Premium
Ground Backscatter Observed With High Resolution Oblique Sounders
Author(s) -
Basler Roy P.,
Scott Thomas D.
Publication year - 1972
Publication title -
radio science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.371
H-Index - 84
eISSN - 1944-799X
pISSN - 0048-6604
DOI - 10.1029/rs007i002p00239
Subject(s) - backscatter (email) , azimuth , geology , depth sounding , beamwidth , optics , physics , antenna (radio) , geodesy , remote sensing , telecommunications , computer science , wireless , oceanography
The amplitude of ground backscatter at high frequency (HF) recorded with oblique sounding equipment that utilizes azimuthal antenna beamwidths of about 6° and effective pulse lengths of about 50 μsec is characterized by sharp spikes that rise 10 to 20 db above the diffuse background clutter and have a range extent as short as the pulse length. These spikes suggest that the backscattering efficiency of the ground is highly nonuniform as a result of the occasional presence of a localized surface feature with a backscatter cross section one or two orders of magnitude larger than any object in the surrounding countryside. When short‐pulse ground backscatter echoes are displayed as intensity modulated range versus azimuth records, these sharp spikes produce discrete echoes with an azimuthal extent approximately equal to the effective beamwidth of the antenna. The sources of many of these discrete echoes have been identified with specific topographic and geographic features, including cities and mountains in the western United States and islands in the Caribbean Sea.