Adaptive matching network

• US 8,942,657 B2
• Filed: 05/08/2013
• Issued: 01/27/2015
• Est. Priority Date: 01/14/2006
• Status: Active Grant

• Current Assignee: NXP USA, Inc. (NXP Semiconductors NV)
• Original Assignee: Blackberry Limited
• Inventors: McKinzie, William E. III, Bachmann, Heinz, Mendolia, Greg
• Primary Examiner(s): Tran, Pablo
• Application Number:
  US13/889,806
• Publication Number:
  US 20130241664A1
• Time in Patent Office: 629 Days
• Field of Search: 455/248.1, 455/67.14, 455/67.13, 455/77, 455/87, 455/178.1, 455/73, 455/83, 455/13.3, 455/67.11, 455/169.1, 455/182.3, 455/192.3, 455/197.2, 455/340.C, 455121-125, 455/129, 333133-134, 333/175, 333/178
• US Class Current: 455/248.1
• CPC Class Codes: H03H 7/38 Impedance-matching networks
• CPC Class Codes: H03H 7/40 Automatic matching of load impedance to source impedance
• 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 system that incorporates teachings of the present disclosure can include, for example, an apparatus having a matching network adapted to reduce a magnitude of a signal reflection at a port of the matching network. The matching network can have one or more controllable variable reactive elements. A controller can be adapted to determine reflection coefficient information from incident and reflected waves sampled at the port of the matching network, and follow at least one cycle of a coarse tune process for generating one or more control signals to tune one or more reactances of the one or more controllable variable reactive elements. Additional embodiments are disclosed.

Claims

1. An apparatus, comprising:

a matching network that reduces a magnitude of a signal reflection at a port of the matching network responsive to one or more control signals supplied by a circuit,

wherein the matching network comprises one or more variable reactive elements, and

wherein the circuit determines reflection coefficient information from incident and reflected waves sampled at the port of the matching network, and initiates a tuning process by generating the one or more control signals to adjust one or more reactances of the one or more variable reactive elements.

2. The apparatus of claim 1, wherein a directional coupler samples the incident and reflected waves at the port.

3. The apparatus of claim 1, wherein the circuit determines the reflection coefficient information from samples provided by an analog to digital converter.

4. The apparatus of claim 1, wherein a look-up table is used to perform the tuning process.

5. The apparatus of claim 1, wherein the circuit determines new reflection coefficient information to initiate a subsequent tuning process.

6. The apparatus of claim 5, wherein the tuning process is initially a coarse tuning process, and wherein when the new reflection coefficient information has achieved a desired value, the tuning process transitions to a fine tuning process that adjusts the one or more reactances of the one or more variable reactive elements by applying iterative adjustments to the one or more control signals.

7. The apparatus of claim 6, wherein the fine tuning process compensates for variations in manufacturing tolerances or temperature variations of the matching network.

8. The apparatus of claim 1, wherein the one or more control signals generated by the tuning process are supplied to a plurality of digital to analog converters that control buffers that generate the one or more control signals.

9. The apparatus of claim 8, wherein the one or more control signals comprise one or more direct current signals.

10. The apparatus of claim 1, wherein the reflection coefficient information is determined from samples supplied to the circuit by at least one analog to digital converter, and wherein the one or more control signals are directed to a plurality of digital to analog converters that generate the one or more control signals.

11. The apparatus of claim 1, wherein the one or more variable reactive elements comprise at least one of:

one or more reactive elements controlled by one or more semiconductor devices, wherein the one or more semiconductor devices are controlled by the one or more control signals;

one or more reactive elements controlled by one or more micro-electro-mechanical systems devices, wherein the one or more micro-electro-mechanical systems devices are controlled by the one or more control signals;

or

one or more reactive elements each having a controllable reactance, wherein the reactance of each of the one or more reactive elements is controlled by one of the one or more control signals.

12. The apparatus of claim 1, wherein the one or more control signals are one of one or more digital signals, one or more analog signals, or combinations thereof.

13. A machine-readable storage medium, comprising instructions, wherein responsive to executing the instructions, a circuit performs operations comprising:

determining a reflection coefficient from incident and reflected waves detected at a port of a variable reactive network; and

tuning one or more variable reactive elements of the variable reactive network with one or more control signals determined according to the reflection coefficient.

14. The storage medium of claim 13, wherein tuning is performed according to a look-up table that provides values for generating the one or more control signals.

15. The storage medium of claim 13, wherein the operations further comprise:

determining a new reflection coefficient from an additional sampling at the port of the variable reactive network;

detecting that the new reflection coefficient achieves a desired measurement; and

tuning the one or more variable reactive elements using iterative adjustments to the one or more control signals according to the new reflection coefficient.

16. The storage medium of claim 13, wherein the operations further comprise sampling a signal from the port of the variable reactive network, wherein the reflection coefficient is determined according to the signal.

17. The storage medium of claim 13, wherein the one or more variable reactive elements comprise at least one of:

one or more reactive elements controlled by one or more semiconductor devices, wherein the one or more semiconductor devices are controlled by the one or more control signals;

one or more reactive elements controlled by one or more micro-electro-mechanical systems devices, wherein the one or more micro-electro-mechanical systems devices are controlled by the one or more control signals;

or

one or more reactive elements each having a controllable reactance, wherein the reactance of each of the one or more reactive elements is controlled by one of the one or more control signals.

18. A method, comprising:

determining a reflection coefficient from a signal sampled at a port;

determining at least one control signal from the reflection coefficient; and

tuning a variable reactive network with the at least one control signal, wherein the variable reactive network has a variable reactance adjusted by the at least one control signal.

19. The method of claim 18, wherein tuning is performed according to a coarse tuning process.

20. The method of claim 18, wherein tuning is performed according to a fine tuning process.

21. The method of claim 18, wherein the variable reactive network comprises at least one of:

one or more reactive elements controlled by one or more semiconductor devices, wherein the one or more semiconductor devices are controlled by the one or more control signals;

one or more reactive elements controlled by one or more micro-electro-mechanical systems devices, wherein the one or more micro-electro-mechanical systems devices are controlled by the one or more control signals;

or

one or more reactive elements each having a controllable reactance, wherein the reactance of each of the one or more reactive elements is controlled by one of the one or more control signals.