Transmitter quieting during spectrum sensing

• US 8,537,772 B2
• Filed: 07/01/2010
• Issued: 09/17/2013
• Est. Priority Date: 07/02/2009
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Raveendran, Vijayalakshmi R.
• Primary Examiner(s): JAIN, RAJ K
• Application Number:
  US12/829,274
• Publication Number:
  US 20110002405A1
• Time in Patent Office: 1,174 Days
• Field of Search: None
• US Class Current: 370/330
• CPC Class Codes: H04H 20/12 Arrangements for observation, testing or troubleshooting
• CPC Class Codes: H04H 20/26 Arrangements for switching distribution systems
• CPC Class Codes: H04H 60/07 characterised by processes or methods for the generation
• CPC Class Codes: H04H 60/41 for identifying broadcast space, i.e. broadcast channels, broadcast stations or broadcast areas
• CPC Class Codes: H04H 60/80 characterised by transmission among terminal devices

Abstract

In general, this disclosure relates to techniques for quieting data transmission functionality during spectrum sensing operations. In one aspect, a method for spectrum sensing comprises detecting, during at least one time interval, whether any channel of a spectrum is available for use, and refraining, during the at least one time interval, from transmitting any data from a communication device.

Claims

1. A method for spectrum sensing, comprising:

refraining, during a first time interval, from transmitting any data from a communication device;

detecting, during the first time interval, whether a first group of channels of a spectrum is available for use;

assigning one or more quality values to the first group of channels based upon qualities of detected signals associated with the first group of channels;

selecting a second group of channels based upon the one or more quality values assigned to the first group of channels, wherein the second group of channels comprises a subset of the first group of channels; and

detecting, during a second and subsequent time interval, whether the second group of channels of the spectrum is available for use.

2. The method of claim 1, further comprising:

identifying at least one available channel in the spectrum; and

transmitting data of a digital broadcast format in the at least one identified available channel.

3. The method of claim 2, wherein identifying the at least one available channel in the spectrum comprises identifying the at least one available channel in an unused portion of a broadcast television spectrum.

4. The method of claim 2, wherein identifying the at least one available channel comprises identifying television band white space.

5. The method of claim 2, wherein the digital broadcast format comprises an ATSC (Advanced Television Systems Committee) format, a T-DMB (Terrestrial Digital Multimedia Broadcasting) format, a DVB (Digital Video Broadcasting) format, an Integrated Services Digital Broadcasting Terrestrial (ISDB-T) format, or a Moving Picture Experts Group Transport Stream (MPEG-TS) format.

6. The method of claim 2, further comprising:

detecting, during a third time interval, whether the at least one identified available channel is still available or has become occupied by another user.

7. The method of claim 1, wherein the detecting, during the first time interval, whether the first group of channels of the spectrum is available for use comprises using a spectrum sensor to determine whether the first group of channels of the spectrum is available for use.

8. The method of claim 1, further comprising:

refraining, during the second and subsequent time interval, from transmitting any data from the communication device.

9. The method of claim 8, wherein the refraining comprises turning off or disabling transmission functionality of the communication device during the first and the second time intervals.

10. The method of claim 1, wherein the first and the second time intervals are of different duration.

11. The method of claim 1, further comprising:

changing a frequency at which the detecting occurs during the first and the second time intervals.

12. The method of claim 1, further comprising generating a data stream that includes transmission data and miscellaneous data, wherein the refraining comprises refraining, during the first time interval, from transmitting the miscellaneous data of the data stream.

13. The method of claim 12, wherein the miscellaneous data comprises null or redundant data.

14. The method of claim 12, further comprising:

refraining, during a third time interval, from detecting whether any channel of the spectrum is available for use; and

transmitting, during the third time interval, the transmission data of the data stream.

15. The method of claim 12, further comprising:

selecting the first time interval to occur prior to a scene change or acquisition point in the transmission data of the data stream.

16. The method of claim 12, further comprising:

inserting one or more error correction codes into the transmission data of the data stream for use by a data receiver upon receipt of the transmission data.

17. The method of claim 1, further comprising:

generating a control signal to identify a time associated with transmitter blanking; and

refraining from transmitting any data from the communication device in response to the control signal.

18. The method of claim 17, wherein the control signal is a first control signal, the method further comprising:

generating a second control signal, wherein the second control signal causes a modulator to insert non-essential data into a modulated bitstream at a time corresponding to the first time interval.

19. The method of claim 18, wherein generating the second control signal occurs prior to generating the first control signal.

20. The method of claim 18, wherein generating the second control signal occurs at substantially the same time as generating the first control signal.

21. The method of claim 18, further comprising generating a third control signal, wherein the third control signal identifies the first time interval to an encoder.

22. The method of claim 21, wherein generating the third control signal occurs at substantially the same time as generating the first control signal and the second control signal.

23. The method of claim 21, wherein generating the third control signal occurs prior to generating the first control signal.

24. A communication system comprising:

one or more processors;

a transmitter operable by the one or more processors to refrain, during a first time interval, from transmitting any data from the communication system;

a channel identifier operable by the one or more processors to;

detect, during the first interval, whether a first group of channels of a spectrum is available for use; and

detect, during a second and subsequent time interval, whether a second group of channels is available for use, wherein the second group of channels comprises a subset of the first group of channels; and

the one or more processors is operable to;

assign one or more quality values to the first group of channels based upon qualities of detected signals associated with the first group of channels; and

select the second group of channels based upon the quality values assigned to the first group of channels.

25. The communication system of claim 24, wherein:

the channel identifier is further operable to identify at least one available channel in the spectrum; and

the transmitter is further operable to transmit data of a digital broadcast format in the at least one identified available channel.

26. The communication system of claim 24, wherein the digital broadcast format comprises an ATSC (Advanced Television Systems Committee) format, a T-DMB (Terrestrial Digital Multimedia Broadcasting) format, a DVB (Digital Video Broadcasting) format, an Integrated Services Digital Broadcasting Terrestrial (ISDB-T) format, or a Moving Picture Experts Group Transport Stream (MPEG-TS) format.

27. The communication system of claim 24, wherein the channel identifier is further operable to detect, during a third time interval, whether the at least one identified available channel is still available or has become occupied by another user.

28. The communication system of claim 24, wherein the channel identifier uses a spectrum sensor to determine whether the first group of channels of the spectrum are available for use.

29. The communication system of claim 24, wherein the transmitter is further operable to refrain, during the second and subsequent time interval, from transmitting any data from the communication system.

30. The communication system of claim 24, wherein the first and the second time intervals are of different duration.

31. The communication system of claim 24, wherein the channel identifier is further operable to change a frequency at which the detecting occurs during the first and the second time intervals.

32. The method of claim 29, wherein the transmitter turns off or disables transmission functionality of the communication device during the first and second time intervals.

33. The communication system of claim 24, wherein:

the one or more processors are further operable to generate a data stream that includes transmission data and miscellaneous data; and

the transmitter is operable to refrain, during the first time interval, from transmitting the miscellaneous data of the data stream.

34. The communication system of claim 33, wherein the miscellaneous data comprises null or redundant data.

35. The communication system of claim 33, wherein:

the channel identifier is operable to refrain, during a third time interval, from detecting whether any channel of the spectrum is available for use; and

the transmitter is operable to transmit, during the third time interval, the transmission data of the data stream.

36. The communication system of claim 33, wherein the one or more processors are further operable to select the first time interval to occur prior to a scene change or acquisition point in the transmission data of the data stream.

37. The communication system of claim 24, wherein the communication system comprises a wireless communication device handset.

38. The communication system of claim 24, wherein the communication system comprises one or more integrated circuit devices.

39. The communication system of claim 24, further comprising:

a controller that generates a control signal to identify a time associated with transmitter blanking,

wherein the transmitter refrains from transmitting any data from the communication device in response to the control signal.

40. The communication system of claim 39, wherein the control signal is a first control signal and the controller generates a second control signal, wherein the communication system includes a modulator and the second control signal causes the modulator to insert non-essential data into a modulated bitstream at a time corresponding to the first time interval.

41. The communication system of claim 40, wherein the controller generates the second control signal prior to generating the first control signal.

42. The communication system of claim 40, wherein the controller generates the second control signal at substantially the same time as generating the first control signal.

43. The communication system of claim 40, wherein the controller generates a third control signal, wherein the third control signal identifies the first time interval to an encoder.

44. The communication system of claim 43, wherein the controller generates the third control signal prior to generating the first control signal.

45. The communication system of claim 43, wherein the controller generates the third control signal at substantially the same time as generating the first control signal and the second control signal.

46. A communication system, comprising:

means for refraining, during a first time interval, from transmitting any data from a communication device;

means for detecting, during the first time interval, whether a first group of channels of a spectrum is available for use;

means for assigning one or more quality values to the first group of channels based upon qualities of detected signals associated with the first group of channels;

means for selecting a second group of channels based upon the one or more quality values assigned to the first group of channels, wherein the second group of channels comprises a subset of the first group of channels; and

means for detecting, during a second and subsequent time interval, whether the second group of channels of the spectrum is available for use.

47. The communication system of claim 46, further comprising:

means for identifying at least one available channel in the spectrum; and

means for transmitting data of a digital broadcast format in the at least one identified available channel, wherein the digital broadcast format comprises an ATSC (Advanced Television Systems Committee) format, a T-DMB (Terrestrial Digital Multimedia Broadcasting) format, a DVB (Digital Video Broadcasting) format, an Integrated Services Digital Broadcasting Terrestrial (ISDB-T) format, or a Moving Picture Experts Group Transport Stream (MPEG-TS) format.

48. The communication system of claim 46, further comprising:

means for refraining, during the second and subsequent time interval, from transmitting any data from the communication device.

49. The communication system of claim 46, wherein the first and second time intervals are of different duration.

50. The communication system of claim 46, further comprising means for generating a data stream that includes transmission data and miscellaneous data, wherein the means for refraining comprises means for refraining, during the first time interval, from transmitting the miscellaneous data of the data stream.

51. The communication system of claim 50, further comprising:

means for selecting the first time interval to occur prior to a scene change or acquisition point in the transmission data of the data stream.

52. The communication system of claim 46, further comprising means for generating one or more control signals to cause the refraining.

53. A computer-readable storage medium comprising instructions for causing one or more processors to:

refrain, during a first time interval, from transmitting any data from a communication device;

detect, during the first time interval, whether a first group of channels of a spectrum is available for use;

assign one or more quality values to the first group of channels based upon qualities of detected signals associated with the first group of channels;

select a second group of channels based upon the one or more quality values assigned to the first group of channels, wherein the second group of channels comprises a subset of the first group of channels; and

detect, during a second and subsequent time interval, whether the second group of channels of the spectrum is available for use.

54. The computer-readable storage medium of claim 53, further comprising instructions to:

identify at least one available channel in the spectrum; and

transmit data of a digital broadcast format in the at least one identified available channel, wherein the digital broadcast format comprises an ATSC (Advanced Television Systems Committee) format, a T-DMB (Terrestrial Digital Multimedia Broadcasting) format, a DVB (Digital Video Broadcasting) format, an Integrated Services Digital Broadcasting Terrestrial (ISDB-T) format, or a Moving Picture Experts Group Transport Stream (MPEG-TS) format.

55. The computer-readable storage medium of claim 53, further comprising instructions to refrain, during a second and subsequent time interval, from transmitting any data from the communication device.

56. The computer-readable storage medium of claim 53, wherein the first and second time intervals are of different duration.

57. The computer-readable storage medium of claim 53, further comprising instructions to generate a data stream that includes transmission data and miscellaneous data, wherein the instructions to refrain comprise instructions to refrain, during the first time interval, from transmitting the miscellaneous data of the data stream.

58. The computer-readable storage medium of claim 57, further comprising instructions to:

select the first time interval to occur prior to a scene change or acquisition point in the transmission data of the data stream.

59. The computer-readable storage medium of claim 53, further comprising instructions that cause generation of one or more control signals, wherein the generated control signals cause the one or more processors to refrain, during the first time interval, from transmitting any data from a communication device.

60. A method comprising:

transmitting data via a transmitter;

periodically blanking the transmitter during a first time interval and a second time interval;

detecting, during the first time interval, whether a first group of channels of a spectrum is available for use;

assigning one or more quality values to the first group of channels based upon qualities of detected signals associated with the first group of channels;

selecting a second group of channels based upon the one or more quality values assigned to the first group of channels, wherein the second group of channels comprises a subset of the first group of channels; and

detecting, during the second time interval, whether the second group of channels is available for use.