Systems and methods for detecting radar

• US 7,623,060 B1
• Filed: 06/25/2007
• Issued: 11/24/2009
• Est. Priority Date: 06/29/2006
• Status: Expired due to Fees

• Current Assignee: Marvell International Limited (Marvell Technology Group Limited)
• Original Assignee: Marvell International Limited (Marvell Technology Group Limited)
• Inventors: Chhabra, Kapil, Nallapureddy, Bhaskar V.
• Primary Examiner(s): Tarcza; Thomas H
• Assistant Examiner(s): Barker; Matthew M
• Application Number:
  US11/821,719
• Time in Patent Office: 883 Days
• Field of Search: 342/20
• US Class Current: 342/20
• CPC Class Codes: G01S 7/021 Auxiliary means for detecting or identifying radar signals or the like, e.g. radar jamming signals

Abstract

A system includes a first-in first-out (FIFO) module, a polling module, a data extraction module, and a control module. The FIFO module receives records having dynamic frequency selection (DFS) information generated based on pulses received and generates a control signal for every N of the records received, where N is an integer greater than or equal to 1. The polling module selectively polls the FIFO module and reads M of the records received by the FIFO module, where M is an integer greater than or equal to 1 and less than N. The data extraction module extracts the DFS information from the N records when the control signal is received and selectively extracts the DFS information from the M records. The control module determines whether the pulses are a type of radar based on the DFS information extracted from at least N of the (N+M) of the records.

Claims

1. A system, comprising:

a first-in first-out (FIFO) module that receives records having dynamic frequency selection (DFS) information generated based on pulses received, and that generates a control signal for every N of said records received, where N is an integer greater than 1;

a polling module that selectively polls said FIFO module, and that reads M of said records received by said FIFO module, where M is an integer greater than or equal to 1 and less than N;

a data extraction module that extracts said DFS information from said N of said records when said control signal is received, and that selectively extracts said DFS information from said M of said records; and

a control module that determines whether said pulses are a type of radar based on said DFS information extracted from at least N of (N+M) of said records.

2. The system of claim 1 wherein said DFS information comprises pulse widths and pulse repetition rates of said pulses, signal strength of radio frequency (RF) signals in said pulses, and whether said pulses are one of a tone type and a chirp type radar pulses.

3. The system of claim 1 wherein said polling module polls said FIFO module when said DFS information extracted from a predetermined number of records out of said N of said records indicates that said pulses are not radar pulses.

4. The system of claim 1 further comprising a buffer module that stores said DFS information extracted by said data extraction module.

5. The system of claim 1 wherein said pulses are received from at least one burst of radar.

6. The system of claim 5 wherein said control module determines that said pulses are a type of tone radar when:

said DFS information extracted from each of said at least N of said (N+M) of said records includes information that a corresponding one of said pulses is a tone radar pulse;

an average of pulse widths in said DFS information extracted from each of said at least N of said (N+M) of said records approximately matches a pulse width of a predetermined type of tone radar;

a difference between a maximum and a minimum of said pulse widths is less than a predetermined threshold; and

pulse repetition intervals in said DFS information extracted from a predetermined number of said at least N of said (N+M) of said records approximately match a pulse repetition interval of said predetermined type of tone radar.

7. The system of claim 5 wherein said control module determines that said pulses are a type of chirp radar when:

said DFS information extracted from each of said at least N of said (N+M) of said records includes information that a corresponding one of said pulses is a chirp radar pulse;

pulse widths in said DFS information extracted from said at least N of said (N+M) of said records approximately match pulse widths of a predetermined type of chirp radar; and

pulse repetition intervals in said DFS information extracted from a predetermined number of said at least N of said (N+M) of said records approximately match pulse repetition intervals of said predetermined type of chirp radar.

8. The system of claim 1 wherein said control module determines whether said pulses are a type of one of a tone radar and a chirp radar based on pulse widths in said DFS information extracted from at least N of said records when said pulses are received from at least one burst of radar and when said pulses are separated by at least one data packet.

9. The system of claim 8 wherein said control module determines that said pulses are a type of tone radar when said pulse widths match a pulse width of a predetermined type of tone radar and wherein said control module determines that said pulses are a type of chirp radar when said pulse widths match pulse widths of a predetermined type of chirp radar.

10. The system of claim 1 wherein said pulses comprise radio frequency (RF) signals and said DFS information includes a number of zero-crossings of said RF signals per bin for a plurality of bins, where said bin is a time period greater than or equal to a smallest of pulse widths of predetermined types of radar pulses.

11. The system of claim 10 wherein said control module determines that said pulses are tone type radar pulses when a difference between maximum and minimum values of said number of zero-crossings is less than a predetermined threshold.

12. The system of claim 10 wherein said control module determines that said pulses are chirp type radar pulses when:

differences between said number of zero-crossings in adjacent bins are greater than a first predetermined threshold; and

a rate of change of said number of zero-crossings in successive bins is less than a second predetermined threshold.

13. A medium access controller (MAC) comprising the system of claim 1 and further comprising a physical layer module (PHY) that communicates said records to the MAC.

14. A wireless network device comprising the MAC of claim 13 and further comprising at least one antenna that receives said pulses and that communicates said pulses to said PHY.

15. A radar detection device comprising the system of claim 1.

16. A method, comprising:

receiving records having dynamic frequency selection (DFS) information generated based on pulses received in a first-in first-out (FIFO) module;

generating a control signal for every N of said records received, where N is an integer greater than 1;

selectively polling said FIFO module;

reading M of said records received by said FIFO module, where M is an integer greater than or equal to 1 and less than N;

extracting said DFS information from said N of said records when said control signal is received;

selectively extracting said DFS information from said M of said records; and

determining whether said pulses are a type of radar based on said DFS information extracted from at least N of said (N+M) of said records.

17. The method of claim 16 further comprising receiving said records having said DFS information that includes pulse widths and pulse repetition rates of said pulses, signal strength of radio frequency (RF) signals in said pulses, and whether said pulses are one of a tone type and a chirp type radar pulses.

18. The method of claim 16 further comprising polling said FIFO module when said DFS information extracted from a predetermined number of records out of said N of said records indicates that said pulses are not radar pulses.

19. The method of claim 16 further comprising storing said DFS information extracted by said data extraction module.

20. The method of claim 16 further comprising receiving said pulses from at least one burst of radar.

21. The method of claim 20 further comprising determining that said pulses are a type of tone radar when:

said DFS information extracted from each of said at least N of said (N+M) of said records includes information that a corresponding one of said pulses is a tone radar pulse;

an average of pulse widths in said DFS information extracted from each of said at least N of said (N+M) of said records approximately matches a pulse width of a predetermined type of tone radar;

a difference between a maximum and a minimum of said pulse widths is less than a predetermined threshold; and

pulse repetition intervals in said DFS information extracted from a predetermined number of said at least N of said (N+M) of said records approximately match a pulse repetition interval of said predetermined type of tone radar.

22. The method of claim 20 further comprising determining that said pulses are a type of chirp radar when:

said DFS information extracted from each of said at least N of said (N+M) of said records includes information that a corresponding one of said pulses is a chirp radar pulse;

pulse widths in said DFS information extracted from said at least N of said (N+M) of said records approximately match pulse widths of a predetermined type of chirp radar; and

pulse repetition intervals in said DFS information extracted from a predetermined number of said at least N of said (N+M) of said records approximately match pulse repetition intervals of said predetermined type of chirp radar.

23. The method of claim 16 further comprising determining whether said pulses are a type of one of a tone radar and a chirp radar based on pulse widths in said DFS information extracted from at least N of said records when said pulses are received from at least one burst of radar and when said pulses are separated by at least one data packet.

24. The method of claim 23 further comprising determining that said pulses are a type of tone radar when said pulse widths match a pulse width of a predetermined type of tone radar and determining that said pulses are a type of chirp radar when said pulse widths match pulse widths of a predetermined type of chirp radar.

25. The method of claim 16 further comprises receiving said records when said pulses include radio frequency (RF) signals and wherein said DFS information includes a number of zero-crossings of said RF signals per bin for a plurality of bins, where said bin is a time period greater than or equal to a smallest of pulse widths of predetermined types of radar pulses.

26. The method of claim 25 further comprising determining that said pulses are tone type radar pulses when a difference between maximum and minimum values of said number of zero-crossings is less than a predetermined threshold.

27. The method of claim 25 further comprises determining that said pulses are chirp type radar pulses when:

differences between said number of zero-crossings in adjacent bins are greater than a first predetermined threshold; and

a rate of change of said number of zero-crossings in successive bins is less than a second predetermined threshold.

28. The method of claim 16 further comprising communicating between a physical layer module (PHY) and a medium access controller (MAC) and communicating said records to said MAC.

29. The method of claim 28 further comprising receiving said pulses via at least one antenna in a wireless network device and communicating said pulses to said PHY.

30. The method of claim 16 further comprising determining whether said pulses include radar when said pulses are received by a radar detection device.

31. A system, comprising:

first-in first-out (FIFO) means for

receiving records having dynamic frequency selection (DFS) information generated based on pulses received, and

generating a control signal for every N of said records received, where N is an integer greater than 1;

polling means for selectively polling said FIFO means and reading M of said records received by said FIFO means, where M is an integer greater than or equal to 1 and less than N;

data extraction means for

extracting said DFS information from said N of said records when said control signal is received, and

selectively extracting said DFS information from said M of said records; and

control means for determining whether said pulses are a type of radar based on said DFS information extracted from at least N of (N+M) of said records.

32. The system of claim 31 wherein said DFS information comprises pulse widths and pulse repetition rates of said pulses, signal strength of radio frequency (RF) signals in said pulses, and whether said pulses are one of a tone type and a chirp type radar pulses.

33. The system of claim 31 wherein said polling means polls said FIFO means when said DFS information extracted from a predetermined number of records out of said N of said records indicates that said pulses are not radar pulses.

34. The system of claim 31 further comprising buffer means for storing said DFS information extracted by said data extraction means.

35. The system of claim 31 wherein said pulses are received from at least one burst of radar.

36. The system of claim 35 wherein said control means determines that said pulses are a type of tone radar when:

said DFS information extracted from each of said at least N of said (N+M) of said records includes information that a corresponding one of said pulses is a tone radar pulse;

an average of pulse widths in said DFS information extracted from each of said at least N of said (N+M) of said records approximately matches a pulse width of a predetermined type of tone radar;

a difference between a maximum and a minimum of said pulse widths is less than a predetermined threshold; and

pulse repetition intervals in said DFS information extracted from a predetermined number of said at least N of said (N+M) of said records approximately match a pulse repetition interval of said predetermined type of tone radar.

37. The system of claim 35 wherein said control means determines that said pulses are a type of chirp radar when:

said DFS information extracted from each of said at least N of said (N+M) of said records includes information that a corresponding one of said pulses is a chirp radar pulse;

pulse widths in said DFS information extracted from said at least N of said (N+M) of said records approximately match pulse widths of a predetermined type of chirp radar; and

pulse repetition intervals in said DFS information extracted from a predetermined number of said at least N of said (N+M) of said records approximately match pulse repetition intervals of said predetermined type of chirp radar.

38. The system of claim 31 wherein said control means determines whether said pulses are a type of one of a tone radar and a chirp radar based on pulse widths in said DFS information extracted from at least N of said records when said pulses are received from at least one burst of radar and when said pulses are separated by at least one data packet.

39. The system of claim 38 wherein said control means determines that said pulses are a type of tone radar when said pulse widths match a pulse width of a predetermined type of tone radar and wherein said control means determines that said pulses are a type of chirp radar when said pulse widths match pulse widths of a predetermined type of chirp radar.

40. The system of claim 31 wherein said pulses comprise radio frequency (RF) signals and said DFS information includes a number of zero-crossings of said RF signals per bin for a plurality of bins, where said bin is a time period greater than or equal to a smallest of pulse widths of predetermined types of radar pulses.

41. The system of claim 40 wherein said control means determines that said pulses are tone type radar pulses when a difference between maximum and minimum values of said number of zero-crossings is less than a predetermined threshold.

42. The system of claim 40 wherein said control means determines that said pulses are chirp type radar pulses when:

differences between said number of zero-crossings in adjacent bins are greater than a first predetermined threshold; and

a rate of change of said number of zero-crossings in successive bins is less than a second predetermined threshold.

43. A medium access controller (MAC) comprising the system of claim 31 and further comprising physical layer means (PHY) for communicating said records to the MAC.

44. A wireless network device comprising the MAC of claim 43 and further comprising at least one antenna means for receiving said pulses and communicating said pulses to said PHY means.

45. A radar detection device comprising the system of claim 31.