METHOD AND APPARATUS FOR REDUCING NFC MULTI-PROTOCOL POLLING DURATION AND POWER CONSUMPTION

• US 20130005242A1
• Filed: 06/28/2011
• Published: 01/03/2013
• Est. Priority Date: 06/28/2011
• Status: Active Grant

• Current Assignee: NXP USA, Inc. (NXP Semiconductors NV)
• Original Assignee: Broadcom Corporation (Broadcom, Inc.)
• Inventors: ROYSTON, Philip Stewart
• Granted Patent: US 8,824,961 B2
• Time in Patent Office: Days
• US Class Current: 455/41.1
• CPC Class Codes: G06K 7/10138 the step consisting of determining the type of record carrier, e.g. to determine if the record carrier is an RFID tag of the long or short range type, or to determine the preferred communication protocol of the RFID tag
• CPC Class Codes: G06K 7/10237 the reader and the record carrier being capable of selectively switching between reader and record carrier appearance, e.g. in near field communication [NFC] devices where the NFC device may function as an RFID reader or as an RFID tag
• CPC Class Codes: G06K 7/10297 arrangements for handling protocols designed for non-contact record carriers such as RFIDs NFCs, e.g. ISO/IEC 14443 and 18092 cryptographic protocols H04L9/00; network security protocols H04L63/00; real-time communication protocols in data switching networks H04L65/00; network protocols for data switching network services H04L67/00

Abstract

A method and apparatus are disclosed for polling for near field communications (NFC) devices by checking for multiple protocols. A NFC device polls for devices by first maintaining an unmodulated carrier field active for a specific period of time. The NFC device then polls using a first modulation and waits for a response. If there is no response, and without again maintaining another unmodulated carrier field for a specific period of time, the NFC device polls using a second modulation that is greater than the first modulation and waits again for a response.

Claims

1. A method for detecting a Near Field Communication (NFC) device, comprising:

polling with a first polling command using a first modulation on a carrier field after a first guard time;

maintaining the carrier field without modulation for a first reply period to detect a response to the first polling command from the NFC device;

polling, without waiting for a second guard time, with a second polling command using a second modulation on the carrier field that is greater than the first modulation; and

maintaining the carrier field without modulation for a second reply period to detect the response to the second polling command from the NFC device.

2. The method of claim 1, further comprising:

activating the carrier field;

maintaining the carrier field without modulation during the first guard time; and

communicating with the NFC device if the response is received from the NFC device while waiting during the first reply period.

3. The method of claim 2, further comprising:

polling with a third polling command using a third modulation on the carrier field;

maintaining the carrier field without modulation for a third reply period to detect the response to the third polling command from the NFC device; and

communicating with the NFC device if the response is received from the NFC device while waiting during the third reply period,

wherein the third polling command is pursuant to a proprietary standard.

4. The method of claim 2, wherein the first polling command is directed to a Type B NFC technology tag, and wherein the second polling command is directed to a Type A NFC technology tag.

5. The method of claim 2, wherein the first polling command is directed to a Type F NFC technology tag, and wherein the second polling command is directed to a Type A NFC technology tag.

6. The method of claim 4, wherein the first modulation is a 10% amplitude modulation, and wherein the second modulation is a 100% amplitude modulation.

7. The method of claim 5, wherein the first modulation is less than 100% amplitude modulation, and wherein the second modulation is a 100% amplitude modulation.

8. A method for detecting a Near Field Communication (NFC) device comprising:

receiving a first polling command using a first modulation on a carrier field after a first guard time from a NFC reader;

replying to the first polling command from the NFC reader during a first reply period if the NFC device is configured for the first modulation;

receiving a second polling command using a second modulation on the carrier field that is greater than the first modulation, without a second guard time from the NFC reader; and

replying to the second polling command from the NFC reader during a second reply period if the NFC device is configured for the second modulation.

9. The method of claim 8, further comprising:

deriving power from the carrier field without modulation during the first guard time.

10. The method of claim 9, further comprising:

receiving a third polling command using a third modulation on the carrier field;

replying to the third polling command from the NFC reader during a third reply period if the NFC device is configured for the third modulation,

wherein the third polling command is pursuant to a proprietary standard.

11. The method of claim 9, wherein the first polling command is directed to a Type B NFC technology tag, and wherein the second polling command is directed to a Type A NFC technology tag.

12. The method of claim 9, wherein the first polling command is directed to a Type F NFC technology tag, and wherein the second polling command is directed to a Type A NFC technology tag.

13. The method of claim 11, wherein the first modulation is a 10% amplitude modulation, and wherein the second modulation is a 100% amplitude modulation.

14. The method of claim 12, wherein the first modulation is less than 100% amplitude modulation, and wherein the second modulation is a 100% amplitude modulation.

15. An apparatus for detecting a Near Field Communication (NFC) device comprising:

a first NFC device configured to;

poll with a first polling command using a first modulation on a carrier field after a first guard time;

maintain the carrier field without modulation for a first reply period to detect a response to the first polling command from the NFC device;

poll, without waiting for a second guard time, with a second polling command using a second modulation on the carrier field that is greater than the first modulation; and

maintain the carrier field without modulation for a second reply period to detect the response to the second polling command from the NFC device.

16. The apparatus of claim 15, wherein the first device is further configured to:

activate the carrier field;

maintain the carrier field without modulation during the first guard time; and

communicate with the NFC device if the response is received from the NFC device while waiting during the first reply period.

17. The apparatus of claim 16, wherein the first polling command is directed to a Type B NFC technology tag, and wherein the second polling command is directed to a Type A NFC technology tag.

18. The apparatus device of claim 15, wherein the first polling command is directed to a Type F NFC technology tag, and wherein the second polling command is directed to a Type A NFC technology tag.

19. The apparatus of claim 17, wherein the first modulation is a 10% amplitude modulation, and wherein the second modulation is a 100% amplitude modulation.

20. The apparatus of claim 18, wherein the first modulation is less than 100% amplitude modulation, and wherein the second modulation is a 100% amplitude modulation.