HF Radar Wave Measurements in the Presence of Ship Echoes
- Problems and Solutions
Presented at the Oceans 2005 Euproe Conference
Brest, France, 20-23 June 2005
Klaus-Werner Gurgel and
University of Hamburg, Institute of Oceanography,
Bundesstrasse 53, D-20146 Hamburg, Germany.
Tel: +49-40-42838-5742, Fax: +49-40-42838-5713,
A full paper has been published in the conference
HF radar is an important tool to remotely measure oceanographic parameters
like currents and waves from shore over large areas up to 6,500 km2.
Maps of these parameters can be obtained 3 times per hour.
In areas of high ship traffic, there are ship echoes within the radar
backscatter signal, which can appear in the frequency bands of the Doppler
spectrum which are used to extract current- and wave information.
While the current speed is derived from the first-order Bragg peaks, wave
height and direction is calculated from the second-order bands around the
first-order peaks. The second-order bands require 15 to 20 times the bandwidth
of the first-order peaks and their amplitude is about 20 dB lower. Due to
these facts, ship echoes can cause problems especially to wave algorithms.
This paper discusses the special signatures of ship echoes and shows
possibilities to identify and to track ships.
last update 05-APR-2005