Claims
- 1. An apparatus for providing a radio frequency output from a radio frequency drive to an antenna, said apparatus comprising:
a driver amplifier having an input connected to said radio frequency drive and an output; a first circuit path comprising an input connected to the output of the driver amplifier and an output connectable to said antenna; a second circuit path comprising an input connected to the driver amplifier, an output connectable to said antenna, and a power amplifier connected between the input and output of the second circuit path and comprising a bias lead; and a switch device having: a first state wherein the output of the first circuit path is connected to the antenna to provide a radio frequency output thereto, the output of the second circuit path is disconnected from said antenna, and the bias lead of the power amplifier is disconnected from a bias, and a second state wherein the output of the second circuit path is connected to the antenna to provide a radio frequency output thereto, the output of the first circuit path is disconnected from said antenna, and the bias lead of the power amplifier is connected to a bias.
- 2. The apparatus, as set forth in claim 1, wherein said first circuit path further comprises a first matching network.
- 3. The apparatus, as set forth in claim 1, wherein said second circuit path further comprises a second matching network.
- 4. The apparatus, as set forth in claim 1, wherein said first circuit path further comprises a first matching network and wherein said second circuit path further comprises a second matching network.
- 5. The apparatus, as set forth in claim 1, further comprising an RF detector.
- 6. The apparatus, as set forth in claim 5, further comprising a hysteresis circuit in communication with said RF detector for controlling operation of said switching means.
- 7. The apparatus, as set forth in claim 6, further comprising a second switch device coupled to said driver amplifier.
- 8. The apparatus, as set forth in claim 7, wherein said second switch device has a first state for coupling said driver amplifier to said power amplifier.
- 9. The apparatus, as set forth in claim 8, wherein said second switch device has a second state for coupling said power amplifier to said antenna.
- 10. An apparatus for providing a radio frequency output from a radio frequency drive to an antenna, said apparatus comprising:
a first circuit path comprising an input connectable to said radio frequency drive, an output connectable to said antenna, and a driver amplifier having a first bias lead; a second circuit path comprising an input connected to said radio frequency drive, an output connectable to said antenna, a second driver amplifier having a second bias lead, and a power amplifier having a third bias lead; and a switch device having: a first state wherein the output of the first circuit path is connected to the antenna to provide a radio frequency output thereto, the output of the second circuit path is disconnected from the antenna, a bias is connected to the first bias lead, and the second and third bias leads are disconnected from a bias, and a second state wherein the output of the second circuit path is connected to the antenna to provide a radio frequency output thereto, the second and third bias leads are connected to a bias, and the first bias lead is disconnected from a bias.
- 11. The apparatus, as set forth in claim 10, wherein said first circuit path further comprises a first matching network.
- 12. The apparatus, as set forth in claim 10, wherein said second circuit path further comprises a second matching network.
- 13. The apparatus, as set forth in claim 10, wherein said first circuit path further comprises a first matching network and wherein said second circuit path further comprises a second matching network.
- 14. The apparatus, as set forth in claim 10, further comprising an RF detector.
- 15. The apparatus, as set forth in claim 14, further comprising a hysteresis circuit in communication with said RF detector for controlling operation of said switching device.
- 16. A method of providing a radio frequency output from a radio frequency drive to an antenna, said method comprising the steps of:
providing a first path to an antenna; providing a second path to said antenna, said second path having a power amplifier; coupling said second path to said antenna in response to a high power request; and providing a first bias to said power amplifier when said second path is connected to said antenna.
- 17. The method of, as set forth in claim 16, further comprising a step of providing a driver amplifier in said first path.
- 18. The method of, as set forth in claim 17, further comprising a step of biasing said driver amplifier in said first path when said first path is coupled to said antenna.
- 19. The method of, as set forth in claim 16, further comprising a step of providing a driver amplifier in said second path.
- 20. The method of, as set forth in claim 19, further comprising a step of biasing said driver amplifier in said first path when said first path is coupled to said antenna.
Parent Case Info
[0001] The following application is a divisional of application Ser. No. 09/211,638 filed Dec. 15, 1998.
Divisions (1)
|
Number |
Date |
Country |
Parent |
09211638 |
Dec 1998 |
US |
Child |
09971480 |
Oct 2001 |
US |