Methods and apparatus for improving the identification of multiple NFC-A devices

1. A method of wireless communications, comprising:

determining that a first device sensing response message includes one or more collisions among a plurality of remote near field communication (NFC) devices;

identifying a first remote NFC device of the plurality of remote NFC devices by performing collision resolution on the first device sensing response message;

transmitting a sleep request message to the first remote NFC device, which causes the first remote NFC device to transition to a sleep state that prohibits the first remote NFC device from responding to a first device sensing request message;

transmitting the first device sensing request message;

receiving a second device sensing response message that includes collisions among the plurality of remote NFC devices;

identifying a second remote NFC device of the plurality of remote NFC devices by performing collision resolution on the second device sensing response message;

storing the first device sensing response message in a first location in a storage structure, and the second device sensing response message in a second location in the storage structure;

receiving a collision free device sensing response message; and

determining collision free versions of the first and second device sensing response messages by analyzing the first device sensing response message in the first location and the second device sensing response message in the second location in the storage structure using the received collision free device sensing response message.

2. The method of claim 1 , further comprising:

transmitting a second device sensing request message as part of a technology detection process; and

receiving the first device sensing response message in response to the second device sensing request message.

3. The method of claim 1 , wherein the second device sensing response message overwrites the first device sensing response message.

4. The method of claim 1 , wherein each of the plurality of remote NFC devices is configured to use NFC-A radio frequency (RF) technology.

5. The method of claim 1 , wherein the first and second device sensing response messages are SENS_RES messages as defined in the NFC Forum Digital Protocol specification.

6. The method of claim 1 , wherein the second device sensing request message is a SENS_REQ message as defined in the NFC Forum Digital Protocol specification.

7. The method of claim 1 , wherein the sleep request message is a SLP_REQ message as defined in the NFC Forum Digital Protocol specification.

8. The method of claim 1 , wherein the plurality of remote NFC devices comprise at least one of a reader device, a writer device, a tag, a card, and a peer device.

9. The method of claim 1 , further comprising performing single device detection communications with each device that transmitted a device sensing response message to obtain a NFC device identifier (NFCID).

10. A non-transitory computer-readable medium, storing computer-executable code for wireless communications, comprising:

code for determining that a first device sensing response message includes one or more collisions among a plurality of remote near field communication (NFC) devices;

code for identifying a first remote NFC device of the plurality of remote NFC devices by performing collision resolution on the first device sensing response message;

code for transmitting a sleep request message to the first remote NFC device, which causes the first remote NFC device to transition to a sleep state that prohibits the first remote NFC device from responding to a first device sensing request message;

code for transmitting the first device sensing request message;

code for receiving a second device sensing response message that includes collisions among the plurality of remote NFC devices;

code for identifying a second remote NFC device of the plurality of remote NFC devices by performing collision resolution on the second device sensing response message;

code for storing the first device sensing response message in a first location in a storage structure, and the second device sensing response message in a second location in the storage structure;

code for receiving a collision free device sensing response message; and

code for determining collision free versions of the first and second device sensing response messages by analyzing the first device sensing response message in the first location and the second device sensing response message in the second location in the storage structure using the received collision free device sensing response message.

11. The non-transitory computer-readable medium of claim 10 , further comprising:

code for transmitting a second device sensing request message as part of a technology detection process; and

code for receiving the first device sensing response message in response to the second device sensing request message.

12. The non-transitory computer-readable medium of claim 10 , wherein the second device sensing response message overwrites the first device sensing response message.

13. The non-transitory computer-readable medium of claim 10 , wherein each of the plurality of remote NFC devices is configured to use NFC-A radio frequency (RF) technology.

14. The non-transitory computer-readable medium of claim 10 , wherein the first and second device sensing response messages are SENS_RES messages as defined in the NFC Forum Digital Protocol specification.

15. The non-transitory computer-readable medium of claim 10 , wherein the second device sensing request message is a SENS_REQ message as defined in the NFC Forum Digital Protocol specification.

16. The non-transitory computer-readable medium of claim 10 , wherein the sleep request message is a SLP_REQ message as defined in the NFC Forum Digital Protocol specification.

17. The non-transitory computer-readable medium of claim 10 , wherein the plurality of remote NFC devices comprise at least one of a reader device, a writer device, a tag, a card, and a peer device.

18. The non-transitory computer-readable medium of claim 10 , wherein the non-transitory computer-readable medium further comprises code for performing single device detection communications with each device that transmitted a device sensing response message to obtain a NFC device identifier (NFCID).

19. An apparatus for communications, comprising:

means for determining that a first device sensing response message includes one or more collisions among a plurality of remote near field communication (NFC) devices;

means for identifying a first remote NFC device of the plurality of remote NFC devices by performing collision resolution on the first device sensing response message;

means for transmitting a sleep request message to the first remote NFC device, which causes the first remote NFC device to transition to a sleep state that prohibits the first remote NFC device from responding to a first device sensing request message;

wherein the means for transmitting is further configured to transmit the first device sensing request message;

means for receiving a second device sensing response message that includes collisions among the plurality of remote NFC devices;

wherein the means for identifying is further configured to identify a second remote NFC device of the plurality of remote NFC devices by performing collision resolution on the second device sensing response message;

means for storing the first device sensing response message in a first location in a storage structure, and the second device sensing response message in a second location in the storage structure;

wherein the means for receiving is further configured to receive a collision free device sensing response message; and

means for determining collision free versions of the first and second device sensing response messages by analyzing the first device sensing response message in the first location and the second device sensing response message in the second location in the storage structure using the received collision free device sensing response message.

20. The method of claim 19 , wherein the means for transmitting is further configured to transmit a second device sensing request message as part of a technology detection process; and

wherein the means for receiving is further configured to receive the first device sensing response message in response to the second device sensing request message.

21. The apparatus of claim 19 , wherein the second device sensing response message overwrites the first device sensing response message.

22. The apparatus of claim 19 , wherein each of the plurality of remote NFC devices is configured to use NFC-A radio frequency (RF) technology.

23. The apparatus of claim 19 , wherein the first and second device sensing response messages are SENS_RES messages as defined in the NFC Forum Digital Protocol specification.

24. The apparatus of claim 19 , wherein the second device sensing request message is a SENS_REQ message as defined in the NFC Forum Digital Protocol specification.

25. The apparatus of claim 19 , wherein the sleep request message is a SLP_REQ message as defined in the NFC Forum Digital Protocol specification.

26. The apparatus of claim 19 , wherein the plurality of remote NFC devices comprise at least one of a reader device, a writer device, a tag, a card, and a peer device.

27. The apparatus of claim 19 , wherein the means for receiving and means for transmitting are further configured to perform single device detection communications with each device that transmitted a device sensing response message to obtain a NFC device identifier (NFCID).

28. An apparatus for NFC communications, comprising:

a transceiver;

a memory;

a processor coupled to the memory; and

a NFC technology detection module coupled to at least one of the memory or the processor and configured to:

determine that a first device sensing response message includes one or more collisions among a plurality of remote near field communication (NFC) devices; and

identify a first remote NFC device of the plurality of remote NFC devices by performing collision resolution on the first device sensing response message;

wherein the transceiver is configured to:

transmit a sleep request message to the first remote NFC device, which causes the first remote NFC device to transition to a sleep state that prohibits the first remote NFC device from responding to a first device sensing request message;

transmit the first device sensing request message;

receive a second device sensing response message that includes collisions among the plurality of remote NFC devices; and

wherein the NFC technology detection module is further configured to:

identify identifying a second remote NFC device of the plurality of remote NFC devices by performing collision resolution on the second device sensing response message;

wherein the memory is further configured to store the first device sensing response message in a first location in a storage structure, and the second device sensing response message in a second location in the storage structure;

wherein the transceiver is further configured to receive a collision free device sensing response message; and

wherein the NFC technology detection module is further configured to determine collision free versions of the first and second device sensing response messages by analyzing the first device sensing response message in the first location and the second device sensing response message in the second location in the storage structure using the received collision free device sensing response message.

29. The apparatus of claim 28 , wherein the transceiver is further configured to:

transmit a second device sensing request message as part of a technology detection process; and

receive the first device sensing response message in response to the second device sensing request message.

30. The apparatus of claim 28 , wherein the second device sensing response message overwrites the first device sensing response message in the memory.

31. The apparatus of claim 28 , wherein each of the plurality of remote NFC devices is configured to use NFC-A radio frequency (RF) technology.

32. The apparatus of claim 28 , wherein the first and second device sensing response messages are SENS_RES messages as defined in the NFC Forum Digital Protocol specification.

33. The apparatus of claim 28 , wherein the second device sensing request message is a SENS_REQ message as defined in the NFC Forum Digital Protocol specification.

34. The apparatus of claim 28 , wherein the sleep request message is a SLP_REQ message as defined in the NFC Forum Digital Protocol specification.

35. The apparatus of claim 28 , wherein the plurality of remote NFC devices comprise at least one of a reader device, a writer device, a tag, a card, and a peer device.

36. The apparatus of claim 28 , wherein the NFC technology detection module is further configured to perform single device detection communications with each device that transmitted a device sensing response message to obtain a NFC device identifier (NFCID).