USE OF RDS DATA TO SELECT MATCHING NETWORK

• US 20110058627A1
• Filed: 09/04/2009
• Published: 03/10/2011
• Est. Priority Date: 09/04/2009
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Fisher, Joseph Roi JR., Warren, Daniel Adam, Yang, James Tsung-Tai
• Granted Patent: US 8,948,310 B2
• Time in Patent Office: Days
• US Class Current: 375/316
• CPC Class Codes: H03H 7/38 Impedance-matching networks
• 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
• CPC Class Codes: H04B 1/18 Input circuits, e.g. for coupling to an antenna or a transmission line coupling networks between antennas or lines and receivers independent of the nature of the receiver H03H

Abstract

Devices and methods for dynamically selecting a matching network for an antenna are provided. In one example, an electronic device capable of selecting such a matching network may include an antenna, several selectable matching networks, a radio receiver, and matching network control circuitry. The radio receiver may couple to the antenna via one of the selectable matching networks to receive a radio signal with both an analog and digital component. The matching network control circuitry may select the matching network from among the several selectable matching networks based at least in part on a characteristic of the digital component of the radio signal.

Claims

1. An electronic device comprising:

an antenna;

a plurality of selectable matching networks;

a radio receiver coupled to the antenna via one of the plurality of selectable matching networks and capable of receiving a radio signal that includes an analog component and a digital component; and

matching network control circuitry capable of selecting the one of the plurality of selectable matching networks based at least in part on a characteristic associated with the digital component of the radio signal.

2. The electronic device of claim 1, wherein the antenna comprises a flexible conductor.

3. The electronic device of claim 1, wherein the antenna comprises a headset conductively coupled to the electronic device.

4. The electronic device of claim 1, wherein the plurality of selectable matching networks comprises a first matching network configured to match a profile of the antenna when the radio receiver is tuned to a first frequency band and a second matching network configured to match the profile of the antenna when the radio receiver is tuned to a second frequency band.

5. The electronic device of claim 1, wherein the radio receiver comprises circuitry capable of decoding the digital component of the radio signal.

6. The electronic device of claim 1, wherein the radio receiver comprises an FM radio receiver having a Radio Data System decoder or a Radio Broadcast Data System decoder, or a combination thereof.

7. The electronic device of claim 1, comprising a first switch configured to couple the antenna to the one of the plurality of selectable matching networks and a second switch configured to couple the one of the plurality of selectable matching networks to the radio receiver, wherein the first switch and the second switch are configured to couple to the one of the plurality of selectable matching networks based on a control signal from the matching network control circuitry.

8. An electronic device comprising:

a flexible antenna having a variable network profile;

a plurality of selectable matching networks;

a radio receiver coupled to the flexible antenna via one of the plurality of selectable matching networks and capable of receiving and decoding a broadcast radio signal that includes a digital signal in the Radio Data System or the Radio Broadcast Data System format, or a combination thereof;

data processing circuitry capable of determining a characteristic of the digital signal; and

matching network control circuitry capable of selecting the one of the plurality of selectable matching networks based at least in part on the characteristic of the digital signal.

9. The electronic device of claim 8, wherein the variable network profile of the flexible antenna is capable of varying depending on a physical configuration of the flexible antenna.

10. The electronic device of claim 8, wherein the matching network control circuitry is capable of selecting the one of the plurality of selectable matching networks based at least in part on the characteristic of the digital signal, wherein the characteristic of the digital signal comprises a locking speed of the digital signal;

a completeness of the digital signal;

a block error rate of the digital signal;

or a confidence of the digital signal;

or any combination thereof.

11. The electronic device of claim 8, wherein the matching network control circuitry is capable of selecting the one of the plurality of selectable matching networks, upon initialization of the radio receiver, by selecting an initial matching network of the plurality of selectable matching networks, evaluating the characteristics of the digital signal, and maintaining the selection of the initial matching network when the characteristics of the digital signal exceed a quality threshold and selecting another of the plurality of selectable matching networks when the characteristics of the digital signal do not exceed the quality threshold.

12. The electronic device of claim 8, wherein the matching network control circuitry is capable of selecting the one of the plurality of selectable matching networks, upon initialization of the radio receiver, by selecting a first matching network of the plurality of selectable matching networks, evaluating the characteristics of the digital signal while the first matching network is selected, selecting a second matching network of the plurality of selectable matching networks, evaluating the characteristics of the digital signal while the second matching network is selected, and selecting between the first matching network and the second matching network based at least in part on the characteristics of the digital signal evaluated while the first matching network was selected and while the second matching network was selected.

13. A method comprising:

receiving a radio broadcast signal from an antenna into a radio receiver via one of a plurality of selectable matching networks;

decoding an analog audio signal and a digital signal from the radio broadcast signal using the radio receiver;

evaluating a signal quality of the digital signal using the radio receiver; and

selecting another one of the plurality of selectable matching networks when the signal quality of the digital signal falls beneath a threshold using matching network control circuitry.

14. The method of claim 13, wherein the signal quality of the digital signal is evaluated based at least in part on a locking speed of the digital signal;

a completeness of the digital signal;

a block error rate of the digital signal;

or a confidence of the digital signal;

or any combination thereof.

15. The method of claim 13, wherein the signal quality of the digital signal is evaluated based at least in part by applying a discrete value to a signal characteristic of the digital signal, and wherein the other one of the plurality of selectable matching networks is selected when the discrete value falls beneath the threshold.

16. The method of claim 13, comprising evaluating a signal quality of the analog audio signal or of the radio broadcast signal, wherein the other one of the plurality of selectable matching networks is selected when the signal quality of the analog audio signal or of the radio broadcast signal falls beneath a threshold.

17. The method of claim 13, wherein the other one of the plurality of selectable matching networks is selected when the signal quality of the digital signal falls beneath the threshold, wherein the threshold is lower when the digital signal indicates that the analog audio signal comprises spoken audio than when the digital signal indicates that the analog audio signal comprises music.

18. An electronic device comprising:

a headphone jack configured to connect to a wired headset;

a radio receiver configured to decode an audio signal and a non-audio signal from a broadcast radio signal;

matching network circuitry electrically disposed between the headphone jack and the radio receiver and configured to selectably function as one of a plurality of matching networks between the wired headset and the radio receiver, such that the radio receiver is capable of receiving the broadcast radio signal when the wired headset is connected to the headphone jack;

matching network control circuitry configured to supply a control signal to the matching network circuitry to cause the matching network circuitry to function as the one of the plurality of matching networks; and

data processing circuitry configured to control the matching network control circuitry based at least in part on a quality of the non-audio signal.

19. The electronic device of claim 18, wherein the plurality of matching networks comprises a first matching network configured to transmit the broadcast radio signal when the broadcast radio signal is in a first radio frequency band and a second matching network configured to transmit the broadcast radio signal when the broadcast radio signal is in a second radio frequency band.

20. The electronic device of claim 18, wherein the matching network circuitry comprises a first switch configured to electrically couple the headphone jack to one of the plurality of matching networks and a second switch configured to electrically couple the one of the plurality of matching networks to the radio receiver, wherein the control signal is configured to cause the first switch and the second switch to connect to the one of the plurality of matching networks.

21. The electronic device of claim 18, wherein the matching network control circuitry comprises common matching network circuitry coupled to one or more switches, wherein the one or more switches are coupled to a plurality of matching network elements, wherein the matching network control circuitry is configured to function as the one of the plurality of matching networks when a corresponding one of the plurality of matching network elements is coupled to the common matching network circuitry, and wherein the control signal is configured to cause the one or more switches to couple the one of the plurality of matching network elements to the common matching network circuitry.

22. The electronic device of claim 18, wherein the data processing circuitry is configured to control the matching network control circuitry based at least in part on a quality of the audio signal.

23. The electronic device of claim 22, wherein the data processing circuitry is configured to control the matching network control circuitry based at least in part on the quality of the audio signal, wherein the quality of the audio signal is determined by evaluating a received signal strength indicator of the broadcast radio signal;

a signal-to-noise ratio of the broadcast radio signal;

or the presence of multipath characteristics in the broadcast radio signal;

or any combination thereof.

24. A method comprising:

receiving a broadcast radio signal from an antenna into a radio receiver via one of a plurality of selectable matching networks;

decoding an analog audio signal and a digital signal from the radio broadcast signal using the radio receiver;

selecting the one of the plurality of selectable matching networks from among the plurality of selectable matching networks based at least in part on a quality of the digital signal using matching network control circuitry; and

storing data relating to a context of use and the one of the plurality of selectable matching networks into volatile or nonvolatile memory.

25. The method of claim 24, wherein storing the data relating to the context of use comprises storing data relating to a frequency of the broadcast radio signal;

a location determined by location-sensing circuitry;

an orientation determined by one or more accelerometers;

or a global unique identifier associated with the antenna;

or any combination thereof.

26. The method of claim 24, comprising storing data relating to the quality of the digital signal when data relating to the context of use and the one of the plurality of selectable matching networks are stored.

27. The method of claim 24, comprising initializing the radio receiver after the data relating to the context of use the one of the plurality of selectable matching networks has been stored, evaluating a new context of use, and selecting the one of the plurality of selectable matching networks or another of the plurality of selectable matching networks using the matching network control circuitry based at least in part on a comparison between the new context of use and the stored context of use.