Transmit/receive switch

• US 20040266362A1
• Filed: 06/27/2003
• Published: 12/30/2004
• Est. Priority Date: 06/27/2003
• Status: Abandoned Application

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Charles Kelley, Douglas Arthur, Watkins, Ronald Dean
• Application Number:
  US10/609,799
• Publication Number:
  US 20040266362A1
• Time in Patent Office: Days
• US Class Current: 455/78
• CPC Class Codes: H04B 1/44 Transmit/receive switching

Abstract

A transmit/receive switch for a system operating over a range of frequencies is provided. The switch comprises a pair of quadrature hybrid circuits and a switching means for coupling the pair of circuits. When the switch is operating in a transmit mode, the hybrid circuits provide a low loss path between a transmitter. When the switch is operating in a receive mode, the hybrid circuits provide a high isolation from the RF coil to a pre-amplifier.

Claims

1. A transmit/receive switch for a system operating over a range of frequencies comprising:

a pair of quadrature hybrid circuits;

a switching means for coupling the pair of circuits;

wherein the hybrid circuits provide a low loss path between a transmitter and a radio frequency (RF) coil when the switch is operating in a transmit mode; and

the hybrid circuits provide a high isolation from the RF coil to a pre-amplifier when the switch is operating in a receive mode.

2. The transmit/receive switch of claim 1, wherein the switching means comprises shunt switches.

3. The transmit/receive switch of claim 1, wherein the switching means comprises series switches.

4. The transmit/receive switch of claim 1, comprising

a first port coupled to the transmitter;

a second port coupled to the RF coil; and

a third port coupled to a receiver channel.

5. The transmit/receive switch of claim 4, further comprising a fourth port coupled to impedance.

6. The transmit/receive switch of claim 1, wherein the quadrature hybrid circuit is selected from the group containing quasi-lumped circuits, branch line hybrids, broadband hybrid circuits and transformer coupled hybrid circuits.

7. The transmit/receive switch of claim 1, wherein the quadrature hybrid circuits are designed using elements selected from the group containing lumped elements, co-axial transmission lines, microstrips and waveguides.

8. The transmit/receive switch of claim 1, wherein the range of frequency ranges from about 5 MHz to 1000 MHz.

9. The transmit/receive switch of claim 1, wherein the transmit/receive switch is adapted to operate in a high magnetic field.

10. The transmit/receive switch of claim 9, wherein the high magnetic field is greater than 2 Tesla.

11. The transmit/receive switch of claim 10, wherein the high magnetic field is 7 Tesla.

12. The transmit/receive switch of claim 1 where the switch is adapted to be used in a high field magnetic resonance imaging (MRI) system.

13. The transmit/receive switch of claim 12, wherein the switch is designed using non-magnetic components.

14. A method for implementing a transmit and receive switching capability for a system operating comprising:

providing a switching means for coupling a pair of quadrature hybrid circuits, wherein the hybrid circuits provide a low loss path between a transmitter and a radio frequency (RF) coil when the switch is operating in a transmit mode; and

wherein the hybrid circuits provide a high isolation from the RF coil to a pre-amplifier when the switch is operating in a receive mode.

15. The method of claim 14, wherein the switching means is operated for frequency ranges from about 5 MHz to 1000 MHz.

16. The method of claim 14, wherein the switching means is adapted to operate in a high magnetic field.

17. The method of claim 16, wherein the high magnetic field is greater than 2 Tesla.

18. The method of claim 17, wherein the high magnetic field is 7 Tesla.

19. The method of claim 14 where the switching means is adapted to be used in a high field magnetic resonance imaging (MRI) system.

20. The method of claim 19, wherein the switching means is designed using non-magnetic components.