A SURVEY OF LOW REFLECTION COEFFICIENTS FOR VARIOUS TYPES OF LAND AND FROZEN SEA FOR NORMAL INCIDENCE AT 1600 MC/S

Abstract

During development on radio terrain clearance indicators, work was done to measure the reflection coefficients from terrains expected to have the lowest values. The measurements were made at 1600 mc. They depended upon the reception in an aircraft flying over the terrain, of a signal transmitted vertically downwards from the aircraft and reflected back to it. The reflection coefficient of desert sand, 0.15 for an assumption of 0.85 for sea, was in agreement with a previously reported value at 400 mc and was considered to be the lowest reflection coefficient to be found from any natural terrain. Measurements over barren, frozen, arctic terrain or sea covered by several feet of ice produced reflection coefficients equal to those from desert sand. However, over terrain deeply frozen and covered by deep snow and vegetation, appreciably smaller reflection coefficients were measured.

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Document Details

Document Type
Technical Report
Publication Date
Jan 01, 1953
Accession Number
AD0007039

Entities

People

  • J. K. Garlick

Tags

Communities of Interest

  • Air Platforms
  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Aircrafts
  • Attenuation
  • Bays
  • Clearances
  • Coefficients
  • Gain
  • Government (Foreign)
  • Hudson Bay
  • Ice
  • Indicators
  • Measurement
  • Military Equipment
  • Moisture
  • Moisture Content
  • Open Water
  • Snow Cover
  • Water

Readers

  • Electromagnetic Wave Scattering and Antenna Radiation Engineering
  • Geotechnical Engineering.