MRI radio frequency receiver comprising digital down converter with connector that passes analog signal being contained within radio frequency receiver coil unit

Patent metadata

Field	Value
Publication number	US-9784805-B2
Application number	US-66533608-A
Country	US
Kind code	B2
Filing date	Jun 16, 2008
Priority date	Jun 19, 2007
Publication date	Oct 10, 2017
Grant date	Oct 10, 2017

Abstract

The invention relates to a nuclear magnetic resonance imaging radio frequency-receiver ( 112; 216; 308; 404 ), the receiver ( 112; 216; 308; 404 ) being adapted to receive analog signals from at least one radio frequency receiver coil unit ( 106; 200; 202; 300; 400; 402 ), the radio frequency receiver ( 112; 216; 308; 404 ) comprising: an analog-digital converter ( 118; 226 ) to convert the analog pre-amplified magnetic resonance signal into a digital signal, means ( 120; 230 ) for digital down converting the digital signal and a first communication interface ( 130; 252 ) adapted for transmitting the down converted digital signal via a communication link (e.g. wireless, optical or wire-bound).

First claim

The invention claimed is:

1. A nuclear magnetic resonance (NMR) imaging radio frequency receiver, which is integrated into a radio frequency receiver coil unit defining a unitary structure, the unitary structure further containing a radio frequency receive coil and a coil element conditioner as part of a magnetic resonance imaging apparatus, the radio frequency receiver itself comprising:
an analogue-digital converter configured for converting an analogue magnetic resonance signal, received from the radio frequency receive coil through the coil element conditioner, into a digital signal;
a digital down converter configured for down converting the digital signal in order to reduce a data rate of the digital signal;
a first communication interface configured for transmitting the down converted digital signal via a communication link, wherein a connection for passing the analogue magnetic resonance signal from the radio frequency receive coil to the analogue-digital converter is contained inside the radio frequency receiver coil unit; and
a local clock voltage controlled oscillator configured for providing a short term stable clock that drives the analogue-digital converter.

2. The NMR imaging radio frequency receiver of claim 1 , wherein an analogue chain from the radio frequency receive coil to the analogue-digital converter has a length less than about 0.4 meter.

3. The NMR imaging radio frequency receiver of claim 1 , wherein the local clock voltage controlled oscillator is synchronizable by a pilot tone signal, the pilot tone signal being generated by a pilot tone transmit coil of the magnetic resonance imaging apparatus.

4. The NMR imaging radio frequency receiver of claim 1 , further comprising an encoder/compressor configured for at least one of encoding and compressing the down converted digital signal.

5. The NMR imaging radio frequency receiver of claim 1 , further comprising:
an analogue-digital converter local clock generator controlled by the local clock voltage controlled oscillator, enabling the analogue-digital converter local clock generator being configured to provide multiple frequencies to the analogue-digital converter when performing MRI at multiple magnetic fields of multiple nuclei.

6. The NMR imaging radio frequency receiver of claim 1 , further comprising a merge unit configured to combine the down converted digital signal with multiple digitized magnetic resonance signals and control and status signals for controlling the receiver, the multiple digitized magnetic resonance signals originating from multiple antenna elements of the receiver coil unit.

7. The NMR imaging radio frequency receiver of claim 1 , further comprising an electronic testing circuit configured for examining electronic components of the radio frequency receiver using a test coil, said test coil being included in the radio frequency receiver coil unit.

8. The NMR imaging radio frequency receiver of claim 1 , further comprising a spike detection unit configured detecting and removing spikes in the down converted digital signal.

9. The NMR imaging radio frequency receiver of claim 1 , wherein the first communication interface is configured for providing the down converted digital signal via the communication link by wireless radio frequency transmission.

10. A radio frequency (RF) interface structure configured for a magnetic resonance imaging system, the RF interface structure comprising:
at least one NMR imaging radio frequency receiver according to claim 1 ;
at least one second communication interface configured for communication with the first communication interface of the radio frequency receiver;
a merge unit configured to combine multiple signals communicated over multiple second communication interfaces to or from multiple radio frequency receiver coil units; and
a radio frequency scan control unit configured for controlling the radio frequency receiver.

11. The NMR imaging radio frequency receiver of claim 1 , wherein the voltage controlled oscillator comprises a voltage controlled crystal oscillator.

12. The NMR imaging radio frequency receiver of claim 1 , wherein the local clock voltage controlled oscillator is synchronizable by a system clock.

13. The NMR imaging radio frequency receiver of claim 1 , wherein the first communication interface is-configured for providing the down converted digital signal via the communication link by optical transmission.

14. The NMR imaging radio frequency receiver of claim 1 , wherein the first communication interface is configured for providing the down converted digital signal via the communication link using a wired transmission.

15. A magnetic resonance imaging system, comprising:
a main magnet configured for generating a main magnetic field;
magnetic field gradient coils configured for selectively generating magnetic field gradients that are to be superimposed onto the main magnetic field;
a radio frequency receiver coil unit defining a unitary structure containing:
a radio frequency receive coil configured for receiving analogue radio frequency signals responsive to an applied radio frequency pulse sequence that has been applied to the magnetic field, a coil element conditioner connected to the radio frequency receive coil that processes the analogue radio frequency signals, and a radio frequency receiver coupled to the coil element conditioner that receives the processed analogue radio frequency signals, wherein the radio frequency receiver coil, the coil element conditioner and the radio frequency receiver are integrated into the unitary structure, and wherein the radio frequency receiver comprises:
an analogue-digital converter configured to convert an analogue magnetic resonance signal, received from the radio frequency receive coil via an analogue chain, into a digital signal;
a digital down converter configured to down convert the digital signal in order to reduce a data rate of the digital signal;
a local clock voltage controlled oscillator configured to provide a low jitter clock that drives the analogue-digital converter; and
a first communication interface configured to transmit the down converted digital signal via a communication link, wherein connection for passing the analogue magnetic resonance signal from the radio frequency receive coil to the analogue-digital converter is contained inside the radio frequency receiver coil unit;

a second communication interface configured for communication with the first communication interface via the communication link; and
a control and data acquisition system configured for communicating with the radio frequency receiver using the second communication interface.

16. The magnetic resonance imaging system of claim 10 , further comprising:
a control and data acquisition system configured to generate at least one of pulse sequences and control commands in order to control an RF interface structure, including the radio frequency receiver.

17. The magnetic resonance imaging system of claim 15 , wherein the analogue chain from the radio frequency receive coil to the analogue-digital converter has a length less than about 0.4 meter.

18. A method of processing a radio frequency signal received by a radio frequency receiver, which is integrated into a radio frequency receiver coil unit defining a unitary structure, the unitary structure further containing a radio frequency receive coil, a coil element conditioner and a local clock voltage controlled oscillator, as part of a magnetic resonance imaging apparatus, the method comprising:
receiving an anal

Assignees

• Saes Marc Paul
• Van Den Brink Johan Samuel
• Van Liere Filips
• Penterman Roel
• Kurt Ralph
• Peeters Emiel
• Broer Dirk Jan
• Van Bruggen Michel Paul Barbara
• Van Zon Hans
• Fuderer Miha
• Koninklijke Philips Nv

Inventors

• Saes Marc Paul
• Van Den Brink Johan Samuel
• Van Liere Filips
• Penterman Roel
• Kurt Ralph
• Peeters Emiel
• Broer Dirk Jan
• Van Bruggen Michel Paul Barbara
• Van Zon Hans
• Fuderer Miha

Classifications

• G01R33/3621

  NMR receivers or demodulators, e.g. preamplifiers, means for frequency modulation of the MR signal using a digital down converter, means for analog to digital conversion [ADC] or for filtering or processing of the MR signal such as bandpass filtering, resampling, decimation or interpolation · CPC title

• G01R33/3692

  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 · CPC title

• G01R33/341 Primary

  comprising surface coils · CPC title

• G01R33/3415

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