access icon openaccess Study of wind direction factor based on sea clutter in littoral environments

This is an open access article published by the IET under the Creative Commons Attribution -NonCommercial License (http://creativecommons.org/licenses/by-nc/3.0/)
Received 21/02/2019, Accepted 07/05/2019, Published 11/07/2019

Wind direction factor, as a part of some empirical sea clutter models of the normalised radar cross-section (NRCS), is closely related to wind direction angle, grazing angle and radar wavelength. The use of the low-grazing-angle (LGA) sea clutter measured by UHF-band radar on the Lingshan island to discuss the characteristic of the wind direction factor is investigated. The results indicate that the upwind-to-crosswind ratio of NRCS, which is calculated by the empirical model, could not provide a good fit for grazing angles <10°. It was found that the ratio obtained from measured data varies with the sea state (SS) at the same grazing angle, conversely the empirical models was constant. Based on deep analysis of the results, we finally find out the influence of SS could not be ignored. In addition, some suggestions to improve sea clutter model of littoral environments were proposed for practical applications.

Inspec keywords: wind; marine radar; radar clutter; radar cross-sections; atmospheric techniques; remote sensing by radar

Other keywords: empirical model; wind direction factor; radar wavelength; UHF-band radar; sea clutter model; wind direction angle; littoral environments; low-grazing-angle sea clutter; normalised radar cross-section; grazing angle; sea state

Subjects: Instrumentation and techniques for geophysical, hydrospheric and lower atmosphere research; Radar theory; Radar equipment, systems and applications; Atmospheric, ionospheric and magnetospheric techniques and equipment; Winds and their effects in the lower atmosphere

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