Removal of modulated tonal interference

Patent metadata

Field	Value
Publication number	US-9419677-B2
Application number	US-31709208-A
Country	US
Kind code	B2
Filing date	Dec 19, 2008
Priority date	Dec 19, 2008
Publication date	Aug 16, 2016
Grant date	Aug 16, 2016

Abstract

In some embodiments a phase between a periodic spreading signal and an effective spreading signal modulating an interfering harmonic is determined, an amplitude of the interfering harmonic is estimated, and the interfering harmonic is canceled from a received signal. Other embodiments are described and claimed.

First claim

What is claimed is:

1. A method comprising:
determining, by a phase estimator, a phase between a periodic spreading signal and an effective spreading signal, wherein the periodic spreading signal comprises a frequency variation of a harmonic of a reference clock signal, and wherein the effective spreading signal comprises a variation of an interfering harmonic in a received signal;
estimating, by an amplitude estimator, an amplitude of the interfering harmonic; and
canceling, by a tone suppressor, the interfering harmonic from the received signal based on the amplitude of the interfering harmonic and the phase between the periodic spreading signal and the effective spreading signal.

2. The method of claim 1 , wherein the determining is performed using direct measurement of the periodic spreading signal.

3. The method of claim 1 , further comprising generating a digital reference signal, wherein the determining is performed using the generated digital reference signal.

4. The method of claim 1 , further comprising estimating a mean squared error, wherein the determining is performed using the estimated mean squared error.

5. The method of claim 1 , further comprising determining a form of the periodic spreading signal.

6. The method of claim 1 , wherein the estimating is performed independently of the determining.

7. The method of claim 1 , wherein the estimating is performed jointly with the determining.

8. The method of claim 1 , wherein the canceling is performed using subtractive canceling techniques, adaptive cancellation, adaptive filtering, and/or time-varying narrowband filtering.

9. The method of claim 1 , wherein the canceling removes only a true time varying narrow interferer signal from the received signal.

10. An apparatus comprising:
a phase estimator to determine a phase between a periodic spreading signal and an effective spreading signal, wherein the periodic spreading signal comprises a frequency variation of a harmonic of a reference clock signal, and wherein the effective spreading signal comprises a variation of an interfering harmonic in a received signal;
an amplitude estimator to estimate an amplitude of the interfering harmonic; and
a tone suppressor to cancel the interfering harmonic from the received signal based on the amplitude of the interfering harmonic and the phase between the periodic spreading signal and the effective spreading signal.

11. The apparatus of claim 10 , wherein the phase estimator is to determine the phase using direct measurement of the periodic spreading signal.

12. The apparatus of claim 10 , wherein the phase estimator is further to generate a digital reference signal and to determine the phase using the generated digital reference signal.

13. The apparatus of claim 10 , wherein the phase estimator is further to estimate a mean squared error and to determine the phase using the estimated mean squared error.

14. The apparatus of claim 10 , wherein the phase estimator is further to determine a form of the periodic spreading signal.

15. The apparatus of claim 10 , wherein the amplitude estimator is to estimate the amplitude independently of the phase estimator to determine the phase.

16. The apparatus of claim 10 , wherein the amplitude estimator is to estimate the amplitude jointly with the phase estimator to determine the phase.

17. The apparatus of claim 10 , wherein the amplitude estimator is an adaptive filter.

18. The apparatus of claim 10 , wherein the tone suppressor is to use subtractive canceling techniques, adaptive cancellation, adaptive filtering, and/or time-varying narrowband filtering.

19. The apparatus of claim 10 , wherein the tone suppressor is to remove only a true time varying narrow interferer signal from the received signal.

20. A system comprising:
a computing platform;
a radio coupled to the computing platform to transmit and receive radio frequency signals; and
an interference suppressor to track small deviations in the fundamental frequency of one or more clocks interfering with the radio frequency signals and to cancel or attenuate clock harmonic interference, the interference suppressor comprising:
a phase estimator to determine a phase between a periodic spreading signal and an effective spreading signal, wherein the periodic spreading signal comprises a frequency variation of a harmonic of a reference clock signal, and wherein the effective spreading signal comprises a variation of an interfering harmonic in a received signal;
an amplitude estimator to estimate an amplitude of the interfering harmonic; and
a tone suppressor to canceling the interfering harmonic from the received signal based on the amplitude of the interfering harmonic and the phase between the periodic spreading signal and the effective spreading signal.

21. The system of claim 20 , wherein the phase estimator is to determine the phase using direct measurement of the periodic spreading signal.

22. The system of claim 20 , wherein the phase estimator is further to generate a digital reference signal and to determine the phase using the generated digital reference signal.

23. The system of claim 20 , wherein the phase estimator is further to estimate a mean squared error and to determine the phase using the estimated mean squared error.

24. The system of claim 20 , wherein the phase estimator is further to determine a form of the periodic spreading signal.

25. The system of claim 20 , wherein the amplitude estimator is to estimate the amplitude independently of the phase estimator to determine the phase.

26. The system of claim 20 , wherein the amplitude estimator is to estimate the amplitude jointly with the phase estimator to determine the phase.

27. The system of claim 20 , wherein the amplitude estimator is an adaptive filter.

28. The system of claim 20 , wherein the tone suppressor is to use subtractive canceling techniques, adaptive cancellation, adaptive filtering, and/or time-varying narrowband filtering.

29. The system of claim 20 , wherein the tone suppressor is to remove only a true time varying narrow interferer signal from the received signal.

Assignees

• Deisher Michael E
• Tinsley Keith R
• Intel Corp

Inventors

• Deisher Michael E
• Tinsley Keith R

Classifications

• H04B1/7097 Primary

  Interference-related aspects · CPC title

• H04B2215/067

  by modulation dispersion · CPC title

• H04B15/02

  Reducing interference from electric apparatus by means located at or near the interfering apparatus · CPC title

• H04B1/10

  Means associated with receiver for limiting or suppressing noise or interference · CPC title

• H04B15/04 Primary

  the interference being caused by substantially sinusoidal oscillations, e.g. in a receiver or in a tape-recorder · CPC title