coil array and arranged in the magnet room, wherein the mixer converts the MR RF signal from the RF coil array to an intermediate-frequency (IF) signal; and
an electronic amplifier electrically connected to the mixer to amplify the IF signal from the mixer to an amplified IF signal and arranged in the magnet room.

10 . The MRI system of claim 9 , wherein the mixer and the electronic amplifier are packaged in a common integrated circuit chip disposed in the coil housing.

11 . The MRI system of claim 10 , wherein the receiver further comprises an analog-to-digital converter electronically connected to the electronic amplifier and arranged in the magnet room.

12 . The MRI system of claim 11 , wherein the analog-to-digital converter converts analog signals from the electronic amplifier to digital signals.

13 . The MRI system of claim 12 , wherein the receiver further comprises a serializer electronically connected to the analog-to-digital converter and configured to receive the digital signal from the analog-to-digital converter.

14 . The MRI system of claim 13 , wherein the serializer is electronically connected to a low-frequency cable and outputs a low-frequency signal to a data acquisition server in the MRI system.

15 . The MRI system of claim 9 , wherein the receiver further comprises:
a combiner connected to the electronic amplifier; an analog-to-digital converter (ADC) electronically connected to the combiner; and a digital converter electronically connected to the ADC.

16 . The MRI system of claim 15 , wherein the receiver further comprises:
a serializer electronically connected to the digital converter and configured to generate serialized data to be sent to a data acquisition server in the MRI system.

17 . An integrated circuit chip in a MR receiver, comprising:
a semiconductor layer; a mixer disposed in the semiconductor layer and configured to receive magnetic resonance (MR) RF signals from a coil array and converts the MR RF signals to intermediate-frequency (IF) signals; and an electronic amplifier disposed in the semiconductor layer, the electronic amplifier being electronically connected to the mixer and configured to amplify the IF signals from the mixer to amplified IF signals.

18 . The integrated circuit chip of claim 17 , further comprising:
a combiner disposed in the semiconductor layer, the combiner being connected to the electronic amplifier and configured to combine amplified signals from multiple electronic amplifiers; and an analog-to-digital converter (ADC) disposed in the semiconductor layer, the analog-to-digital converter being electronically connected to the combiner.

19 . The integrated circuit chip of claim 18 , further comprising:
a local oscillator (LO) divider electronically connected to the mixer and the ADC, wherein the LO divider takes a reference LO signal and divides the reference LO signal into a plurality of non-overlapping signals with interleaved phase.

20 . The integrated circuit chip of claim 18 , further comprising:
a digital converter disposed in the semiconductor layer, the digital converter being electronically connected to the ADC; and a serializer electronically connected to the digital converter and configured to generate serialized data to be sent to an MR system.

Assignees

• Univ Case Western Reserve

Inventors

• Twieg Michael
• Griswold Mark A
• Mandal Soumyajit

Classifications

• H03D7/165

  at least two frequency changers being located in different paths, e.g. in two paths with carriers in quadrature (combined with amplitude demodulation H03D1/2245, combined with angle demodulation H03D3/007; N-path filters H03H19/002) · CPC title

• H03D2200/0086

  Reduction or prevention of harmonic frequencies · CPC title

• G01R33/3415

  comprising arrays of sub-coils {, i.e. phased-array coils with flexible receiver channels} · CPC title

• H03D7/12 Primary

  by means of semiconductor devices having more than two electrodes (H03D7/14 - H03D7/22 take precedence) · CPC title

• G01R33/3607 Primary

  RF waveform generators, e.g. frequency generators, amplitude-, frequency- or phase modulators or shifters, pulse programmers, digital to analog converters for the RF signal, means for filtering or attenuating of the RF signal · CPC title