Methods and apparatus for spectral filtering channel estimates

Details Methods and apparatus for spectral filtering channel estimates Methods and apparatus for spectral filtering channel estimates

2007-02-06

2007-02-06

Ghayour, Mohammed (Department: 2611)

Pulse or digital communications

Receivers

Interference or noise reduction

C375S340000, C375S341000

Reexamination Certificate

active

10172984

ABSTRACT:
Methods and apparatus for performing spectral filtering of channel estimates corresponding to a communications channel used to transmit a multi-tone signal are described. A channel estimate is examined to identify portions where significant multi-path interference is present. Real, as opposed to complex, low pass filters are used to perform spectral filtering on the channel estimate to produce a filtered channel estimate. Values corresponding to portions of the channel estimate determined to correspond to areas where significant multi-path interference is present are replaced with the original unfiltered channel estimate values to generate a selectively filtered channel estimate. By using unfiltered channel estimate values in areas of multi-path interference, the errors introduced in such areas by real filtering are avoided without the need to resort to complex filtering.

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