Supression of unwanted signal elements by sinusoidal amplitude windowing

• US 8,085,886 B2
• Filed: 11/19/2004
• Issued: 12/27/2011
• Est. Priority Date: 11/21/2003
• Status: Active Grant

• Current Assignee: BAE Systems Plc
• Original Assignee: BAE Systems Plc
• Inventors: Richardson, Michael Richard
• Primary Examiner(s): Liu, Shuwang
• Assistant Examiner(s): MCKIE, GINA M
• Application Number:
  US10/521,745
• Publication Number:
  US 20050262178A1
• Time in Patent Office: 2,594 Days
• Field of Search: 375/260, 375/355, 375/347
• US Class Current: 375/346
• CPC Class Codes: H01Q 3/267 Phased-array testing or checking devices
• CPC Class Codes: H04B 17/10 of transmitters
• CPC Class Codes: H04B 7/0837 using pre-detection combining H04B7/0868 takes precedence
• CPC Class Codes: H04J 3/0608 Detectors therefor, e.g. correlators, state machines
• CPC Class Codes: H04L 27/2624 by soft clipping
• CPC Class Codes: H04L 7/08 the synchronisation signals recurring cyclically

Abstract

A method is provided for processing a signal containing regular or quasi-regular elements of unwanted signal. The method establishes timing characteristics of the unwanted signal elements in a portion of the signal. A time domain window function is generated using the established timing characteristics. The generated window function is applied to the signal portion to selectively reduce the amplitude of the unwanted signal elements relative to the amplitude of other elements of the signal.

Claims

1. A method for digitally processing a received signal containing regular bursts of unwanted signal within the received signal, the method comprising the steps of:

(i) establishing timing characteristics of the regular bursts of unwanted signal to establish their positions in a portion of said received signal;

(ii) generating a time domain sinusoidal function using said established timing characteristics, said time domain sinusoidal function having a zero crossing coinciding with the position of each of the regular bursts of unwanted signal; and

(iii) applying the time domain generated sinusoidal function to said signal portion to selectively reduce the amplitude of said regular bursts of unwanted signal relative to other elements of said received signal in an output signal.

2. A method according to claim 1, further comprising the steps of:

(iv) applying a Fourier transform to the output signal to provide a transformed signal; and

(v) applying an algorithm to restore a shape of peaks in the transformed signal to an approximation of their form in absence of said regular bursts of unwanted signal.