Methods and apparatus for digital jammer detection

Abstract

Methods and apparatus for digital jammer detection. In an aspect, a method is provided for detecting a jammer in a received waveform. The method includes filtering the received waveform to produce a filtered waveform and subtracting the filtered waveform from the received waveform to produce a difference waveform. The method also includes determining a power differential associated with the difference waveform, and detecting the jammer if the power differential exceeds a selected threshold. In an aspect, an apparatus is provided that includes a filter configured to filter the received waveform to produce a filtered waveform and combining logic configured to subtract the filtered waveform from the received waveform to produce a difference waveform. The apparatus also includes power determination logic configured to determine a power differential associated with the difference waveform, and decision logic configured to detect the jammer if the power differential exceeds a selected threshold.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing aspects described herein will become more readily apparent by reference to the following description when taken in conjunction with the accompanying drawings wherein:

FIG. 1 shows a network that comprises an aspect of a detection system;

FIG. 2 shows a receiver for use in aspects of a detection system;

FIG. 3 shows detection logic for use in aspects of a detection system;

FIG. 4 shows a method for use in aspects of a detection system;

FIG. 5 shows a graph that illustrates the performance of an aspect of a detection system; and

FIG. 6 shows detection logic for use in aspects of a detection system.

Claims

1. A method for detecting a jammer in a received waveform, the method comprising: filtering the received waveform to produce a filtered waveform;subtracting the filtered waveform from the received waveform to produce a difference waveform;determining a power differential associated with the difference waveform; anddetecting the jammer if the power differential exceeds a selected threshold.

2. The method of claim 1, further comprising filtering the power differential to form a moving average of the power differential.

3. The method of claim 2, wherein said filtering the power differential comprises filtering the power differential using an infinite impulse response (IIR) filter.

4. The method of claim 2, wherein said filtering the power differential comprises filtering the power differential using a finite impulse response (FIR) filter.

5. The method of claim 1, wherein said determining the power differential comprises summing In-phase (IDIF) and Quadrature (QDIF) difference waveforms.

6. The method of claim 1, further comprising increasing linearity performance if the jammer is detected.

7. The method of claim 6, wherein said increasing comprises adjusting a bias condition.

8. The method of claim 1, further comprising generating the selected threshold based on demodulator performance.

9. The method of claim 1, further comprising digitizing a down converted waveform to produce the received waveform.

10. An apparatus for detecting a jammer in a received waveform, the apparatus comprising: a filter configured to filter the received waveform to produce a filtered waveform;combining logic configured to subtract the filtered waveform from the received waveform to produce a difference waveform;power determination logic configured to determine a power differential associated with the difference waveform; anddecision logic configured to detect the jammer if the power differential exceeds a selected threshold.

11. The apparatus of claim 10, further comprising a second filter configured to filter the power differential to form a moving average of the power differential.

12. The apparatus of claim 11, wherein said second filter comprises an infinite impulse response (IIR) filter.

13. The apparatus of claim 11, wherein said second filter comprises a finite impulse response (FIR) filter.

14. The apparatus of claim 10, wherein said power determination logic operates to sum In-phase (IDIF) and Quadrature (QDIF) difference waveforms.

15. The apparatus of claim 10, wherein the decision logic further comprises logic configured to increase linearity performance if the jammer is detected.

16. The apparatus of claim 15, wherein said logic configured to increase linearity performance operates to adjust a bias condition.

17. The apparatus of claim 10, further comprising logic configured to generate the selected threshold based on demodulator performance.

18. The apparatus of claim 10, further comprising an analog to digital (A/D) converter configured to digitize a down converted waveform to produce the received waveform.

19. An apparatus for detecting a jammer in a received waveform, the apparatus comprising: means for filtering the received waveform to produce a filtered waveform;means for subtracting the filtered waveform from the received waveform to produce a difference waveform;means for determining a power differential associated with the difference waveform; andmeans for detecting the jammer if the power differential exceeds a selected threshold.

20. The apparatus of claim 19, further comprising means for filtering the power differential to form a moving average of the power differential.

21. The apparatus of claim 20, wherein said means for filtering the power differential comprises means for filtering the power differential using an infinite impulse response (IIR) filter.

22. The apparatus of claim 20, wherein said means for filtering the power differential comprises means for filtering the power differential using a finite impulse response (FIR) filter.

23. The apparatus of claim 19, wherein said means for determining the power differential comprise means for summing In-phase (IDIF) and Quadrature (QDIF) difference waveforms.

24. The apparatus of claim 19, further comprising means for increasing linearity performance if the jammer is detected.

25. The apparatus of claim 24, wherein said means for increasing comprises means for adjusting a bias condition.

26. The apparatus of claim 19, further comprising means for generating the selected threshold based on demodulator performance.

27. The apparatus of claim 19, further comprising means for digitizing a down converted waveform to produce the received waveform.

28. A computer-readable medium having a computer program comprising instructions, which when executed by at least one processor, operate to detect a jammer in a received waveform, the computer program comprising: instructions for filtering the received waveform to produce a filtered waveform;instructions for subtracting the filtered waveform from the received waveform to produce a difference waveform;instructions for determining a power differential associated with the difference waveform; andinstructions for detecting the jammer if the power differential exceeds a selected threshold.

29. The computer program of claim 28, further comprising instructions for filtering the power differential to form a moving average of the power differential.

30. The computer program of claim 29, wherein said instructions for filtering the power differential comprise instructions for filtering the power differential using an infinite impulse response (IIR) filter.

31. The computer program of claim 29, wherein said instructions for filtering the power differential comprise instructions for filtering the power differential using a finite impulse response (FIR) filter.

32. The computer program of claim 28, wherein said instructions for determining the power differential comprise instructions for summing In-phase (IDIF) and Quadrature (QDIF) difference waveforms.

33. The computer program of claim 28, further comprising instructions for increasing linearity performance if the jammer is detected.

34. The computer program of claim 33, wherein said instructions for increasing comprise instructions for adjusting a bias condition.

35. The computer program of claim 28, further comprising instructions for generating the selected threshold based on demodulator performance.

36. The computer program of claim 28, further comprising instructions for digitizing a down converted waveform to produce the received waveform.

37. At least one processor configured to perform a method for detecting a jammer in a received waveform, the method comprising: filtering the received waveform to produce a filtered waveform;subtracting the filtered waveform from the received waveform to produce a difference waveform;determining a power differential associated with the difference waveform; anddetecting the jammer if the power differential exceeds a selected threshold.

38. The method of claim 37, further comprising filtering the power differential to form a moving average of the power differential.

39. The method of claim 38, wherein said filtering the power differential comprises filtering the power differential using an infinite impulse response (IIR) filter.

40. The method of claim 38, wherein said filtering the power differential comprises filtering the power differential using a finite impulse response (FIR) filter.

41. The method of claim 37, wherein said determining the power differential comprises summing In-phase (IDIF) and Quadrature (QDIF) difference waveforms.

42. The method of claim 37, further comprising increasing linearity performance if the jammer is detected.

43. The method of claim 42, wherein said increasing comprises adjusting a bias condition.

44. The method of claim 37, further comprising generating the selected threshold based on demodulator performance.

45. The method of claim 37, further comprising digitizing a down converted waveform to produce the received waveform.