MAGNETIC RESONANCE SCANNER WITH WIRELESS TRANSMISSION OF SIGNALS

• US 20100117646A1
• Filed: 11/05/2009
• Published: 05/13/2010
• Est. Priority Date: 11/12/2008
• Status: Active Grant

• Current Assignee: Siemens Healthineers AG (Siemens AG)
• Original Assignee: Siemens AG
• Inventors: Vester, Markus, Hulbert, Anthony Peter
• Granted Patent: US 8,258,788 B2
• Time in Patent Office: Days
• US Class Current: 324/309
• CPC Class Codes: G01R 33/3415 comprising arrays of sub-coils , i.e. phased-array coils with flexible receiver channels
• CPC Class Codes: G01R 33/3692 involving signal transmission without using electrically conductive connections, e.g. wireless communication or optical communication of the MR signal or an auxiliary signal other than the MR signal

Abstract

A wireless magnetic resonance imaging scanner has one or more local coils, a microwave antenna array, and a local oscillator, and an upconverter. The local oscillator signal from the local oscillator is transmitted from the microwave antenna array to illuminate the local coils. The local coils generate magnetic resonance signals at a first frequency and the magnetic resonance signals at the first frequency are upconverted in the upconverter to microwave frequencies. The local oscillator operates at a frequency within an unlicensed band, chosen such that desired sidebands for reception of the upconverted local coil magnetic resonance signals fall outside the unlicensed band.

Claims

1. A wireless magnetic resonance imaging data acquisition device, comprising:

local coils and gradient coils operable to obtain magnetic resonance data from a subject, a microwave antenna array, a local oscillator, and an upconverter;

said local oscillator supplying a local oscillator signal from the microwave antenna array to illuminate the local coils;

said local coils generating said magnetic resonance signals at a first frequency, and said upconverter upconverting said magnetic resonance signals at said first frequency to microwave frequencies; and

said local oscillator operating at a frequency within an unlicensed spectrum band selected that desired sidebands for reception of the upconverted local coil magnetic resonance signals fall outside of said unlicensed spectrum band.

2. A device as claimed in claim 1 wherein only sideband among said upper and lower sidebands of said local coil magnetic resonance signals is desired.

3. A device as claimed in claim 2 wherein the desired sidebands fall outside of a spillover region of said unlicensed spectrum band.

4. A device as claimed in claim 2 wherein said local oscillator supplies a local oscillator frequency for upper sideband reception that is greater than a resultant of a maximum frequency of the unlicensed spectrum band with the Larmor frequency subtracted therefrom, plus the Larmor frequency-required half bandwidth, plus a maximum frequency spillover outside of the unlicensed spectrum band.

5. A device as claimed in claim 2 wherein the local oscillator supplies a local oscillator frequency for lower sideband reception that is less than a resultant of the minimum frequency of the unlicensed spectrum band plus the Larmor frequency, with the Larmor frequency-required half bandwidth subtracted therefrom and with a maximum frequency spillover outside of the unlicensed spectrum band subtracted therefrom.

6. A device as claimed in claim 1 wherein said local oscillator supplies a local oscillator frequency for reception of both sidebands that falls between a local oscillator frequency for upper sideband reception and a local oscillator frequency for lower sideband reception.

7. A device as claimed in claim 1 wherein a maximum unlicensed spectrum band bandwidth, in which said device is operated, is less than twice the Larmor frequency with the Larmor frequency-required bandwidth subtracted therefrom, and with twice a maximum frequency spillover outside of the unlicensed spectrum band subtracted therefrom.

8. A device as claimed in claim 1 wherein said local oscillator emits said local oscillator frequency in the Industrial, Scientific and Medical (ISM) frequency band.

9. A device as claimed in claim 8 wherein said local oscillator emits said local oscillator frequency in a 2.4 GHz ISM band.

10. A device as claimed in claim 1 wherein said microwave antenna array and said local oscillator are mounted in a bore tube of said device, and said local coils are mounted at least partially within a central bore with said bore tube.

11. A wireless magnetic resonance imaging data acquisition device, comprising:

a magnetic resonance data acquisition unit comprising local coils and gradient coils operable to obtain magnetic resonance data from a subject, a microwave antenna array, a local oscillator, and an upconverter;

said local oscillator supplying a local oscillator signal from the microwave antenna array to operate the local coils;

said local coils generating said magnetic resonance signals at a first frequency, and said upconverter upconverting said magnetic resonance signals at said first frequency to microwave frequencies; and

said local oscillator operating at a frequency within an unlicensed spectrum band selected that desired sidebands for reception of the upconverted local coil magnetic resonance signals fall outside of said unlicensed spectrum band.