Wireless device

• US 10,355,791 B1
• Filed: 04/10/2018
• Issued: 07/16/2019
• Est. Priority Date: 04/10/2018
• Status: Active Grant

• Current Assignee: NXP B.V. (NXP Semiconductors NV)
• Original Assignee: NXP B.V. (NXP Semiconductors NV)
• Inventors: Kerselaers, Anthony, Gomme, Liesbeth
• Primary Examiner(s): Trinh, Sonny
• Application Number:
  US15/949,231
• Time in Patent Office: 462 Days
• Field of Search: 455423, 455 6711, 4552261, 4554522, 455135, 4551613
• 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
• CPC Class Codes: H04B 17/12 of transmit antennas, e.g. of the amplitude or phase
• CPC Class Codes: H04B 17/309 Measuring or estimating channel quality parameters
• CPC Class Codes: H04B 5/24 Inductive coupling
• CPC Class Codes: H04W 24/08 Testing, supervising or monitoring using real traffic
• CPC Class Codes: H04W 52/26 using transmission rate or quality of service QoS [Quality of Service]

Abstract

One example discloses a circuit for varying a quality-factor of a wireless device: wherein the wireless device includes an antenna tuning circuit and a communications signal interface; the circuit including, a quality-factor circuit having a feedback circuit; wherein the feedback circuit is configured to be coupled between the antenna tuning circuit and the communications signal interface; wherein the quality-factor circuit is configured to measure an antenna system bandwidth of the wireless device; and wherein the feedback circuit is configured to apply positive feedback to the antenna tuning circuit if the measured bandwidth is greater than a maximum communication signal bandwidth.

Claims

1. A circuit for varying a quality-factor of a wireless device:

wherein the wireless device includes an antenna tuning circuit and a communications signal interface;

comprising, a quality-factor circuit having a feedback circuit;

wherein the feedback circuit is configured to be coupled between the antenna tuning circuit and the communications signal interface;

wherein the quality-factor circuit is configured to measure an antenna system bandwidth of the wireless device; and

wherein the feedback circuit is configured to apply positive feedback to the antenna tuning circuit if the measured bandwidth is greater than a maximum communication signal bandwidth.

2. The device of claim 1:

wherein the maximum bandwidth varies with a type of communication signal received by the wireless device.

3. The device of claim 2:

wherein the type of communication signal is at least one of;

an NFEI signal, or an RF signal.

4. The device of claim 2:

wherein the type of communication signal is an NFEMI signal.

5. The device of claim 2:

wherein the type of communication signal is an NFMI signal.

6. The device of claim 1:

wherein the feedback circuit is configured to increase the positive feedback if at least one of;

a decrease in signal strength, amplitude distortion, phase distortion, non-linear group delay, or an antenna system bandwidth increase, is detected at the communications signal interface.

7. The device of claim 1:

wherein the feedback circuit is configured to decrease the positive feedback if oscillation in the wireless device is detected.

8. The device of claim 1:

wherein the quality-factor circuit is configured to measure the antenna system bandwidth between subsequent communication signal receptions within the wireless device.

9. The device of claim 1:

wherein the feedback circuit is configured to identify a level for the positive feedback from a table containing a set of positive feedback levels corresponding to a set of measured antenna system bandwidths.

10. The device of claim 1:

wherein the feedback circuit is configured to go into a standby mode if the measured bandwidth is less than the maximum communication signal bandwidth.

11. The device of claim 1:

wherein the feedback circuit is configured to increase a resistance in the antenna tuning circuit if the measured bandwidth is less than a minimum communication signal bandwidth.

12. The device of claim 1, wherein the quality-factor circuit is configured to:

inject a set of test signals into the antenna tuning circuit;

measure a set of voltages generated by the antenna tuning circuit in response to the test signals; and

determine the antenna system bandwidth of the wireless device based on a comparison between the test signals and the measured voltages.

13. The device of claim 12:

wherein at least one of the test signals is at a center frequency of the communication signal.

14. The device of claim 13:

wherein at least two of the test signals are equally offset from the center frequency.

15. The device of claim 1:

further comprising the wireless device; and

wherein the positive feedback decreases the antenna system bandwidth and increases a quality-factor of the wireless device.

16. The device of claim 15:

wherein the wireless device is at least one of;

a wearable device, an earbud, a wristband, a smartwatch, or a sensor.

17. The device of claim 15:

wherein the wireless device is configured as a receiver.

18. The device of claim 1:

wherein the communications signal interface is configured to output a communications signal; and

wherein the positive feedback is configured to feed the communications signal back into the antenna tuning circuit.

19. An article of manufacture including at least one non-transitory, tangible machine readable storage medium containing executable machine instructions for adjusting a bandwidth of a wireless device, comprising:

wherein the wireless device includes an antenna tuning circuit and a communications signal interface;

wherein the article includes a quality-factor circuit having a feedback circuit;

wherein the feedback circuit is configured to be coupled between the antenna tuning circuit and the communications signal interface;

wherein the instructions include,

measuring an antenna system bandwidth of the wireless device; and

applying positive feedback to the antenna tuning circuit if the measured bandwidth is greater than a maximum communication signal bandwidth.

20. The article of claim 19, wherein the instructions further include:

increasing a resistance in the antenna tuning circuit if the measured bandwidth is less than a minimum communication signal bandwidth.