Granted Patent B2

US 7,529,526 · App. 10/868,123 · Granted May 5, 2009

Abstract

Claims (35)

1. An apparatus for transmitting and receiving wireless signals, the apparatus comprising:

an RF transmit path including a power amplifier configured to produce an amplified transmit signal at a power level;

an RF receive path;

an antenna switch operably connected to said RF transmit path, said RF receiver path, an antenna, and a switch driver, the antenna switch configured to switch the antenna between the RF receive path and the RF transmit path based on a control signal from said switch driver;

a control line connected between said antenna switch and a switch driver;

a power amplifier detector connected to said control line, the power amplifier detector configured to receive a leakage signal leaking from the antenna switch through said transmit control line, and measure a power level of the leakage signal, which is indicative of the power level of the amplified transmit signal when the antenna switch is connected to the RF transmit path; and

a power amplifier controller connected to the power amplifier detector and the power amplifier, the power amplifier controller configured to adjust the power level of the power amplifier based on the leakage signal detected by the power amplifier detector.

2. The apparatus as recited in claim 1 , wherein the apparatus is a wireless device.

3. The apparatus of claim 1 , wherein said antenna switch is configured to receive a DC control signal from said switch driver to connect either said RF transmit path or said RF receive path to said antenna.

4. The apparatus of claim 3 , wherein said control line comprises a capacitor, said switch driver being connected between said capacitor and said antenna switch and said detector is connected on the other side of said capacitor.

5. The apparatus of claim 4 , wherein said control line comprises a capacitor and a resistor, wherein said power amplifier detector is connected between said capacitor and said resistor and said switch driver is connector between said capacitor and said antenna switch.

6. The apparatus of claim 4 , wherein said capacitor is configured to block control signals from said power amplifier driver from reaching said detector but conducts said leakage signal.

7. An apparatus, comprising:

an RF transmit path including a power amplifier, configured to amplify a transmit signal to a particular power level;

an RF receive path;

an antenna switch operably connected to said transmit path, said receiver path, an antenna, and a switch driver, the antenna switch configured to switch the antenna between the RF receive path and the RF transmit path;

said switch driver connected to the antenna switch via a control line;

a power amplifier detector connected to the control line, the power amplifier detector configured to receive a leakage signal from the antenna switch when it is connected to the RF transmit path to detect the particular power level of the transmit signal, wherein said leakage signal is indicative of the power level of the transmit signal detected on the control line; and

a power amplifier controller connected to the power amplifier detector and the power amplifier, the power amplifier controller configured to adjust the power level of transmit signal produced by the power amplifier based on the leakage signal detected by the power amplifier detector.

8. The apparatus as recited in claim 7 , wherein the apparatus is a wireless device.

9. The apparatus as recited in claim 7 , wherein the apparatus is a transmit module of a wireless device.

10. The apparatus of claim 7 , wherein said antenna switch is configured to receive a DC control signal from said switch driver to connect either said RF transmit path or said RF receive path to said antenna.

11. The apparatus of claim 10 , wherein said control line comprises a capacitor, said switch driver being connected between said capacitor and said antenna switch and said detector is connected on the other side of said capacitor.

12. The apparatus of claim 11 , wherein said control line comprises a capacitor and a resistor, wherein said power amplifier detector is connected between said capacitor and said resistor and said switch driver is connector between said capacitor and said antenna switch.

13. The apparatus of claim 11 , wherein said capacitor is configured to block control signals from said power amplifier driver from reaching said detector but conducts said leakage signal.

14. A method, comprising:

detecting a leakage signal from a control line connector to an antenna switch operably connected to an RF transmit path, an RF receive path and an antenna, wherein the leakage signal is indicative of a portion of an power level of a transmit signal produced by a radio frequency (RF) power amplifier on the transmit path when said antenna is connected to said RF transmit path; and

measuring a power level of said leakage signal at a power amplifier detector wherein the power amplifier detector is not on said RF receive path; and

at a power amplifier controller connected to said power amplifier detector and the power amplifier, adjusting the output power level of the power amplifier based on the detected leakage signal.

15. The method as recited in claim 14 , wherein said power amplifier detector is connected to a port on the antenna switch.

16. The method as recited in claim 14 , wherein said power amplifier detector is connected to a control line between a driver for the antenna switch and the antenna switch.

17. The method of claim 14 , wherein said antenna switch receives a DC control signal from said switch driver to connect either said RF transmit path or said RF receive path to said antenna.

18. The method of claim 17 , wherein said control line comprises a capacitor, said switch driver being connected between said capacitor and said antenna switch and said detector is connected on the other side of said capacitor such that said leakage signal is coupled across said capacitor before being detected.

19. The method of claim 18 , wherein said control line comprises a capacitor and a resistor, wherein said power amplifier detector is connected between said capacitor and said resistor and said switch driver is connector between said capacitor and said antenna switch.

20. The method of claim 18 , wherein said capacitor is configured to block control signals from said power amplifier driver from reaching said detector but conducts said leakage signal.

Assignments (10)