Application of Wavelet Transform Techniques to Spread Spectrum Demodulation and Jamming

Abstract

This project has investigated the application of wavelet methods in spread spectrum communications. Use of the wavelet transform as an alternative to the short-time Fourier and quadratic time-frequency transforms for measuring critical parameters of intercepted slow frequency hopping communication signals has been explored. Direct application of the wavelet transform was found to not offer performance advantages over the Fourier transform in this application. However, use of the wavelet transform in conjunction with Fourier methods provided an efficient hybrid framework for precise measurement of hopping times and frequencies. A new approach to multiple-access spread spectrum communications was also developed in this project. This approach employs orthogonal wavelets as symbols for encoding digital communication signals. Several users can transmit simultaneously in the same medium using channels defined by wavelet scale in much the same way that channels are defined by frequency in traditional frequency division multiple access. Appropriate choices of wavelet symbols make the transmitted signals robust with respect to detection and jamming.... Wavelets, Spread spectrum communication systems

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Document Details

Document Type
Technical Report
Publication Date
Feb 26, 1993
Accession Number
ADA267389

Entities

People

  • Douglas Cochran

Organizations

  • Arizona State University

Tags

Communities of Interest

  • C4I
  • Energy and Power Technologies
  • Human Systems
  • Materials and Manufacturing Processes

DTIC Thesaurus Topics

  • Code Division Multiple Access
  • Coding
  • Communication Systems
  • Digital Communications
  • Digital Data
  • Electrical Engineering
  • Frequency
  • Frequency Agility
  • Frequency Bands
  • Frequency Division Multiple Access
  • Frequency Domain
  • Information Theory
  • Measurement
  • Multiple Access
  • Signal Processing
  • Spread Spectrum
  • Time Division Multiple Access

Fields of Study

  • Engineering

Readers

  • Approximation Theory.
  • Radio communications and signal processing.
  • Systems Analysis and Design