Kalman Filter-Based Architectures for Interference Excision

Abstract

This report presents a novel Kalman filtering approach to the suppression of narrowband interference from direct sequence spread spectrum communications systems. The algorithm is based on the digital phase-locked loop Kalman filter. Because the interference is assumed to be much stronger than either the signal or noise, the Kalman filter locks onto a function related to the interference. The net result is an estimate of the phase of the interference and its amplitude. The algorithm is characterized through computer simulation for the case of narrowband Gaussian noise interference. Examples of the phase- and envelope-tracking capabilities of the algorithm are presented, followed by bit error rate curves for interference bandwidths ranging from 0.5% to 5.0% of the chip rate of the spread spectrum signal. The report concludes with three adaptive architectures. -The first is suitable for constant envelope interference; the second is a more general structure; and the third incorporate a decision-feedback structure accompanied with a training sequence.

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Document Details

Document Type
Technical Report
Publication Date
Dec 01, 1991
Accession Number
ADA259650

Entities

People

  • Brian Kozminchuk

Organizations

  • Defence Research and Development Canada

Tags

Communities of Interest

  • C4I
  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Algorithms
  • Bandpass Filters
  • Communication Systems
  • Computer Simulations
  • Estimators
  • Filters
  • Filtration
  • Frequency
  • Gaussian Noise
  • Kalman Filtering
  • Kalman Filters
  • Low Pass Filters
  • National Security
  • Security
  • Simulations
  • Spread Spectrum
  • Steady State

Fields of Study

  • Engineering

Readers

  • Adaptive Control and Estimation with Uncertainty in Dynamic Systems.
  • Radio communications and signal processing.