Walsh Adaptive Filter

Abstract

This report describes a technique and equipment for detecting pulsed signals in a high noise environment. The performance of this technique approaches matched filter techniques for signals where the pulse parameters are not known a-priori. A common problem in the area of signal processing is that of the detection of pulse signals having very low signal-to-noise ratios (SNR). The problem is worsened when major signal parameters (pulse width and time of arrival) are not known. The purpose of this program was to develop an exploratory development model of a system to detect the presence of low SNR signals, on a single pulse-by-pulse basis. The technique chosen for this program was the use of the Walsh Transform as the basis for a two transform digital filter. This technique had previously been demonstrated both in software and in breadboard hardware form by AEL as a result on in-house IR and D programs. This program was to further develop the technique and to fabricate a unit suitable for test and evaluation purposes against a variety of potential applications. The system name, Walsh Adaptive Filter (WAF), was derived from the use of a Walsh transform to adaptively filter signals of varying pulse widths and repetition rates. An exploratory development model was fabricated, tested and delivered to RADC.

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Document Details

Document Type
Technical Report
Publication Date
Apr 01, 1978
Accession Number
ADA055170

Entities

People

  • John F. Hurst

Tags

Communities of Interest

  • Energy and Power Technologies
  • Materials and Manufacturing Processes
  • Space

DTIC Thesaurus Topics

  • Adaptive Filters
  • Air Force
  • Central Processing Units
  • Computer Programs
  • Computers
  • Converters
  • Delay Circuits
  • Detection
  • Detectors
  • False Alarms
  • Filtration
  • Frequency
  • Measurement
  • Power Supplies
  • Processing Equipment
  • Signal Processing
  • Test And Evaluation

Fields of Study

  • Engineering

Readers

  • Acoustical Oceanography.
  • Approximation Theory.
  • Electrical Engineering