Method and system for operating a communications device that communicates via inductive coupling

• US 10,390,200 B2
• Filed: 12/19/2016
• Issued: 08/20/2019
• Est. Priority Date: 12/19/2016
• Status: Active Grant

• Current Assignee: NXP B.V. (NXP Semiconductors NV)
• Original Assignee: NXP B.V. (NXP Semiconductors NV)
• Inventors: Hueber, Gernot, Bruckbauer, Johannes, Merlin, Erich
• Primary Examiner(s): Bilodeau, David
• Application Number:
  US15/383,406
• Publication Number:
  US 20180176712A1
• Time in Patent Office: 974 Days
• Field of Search: None
• CPC Class Codes: H04B 17/318 Received signal strength
• CPC Class Codes: H04B 5/24 Inductive coupling
• CPC Class Codes: H04B 5/72 for local intradevice communication
• CPC Class Codes: H04B 5/77 for interrogation
• 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

Embodiments of methods and systems for operating a communications device that communicates via inductive coupling are described. In an embodiment, a method for operating a communications device that communicates via inductive coupling involves obtaining transmission output power information related to the communications device and measuring a detuning condition based on the transmission output power information. Other embodiments are also described.

Claims

1. A method for operating a communications device that communicates via inductive coupling, the method comprising:

obtaining transmission output power information related to the communications device;

obtaining a received signal strength indicator (RSSI) at the communications device; and

measuring a detuning condition by estimating a field strength of inductive coupling based on a combination of the transmission output power information and the RSSI, and by generating a ratio between a transmitter impedance when a corresponding communications device is in close proximity to the communications device and a nominal transmitter impedance when there is not a corresponding communications device in close proximity to the communications device.

2. The method of claim 1, wherein the transmission output power information comprises a transmitter current and a transmitter voltage within the communications device.

3. The method of claim 1, further comprising adjusting a transmitter configuration of the communications device in response to the detuning condition.

4. The method of claim 1, wherein obtaining the transmission output power information comprises obtaining a transmitter current and a transmitter voltage within the communications device from a supply regulator of the communications device.

5. The method of claim 1, wherein obtaining the transmission output power information comprises obtaining a transmitter current and a transmitter voltage within the communications device from a transmitter driver of the communications device.

6. The method of claim 1, wherein measuring the detuning condition further comprises generating a ratio between a receiver gain when a corresponding communications device is in close proximity to the communications device and a nominal receiver gain when there is not a corresponding communications device in close proximity to the communications device.

7. The method of claim 1, wherein measuring the detuning condition comprises measuring the detuning condition before transmitting a message to a corresponding communications device.

8. A communications device that communicates via inductive coupling, the communications device comprising:

a system parameter sensor unit configured to obtain transmission output power information related to the communications device and to obtain a received signal strength indicator (RSSI) at the communications device; and

a detuning condition measurement unit configured to measure a detuning condition by estimating a field strength of inductive coupling based on a combination of the transmission output power information and the RSSI, and the detuning condition measurement unit configured to generate a ratio between a transmitter impedance when a corresponding communications device is in close proximity to the communications device and a nominal transmitter impedance when there is not a corresponding communications device in close proximity to the communications device.

9. The communications device of claim 8, wherein the transmission output power information comprises a transmitter current and a transmitter voltage within the communications device.

10. The communications device of claim 8, further comprising a control unit configured to adjust a transmitter configuration of the communications device in response to the detuning condition.

11. The communications device of claim 8, wherein the system parameter sensor unit is configured to obtain a transmitter current and a transmitter voltage within the communications device from a supply regulator of the communications device.

12. The communications device of claim 8, wherein the system parameter sensor unit is configured to obtain a transmitter current and a transmitter voltage within the communications device from a transmitter driver of the communications device.

13. The communications device of claim 8, wherein the detuning condition measurement unit is configured to generate a ratio between a receiver gain when a corresponding communications device is in close proximity to the communications device and a nominal receiver gain when there is not a corresponding communications device in close proximity to the communications device.

14. The communications device of claim 8, wherein the detuning condition measurement unit is configured to measure the detuning condition based on the transmission output power information before transmitting a message to a corresponding communications device.

16. The method of claim 14, wherein measuring the detuning condition based on the transmission output power information of the communications device further comprises generating a ratio between a receiver gain when a corresponding communications device is in close proximity to the communications device and a nominal receiver gain when there is not a corresponding communications device in close proximity to the communications device.

15. A method for operating a communications device that communicates via inductive coupling, the method comprising:

obtaining transmission output power information related to the communications device; and

measuring a detuning condition based on the transmission output power information, wherein measuring the detuning condition based on the transmission output power information of the communications device comprises generating a ratio between a transmitter impedance when a corresponding communications device is in close proximity to the communications device and a nominal transmitter impedance when there is not a corresponding communications device in close proximity to the communications device.