Claims
- 1. A method of time varying filtering, comprising:
a. filtering a segment of a signal using a filter; and b. disengaging the filter in a sequence of graduated steps at the end of the segment; and c. repeating steps a and b until all segments have been filtered.
- 2. The method of claim 1, where a given filter is disengaged by changing the coefficients from their regular values for the filter to values reflecting a gain of unity and no phase delay.
- 3. The method of claim 2, where each filter is disengaged in a series of intermediate steps.
- 4. The method of claim 3, where in each said step the filter has a different set of coefficients.
- 5. The method of claim 4, where one sample from the input signal is processed during each step.
- 6. The method of claim 4, where two or more samples from the input signal are processed during each step.
- 7. A method of time varying filtering, comprising:
a. engaging a filter in a sequence of graduated steps at the beginning of a signal segment; b. filtering the segment of using the filter; and c. repeating steps a and b until all segments have been filtered.
- 8. The method of claim 7, where a given filter is engaged by changing the coefficients from values reflecting a gain of unity and no phase delay to their regular values.
- 9. The method of claim 8, where each filter is engaged in a series of intermediate steps.
- 10. The method of claim 9, where in each said step the filter has a different set of coefficients.
- 11. The method of claim 10, where one sample from the input signal is processed during each step.
- 12. The method of claim 10, where two or more samples from the input signal are processed during each step.
- 13. A method of time varying filtering, comprising:
a. engaging a filter in a sequence of graduated steps at the beginning of a signal segment; b. filtering the segment of using the filter; c. disengaging the filter in a sequence of graduated steps at the end of a signal segment; and d. repeating steps a-c until all segments have been filtered.
- 14. The method of claim 13, where a given filter is engaged by changing the coefficients from values reflecting a gain of unity and no phase delay to their regular values.
- 15. The method of claim 14, where each filter is engaged in a series of intermediate steps.
- 16. The method of claim 15, where in each said step the filter has a different set of coefficients.
- 17. The method of claim 16, where one sample from the input signal is processed during each step.
- 18. The method of claim 16, where two or more samples from the input signal are processed during each step.
- 19. An article comprising a computer readable medium having instructions stored thereon which when executed causes:
a. filtering a segment of a signal using a filter; b. disengaging the filter in a sequence of graduated steps at the end of the segment; and c. repeating steps a and b until all input signal segments have been filtered.
- 20. An article comprising a computer readable medium having instructions stored thereon which when executed causes:
a. engaging a filter in a sequence of graduated steps at the beginning of a signal segment; b. filtering the segment using the filter; and c. repeating steps a and b until all input signal segments have been filtered.
- 21. An article comprising a computer readable medium having instructions stored thereon which when executed causes:
a. filtering a segment of a signal using a filter; b. disengaging the filter in a sequence of graduated steps at the end of the segment; c. engaging a filter in a sequence of graduated steps at the beginning of the next segment of the signal; and d. repeating steps a-c until all input signal segments have been filtered.
- 22. A method, comprising:
inaudibly switching one or more filters on and/or off during processing of an input signal by:
migrating their coefficients from an original set of values to a final set of values through a series of intermediate steps.
- 23. The method of claim 22, where said filters are:
engaged by changing the coefficients to their regular values for the filter from values reflecting a gain of unity and no phase delay, and disengaged by changing the coefficients from their regular values for the filter to values reflecting a gain of unity and no phase delay.
- 24. The method of claim 23, where each filter is disengaged or disengaged, as the case may be, in a number of intermediate steps.
- 25. The method of claim 24, where in each said step the filter has a different set of coefficients.
- 26. The method of claim 25, where one sample from the input signal is processed during each step.
- 27. The method of claim 25, where two or more samples from the input signal are processed during each step.
- 28. Apparatus for time varying filtering, comprising:
a filtering processor, arranged to process a given input signal by implementing an arbitrary filter; and a coefficient calculator, arranged to calculate:
the co-efficients for the arbitrary filter; a set of new coefficients for the arbitrary filter, at which the filter is neutralized; and a series of intermediate co-efficient values between the original filter coefficients and the new coefficients.
- 29. The apparatus of claim 28, further comprising a memory to store a plurality of filtering coefficients.
- 30. The method of any of claims 1-6, or of claims 13-18, where a filter is disengaged by migrating its poles to its zeros, or its zeros to its poles.
- 31. The method of claim 30, where after the migration has been completed, the filter is removed.
- 32. The method of claim 30, where after the migration has been completed, the colocational poles and zeros are then migrated to the origin via a series of intermediate steps.
- 33. The method of claim 30, where after the migration has been completed:
the colocational poles and zeros are then migrated to the origin via a series of intermediate steps; and the filter is then removed.
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional Patent Application No. 60/317,802, filed on Sep. 7, 2001.
Provisional Applications (1)
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Number |
Date |
Country |
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60317802 |
Sep 2001 |
US |