THEORY OF GROUND-WAVE PROPAGATION ACROSS A ROUGH SEA AT DEKAMETER WAVELENGTHS

The effect of sea state on ground-wave propagation across the ocean is computed in the HF and VHF region. The history and present understanding of ground-wave propagation is briefly reviewed, especially as concerns the influence of roughness. The approach of the analysis is to derive an effective surface impedance at grazing which includes the effects of roughness. To do this, the statistical boundary perturbation approach of Rice is applied to the sea surface, which is slightly rough at HF/VHF. In addition, the Leontovich (or impedance) boundary condition is employed because ocean water is a good (but not perfect) conductor at these frequencies. The analysis shows that the total effective impedance at the surface can be expressed as two terms: (1) the impedance of a perfectly smooth seawater surface at grazing, and (2) a second term accounting for roughness. (Author)

• Corporate Authors:

  Battelle Memorial Institute

  505 King Avenue
  Columbus, OH  United States  43201
• Authors:
  • Barrick, Donald E
• Publication Date: 1970-1

Media Info

• Pagination: 140 p.

Subject/Index Terms

• TRT Terms: Electromagnetic wave propagation; Radio signals; Radio wave propagation; Very high frequency; Wave motion
• Old TRIS Terms: Ground waves; Vhf communications
• Subject Areas: Marine Transportation; Operations and Traffic Management;

Filing Info

• Accession Number: 00015376
• Record Type: Publication
• Source Agency: National Technical Information Service
• Files: TRIS
• Created Date: May 13 1971 12:00AM