Calibration and validation of high frequency radar for ocean surface current mapping

Approved for public release, distribution is unlimited === High Frequency (HF) radar backscatter instruments are being developed and tested in the marine science and defense science communities for their abilities to sense surface parameters remotely in the coastal ocean over large areas. In the Nav...

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Main Author: Kim, Kyung Cheol
Other Authors: Paduan, Jeffrey D.
Format: Others
Published: Monterey, California. Naval Postgraduate School June
Subjects:
Online Access:http://hdl.handle.net/10945/1564
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spelling ndltd-nps.edu-oai-calhoun.nps.edu-10945-15642017-05-24T16:07:12Z Calibration and validation of high frequency radar for ocean surface current mapping Kim, Kyung Cheol Paduan, Jeffrey D. Ramp, Steven R. Department of Oceanography Ocean currents Radar Calibration HF radar Ocean surface current Calibration MUSIC algorithm Approved for public release, distribution is unlimited High Frequency (HF) radar backscatter instruments are being developed and tested in the marine science and defense science communities for their abilities to sense surface parameters remotely in the coastal ocean over large areas. In the Navy context, the systems provide real-time mapping of ocean surface currents and waves critical for characterizing and forecasting the battle space environment. In this study, the performance of a network of four CODAR (Coastal Ocean Dynamics Application Radar) SeaSonde HF radars, using the Multiple Signal Classification (MUSIC) algorithm for direction finding, is described for the period between July to September 2003. Comparisons are made in Monterey Bay with moored velocity observations, with four radar baseline pairs, and with velocity observations from sixteen drifter deployments. All systems measure ocean surface current and all vector currents are translated into radial current components in the direction of the various radar sites. Measurement depths are 1 m for the HF radar-derived currents, 12 to 20 m for the ADCP bin nearest to the surface at the M1 mooring site, and 8 m for the drifter-derived velocity estimates. Comparisons of HF radar-M1 mooring buoy, HF radar-HF radar (baseline), and HF radar-drifter data yield improvements of - 1.7 to 16.7 cm/s rms differences and -0.03 to 0.35 correlation coefficients when measured antenna patterns are used. The mooring comparisons and the radar-to-radar baseline comparisons indicate angular shifts of 10Ê» to 30Ê» for radial currents produced using ideal antenna patterns and 0Ê» to 15Ê» angular shifts for radial currents produced using measured patterns. The comparisons with drifter-derived radial currents indicate that these angular biases are not constant across all look directions, even though the local antenna pattern distortions were taken into account through the use of measured antenna patterns. In particular, data from the SCRZ and MLNG radar sites show varied pointing errors across the range of angles covered. Lieutenant Commander, Republic of Korea Navy June 2004 2012-03-14T17:32:17Z 2012-03-14T17:32:17Z 2004-06 Thesis http://hdl.handle.net/10945/1564 Copyright is reserved by the copyright owner xvi, 74 p. : ill. (some col.), col. maps application/pdf Monterey, California. Naval Postgraduate School
collection NDLTD
format Others
sources NDLTD
topic Ocean currents
Radar
Calibration
HF radar
Ocean surface current
Calibration
MUSIC algorithm
spellingShingle Ocean currents
Radar
Calibration
HF radar
Ocean surface current
Calibration
MUSIC algorithm
Kim, Kyung Cheol
Calibration and validation of high frequency radar for ocean surface current mapping
description Approved for public release, distribution is unlimited === High Frequency (HF) radar backscatter instruments are being developed and tested in the marine science and defense science communities for their abilities to sense surface parameters remotely in the coastal ocean over large areas. In the Navy context, the systems provide real-time mapping of ocean surface currents and waves critical for characterizing and forecasting the battle space environment. In this study, the performance of a network of four CODAR (Coastal Ocean Dynamics Application Radar) SeaSonde HF radars, using the Multiple Signal Classification (MUSIC) algorithm for direction finding, is described for the period between July to September 2003. Comparisons are made in Monterey Bay with moored velocity observations, with four radar baseline pairs, and with velocity observations from sixteen drifter deployments. All systems measure ocean surface current and all vector currents are translated into radial current components in the direction of the various radar sites. Measurement depths are 1 m for the HF radar-derived currents, 12 to 20 m for the ADCP bin nearest to the surface at the M1 mooring site, and 8 m for the drifter-derived velocity estimates. Comparisons of HF radar-M1 mooring buoy, HF radar-HF radar (baseline), and HF radar-drifter data yield improvements of - 1.7 to 16.7 cm/s rms differences and -0.03 to 0.35 correlation coefficients when measured antenna patterns are used. The mooring comparisons and the radar-to-radar baseline comparisons indicate angular shifts of 10Ê» to 30Ê» for radial currents produced using ideal antenna patterns and 0Ê» to 15Ê» angular shifts for radial currents produced using measured patterns. The comparisons with drifter-derived radial currents indicate that these angular biases are not constant across all look directions, even though the local antenna pattern distortions were taken into account through the use of measured antenna patterns. In particular, data from the SCRZ and MLNG radar sites show varied pointing errors across the range of angles covered. === Lieutenant Commander, Republic of Korea Navy
author2 Paduan, Jeffrey D.
author_facet Paduan, Jeffrey D.
Kim, Kyung Cheol
author Kim, Kyung Cheol
author_sort Kim, Kyung Cheol
title Calibration and validation of high frequency radar for ocean surface current mapping
title_short Calibration and validation of high frequency radar for ocean surface current mapping
title_full Calibration and validation of high frequency radar for ocean surface current mapping
title_fullStr Calibration and validation of high frequency radar for ocean surface current mapping
title_full_unstemmed Calibration and validation of high frequency radar for ocean surface current mapping
title_sort calibration and validation of high frequency radar for ocean surface current mapping
publisher Monterey, California. Naval Postgraduate School
publishDate June
url http://hdl.handle.net/10945/1564
work_keys_str_mv AT kimkyungcheol calibrationandvalidationofhighfrequencyradarforoceansurfacecurrentmapping
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