Automated real-time site survey in a shared frequency band environment

• US 7,110,756 B2
• Filed: 08/02/2004
• Issued: 09/19/2006
• Est. Priority Date: 10/03/2003
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cognio, Inc. (Cisco Systems, Inc.)
• Inventors: Diener, Neil R.
• Primary Examiner(s): D AGOSTA, STEPHEN M
• Application Number:
  US10/909,455
• Publication Number:
  US 20050073983A1
• Time in Patent Office: 778 Days
• Field of Search: 415/423, 415/424, 415/425, 415456-457, 415/501, 415/63.1, 415/67.11, 415/67.13, 370/333, 370/338, 379/21, 379/32.01
• US Class Current: 455/423
• CPC Class Codes: H04W 16/18 Network planning tools
• CPC Class Codes: H04W 16/20 for indoor coverage or short range network deployment
• CPC Class Codes: H04W 24/00 Supervisory, monitoring or testing arrangements
• CPC Class Codes: H04W 64/00 Locating users or terminals or network equipment for network management purposes, e.g. mobility management
• CPC Class Codes: H04W 72/00 Local resource management
• CPC Class Codes: H04W 84/18 Self-organising networks, e.g. ad-hoc networks or sensor networks

Abstract

An intelligent spectrum management (ISM) system and method that includes sophisticated features to detect, classify, and locate sources of RF activity. The system comprises one or more radio sensor devices positioned at various locations in a region where activity in a shared radio frequency band is occurring. A server is coupled to the radio sensor devices and aggregates the data generated by the sensor devices. The server receives data from each of the plurality of sensor devices and executes functions to process the data. One feature of the system is to correlate data collected from the sensor or from suitably equipped devices that operate (and may move about) in a space with locations where provocation of that data occurs. To this end, radio frequency energy is received at each of a plurality of known positions (e.g., the sensors) in a space. The positions in the space of one or more devices emitting radio frequency energy in the space is determined from the received radio frequency energy at the plurality of known positions (e.g., the sensors). A variety of positioning techniques may be employed, such as received signal strength, time-difference-of arrival, time-of-arrival, etc. Activity data representing characteristics of received radio frequency energy in the space is generated at the sensors or at suitable equipped devices that may move about the space. The server correlates the activity data with the positions in the space that are associated with the provocation of the activity data.

Claims

1. A method for monitoring wireless activity in a radio frequency band, comprising:

a. receiving radio frequency energy at each of a plurality of known positions in a space;

b. determining positions in the space of one or more devices emitting radio frequency energy in the space from the received radio frequency energy at the plurality of known positions;

c. detecting signals occurring according to a communication protocol at the one or more devices in the space that operate according to the communication protocol;

d. generating protocol activity data representing characteristics of received radio frequency energy in the space, wherein the protocol activity data represents characteristics of signals transmitted according to a communication protocol in the frequency band, wherein the protocol activity data is generated based upon the signals detected at the one or more devices;

e. correlating the protocol activity data with the positions in the space that are associated with provocation of the protocol activity data;

f. displaying the protocol activity data on a map at positions in the space associated with the occurrence of the signals that led to generation of the protocol activity data; and

g. tracking movement of the one or more devices through the space.

2. The method of claim 1, wherein generating protocol activity data comprises generating data representing the performance of communication occurring according to the communication protocol, including one or more of:

average data rate, number of packet resends and number of devices operating occurring to the communication protocol.

3. The method of claim 1, wherein determining positions comprises computing positions of the one or more devices based on signals received at each of the plurality of known positions.

4. The method of claim 1, wherein correlating comprises correlating the protocol activity data derived from signals detected by the one or more devices with the positions of the one or more devices.

5. The method of claim 1, wherein detecting signals comprises detecting signals occurring according to the communication protocol at the plurality of known positions from the one or more devices in the space that operate according to the communication protocol.

6. The method of claim 5, wherein determining positions comprises computing positions of the one or more devices based on signals received at each of the plurality of known positions.

7. The method of claim 6, wherein correlating comprises correlating the protocol activity data derived from signals detected at the one or more known positions with the positions of the one or more devices.

8. The method of claim 1, wherein generating activity data further comprises generating spectrum activity data, wherein the spectrum activity data represents one or more of time, frequency and power characteristics of radio frequency energy received in at least a portion of the frequency band.

9. The method of claim 8, wherein generating spectrum activity data comprises generating over a time interval data for one or more of:

average power, maximum power, duty cycle, pulses per second and average pulse duration.

10. The method of claim 8, and further comprising detecting radio frequency energy in the frequency band at the one or more devices in the space, and wherein the step of generating the spectrum activity data is based upon the radio frequency energy detected at the one or more devices.

11. The method of claim 10, wherein correlating comprises correlating the spectrum activity data derived from radio frequency energy detected at the one or more devices with positions of the one or more devices.

12. The method of claim 8, wherein generating spectrum activity data is based upon radio frequency energy received at the one or more plurality of known positions.

13. The method of claim 8, wherein displaying comprises displaying the spectrum activity data on a map at positions in the space associated with the occurrence of the radio frequency energy that led to generation of that spectrum activity data.

14. The method of claim 1, wherein displaying comprises selecting a position on a grid on said map to display the protocol activity data for that position or for a nearby position for which data is available.

15. The method of claim 1, and further comprising storing the protocol activity data correlated with location;

and selecting a time basis for display of said protocol activity data, wherein said time basis includes a current time or a specified time in the past.

16. The method of claim 15, and further comprising providing user interface commands for one or more of playback, fast forward and rewind of said protocol activity data.

17. The method of claim 15, wherein displaying comprising displaying the protocol activity data in a plot with respect to time.

18. A method for monitoring wireless activity in a radio frequency band, comprising:

a. receiving radio frequency energy at each of a plurality of known positions in a space;

b. determining positions in the space of one or more devices emitting radio frequency energy in the space from the received radio frequency energy at the plurality of known positions;

c. detecting signals occurring according to a communication protocol at the plurality of known positions from the one or more devices in the space that operate according to the communication protocol;

d. wherein determining positions comprises computing positions of the one or more devices based on signals received at each of the plurality of known positions;

e. generating protocol activity data representing characteristics of received radio frequency energy in the space, wherein the protocol activity data represents characteristics of signals transmitted according to a communication protocol in the frequency band, wherein the protocol activity data is generated based upon the signals detected at the one or more devices;

f. correlating the protocol activity data with the positions in the space that are associated with provocation of the protocol activity data;

g. displaying the activity data on a map at positions in the space associated with the occurrence of the signals that led to generation of the protocol activity data; and

h. tracking movement of the one or more devices through the space.

19. A system comprising:

a. a plurality of sensor devices, each at a corresponding known position in a space, each sensor device receiving radio frequency energy at their corresponding known position;

b. a computing device coupled to the plurality of sensor devices, wherein the computing device;

i. determines positions in the space of one or more devices emitting radio frequency energy in the space from the radio frequency energy received by the sensor devices at the known positions;

ii. generates activity data comprising protocol activity data and spectrum activity data from the received radio frequency energy, wherein the protocol activity data represents characteristics of signals transmitted according to a communication protocol in a frequency band and wherein the spectrum activity data represents one or more of time, frequency and power characteristics of radio frequency energy received in at least a portion of the frequency band;

iii. correlates the activity data representing characteristics of received radio frequency energy with positions in the space associated with provocation of the activity data; and

iv. generates data for displaying the activity data on a map at positions in the space associated with the occurrence of the signals that led to generation of the activity data.

20. The system of claim 19, wherein the one or more devices operate in the frequency band according to a communication protocol, and the one or more devices generates the data from the radio frequency energy they receive, and wherein the devices send the data to the computing device.

21. The system of claim 20, wherein the one or more devices generate protocol activity data from the received radio frequency energy, wherein the protocol activity data represents characteristics of signals transmitted according to a communication protocol in the shared frequency band.

22. The system of claim 20, wherein the one or more devices generate spectrum activity data from the received radio frequency energy, wherein the spectrum activity data represents one or more of time, frequency and power characteristics of radio frequency energy received in at least a portion of the frequency band.

23. The system of claim 20, wherein the computing device computes the positions of the one or more devices from data pertaining to signals received at the one or more sensor devices from the one or more devices.

24. The system of claim 19, wherein the computing device generates data for displaying by processing a selection of a position on a grid on said map to display activity data for that position or for a nearby position for which data is available.

25. A method for monitoring wireless activity in a radio frequency band, comprising:

a. computing positions in a space of one or more devices emitting radio frequency energy in the space from radio frequency energy received at a plurality of known positions;

b. correlating spectrum activity data representing characteristics of received radio frequency energy in the space with positions in the space that are associated with provocation of the spectrum activity data, wherein the spectrum activity data represents one or more of time, frequency and power characteristics of radio frequency energy received in at least a portion of the frequency band; and

c. displaying the spectrum activity data on a map at positions in the space associated with the occurrence of the radio frequency energy that led to generation of the spectrum activity data.

26. The method of claim 25, wherein correlating further comprises correlating protocol activity data derived from the received radio frequency energy with positions in the space that are associated with provocation of the protocol activity data, wherein the protocol activity data represents characteristics of signals transmitted according to a communication protocol in the frequency band.

27. The method of claim 26, wherein displaying further comprises displaying said protocol data on the map at positions in the space associated with the occurrence of the signals that led to the generation of the protocol data.

28. The method of claim 26, wherein correlating comprises correlating data including one or more of:

average data rate, number of packet resends and number of devices operating occurring to the communication protocol.

29. The method of claim 25, wherein correlating comprises correlating spectrum activity data including one or more of:

average power, maximum power, duty cycle, pulses per second and average pulse duration.

30. The method of claim 25, wherein displaying comprises selecting a position on a grid on said map to display activity data for that position or for a nearby position for which data is available.

31. The method of claim 30, wherein displaying comprises clicking a cell on said grid on said map to display activity data for that cell or for a nearby cell for which data is available.

32. The method of claim 25, and further comprising storing spectrum activity data correlated with location;

and selecting a time basis for display of said spectrum activity data, wherein said time basis includes a current time or a specified time in the past.

33. The method of claim 32, and further comprising providing user interface commands for one or more of playback, fast forward and rewind of said spectrum activity data.

34. The method of claim 32, wherein displaying comprising displaying the spectrum activity data in a plot with respect to time.

35. The method of claim 25, wherein correlating comprises correlating spectrum activity data that represents time, frequency and power characteristics of radio frequency energy received in at least a portion of the frequency band.

36. A method for monitoring wireless activity in a radio frequency band, comprising:

a. receiving radio frequency energy at each of a plurality of known positions in a space;

b. determining positions in the space of one or more devices emitting radio frequency energy in the space from the received radio frequency energy at the plurality of known positions;

c. generating spectrum activity data representing time, frequency and power characteristics of radio frequency energy received in at least a portion of the frequency band from the received radio frequency energy;

d. correlating the spectrum activity data representing characteristics of received radio frequency energy in the space with positions in the space that are associated with provocation of the spectrum activity data; and

e. displaying the spectrum activity data on a map at positions in the space associated with the occurrence of the radio frequency energy that led to generation of the spectrum activity data.

37. The method of claim 36, and further comprising generating, as part of said spectrum activity data, average power, maximum power, duty cycle, pulses per second and average pulse duration, associated with radio frequency energy received in the frequency band.

38. The method of claim 36, wherein displaying comprises selecting a position on a grid on said map to display the spectrum activity data for that position or for a nearby position for which data is available.

39. The method of claim 36, and further comprising providing user interface commands for playback, fast forward and rewind of said spectrum activity data.

40. The method of claim 36, wherein displaying comprising displaying the spectrum activity data in a plot with respect to time.