UHF ACTIVE CANCELLATION FILTER

Abstract

A UHF cancellation filter is described for use over the frequency range 200-400 Mc. The filter can reject CW interference by phase locking an oscillator to the interfering signal and adding the phase-locked signal in such a manner as to produce cancellation of the interference. A superheterodyne system is employed so that interfering signals as low as -80 dbm may be cancelled throughout the 200-400 Mc frequency range. By careful adjustment of the phase and amplitude of the cancellation signal, the interfering signal can be reduced as much as 60 db. The cancellation filter is designed for use in a 50 ohms system and is inserted between the antenna and receiver. When the cancellation filter is inoperative, the receiving system may be used in a normal manner with the filter remaining in the receiving system.

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Document Details

Document Type
Technical Report
Publication Date
May 01, 1966
Accession Number
AD0486927

Entities

People

  • J. A. Hart Jr.

Organizations

  • Georgia Tech

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Amplifiers
  • Amplitude
  • Attenuation
  • Detectors
  • Diagrams
  • Filters
  • Frequency
  • Local Oscillators
  • Losses
  • Low Pass Filters
  • Oscillators
  • Phase Detectors
  • Phase Shift
  • Resonant Circuits
  • Schematic Diagrams
  • Signal Generators
  • Tuned Circuits

Fields of Study

  • Engineering

Readers

  • Electronics Engineering
  • Radio communications and signal processing.