System and method for adjusting variable(s) related to near field communications antenna for mobile devices to ensure antenna operation within a defined operating range

• US 10,841,773 B2
• Filed: 10/23/2019
• Issued: 11/17/2020
• Est. Priority Date: 11/13/2014
• Status: Active Grant

• Current Assignee: Stripe, Inc.
• Original Assignee: BBPOS Limited
• Inventors: Tsai, Hwai Sian, Choi, Peter, Lo, Chi Wah
• Primary Examiner(s): Gonzales, April G
• Application Number:
  US16/661,816
• Publication Number:
  US 20200059773A1
• Time in Patent Office: 391 Days
• Field of Search: 455 6714, 455 411
• CPC Class Codes: H04B 5/263 Multiple coils at either side
• CPC Class Codes: H04B 5/72 for local intradevice communication
• CPC Class Codes: H04W 4/80 Services using short range communication, e.g. near-field communication [NFC], radio-frequency identification [RFID] or low energy communication

Abstract

A system for an antenna for near field communications (NFC), said antenna comprising a primary loop with a primary current to produce a magnetic field; one or more secondary loops with one or more secondary currents; wherein by adjusting one or more variables associated with said one or more secondary loops, said magnetic field is modified to ensure antenna operation within a defined operating range.

Claims

1. An antenna for near field communications (NFC), the antenna comprising:

a primary loop driven with a primary current to produce a first magnetic field with an associated first magnetic field distribution within an operating volume of the antenna,

such that the associated first magnetic field distribution is stronger in a center of the primary loop relative to an edge of the primary loop;

a secondary loop disposed within the center of the primary loop and driven with a secondary current to produce a second magnetic field, wherein;

the second magnetic field combines with the first magnetic field to produce an overall magnetic field with an associated overall magnetic field distribution within the operating volume of the antenna, and

the combining comprising either enhancing or suppressing the first magnetic field in the center of the primary loop, and

the enhancing or suppressing changes the associated overall magnetic field distribution; and

a processing device executing instructions associated with an adjustment module coupled to the primary loop and the secondary loop,

the adjustment module performing one or more adjustments to the secondary current while the primary current is read,

the one or more adjustments related to at least one of the executed instructions, and

the one or more adjustments comprising adjusting an amplitude and phase of the secondary current relative to the primary current to;

remove imbalances in the associated overall magnetic field distribution, and

ensure the overall magnetic field has a field strength within a range over the operating volume of the antenna.

2. The antenna of claim 1, wherein:

at least some part of the adjustment module is implemented in software.

3. The antenna of claim 2, wherein:

the processing device is located on a mobile device;

the antenna is located on the mobile device; and

the at least some part of the adjustment module is implemented as an application running on the mobile device.

4. A method for adjusting an overall magnetic field of a near field communications (NFC) antenna for a mobile device, the method comprising:

executing, by a processing device, instructions associated with an adjustment module coupled to a primary loop and a secondary loop of the antenna,

reading, by the adjustment module, a primary current in the primary loop,

wherein the primary loop has a first magnetic field with an associated first magnetic field distribution within an operating volume of the antenna,

such that the associated first magnetic field distribution is stronger in a center of the primary loop relative to an edge of the primary loop, and

wherein the secondary loop is disposed within the center of the primary loop and has a secondary current to produce a second magnetic field,

the second magnetic field combining with the first magnetic field to produce an overall magnetic field within the operating volume of the antenna,

the overall magnetic field having an associated overall magnetic field distribution,

the combining comprising either enhancing or suppressing the first magnetic field in the center of the primary loop, and

the enhancing or suppressing changes the associated overall magnetic field distribution; and

performing, by the adjustment module, one or more adjustments to the secondary current while the primary current is read,

the one or more adjustments related to at least one of the instructions executed by the processing device,

the one or more adjustments comprising adjusting an amplitude and phase of the secondary current relative to the primary current to;

remove imbalances in the associated overall magnetic field distribution, and

ensure the associated overall magnetic field distribution has a field strength within a range over the operating volume of the antenna.

5. The method of claim 4, wherein:

the one or more adjustments are performed over a period of time.

6. The method of claim 4, wherein:

the one or more adjustments are performed based on at least one machine learning algorithm.

7. The method of claim 4, wherein:

the one or more adjustments are based on at least one of simulation or measurement.

8. The method of claim 4, wherein:

the one or more adjustments are performed to meet a shape requirement of the operating volume.

9. A system for a near field communications (NFC) antenna having a primary loop and a secondary loop comprising:

an adjustment module coupled to the primary loop and the secondary loop,

the primary loop having a primary current to produce a first magnetic field with an associated first magnetic field distribution within an operating volume of the antenna,

such that the associated first magnetic field distribution is stronger in a center of the primary loop relative to an edge of the primary loop, and

the secondary loop disposed within the center of the primary loop and driven with a secondary current to produce a second magnetic field,

wherein the second magnetic field combines with the first magnetic field to produce an overall magnetic field with an associated overall magnetic field distribution within the operating volume of the antenna, and

the combining comprising either enhancing or suppressing the first magnetic field in the center of the primary loop, and

the enhancing or suppressing changes the associated overall magnetic field distribution; and

a processing device executing instructions associated with the adjustment module,

the adjustment module varying the secondary current while reading the primary current,

the varying related to at least one of the instructions executed by the processing device,

the varying comprising adjusting an amplitude and phase of the secondary current relative to the primary current to;

remove imbalances in the associated overall magnetic field distribution, and

ensure the overall magnetic field has a field strength within a range over the operating volume of the antenna.

10. The system of claim 9, wherein:

at least some part of the adjustment module is implemented in software.

11. The system of claim 10, wherein:

the processing device is located on a mobile device;

the antenna is located on the mobile device; and

the at least some part of the adjustment module is implemented as an application running on the mobile device.

12. A method for an antenna for near field communications (NFC), the method comprising:

providing a primary loop driven with a primary current to produce a first magnetic field with an associated first magnetic field distribution within an operating volume of the antenna,

such that the associated first magnetic field distribution is stronger in a center of the primary loop relative to an edge of the primary loop;

providing a secondary loop disposed within the center of the primary loop and driven with a secondary current to produce a second magnetic field, wherein;

the second magnetic field combines with the first magnetic field to produce an overall magnetic field with an associated overall magnetic field distribution within the operating volume of the antenna, and

the combining comprising either enhancing or suppressing the first magnetic field in the center of the primary loop, and

the enhancing or suppressing changes the associated overall magnetic field distribution; and

providing a processing device executing instructions associated with an adjustment module coupled to the primary loop and the secondary loop,

the adjustment module performing one or more adjustments to the secondary current while the primary current is read,

the one or more adjustments related to at least one of the executed instructions, and

the one or more adjustments comprising adjusting an amplitude and phase of the secondary current relative to the primary current to;

remove imbalances in the associated overall magnetic field distribution, and

ensure the overall magnetic field has a field strength within a range over the operating volume of the antenna.

13. The method of claim 12, wherein at least a portion of the adjustment module is implemented in software.

14. The method of claim 13, wherein:

the processing device is located on a mobile device;

the antenna is located on the mobile device; and

the at least a portion of the adjustment module is implemented as an application running on the mobile device.

15. The method of claim 12, wherein the one or more adjustments are performed over a period of time.

16. The method of claim 12, wherein the one or more adjustments are performed based on at least one machine learning algorithm.

17. The method of claim 16, wherein the one or more adjustments are performed using an offline stage and an online stage.

18. The method of claim 17, further comprising:

during the online stage,

capturing one or more measurements in real-time, and

performing the one or more adjustments; and

during the offline stage,

processing the captured one or more measurements to produce inputs to

the at least one machine learning algorithm, and refining, by the at least one machine learning algorithm, the one or more adjustments using the produced inputs.

19. The method of claim 12, wherein the one or more adjustments are based on at least one of simulation or measurement.

20. The method of claim 12, wherein the one or more adjustments are performed to meet a shape requirement of the operating volume.