Tuning a NFC antenna of a device

• US 9,936,337 B2
• Filed: 09/28/2015
• Issued: 04/03/2018
• Est. Priority Date: 05/23/2015
• Status: Active Grant

• Current Assignee: Block, Inc. (f/k/a Square, Inc.)
• Original Assignee: Square Inc (Block, Inc. (f/k/a Square, Inc.))
• Inventors: Lamba, Kartik, Wade, Jeremy, Maibach, Matthew H., Dorogusker, Jesse
• Primary Examiner(s): Sorowar, Golam
• Application Number:
  US14/868,247
• Publication Number:
  US 20160345123A1
• Time in Patent Office: 918 Days
• CPC Class Codes: G06K 7/10148 the step consisting of dynamically tuning the resonant circuit of the interrogation device that is emitting the interrogation signal, e.g. for impedance matching inside of the interrogation device for tuning related to loop aerials in general H01Q7/00
• CPC Class Codes: G06K 7/10336 the antenna being of the near field type, inductive coil
• CPC Class Codes: G06Q 20/3278 RFID or NFC payments by means of M-devices
• CPC Class Codes: H01Q 1/2216 used in interrogator/reader equipment
• CPC Class Codes: H01Q 7/00 Loop antennas with a substantially uniform current distribution around the loop and having a directional radiation pattern in a plane perpendicular to the plane of the loop
• CPC Class Codes: H04B 1/401 for selecting or indicating operating mode
• CPC Class Codes: H04B 5/24 Inductive coupling
• 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
• CPC Class Codes: H04W 52/0225 using monitoring of external events, e.g. the presence of a signal
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A NFC object reader'"'"'s NFC antenna system configured to dynamically change an element of the NFC antenna system to maintain the NFC antenna system'"'"'s antenna default resonant frequency. The NFC antenna system can be configured to include a tuning subsystem, integrated with sensors to trigger tuning of NFC antenna system'"'"'s antenna.

Claims

1. A near field communication (NFC) payment object reader that is portable and wireless, wherein the NFC payment object reader benefits from intermittent tuning, the NFC payment object reader comprising:

an accelerometer;

an NFC subsystem including an NFC antenna; and

a tuning subsystem configured to tune the NFC antenna, the tuning subsystem configured to receive an input from the accelerometer and based on the input from the accelerometer, initiate one of a plurality of tuning processes depending on whether the NFC payment object reader is stationary or in motion, the plurality of tuning processes including;

a first tuning process that is initiated in response to the tuning subsystem determining based on the input from the accelerometer that the NFC payment object reader is stationary, wherein the first tuning process results in a first tolerance for deviation from a desired frequency of the NFC antenna, and

a second tuning process that is initiated in response to the tuning subsystem determining based on the input from the accelerometer that the NFC payment object reader is in motion, wherein the second tuning process results in a second tolerance for deviation from the desired frequency of the NFC antenna that is different from the first tolerance for deviation from the desired frequency.

2. The NFC payment object reader of claim 1, wherein the first tuning process measures a first frequency transmitted by the NFC antenna and determines that the first frequency is not the desired frequency, wherein the first tuning process adjusts one or more variables to tune the NFC antenna to generate the desired frequency.

3. The NFC payment object reader of claim 1, wherein the second tolerance for deviation from the desired frequency is greater than the first tolerance for deviation from the desired frequency.

4. The NFC payment object reader of claim 1, wherein the second tuning process is configured to pause tuning of the NFC antenna.

5. A near field communication (NFC) payment object reader comprising:

an accelerometer;

an NFC antenna subsystem including an NFC antenna; and

a tuning subsystem configured to tune the NFC antenna subsystem, the tuning subsystem configured to receive an input from the accelerometer, the tuning subsystem configured to use different tuning processes depending on whether the NFC payment object reader is stationary or in motion, the different tuning processes including a first tuning process that is initiated in response to the tuning subsystem determining based on the input from the accelerometer that the NFC payment object reader is stationary, wherein the first tuning process corresponds to a first tolerance for deviation from a desired frequency of the NFC antenna, the different tuning processes including a second tuning process that is initiated in response to the tuning subsystem determining based on the input from the accelerometer that the NFC payment object reader is in motion, wherein the second tuning process corresponds to a second tolerance for deviation from the desired frequency of the NFC antenna, wherein the second tolerance for deviation from the desired frequency is different from the first tolerance for deviation from the desired frequency.

6. The NFC payment object reader of claim 5, wherein the input from the accelerometer indicates that the NFC payment object reader is stationary, and the tuning subsystem is configured to conduct the first tuning process based on the input from the accelerometer.

7. The NFC payment object reader of claim 5, wherein the input from the accelerometer indicates that the NFC payment object reader is in motion, and the tuning subsystem is configured to conduct the second tuning process based on the input from the accelerometer.

8. The NFC payment object reader of claim 5, wherein the input from the accelerometer indicates that the NFC payment object reader is stationary after having been in motion, and wherein the tuning subsystem is configured to tune the NFC subsystem in a manner that changes from the second tolerance for deviation from the desired frequency of the NFC antenna to the first tolerance for deviation from the desired frequency of the NFC antenna based on the input from the accelerometer.

9. The NFC payment object reader of claim 5, wherein the tuning subsystem is configured to terminate the first tuning process in response to a determination by the tuning subsystem that the NFC payment object reader is in motion based on the input from the accelerometer.

10. The NFC payment object reader of claim 5, wherein the tuning subsystem is configured to conduct the second tuning process in response to a determination by the tuning subsystem that the NFC payment object reader is in motion based on the input from the accelerometer.

11. The NFC payment object reader of claim 5, wherein the second tolerance for deviation from the desired frequency is greater than the first tolerance for deviation from the desired frequency.

12. The NFC payment object reader of claim 5, wherein the second tuning process is configured to attempt to tune the NFC antenna subsystem more frequently than the first tuning process.

13. The NFC payment object reader of claim 5, wherein the second tuning process utilizes a lower power than the first tuning process.

14. A method comprising:

receiving an accelerometer output of an accelerometer of a payment object reader into a tuning algorithm that controls tuning of a near field communication (NFC) antenna of the payment object reader;

determining whether the payment object reader is in motion based on the accelerometer output; and

adjusting the tuning algorithm to use one of a plurality of tuning processes depending on whether the NFC payment object reader is stationary or in motion, wherein the plurality of tuning processes include a first tuning process that is initiated in response to determining based on the accelerometer output from the accelerometer that the NFC payment object reader is stationary, wherein the first tuning process corresponds to a first tolerance for deviation from a desired frequency of the NFC antenna, wherein the plurality of tuning processes include a second tuning process that is initiated in response to determining based on the accelerometer output from the accelerometer that the NFC payment object reader is in motion, wherein the second tuning process corresponds to a second tolerance for deviation from the desired frequency of the NFC antenna, wherein the second tolerance for deviation from the desired frequency that is different from the first tolerance for deviation from the desired frequency.

15. The method of claim 14, further comprising:

determining that a first frequency of an NFC antenna is not within the second tolerance for deviation from the desired frequency; and

adjusting one or more variable capacitors using the tuning algorithm to tune the NFC antenna to generate a second frequency that is within the second tolerance for deviation from the desired frequency.

16. The method of claim 14, wherein the second tolerance for deviation from the desired frequency is greater than the first tolerance for deviation from the desired frequency.

17. The method of claim 14, wherein adjusting the tuning algorithm includes pausing tuning of the NFC antenna.

18. The method of claim 14, wherein adjusting the tuning algorithm includes decreasing an interval between attempts to tune the NFC antenna in accordance with the accelerometer output.

19. The method of claim 14, further comprising:

receiving a second accelerometer output of the accelerometer into the tuning algorithm;

determining that the payment object reader has stopped moving from a state of motion based on the accelerometer output and the second accelerometer output; and

adjusting the tuning algorithm from the second tuning process to the first tuning process in accordance with the determination that the payment object reader has stopped moving from the state of motion.