ENCODING BEACON SIGNALS TO PROVIDE IDENTIFICATION IN PEER-TO-PEER COMMUNICATION

• US 20080037487A1
• Filed: 01/10/2007
• Published: 02/14/2008
• Est. Priority Date: 01/11/2006
• Status: Abandoned Application

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Laroia, Rajiv, Wu, Xinzhou, Li, Junyi, Richardson, Tom
• Application Number:
  US11/621,973
• Publication Number:
  US 20080037487A1
• Time in Patent Office: Days
• US Class Current: 370/338
• CPC Class Codes: H04J 3/0602 Systems characterised by the synchronising information used
• CPC Class Codes: H04L 27/2601 Multicarrier modulation systems
• CPC Class Codes: H04L 27/261 Details of reference signals
• CPC Class Codes: H04L 5/0016 Time-frequency-code
• CPC Class Codes: H04L 5/0035 Resource allocation in a cooperative multipoint environment
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• CPC Class Codes: H04W 16/14 Spectrum sharing arrangements between different networks
• CPC Class Codes: H04W 28/04 Error control
• CPC Class Codes: H04W 28/18 Negotiating wireless communication parameters
• CPC Class Codes: H04W 36/16 Performing reselection for specific purposes
• CPC Class Codes: H04W 36/24 Reselection being triggered by specific parameters
• CPC Class Codes: H04W 40/24 Connectivity information management, e.g. connectivity discovery or connectivity update
• CPC Class Codes: H04W 40/244 using a network of reference devices, e.g. beaconing
• CPC Class Codes: H04W 48/08 Access restriction or access information delivery, e.g. discovery data delivery signalling during connection H04W76/00
• CPC Class Codes: H04W 48/16 Discovering, processing access restriction or access information
• CPC Class Codes: H04W 48/20 Selecting an access point
• CPC Class Codes: H04W 52/0229 where the received signal is a wanted signal
• CPC Class Codes: H04W 52/04 TPC
• CPC Class Codes: H04W 72/02 Selection of wireless resources by user or terminal
• CPC Class Codes: H04W 76/14 Direct-mode setup
• CPC Class Codes: H04W 8/005 : Discovery of network devices, e.g. terminals
• CPC Class Codes: H04W 84/042 : Public Land Mobile systems, e.g. cellular systems
• CPC Class Codes: H04W 84/18 : Self-organising networks, e.g. ad-hoc networks or sensor networks
• CPC Class Codes: H04W 88/02 : Terminal devices
• CPC Class Codes: H04W 88/04 : adapted for relaying to or from another terminal or user
• CPC Class Codes: H04W 88/06 : adapted for operation in multiple networks or having at least two operational modes, e.g. multi-mode terminals
• CPC Class Codes: H04W 88/10 : adapted for operation in multiple networks, e.g. multi-mode access points
• CPC Class Codes: Y02D 30/70 : in wireless communication networks

Abstract

Systems and methodologies are described that facilitate encoding and/or decoding signals utilized to identify a wireless terminal during peer discovery interval(s). Substantially any type of function that constrains encoding and/or decoding within a peer-to-peer network may be utilized. For example, a reversible function may be employed that enables a receiving peer to discern an identifier of a transmitting peer over a series of peer discovery intervals. Pursuant to another example, an irreversible function may be utilized whereby a receiving peer may be unable to decipher the identifier of the transmitting peer from a received signal, however, expected signal formats of buddy peers may be compared to the received signal to determine a presence of one of the buddy peers in a vicinity.

Claims

1. A method that facilitates operating a wireless terminal in a peer-to-peer network, comprising:

receiving a sequence of first signals across a series of peer discovery intervals, wherein the first signals are generated by a disparate wireless terminal using a predetermined hash function to which wireless terminals in the peer-to-peer network abide; and

deriving an identifier from the sequence of first signals across the series of peer discovery intervals.

2. The method of claim 1, wherein the predetermined hash function is a reversible function.

3. The method of claim 1, further comprising:

receiving a second signal from a signal source, wherein the signal source includes one of a base station, an access node, or a satellite;

deriving timing information from the second signal; and

determining time positions of the peer discovery intervals in the series from the derived timing information.

4. The method of claim 3, further comprising:

receiving a third signal from the signal source;

deriving a time counter variable from the third signal, wherein a value of the time counter variable varies between two successive peer discovery intervals based on a predetermined function; and

using the time counter variable to derive the identifier.

5. The method of claim 4, wherein each of the peer discovery intervals includes a plurality of symbols and each of the plurality of symbols includes a plurality of tones and the first signals include one or a plurality of beacon signals wherein a beacon signal includes one tone in one symbol period and a received power of the one tone is at least 5 dB higher than an average per-tone power of other tones in the same symbol period.

6. The method of claim 5, further comprising

determining at least one beacon signal is present in each peer discovery interval of the series;

estimating an index of the symbol and an index of the tone of the beacon signals;

applying a predetermined linking constraint function to determine whether a first beacon signal in one peer discovery interval and a second beacon signal in a different peer discovery interval in the series are associated with the same identifier; and

using the first beacon signal and the second beacon signal to derive the identifier if the first beacon signal and the second beacon signal are determined to be associated with the same identifier.

7. The method of claim 6, wherein the predetermined linking constraint function is a constraint function that symbol indices and tone indices of the first beacon signal and the second beacon signal have to satisfy.

8. The method of claim 7, wherein the constraint function is such that the symbol index of the first beacon signal is equal to at least one of the tone index or the symbol index of the second beacon signal in a modulo sense and a modulus is a predetermined constant.

9. The method of claim 4, further comprising:

generating a disparate sequence of fourth signals based upon the predetermined hash function to encode a second identifier of the wireless terminal or a user using the wireless terminal; and

transmitting the disparate sequence of fourth signals over a second series of peer discovery intervals to enable other wireless terminals to decipher the encoded, second identifier.

10. The method of claim 9, further comprising generating each signal of the sequence of fourth signals based upon the time counter variable associated with corresponding peer discovery intervals.

11. The method of claim 1, further comprising:

linking the signals to form the sequence; and

determining the identifier from the linked signals.

12. The method of claim 1, further comprising:

storing a list of known identifiers;

comparing the derived identifier with the list to determine whether the derived identifier matches any of the known identifiers; and

determining that a corresponding wireless terminal or user is present in a vicinity if the derived identifier matches one known identifier.

13. A wireless communications apparatus, comprising:

a memory that retains instructions related to detecting a sequence of first signals during a series of peer discovery intervals, wherein the first signals are generated by a peer using a predetermined hash function that constrains peers in a peer-to-peer environment, and deriving an identifier from the sequence of first signals across the series of peer discovery intervals; and

a processor, coupled to the memory, configured to execute the instructions retained in the memory.

14. The wireless communications apparatus of claim 13, wherein the predetermined hash function is a reversible function.

15. The wireless communications apparatus of claim 13, wherein the memory further retains instructions for deriving timing information from a second signal obtained from one or more of a base station, an access node or a satellite, and determining time positions of the peer discovery intervals in the series from the derived timing information.

16. The wireless communications apparatus of claim 15, wherein the memory further retains instructions for deriving a time counter variable that varies between two successive peer discovery intervals from a third signal received from the one or more of the base station, the access node or the satellite, and using the time counter variable to derive the identifier.

17. The wireless communications apparatus of claim 16, wherein each of the peer discovery intervals includes a plurality of symbols and each of the plurality of symbols includes a plurality of tones and the first signals include one or a plurality of beacon signals wherein a beacon signal includes one tone in one symbol period and a received power of the one tone is at least 5 dB higher than an average per-tone power of other tones in the same symbol period.

18. The wireless communications apparatus of claim 17, wherein the memory further retains instructions for estimating a symbol index and a tone index of received beacon signals, determining whether a first beacon signal in one peer discovery interval and a second beacon signal in a second peer discovery interval in the series are associated with the same identifier by applying a predetermined linking constraint function, and employing the first beacon signal and the second beacon signal to derive the identifier when the first beacon signal and the second beacon signal are determined to be associated with the same identifier.

19. The wireless communications apparatus of claim 18, wherein the predetermined linking constraint function provides constraints for symbol indices and tone indices of the first beacon signal and the second beacon signal.

20. The wireless communications apparatus of claim 19, wherein the predetermined linking constraint function constrains the symbol index of the first beacon signal to be equal to one or more of the tone index or the symbol index of the second beacon signal in a modulo sense and a modulus is a predetermined constant.

21. The wireless communications apparatus of claim 16, wherein the memory further retains instructions for encoding a disparate sequence of fourth signals with a second identifier of a wireless terminal or a user of the wireless terminal by employing the predetermined hash function and sending the disparate sequence of fourth signals over a second series of peer discovery intervals to enable peers to evaluate the encoded, second identifier.

22. The wireless communications apparatus of claim 21, wherein the memory further retains instructions for encoding each signal of the disparate sequence of fourth signals based upon the time counter variable associated with corresponding peer discovery intervals.

23. The wireless communications apparatus of claim 21, wherein the memory further retains instructions for linking the first signals to form the sequence, and determining the identifier from the linked first signals.

24. The wireless communications apparatus of claim 21, wherein the memory further retains instructions for comparing the derived identifier with a stored list of known identifiers to determine whether the derived identifier matches any of the known identifiers, and determining that a corresponding wireless terminal or user is present in a vicinity if the derived identifier matches one known identifier.

25. A wireless communications apparatus that enables utilizing a reversible function in connection with peer discovery signals in a peer-to-peer network, comprising:

means for receiving a sequence of signals across a series of peer discovery intervals, the signals being generated by a disparate wireless terminal using a predetermined reversible function to which wireless terminals in a peer-to-peer network abide; and

means for deriving an identifier from the sequence of signals across the series of peer discovery intervals.

26. The wireless communications apparatus of claim 25, further comprising means for determining time positions of the peer discovery intervals in the series from timing information received from a base station, an access node, and/or a satellite.

27. The wireless communications apparatus of claim 26, further comprising means for deriving a time counter variable that changes between two successive peer discovery intervals, the time counter variable being utilized to derive the identifier.

28. The wireless communications apparatus of claim 27, wherein each of the peer discovery intervals includes a plurality of symbols and each of the plurality of symbols includes a plurality of tones and the signals include one or a plurality of beacon signals wherein a beacon signal includes one tone in one symbol period and a received power of the one tone is at least 5 dB higher than an average per-tone power of other tones in the same symbol period.

29. The wireless communications apparatus of claim 28, further comprising:

means for determining whether a first beacon signal in one peer discovery interval and a second beacon signal in a second peer discovery interval are associated with the same identifier by applying a predetermined linking constraint function; and

means for deriving the identifier based upon the first beacon signal and the second beacon signal when associated with the same identifier.

30. The wireless communications apparatus of claim 27, further comprising:

means for generating a disparate sequence of signals with the time counter variable and a disparate identifier of a wireless terminal or a user of the wireless terminal based upon the predetermined reversible function; and

means for broadcasting the disparate sequence of signals over the peer-to-peer network.

31. The wireless communications apparatus of claim 25, further comprising:

means for determining whether the derived identifier matches a known identifier from a retained list of known identifiers; and

means for identifying a corresponding peer or user as being present in a vicinity if the derived identifier matches one known identifier.

32. A machine-readable medium having stored thereon machine-executable instructions for:

receiving a sequence of first signals across a series of peer discovery intervals, wherein the first signals are generated by a disparate wireless terminal using a predetermined hash function to which wireless terminals in the peer-to-peer network abide; and

deriving an identifier from the sequence of first signals across the series of peer discovery intervals.

33. The machine-readable medium of claim 32, wherein the predetermined hash function is a reversible function.

34. The machine-readable medium of claim 32, the machine-executable instructions further comprise determining time positions of the peer discovery intervals in the series from timing information derived from a second signal, wherein the second signal is received from one or more of a base station, an access node, or a satellite.

35. The machine-readable medium of claim 34, the machine-executable instructions further comprise identifying a time counter variable to be utilized for deriving the identifier, wherein the time counter variable varies between two successive peer discovery intervals based upon a predetermined function.

36. The machine-readable medium of claim 35, wherein each of the peer discovery intervals includes a plurality of symbols and each of the plurality of symbols includes a plurality of tones and the first signals include one or a plurality of beacon signals wherein a beacon signal includes one tone in one symbol period and a received power of the one tone is at least 5 dB higher than an average per-tone power of other tones in the same symbol period.

37. The machine-readable medium of claim 36, the machine-executable instructions further comprise:

estimating a symbol index and a tone index of the beacon signals;

applying a predetermined linking constraint function to determine whether a first beacon signal in one peer discovery interval and a second beacon signal in a differing peer discovery interval in the series are associated with the same identifier; and

utilizing the first beacon signal and the second beacon signal to derive the identifier when the first beacon signal and the second beacon signal are determined to be associated with the same identifier.

38. The machine-readable medium of claim 35, the machine-executable instructions further comprise:

generating a disparate sequence of transmission signals based upon the predetermined hash function to encode a second identifier of the wireless terminal or a user using the wireless terminal; and

sending the disparate sequence over a second series of peer discovery intervals to enable other wireless terminals to decipher the encoded, second identifier.

39. In a wireless communication system, an apparatus comprising;

a processor configured to;

receive a sequence of signals across a series of peer discovery intervals, wherein the signals are generated by a disparate wireless terminal using a predetermined hash function to which wireless terminals in the peer-to-peer network abide; and

derive an identifier from the sequence of signals across the series of peer discovery intervals.