Encoding information in beacon signals

• US 8,488,477 B2
• Filed: 06/15/2007
• Issued: 07/16/2013
• Est. Priority Date: 06/16/2006
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Li, Junyi, Richardson, Thomas, Laroia, Rajiv
• Primary Examiner(s): Pham, Chi
• Assistant Examiner(s): Elallam, Ahmed
• Application Number:
  US11/764,156
• Publication Number:
  US 20080009305A1
• Time in Patent Office: 2,223 Days
• Field of Search: 370/203, 370/208, 370/252, 370/328, 370/329, 370/330, 370/295, 370/344, 370/480, 370/482, 375/260, 455/222, 455/522
• US Class Current: 370/252
• CPC Class Codes: H04L 27/261 Details of reference signals
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/0051 of dedicated pilots, i.e. pilots destined for a single user or terminal
• CPC Class Codes: H04L 5/0053 Allocation of signaling, i.e. of overhead other than pilot signals
• CPC Class Codes: H04L 5/0064 Rate requirement of the data, e.g. scalable bandwidth, data priority
• CPC Class Codes: H04W 4/06 Selective distribution of broadcast services, e.g. multimedia broadcast multicast service [MBMS]; Services to user groups; One-way selective calling services
• CPC Class Codes: H04W 72/30 Resource management for broadcast services

Abstract

Systems and methodologies are described that facilitate transmitting at least two different types of information in a single signal, whereby the different types of information can be encoded and decoded independently. Thus, changes to one type of information does not affect a second type of information.

Claims

1. A method of transmitting a set of broadcast information bits using a predetermined set of bandwidth degrees of freedom, wherein a degree of freedom comprises a tone in an OFDM transmission symbol, the method comprising:

generating from a plurality of broadcast information bits a first subset of broadcast information bits and a second subset of broadcast information bits;

partitioning a predetermined set of bandwidth of degrees of freedom into at least two subsets, each subset including a plurality of bandwidth degrees of freedom;

choosing a subset from the at least two subsets of bandwidth degrees of freedom as a function of the first subset of broadcast information bits;

selecting at least one of the bandwidth degrees of freedom in the chosen subset as a function of the second subset of broadcast information bits; and

transmitting a beacon signal in the at least one selected bandwidth degree of freedom.

2. The method of claim 1, wherein the beacon signal is transmitted at a power in each selected bandwidth degree of freedom that is X dB higher than the average transmission power used in each non-selected degree of freedom in the set of bandwidth degrees of freedom, X being at least 10 dB.

3. The method of claim 1, wherein partitioning the at least two subsets of bandwidth degrees of freedom is performed in a predetermined manner and independently of the set of broadcast information bits.

4. The method of claim 3, wherein the bandwidth degrees of freedom in any of the at least two subsets are contiguous.

5. The method of claim 3, wherein the at least two subsets are disjoint with each other.

6. The method of claim 1, wherein the first and second subsets of broadcast information bits are disjoint subsets of the set of broadcast information bits.

7. The method of claim 1, wherein at least one subset of the at least two subsets of broadcast information bits includes control information to be received by a wireless device for peer-to-peer communications in which a wireless device communicates directly with another wireless device.

8. The method of claim 7, wherein the control information includes at least one of a frequency band location information, whether peer-to-peer communication is allowed in the frequency band, a control parameter that controls a maximum transmission power to be used by the wireless device for peer-to-peer communications or combinations thereof.

9. A wireless communications apparatus that transmits a set of broadcast information bits, comprising:

a memory that retains instructions related to generating a first subset of broadcast information bits and a second subset of broadcast information bits, partitioning a set of bandwidth degrees of freedom into two or more wherein a degree of freedom comprises a tone in an OFDM transmission symbol, deciding which subset to use as a function of the first subset of broadcast information bits, choosing one or more bandwidth degrees of freedom in the subset as a function of the second subset of broadcast information and sending the chosen one or more bandwidth degrees of freedom in a beacon signal; and

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

10. The wireless communications apparatus of claim 9, the memory further retains instructions for transmitting the beacon signal at a power in each selected bandwidth degree of freedom that is X dB higher than an average transmission power used to transmit other beacon signals, X being at least 10 dB.

11. The wireless communications apparatus of claim 9, wherein the memory further retains instructions for partitioning the two or more subsets of bandwidth degrees of freedom in a predetermined manner and independently of the set of broadcast information bits.

12. The wireless communications apparatus of claim 9, wherein the two or more subsets are disjoint with each other.

13. The wireless communications apparatus of claim 9, wherein the first and second subsets of broadcast information bits are disjoint subsets of the set of broadcast information bits.

14. A wireless communications apparatus that enables independent coding of at least two subsets of information in a beacon signal, comprising:

means for creating a first subset of broadcast information bits and a second subset of broadcast information bits from a plurality of broadcast information bits;

means for dividing a set of bandwidth degrees of freedom into at least two subsets wherein a degree of freedom comprises a tone in an OFDM transmission symbol;

means for choosing one subset from the at least two subsets as a function of the first subset of broadcast information bits;

means for independently selecting at least one of the bandwidth degrees of freedom in the chosen subset as a function of the second subset of broadcast information; and

means for selectively transmitting information in the at least one bandwidth degree of freedom.

15. The wireless communications apparatus of claim 14, further comprising means for transmitting the beacon signal at a power in each selected bandwidth degree of freedom that is at least 10 dB higher than an average transmission power used in each non-selected degree of freedom in the set of bandwidth degrees of freedom.

16. The wireless communication apparatus of claim 14, the means for selectively transmitting sends the first and the at least a second subset of information at a high-energy.

17. A non-transitory machine-readable medium having stored thereon machine-executable instructions for:

producing a first and a second subset of broadcast information bits;

dividing a set of bandwidth degrees of freedom into two or more subsets from a plurality of broadcast information bits, wherein a degree of freedom is a tone in an OFDM transmission symbol;

selecting a subset from the two or more subsets as a function of the first subset of broadcast information bits;

selecting at least one the set of bandwidth degrees of freedom in the selected subset as a function of the second subset of broadcast information bits; and

transmitting a beacon signal in the at least one selected bandwidth degree of freedom.

18. The non-transitory machine-readable medium of claim 17, the machine-executable instructions further comprise transmitting the beacon signal at a power in each selected bandwidth degree of freedom that is at least 10 dB higher than the average transmission power used in non-selected degrees of freedom.

19. The non-transitory machine-readable medium of claim 17, where dividing the set of bandwidth degrees of freedom is performed in a predetermined manner and independently of the set of broadcast information bits.

20. In a wireless communication system, an apparatus comprising:

a processor configured to;

create a first and a second subset of broadcast information bits from a plurality of broadcast information bits;

divide a set of bandwidth degrees of freedom into at least two subsets in a predetermined manner and independently of the set of broadcast information bits;

choose a subset from the at least two subsets of bandwidth degrees of freedom as a function of the first subset of broadcast information bits wherein a degree of freedom comprises a tone in an OFDM transmission symbol;

select at least one of the bandwidth degrees of freedom in the chosen subset as a function of the second subset of broadcast information bits; and

transmit a beacon signal in the at least one selected bandwidth degree of freedom at a power in each selected bandwidth degree of freedom that is X dB higher than an average transmission power used in each non-selected degree of freedom in the set of bandwidth degrees of freedom, X being at least 10 db.

21. A method for receiving a set of broadcast information bits, comprising:

receiving a beacon symbol in at least one bandwidth degree of freedom, wherein;

a degree of freedom comprises a tone in an OFDM transmission symbol;

and the beacon symbol is received in the at least one selected bandwidth degree of freedom at a power higher than other bandwidth degrees of freedom;

determining which bandwidth degree of freedom was selected from the plurality of bandwidth degrees of freedom included in a subset; and

ascertaining which subset was selected from at least two subsets of bandwidth degrees of freedom to determine at least a portion of the set of broadcast information.

22. The method of claim 21, wherein the beacon symbol is received at a power in each selected bandwidth degree of freedom that is X dB higher than an average transmission power used in a non-selected degree of freedom in the set of bandwidth degrees of freedom, X being at least 10 dB.

23. The method of claim 21, the beacon symbol is received at substantially a same time as other signals.

24. The method of claim 21, wherein determining which bandwidth degree of freedom was selected is performed independently of ascertaining which subset was selected.

25. The method of claim 24, wherein the bandwidth degrees of freedom in any of the at least two subsets are contiguous.

26. The method of claim 24, wherein the at least two subsets are disjoint with each other.

27. The method of claim 21, wherein at least two subsets of the set of broadcast information are disjoint subsets of the set of broadcast information bits.

28. The method of claim 21, wherein at least one subset of at least two subsets of the set of broadcast information includes control information to be received from a base station for peer-to-peer communications in which a first wireless device communicates directly with a second wireless device.

29. The method of claim 28, wherein the control information includes at least one of a frequency band location information, whether peer-to-peer communication is allowed in the frequency band, a control parameter that controls a maximum transmission power to be used by the first wireless device for peer-to-peer communications or combinations thereof.

30. A wireless communications apparatus that selectively decodes information received in a beacon signal including a set of broadcast information bits, the apparatus comprising:

a memory that retains instructions related to receiving a chosen one or more bandwidth degrees of freedom in a beacon signal, determining which bandwidth degrees of freedom was received from a subset, wherein a degree of freedom comprises a tone in an OFDM transmission symbol, deciding which subset was selected from two or more subsets and reconstructing a set of bandwidth degrees of freedom from the two or more subsets; and

identifying the beacon signal as being received at a power in each selected bandwidth degree of freedom higher than an average transmission power of other received beacon signals; and

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

31. The wireless communications apparatus of claim 30, the memory further retains instructions for identifying the beacon signal as being received at the power in each selected bandwidth degree of freedom that is X dB higher than the average transmission power of other received beacon signals, X being at least 10 dB.

32. The wireless communications apparatus of claim 31, wherein the two or more subsets are disjoint with each other.

33. The wireless communications apparatus of claim 32, wherein two or more subsets of broadcast information bits are disjoint subsets of the set of broadcast information bits.

34. A wireless communications apparatus that enables independent decoding of at least two subsets of broadcast information bits received in a beacon signal, comprising:

means for selectively receiving information in at least one selected bandwidth degree of freedom, wherein a degree of freedom comprises a tone in an OFDM transmission symbol and the beacon signal is received at a power in the at least one selected bandwidth degree of freedom that is higher than an average transmission power received for one or more non-selected degrees of freedom;

means for independently determining which one of a plurality of bandwidth degrees of freedom in a chosen subset was received;

means for deciding which subset from at least two subsets included the at least one of a plurality of bandwidth degrees of freedom;

means for combining the at least two subsets into a set of bandwidth degrees of freedom; and

means for decoding a plurality of broadcast information bits from the first subset of broadcast information bits and the second subset of broadcast information bits.

35. The wireless communications apparatus of claim 34, further comprising means for receiving the beacon signal at a power in each selected bandwidth degree of freedom that is at least 10 dB higher than the average transmission power received for each non-selected degree of freedom in the plurality of bandwidth degrees of freedom.

36. The wireless communications apparatus of claim 34, the means for selectively receiving accepts the information at a high-energy.

37. A non-transitory machine-readable medium having stored thereon machine-executable instructions for:

receiving a beacon signal in at least one selected bandwidth degree of freedom, wherein a degree of freedom comprises a tone in an OFDM transmission symbol, and the beacon signal is received at a power in each selected bandwidth degree of freedom that is higher than an average transmission power received for non-selected degrees of freedom;

determining which bandwidth degree of freedom in a subset that includes a plurality of bandwidth degrees of freedom was received; and

ascertaining which subset of broadcast information bits were chosen from at least two subsets for the beacon signal.

38. The non-transitory machine-readable medium of claim 37, the machine-executable instructions further comprise receiving the beacon signal at a power in each selected bandwidth degree of freedom that is at least 10 dB higher than the average transmission power received for the non-selected degrees of freedom.

39. The non-transitory machine-readable medium of claim 37, where determining which bandwidth degree of freedom was received is independent of ascertaining which broadcast information bits were chosen.

40. In a wireless communication system, an apparatus comprising:

a processor configured to;

receive a beacon signal in at least one selected bandwidth degree of freedom at a power in each selected bandwidth degree of freedom that is X dB higher than an average transmission power used in each non-selected degree of freedom in a set of bandwidth degrees of freedom, X being at least 10 dB, and wherein a degree of freedom comprises a tone in an OFDM transmission symbol;

determine at least one of the bandwidth degrees of freedom in a chosen subset that the beacon signal was received in; and

ascertain which subset of bandwidth degrees of freedom from at least two subsets a set of bandwidth degrees of freedom was divided.