APPARATUS AND METHOD FOR CONTROLLING A TUNABLE MATCHING NETWORK IN A WIRELESS NETWORK

• US 20120051409A1
• Filed: 08/22/2011
• Published: 03/01/2012
• Est. Priority Date: 09/01/2010
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Brobston, Michael L., Zhu, Xu, Bui, Au Duy, Hutcheson, George Z.
• Granted Patent: US 8,712,348 B2
• Time in Patent Office: Days
• US Class Current: 375/222
• 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

An apparatus and method manage impedance values in a radio in a wireless network. The apparatus includes a tunable matching network (TMN) positioned on a path between a transceiver and an antenna. The TMN includes a plurality of immittance elements. A voltage standing wave ratio (VSWR) detector is configured to detect a ratio of a signal passing the VSWR detector and a signal reflected from the TMN. A control circuit is configured to identify an operating setting for the radio, set a number of the immittance elements based on the operating setting, monitor the ratio detected by the VSWR detector, and modify a setting of at least one of the immittance elements based on the ratio detected.

Claims

1. An apparatus for managing impedance values in a radio in a wireless network, the apparatus comprising:

a tunable matching network (TMN) positioned on a path between a transceiver and an antenna, the TMN comprising a plurality of immittance elements;

a voltage standing wave ratio (VSWR) detector configured to detect a ratio of a signal passing the VSWR detector and a signal reflected from the TMN; and

a control circuit configured to identify an operating setting for the radio, set a number of the immittance elements based on the operating setting, monitor the ratio detected by the VSWR detector, and modify a setting of at least one of the immittance elements based on the ratio detected.

2. The apparatus of claim 1 further comprising:

a front end module operably connected to the TMN and the transceiver, wherein the signal passing the VSWR detector is a signal from the front end module,

wherein the control circuit is configured to match a value of impedance for the antenna with a value of impedance for the front end module by modifying settings of at least one of the plurality of immittance elements in the TMN.

3. The apparatus of claim 1 further comprising:

a power amplifier in the transceiver, the power amplifier operably connected to the TMN, wherein the signal passing the VSWR detector is a signal from the power amplifier,

wherein the control circuit is configured to modify settings of at least one of the plurality of immittance elements in the TMN to achieve a value for the ratio that improves a performance parameter of the power amplifier.

4. The apparatus of claim 3, wherein the performance parameter of the power amplifier is at least one of a power added efficiency parameter, a gain parameter, a linearity parameter, a modulation quality parameter, and an output power parameter.

5. The apparatus of claim 1 further comprising:

a front end module operably connected to the TMN and the transceiver, wherein the signal passing the VSWR detector is a signal from the front end module, wherein the ratio is an antenna ratio, and wherein the control circuit is configured to match a value of impedance for the antenna with a value of impedance for the front end module by modifying settings of the plurality of immittance elements in the TMN

a second TMN operably connected to the front end module and a power amplifier in the transceiver, the second TMN comprising a second plurality of immittance elements;

a second VSWR detector configured to detect a power amplifier ratio of a signal from the power amplifier and a signal reflected from the second TMN; and

a second control circuit configured to set a number of the second plurality of immittance elements based on the operating setting, monitor the power amplifier ratio detected by the second VSWR detector, and modify settings of the plurality of immittance elements in the TMN to achieve a value for the power amplifier ratio that improves a performance parameter of the power amplifier based on the power amplifier ratio detected by the second VSWR detector.

6. The apparatus of claim 1 further comprising:

a modem configured to operate at an operating channel of frequencies, wherein the control circuit is configured to identify the operating setting for the radio by identifying the operating channel of frequencies from the modem.

7. The apparatus of claim 1 further comprising:

a storage device configured to store data regarding performance parameters of the radio, wherein the control circuit is configured to identify the operating setting for the radio from the data stored in the storage device, wherein the operating setting of the radio is based on at least one of an operating channel of frequencies used by the radio, an operating mode of the radio, and parameters of components in the radio.

8. The apparatus of claim 1, wherein the radio is in a mobile station, wherein the operating setting for the radio is a preset setting based on known parameters of the mobile station, and wherein the control circuit is configured to modify the setting of at least one of the immittance elements based on changes in an operating environment of the mobile station.

9. The apparatus of claim 1 further comprising:

a storage device configured to store a table including settings for the TMN based on the ratio detected by the VSWR detector,

wherein the control circuit is further configured to modify the setting of at least one of the immittance elements based on the ratio detected and the settings in the table.

10. The apparatus of claim 1, wherein the ratio detected by the VSWR detector is output from the VSWR detector in a signal representing one of a magnitude of the signal reflected from the TMN, a phase of the signal reflected from the TMN, and both the magnitude and the phase of the signal reflected from the TMN.

11. A method for managing impedance values in a radio in a wireless network, the method comprising:

identifying an operating setting for the radio;

setting a number of a plurality of immittance elements in a tunable matching network (TMN) positioned on a path between a transceiver and an antenna based on the operating setting;

detecting, by a detector, a ratio of a signal passing the detector and a signal reflected from the TMN; and

modifying a setting of at least one of the immittance elements based on the ratio detected.

12. The method of claim 11, wherein modifying the setting of at least one of the immittance elements based on the ratio detected comprises:

matching a value of impedance for the antenna with a value of impedance for a front end module, wherein the front end module is operably connected to the TMN and the transceiver and wherein the signal passing the detector is a signal from the front end module.

13. The method of claim 11, wherein modifying the setting of at least one of the immittance elements based on the ratio detected comprises:

modifying settings of at least one of the plurality of immittance elements in the TMN to achieve a value for the ratio that improves a performance parameter of a power amplifier in the transceiver, wherein the power amplifier is operably connected to the TMN and wherein the signal passing the detector is a signal from the power amplifier.

14. The method of claim 11, wherein the TMN is positioned between the antenna and a front end module, wherein the signal passing the detector is a signal from the front end module, and further comprising:

setting a number of a second plurality of immittance elements in a second TMN positioned on a path between a power amplifier and a front end module based on the operating setting;

detecting, by a second detector, a power amplifier ratio of a signal from the power amplifier and a signal reflected from the second TMN; and

modifying settings of the plurality of immittance elements in the TMN to achieve a value for the power amplifier ratio that improves a performance parameter of the power amplifier based on the power amplifier ratio detected by the second detector.

15. The method of claim 11, wherein identifying the operating setting for the radio comprises:

identifying an operating channel of frequencies from a modem in the transceiver, wherein the modem configured to operate at the operating channel of frequencies.

16. The method of claim 11, wherein identifying the operating setting for the radio comprises:

identifying the operating setting for the radio from a data regarding performance parameters of the radio stored in a storage device, wherein the operating setting of the radio is based on at least one of an operating band of frequencies used by the radio, an operating channel used by the radio, an operating mode of the radio, and parameters of components in the radio.

17. The method of claim 11, wherein identifying the operating setting for the radio comprises:

identifying a transmit operating frequency (TX) and a receive operating frequency (RX) for the radio, wherein the operating setting includes a group of control variables for the TMN, wherein the group of control variables are selected based on one of the TX, the RX, and a compromise for both TX and RX; and

wherein modifying the setting of at least one of the immittance elements based on the ratio detected comprises;

modifying settings of the group of control variables.

18. A mobile station in a wireless network, the mobile station comprising:

an antenna;

a front end module;

a power amplifier;

a first tunable matching network (TMN) operably connected to the front end module and the antenna, the first TMN comprising a first plurality of immittance elements;

a first voltage standing wave ratio (VSWR) detector configured to detect an antenna ratio of a signal from the front end module and a signal reflected from the first TMN;

a second TMN operably connected to the front end module and the power amplifier, the second TMN comprising a second plurality of immittance elements;

a second VSWR detector configured to detect a power amplifier ratio of a signal from the power amplifier and a signal reflected from the second TMN; and

a control circuit configured to identify an operating setting for mobile station, set a number of the first plurality of immittance elements and a number of the second plurality of immittance elements based on the operating setting, modify settings of at least one of the first plurality of immittance elements in the TMN based on the antenna ratio detected by the first VSWR detector to match a value of impedance for the antenna with a value of impedance for the front end module, and modify settings of the plurality of immittance elements in the TMN to achieve a value for the power amplifier ratio that improves a performance parameter of the power amplifier based on the power amplifier ratio detected by the second VSWR detector.

19. The mobile station of claim 18 further comprising:

a modem configured to operate at an operating band and channel of frequencies, wherein the control circuit is configured to identify the operating setting for the mobile station by identifying the operating channel of frequencies from the modem.

20. The mobile station of claim 18 further comprising:

a storage device configured to store data regarding performance parameters of the mobile station,

wherein the control circuit is configured to identify the operating setting for the mobile station from the data stored in the storage device, wherein the operating setting of the mobile station is based on at least one of an operating band of frequencies used by the mobile station, an operating channel used by the radio, an operating mode of the mobile station, and parameters of components in the mobile station.