Accounting for Ionospheric Variability and Irregularity in High Direction Finding

Abstract

High frequency (HF) radio wave propagation has long been the backbone of many short and long range communication networks. The reasons are straightforward: the technology is well established, the systems are relatively inexpensive and easily fieldable, and the reliability (while not perfect) is high enough to meet a large body of communication needs. In a similar vein, the interception of HF communications is one means of gaining additional intelligence in a military engagement. Taken an additional step, the interception of HF communications can also be used to locate the position of the transmitter, which knowledge may be of a strategic or tactical value. HF radio waves propagate in two modes: the ground wave, which can be detected out to distances on the order of 50 km, and the direct wave, which when reflected from the ionosphere, is known as the skywave and can be detected out to very long distances. The radio source location technique for a single station receiver consists of measuring the angle of arrival of the signal of interest in three dimensions. The problem then consists of tracing the signal's path back through the ionosphere to the source, the successful solution of which depends on a knowledge of the state of the ionosphere.

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Document Details

Document Type
Technical Report
Publication Date
Jan 01, 1981
Accession Number
ADA115049

Entities

People

  • Melvin G. Heaps

Organizations

  • United States Army Communications-Electronics Command

Tags

Communities of Interest

  • Advanced Electronics
  • Weapons Technologies

DTIC Thesaurus Topics

  • Accuracy
  • Angle Of Arrival
  • Atmospheric Sciences
  • Direction Finding
  • Electron Density
  • Electrons
  • Frequency
  • Gravity Waves
  • Ionosondes
  • Ionosphere
  • Ionospheric Disturbances
  • Position (Location)
  • Radio Frequency
  • Radio Waves
  • Transmitters
  • Wave Propagation
  • Waves

Readers

  • Space/Atmospheric Physics.
  • Systems Analysis and Design
  • Tactical Satellite Communications Systems Engineering.