Rotor Effects on L-Band Signals Received by Helicopter Antennas. A Theoretical Study. Part I: Amplitude Reduction and Phase Shift. (Schielding Effect).

Abstract

Rotor effects on L-band navigation signals received by helicopter antennas are examined theoretically. Two types of distortions are distinguished: (a) the amplitude reduction and phase shift of CW-signals due to periodic shadowing of the antenna by the rotor (shielding effect) and (b) the distortion of phase reversals assumed to occur at predetermined intervals in the incident signals. Numerical evaluations have been performed using the pertinent dimensions of a UH-1 helicopter. It was found that the shielding effect may reduce the received power by 10 dB while the phase shift does not exceed 90 degrees. (Modified author abstract)

Document Details

Document Type
Technical Report
Publication Date
Sep 01, 1974
Accession Number
AD0787363

Entities

People

  • C. M. Desantis
  • F. Schwering

Organizations

  • United States Army Communications-Electronics Command

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Abstracts
  • Amplitude
  • Distortion
  • Helicopters
  • Intervals
  • L Band
  • Navigation
  • Phase Shift
  • Shielding
  • Test And Evaluation

Fields of Study

  • Engineering

Readers

  • Aerospace Engineering
  • Plasma Physics / Magnetohydrodynamics
  • Radar Systems Engineering.