System and Method for Spectrum Management of a Shared Frequency Band

• US 20030198200A1
• Filed: 09/18/2002
• Published: 10/23/2003
• Est. Priority Date: 04/22/2002
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cognio, Inc. (Cisco Systems, Inc.)
• Inventors: Diener, Neil R., Miller, Karl A.
• Granted Patent: US 7,269,151 B2
• Time in Patent Office: Days
• US Class Current: 370/329
• CPC Class Codes: H04L 1/1664 the supervisory signal being transmitted together with payload signals; piggybacking
• CPC Class Codes: H04W 16/14 Spectrum sharing arrangements between different networks
• CPC Class Codes: H04W 72/542 using measured or perceived quality

Abstract

Abstract of Disclosure

A system and method for managing the spectrum utilization of a frequency band that is shared, both in frequency and time, by multiple devices. At one or more devices operating in the frequency band, pulses associated with signals occurring in the frequency band are detected by sampling part or all the frequency band for a time interval. From the detected signal pulses, the signals can be classified. In addition, overall spectrum activity can be measured. Using classification information for signals detected in the frequency band, policies can be executed so that a device may take certain actions in order to avoid interfering with other signals, or to optimize simultaneous use of the frequency band with the other signals. Signal detection occurs at one or more devices operating in a frequency band. Signal classification and measurement, as well as policy execution may occur within a processor of the same device where signal detection occurs, or in another device (located remotely or within the operating region of the frequency band).

Claims

1. A method is provided for managing usage of a radio frequency band that is shared by multiple devices, comprising steps of:

2. The method of claim 1, wherein the step of monitoring comprises sampling substantially all the frequency band using a wideband radio transceiver in the device to obtain activity in the frequency band.

3. The method of claim 2, wherein the step of monitoring activity comprises generating spectral-based and time-based information pertaining to activity in the frequency band.

4. The method of claim 1, wherein the step of processing is performed by a device located remote from the device where activity in the frequency band is monitored.

5. The method of claim 1, wherein the step of controlling comprises generating control signals for controlling one or more operating parameters of devices operating in the frequency band, including:

frequency channel assignment, transmission data rate, packet fragment size, packet transmit scheduling to avoid interfering with other signals, and transmit power.

6. The method of claim 1, wherein the step of monitoring activity in the frequency band comprises obtaining spectrum analysis information for the frequency band.

7. The method of claim 6, wherein the step of processing information comprises accumulating spectrum analysis information for intervals of time.

8. The method of claim 1, wherein the step of processing spectrum activity information comprises classifying or identifying devices operating in the frequency band.

9. The method of claim 1, wherein the step of processing spectrum activity information comprises executing one or more spectrum policies to determine what actions, if any, should be taken by one or more devices operating in the frequency band.

12. The method of claim 9, wherein the step of processing spectrum activity information comprises executing a spectrum policy that assigns a higher level of priority of usage of the frequency band to one or more signals over other signals.

13. The method of claim 12, wherein the step of processing spectrum activity information comprises executing the spectrum policy that assigns higher priority to a radar signal in a 5 GHz radio frequency band over other signals in that radio frequency band.

14. The method of claim 9, wherein the step of executing spectrum policies comprises executing a spectrum policy that maximizes a transmit data rate of a device given presence of any other signals in the frequency band.

15. The method of claim 14, wherein the step of executing the spectrum policy comprises limiting a transmit data rate if there is a frequency hopping signal also occurring in the frequency band.

16. The method of claim 9, wherein the step of executing spectrum policies comprises executing a spectrum policy that assigns priority to certain types of signals over others based on the time of day or locations of devices.

17. The method of claim 9, wherein the step of executing spectrum policies comprises executing a spectrum policy that is based on regulatory specific policies governing the use by devices of the frequency band.

10. The method of claim 10, wherein the step of executing spectrum policies comprises executing one or more of actions selected from the group consisting of:

frequency channel assignment, transmission data rate, packet fragment size, packet transmit scheduling to avoid interfering with other signals, and transmit power.

11. The method of claim 10, wherein the step of executing spectrum policies further comprises fragmenting a packet to be transmitted before a next interference period determined to occur.

18. In a device that operates in a radio frequency band that is shared by multiple devices, a method comprising steps of:

19. The method of claim 18, wherein the step of monitoring comprises:

20. The method of claim 18, and further comprising storing information describing the spectrum policies in the device.

21. The method of claim 20, and further comprising downloading updated or new spectrum policies to the device from another device.

22. The method of claim 18, and further comprising reporting signal classification information to another device that processes the signal classification information according to spectrum policies.

23. A system for managing spectrum usage by one or more devices in a radio frequency band, comprising:

24. The system of claim 23, wherein the processor generates signals to control operation of one or more devices in the frequency based on the signals determined to occur in the frequency band and according to spectrum policies.

25. The system of claim 24, and further comprising a memory for storing spectrum policies.

26. The device of claim 23, and further comprising a memory that stores a database of signal classification reference data, wherein the processor compares information output by the spectrum analysis device with the signal classification data to classify a signal.

27. The system of claim 26, wherein the memory stores updated or new signal classification reference data downloaded from another device.

28. A method for generating spectrum policies useful to manage use of a frequency band that is shared by multiple devices, comprising steps of:

29. The method of claim 28, wherein the step of receiving information comprises receiving from a user including one or more of:

information identifying whether a network to be deployed in the radio frequency band is a home network or an office network, information identifying how many access point devices are present in the network, and information identifying how many cordless telephones are operating in the frequency band.

30. A processor readable medium encoded with instructions that, when executed by a processor, cause the processor to perform steps of:

31. The processor readable medium of claim 30, wherein the instructions encoded on the medium for receiving information comprise instructions for receiving from a user including one or more of:

information identifying whether a network to be deployed in the radio frequency band is a home network or an office network, information identifying how many access point devices are present in the network, and information identifying how many cordless telephones are operating in the frequency band.

32. A system for managing use of a radio frequency band shared by multiple devices, comprising:

33. The system of claim 32, wherein the first level of one or more software programs comprises a spectrum analysis manager program that controls the spectrum analysis device and a measurement program that accumulates spectrum activity information output by the spectrum analysis device.

34. The system of claim 32, wherein the second level of one or more software programs comprises a signal classification program that classifies signals in the frequency band based on information output by the spectrum analysis device.

35. The system of claim 34, wherein the second level of one or more software programs comprises a spectrum policy program that, based on signals determined to be in the frequency band, generates control signals that are coupled to the first level of one or more software programs to control how the first device operates in the frequency band according to one or more spectrum policies.

36. The system of claim 35, wherein the radio receiver in the first device further comprises a radio transmitter capable of transmitting a signal in the frequency band, and wherein the processor is responsive to control signals generated by the spectrum policy program to control how signals are transmitted by the radio transmitter.

37. The system of claim 35, wherein the third level of one or more software programs comprises a policy manager program that provides new or updated spectrum policies to the spectrum policy program in the second level.

38. The system of claim 34, wherein the third level of one or more software programs comprises a classification manager program that provides new or updated signal classification reference data to the signal classification program in the second level.

39. The system of claim 33, wherein the third level of one or more software programs comprises a measurement program that interfaces with the measurement program of the first level and further accumulates spectrum activity information.

40. The system of claim 32, and further comprising software interfaces between the first level and second level of software programs and between the second level and the third level of software programs, whereby the interfaces manage the exchange of data between levels according to application program interfaces.

41. The system of claim 32, and further comprising a fourth level of one or more software programs executed by the process of the computing device.

42. The system of claim 41, wherein the fourth level of one or more software programs comprises one or more of:

a spectrum analyzer application program to generate spectrum analyzer data for display based on the spectrum activity information;

a policy application that defines spectrum policies that are coupled to the policy manager program;

a classification definition application that generates signal classification reference data that is supplied to the classification manager program.

43. The system of claim 32, wherein the first device is coupled to the second device by one of a wireless link or a wired link.

44. A software system for managing use of a radio frequency band shared by multiple devices, comprising:

45. The software system of claim 44, and further comprising a fifth level of one or more software application programs that interface with the third level of software programs including one or more of:

a spectrum analyzer application program to generate spectrum analyzer data for display based on the spectrum activity information;

a policy application that defines spectrum policies that are coupled to the policy manager program;

a classification definition application that generates signal classification reference data that is supplied to the classification manager program.

46. The software system of claim 44, wherein the third level of software programs includes a software program that classifies signals based on the accumulated spectrum activity information.

47. The software system of claim 46, wherein the third level of software programs includes a spectrum policy program that, based on signals determined to be in the frequency band, generates control signals that are coupled to the first level of one or more software programs to control how a device operates in the frequency band according to one or more spectrum policies.

48. The software system of claim 47, wherein the fourth level of software programs comprises a policy manager program that provides new or updated spectrum policies to the spectrum policy program in the second level.

49. The software system of claim 46, wherein the fourth level of software programs comprises a classification manager program that provides new or updated signal classification reference data to the signal classification program in the second level.

50. The software system of claim 44, and further comprising software interfaces between the levels of software programs, whereby the interfaces manage the exchange of data between levels according to application program interfaces.

51. A processor readable medium encoded with instructions that, when executed by a processor, cause the processor to perform steps of:

52. A method for accumulating statistics associated with activity in a radio frequency band shared by a plurality of devices, comprising steps of:

53. The method of claim 52, wherein the step of accumulating data comprises accumulating for each frequency bin statistics including one or more selected from the group consisting of:

signal pulse duty cycle, maximum signal power, average signal power, network type and network traffic conditions and activity.

54. The method of claim 52, wherein the step of receiving data comprises receiving output from a spectrum analyzer in a device that receives signals in the frequency band.

55. The method of claim 52, wherein the step of detecting activity in the frequency band comprises operating a radio receiver in a wideband mode so as to receive energy in substantially the entire frequency band during time intervals.

56. The method of claim 52, wherein the step of accumulating comprises accumulating statistics associated with signal pulses detected in the frequency band, including one or more statistics selected from the group consisting of:

number of signal pulses concurrent in the frequency band, signal pulse center frequency, signal pulse bandwidth, signal pulse duration, time between signal pulses and signal pulse power.

57. The method of claim 52, and further comprising displaying the data.