Tuning circuitry in a communications device

• US 7,747,228 B2
• Filed: 03/31/2006
• Issued: 06/29/2010
• Est. Priority Date: 03/31/2006
• Status: Active Grant

• Current Assignee: Silicon Laboratories Incorporated
• Original Assignee: Silicon Laboratories Incorporated
• Inventors: Rafi, Aslamali A., Vancorenland, Peter J., Kasha, Dan B., Tuttle, George T., Kammula, Abhishek V.
• Primary Examiner(s): NGUYEN, SIMON
• Application Number:
  US11/394,451
• Publication Number:
  US 20070238423A1
• Time in Patent Office: 1,551 Days
• Field of Search: 455/91, 455120-1272, 455/129, 4551931-1933, 455/575.7, 343850-865
• US Class Current: 455/91
• CPC Class Codes: H04B 1/0458 Arrangements for matching and coupling between power amplifier and antenna or between amplifying stages matching circuits in general H03H

Abstract

A communications device is provided. The communications device includes a first antenna port coupled to a signal line, transmitter circuitry coupled to the signal line and configured to broadcast a radio frequency (RF) output signal across the first antenna port, tuning circuitry coupled to the signal line, and a controller configured to adjust a tuning of the tuning circuitry. The first antenna port, the transmitter circuitry, the tuning circuitry, and the controller are at least partially integrated on the same integrated circuit.

Claims

1. A communications device comprising:

a first antenna port coupled to a signal line;

a second antenna port

transmitter circuitry including first output stage circuitry coupled to the signal line and configured to broadcast a first radio frequency (RF) output signal across the first antenna port;

second output stage circuitry having an input coupled to the signal line and configured to broadcast a second RF output signal generated from the first RF output signal across the second antenna port;

tuning circuitry coupled to the signal line; and

a controller configured to provide a set of tuning signals to the tuning circuitry to adjust a tuning of the tuning circuitry and configured to provide a first control signal to the transmitter circuitry to adjust a first signal level of the first RF output signal on the signal line;

wherein the controller is configured to provide the set of tuning signals to adjust a capacitance and a resistance of the tuning circuitry, and wherein the first antenna port, the transmitter circuitry, the tuning circuitry, and the controller are at least partially integrated on the same integrated circuit.

2. The communications device of claim 1 wherein the controller is configured to provide the set of tuning signals to adjust the resistance of the tuning circuitry in response to the tuning circuitry forming at least a portion of a high Q circuit.

3. The communications device of claim 1 wherein the controller is configured to detect the signal level of the first RF output signal on the signal line.

4. The communications device of claim 1 wherein the tuning circuitry forms an LC filter with an inductance on the first antenna port.

5. The communications device of claim 4 further comprising:

an antenna coupled to one of the first antenna port and the second antenna port.

6. The communications device of claim 5 wherein the antenna forms the inductance.

7. The communications device of claim 5 further comprising:

an inductor coupled to the first antenna port that forms the inductance.

8. The communications device of claim 1 further comprising:

receiver circuitry coupled to the signal line.

9. The communications device of claim 1 wherein the controller is configured to provide a second control signal to the second output stage circuitry to adjust a second signal level of the second RF output signal.

10. The communications device of claim 1 wherein the tuning circuitry includes a plurality of cells controllable by the set of tuning signals, each of the plurality of cells including a respective resistive element coupled in series with a respective switch between the signal line and ground.

11. A method performed by a controller in a communications device, the method comprising:

providing a set of tuning signals to adjust a capacitance and a resistance of tuning circuitry coupled on a signal line between transmitter circuitry and an antenna port, the tuning circuitry forming an LC filter with an inductance on the antenna port;

detecting a signal level of a radio frequency (RF) output signal generated by the transmitter circuitry on the signal line subsequent to adjusting the tuning; and

providing a control signal to the transmitter circuitry to adjust the signal level of the RF output signal on the signal line subsequent to detecting the signal level.

12. The method of claim 11 further comprising:

providing a portion of the set of tuning signals to a plurality of cells that each include a respective resistive element coupled in series with a respective switch between the signal line and ground.

13. A communications system comprising:

an antenna;

a communications device including;

a first antenna port coupled to a signal line;

a second antenna port;

transmitter circuitry including first output stage circuitry coupled to the signal line and configured to broadcast a first radio frequency (RF) output signal across the first antenna port;

second output stage circuitry having an input coupled to the signal line and configured to broadcast a second RF output signal generated from the first RF output signal across the second antenna port;

tuning circuitry coupled to the signal line and forming an LC filter in combination with an inductance on the first antenna port; and

a controller configured to provide a set of tuning signals to the tuning circuitry to adjust a tuning of the tuning circuitry and configured to provide a first control signal to the transmitter circuitry to adjust a first signal level of the first RF output signal on the signal line;

wherein the controller is configured to provide the set of tuning signals to adjust a capacitance and a resistance of the tuning circuitry, and wherein the antenna port, the transmitter circuitry, the tuning circuitry, and the controller are at least partially integrated on the same integrated circuit; and

an input/output system configured to communicate with the communications device.

14. The communications system of claim 13 wherein the controller is configured to provide a second control signal to the second output stage circuitry to adjust a second signal level of the second RF output signal.

15. The communications system of claim 13 wherein the tuning circuitry includes a plurality of cells controllable by the set of tuning signals, each of the plurality of cells including a respective resistive element coupled in series with a respective switch between the signal line and ground.