Analysis of UHF-band sea clutter reflectivity at low grazing angles in offshore waters of the Yellow Sea

Abstract

ABSTRACT Reflectivity is an important characteristic of sea clutter that depends on the parameters of the radar and the environment. This paper presents reflectivity measurements of UHF-band horizontal polarized sea clutter based upon data collected in the offshore waters of the Yellow Sea of China at low grazing angles. During the experiment, the oceanic and meteorological conditions were recorded by the Datawell Waverider 4 and Lufft WS700-UMB on the sea surface. The factors that affect the reflectivity acquisition are analysed and the selective median filtering method in average Doppler power spectrum is presented to remove the effect of ground clutter from the sidelobes of the antenna beam pattern and the normalized reflectivity of the sea surface is computed. The applicability of the four classical reflectivity empirical models to the datasets is analysed. The results show that the Hybrid (HYB) and Technology Service Corporation (TSC) models are suitable while the Georgia Institute of Technology (GIT) and Naval Research Laboratory (NRL) models are unsuitable for the UHF-band horizontal polarized sea clutter in the offshore waters of the Yellow Sea of China.