Geosciences Research Division
GODC
GRD/NOAA Operational Data Center
- ORGANIZATION
- FUNCTIONS
- Real-Time Operation Monitoring
- Data Communication and Preprocessing
- The Information Distribution
ORGANIZATION
The GRD/NOAA Operational Data Center (GODC) was established by the
National Ocean Service (NOS) of the National Oceanic and Atmospheric
Administration (NOAA) for installation and monitoring permanent GPS
tracking stations. GODC currently monitors the following stations:
- Global Tracking
- Atlantic Oceanographic & Met Lab [AOML]
- Barbados [BARB]
- Bermuda [BRMU]
- Fortaleza, Brazil [FORT]
- Kellyville, Greenland [KELY]
- Richmond, Florida [RCM6]
- Westford, Massachusetts WES2]
- CORS Tracking
- Table Mountain, Colorado [TMGO]
- Chesapeake Bay Tracking
- Annapolis, Maryland [USNA]
- Duck, North Carolina [DUCK]
- Gloucester Point, Virginia [GLPT]
- Horn Point, Maryland [HNPT]
- Solomons Island, Maryland [SOL1]
- Wachapreaque, Virginia [VIMS]
The GPS data from these sites is available by
anonymous ftp.
The data collected from the Global Tracking network is sent to the
International GPS Service for Geodynamics
(IGS) daily. These stations
were established in support of an international cooperative effort for
computing daily precise GPS orbits for geodynamic research.
The CORS station is a part of the
Continuous Operating Reference System
(CORS)
Data Center of the National Geodetic Survey.
And the Chesapeake Bay stations are part of a partnership project with
NASA for environmental studies.
FUNCTIONS
Real-Time Operation Monitoring
A GRD/NOAA GPS tracking system consists of a dual frequency GPS receiver,
a GPS antenna, a PC with sufficient disk space, an uninterrupted power
supply, a high speed modem, a network connection, and communication
software packages. Some stations are equipped with hydrogen maser
frequency standards and high precision barometers.
The tracking system provides a remote operation monitoring capability
from GODC using PCs and modems. The common monitoring features used are:
- Examining receiver tracking status
- Modifying data download procedure
- Changing tracking configuration
- Performing troubleshooting
- Rebooting the on-site PC or receiver
Data Communication and Preprocessing
Barometer measurements are continuously recorded onto the PC's hard disk
every 10 minutes. The real-time GPS data collected and stored inside the
GPS receiver are downloaded onto the PC hard disk after UTC mid-night
via a direct connected RS232 cable. These data are, then, transferred
into the GODC HP755 computer via Internet.
After all data transfers are completed the HP755 starts the following tasks:
- Decompression
- Format conversion - binary to RINEX
- Quality Control
- UNIX compression
- Distribution
To access the data via Internet:
Network address:
gracie.grdl.noaa.gov [140.90.160.199]
FTP Login : anonymous
Directories :
dist/cignet/dxxxa_yy : GPS & meteorological data in RINEX format
dist/cignet/dxxxb_yy : GPS data in raw format
dist/cignet/Ngsorbits: NGS precise ephemeris
dist/cignet/Globals : Broadcast ephemeris
dist/cignet/site_logs: Station information
GODC normally keeps 200 days data on-line.
For off-line data,
users would need to send e-mail or contact GODC staff:
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