VLF Nighttime Data Analysis
This paper documents a VLF/LF Data Analysis task by the Naval Ocean Systems Center to improve the modeling of the nighttime ionosphere when making propagation predictions with the LWPC computer program. The task utilizes an extensive database of VLF measured data recorded during the 1985-1986 trips...
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1991
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ftdtic:ADA234006 2023-05-15T17:30:50+02:00 VLF Nighttime Data Analysis TELECOMMUNICATION SCIENCE ASSOCIATES INC SAN DIEGO CA 1991-09 text/html http://www.dtic.mil/docs/citations/ADA234006 http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA234006 en eng http://www.dtic.mil/docs/citations/ADA234006 APPROVED FOR PUBLIC RELEASE DTIC AND NTIS Plasma Physics and Magnetohydrodynamics Radiofrequency Wave Propagation *DATA PROCESSING *NIGHT *OCEAN ENVIRONMENTS COMPUTER PROGRAMS DATA BASES FREQUENCY IONOSPHERE PROPAGATION POSITION(LOCATION) SHIPS PREDICTIONS NAVY TIME OCEANS RANGE(DISTANCE) MERCHANT VESSELS NORTH ATLANTIC OCEAN PLOTTING VERY LOW FREQUENCY *IONOSPHERIC PROPAGATION *ELECTRON DENSITY LOW FREQUENCY COLLISION FREQUENCY DATA ANALYSIS NIGHTTIME Text 1991 ftdtic 2016-02-21T07:58:32Z This paper documents a VLF/LF Data Analysis task by the Naval Ocean Systems Center to improve the modeling of the nighttime ionosphere when making propagation predictions with the LWPC computer program. The task utilizes an extensive database of VLF measured data recorded during the 1985-1986 trips of the merchant ship GTS Callaghan in the North Atlantic area. By constraining the Callaghan data to those periods when both the ship and the distant transmitters were in time zones consistent with all-nighttime propagation, and by eliminating data from trips outside the principal area of interest, an aggregated set of recorded data was assembled for each frequency of concern. Four frequencies were examined: 16.0, 19.0, 21.4 and 24.0 kHz. Recorded data sets were graphed as signal vs. distance plots, computing distance from the transmitter for each ship's location. The LWPC program was then utilized to compute signal vs. distance along a typical path in the same ocean area, and the predicted and recorded data were compared. By changing the LWPC parameters different propagation predictions were compared with the recorded data until a best fit was obtained. Text North Atlantic Defense Technical Information Center: DTIC Technical Reports database |
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Open Polar |
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Defense Technical Information Center: DTIC Technical Reports database |
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language |
English |
topic |
Plasma Physics and Magnetohydrodynamics Radiofrequency Wave Propagation *DATA PROCESSING *NIGHT *OCEAN ENVIRONMENTS COMPUTER PROGRAMS DATA BASES FREQUENCY IONOSPHERE PROPAGATION POSITION(LOCATION) SHIPS PREDICTIONS NAVY TIME OCEANS RANGE(DISTANCE) MERCHANT VESSELS NORTH ATLANTIC OCEAN PLOTTING VERY LOW FREQUENCY *IONOSPHERIC PROPAGATION *ELECTRON DENSITY LOW FREQUENCY COLLISION FREQUENCY DATA ANALYSIS NIGHTTIME |
spellingShingle |
Plasma Physics and Magnetohydrodynamics Radiofrequency Wave Propagation *DATA PROCESSING *NIGHT *OCEAN ENVIRONMENTS COMPUTER PROGRAMS DATA BASES FREQUENCY IONOSPHERE PROPAGATION POSITION(LOCATION) SHIPS PREDICTIONS NAVY TIME OCEANS RANGE(DISTANCE) MERCHANT VESSELS NORTH ATLANTIC OCEAN PLOTTING VERY LOW FREQUENCY *IONOSPHERIC PROPAGATION *ELECTRON DENSITY LOW FREQUENCY COLLISION FREQUENCY DATA ANALYSIS NIGHTTIME VLF Nighttime Data Analysis |
topic_facet |
Plasma Physics and Magnetohydrodynamics Radiofrequency Wave Propagation *DATA PROCESSING *NIGHT *OCEAN ENVIRONMENTS COMPUTER PROGRAMS DATA BASES FREQUENCY IONOSPHERE PROPAGATION POSITION(LOCATION) SHIPS PREDICTIONS NAVY TIME OCEANS RANGE(DISTANCE) MERCHANT VESSELS NORTH ATLANTIC OCEAN PLOTTING VERY LOW FREQUENCY *IONOSPHERIC PROPAGATION *ELECTRON DENSITY LOW FREQUENCY COLLISION FREQUENCY DATA ANALYSIS NIGHTTIME |
description |
This paper documents a VLF/LF Data Analysis task by the Naval Ocean Systems Center to improve the modeling of the nighttime ionosphere when making propagation predictions with the LWPC computer program. The task utilizes an extensive database of VLF measured data recorded during the 1985-1986 trips of the merchant ship GTS Callaghan in the North Atlantic area. By constraining the Callaghan data to those periods when both the ship and the distant transmitters were in time zones consistent with all-nighttime propagation, and by eliminating data from trips outside the principal area of interest, an aggregated set of recorded data was assembled for each frequency of concern. Four frequencies were examined: 16.0, 19.0, 21.4 and 24.0 kHz. Recorded data sets were graphed as signal vs. distance plots, computing distance from the transmitter for each ship's location. The LWPC program was then utilized to compute signal vs. distance along a typical path in the same ocean area, and the predicted and recorded data were compared. By changing the LWPC parameters different propagation predictions were compared with the recorded data until a best fit was obtained. |
author2 |
TELECOMMUNICATION SCIENCE ASSOCIATES INC SAN DIEGO CA |
format |
Text |
title |
VLF Nighttime Data Analysis |
title_short |
VLF Nighttime Data Analysis |
title_full |
VLF Nighttime Data Analysis |
title_fullStr |
VLF Nighttime Data Analysis |
title_full_unstemmed |
VLF Nighttime Data Analysis |
title_sort |
vlf nighttime data analysis |
publishDate |
1991 |
url |
http://www.dtic.mil/docs/citations/ADA234006 http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA234006 |
genre |
North Atlantic |
genre_facet |
North Atlantic |
op_source |
DTIC AND NTIS |
op_relation |
http://www.dtic.mil/docs/citations/ADA234006 |
op_rights |
APPROVED FOR PUBLIC RELEASE |
_version_ |
1766127945926049792 |