Method of selectively reducing spectral components in a wideband radio frequency signal
First Claim
Patent Images
1. A method of selectively reducing a bandwidth of spectral components of a wideband multi-carrier analog radio frequency (RF) signal at an input to an analog-to-digital (A/D) converter having digitized samples as an output, such method comprising the steps of:
- analyzing the digital samples of the carriers for relatively large spectral peaks; and
applying a notch filter to the input of the analog-to-digital (A/D) converter to reduce the relatively large spectral peaks to a threshold value, whereby the notch filter is applied to selected carrier having large spectral peaks exceeding the threshold value and not to carriers having spectral peaks below the threshold value.
0 Assignments
0 Petitions
Accused Products
Abstract
A method of selectively reducing a magnitude of spectral components of a wideband analog radio frequency (RF) signal at an input to an analog-to-digital (A/D) converter is provided. The method includes the steps of digitizing the input to the A/D converter, analyzing the digitized inputs for relatively large spectral peaks, and notch filtering the relatively large peaks to a threshold value.
-
Citations
21 Claims
-
1. A method of selectively reducing a bandwidth of spectral components of a wideband multi-carrier analog radio frequency (RF) signal at an input to an analog-to-digital (A/D) converter having digitized samples as an output, such method comprising the steps of:
-
analyzing the digital samples of the carriers for relatively large spectral peaks; and applying a notch filter to the input of the analog-to-digital (A/D) converter to reduce the relatively large spectral peaks to a threshold value, whereby the notch filter is applied to selected carrier having large spectral peaks exceeding the threshold value and not to carriers having spectral peaks below the threshold value. - View Dependent Claims (2, 3, 4, 5, 6)
-
-
7. A method of selectively reducing a magnitude of spectral components of a wideband multi-carrier analog radio frequency (RF) signal at an input to an analog-to-digital (A/D) converter having digitized samples as an output, such method comprising the steps of:
-
a) analyzing the digital samples of the carriers for relatively large spectral peaks; b) calculating a notch depth and bandwidth required to reduce the relatively large spectral peaks to at least a threshold value; c) selecting notch filter coefficients, based on the calculated notch depth and bandwidth,; d) applying a notch filter, based on the selected notch filter coefficients, to the carriers analyzed to have relatively large spectral peaks to reduce the relatively large spectral peaks to at least the threshold value; and e) repeating steps (a) through (d). - View Dependent Claims (8, 9, 10, 11, 12)
-
-
13. A method of selectively reducing a magnitude of spectral components of a wideband multi-carrier analog signal at an input to an analog-to-digital (A/D) converter having digitized samples as an output, such method comprising the steps of:
-
a) characterizing the digital samples using a fast fourier transform (FFT); b) comparing the characterized digital samples with a threshold to identify spectra of the carriers having a magnitude of a spectral peak exceeding a threshold; c) calculating a notch depth and bandwidth to reduce the identified spectral peak to at least the threshold; d) selectively notch filtering the spectral peaks to at least the threshold, whereby notch filtering is applied to the spectral peaks identified as having a magnitude exceeding the threshold; and e) repeating steps (a) through (d). - View Dependent Claims (14, 15)
-
-
16. A method of selectively reducing a magnitude of spectral components of a wideband multi-carrier analog radio frequency (RF) signal at an input to an analog-to-digital (A/D) converter of a cellular base station, the A/D converter having digitized samples as an output, such method comprising the steps of:
-
analyzing the digital samples of the carriers for relatively large spectral peaks; and applying a notch filter to the input of the analog-to-digital (A/D) converter to reduce the relatively large spectral peaks to a threshold value, whereby the notch filter is applied to selected carriers having large spectral peaks exceeding the threshold value and not to carriers having spectral peaks below the threshold value. - View Dependent Claims (17, 18, 19, 20, 21)
-
Specification