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global telephone, FAX, and television link. Today several state-sponsored and commercial satellite communication systems provide data links (including positioning
data) from surface Data Collecting Platforms (DCP) throughout the world oceans.
DCP data can in most cases be received by the operator through internet links.
The ARGOS Data Collection and location System (DCS) is the precursor to all
satellite data relay and platform location services. Operational since 1978, ARGOS
instruments aboard US, European, and weather satellites in polar orbit provide both
a data transmission service and platform location based on the Doppler Effect with
precision ranging from about 150 m to 1000 m. It is an older, less precise, but
effective alternative and supplement for platform location to the newer, highly precise GPS system (see below). However, ARGOS provides data relay for platforms
equipped with GPS receivers allowing GPS precision as needed. Initially emplaced
and operated jointly by the US National Atmospheric and Space administration
(NASA), the US National Oceanic and Atmospheric Agency (NOAA), and the
French Centre National d’Etudes Spatiales (CNES) and joined today by the
European Organization of the Exploitation of Meteorological Satellites
(EUMETSAT) and the Indian Space Research Organization (ISRO), ARGOS instruments operate aboard NOAA and EUMETSAT polar orbiting weather satellites in
sun synchronous low Earth orbits at altitudes below 900 km. ARGOS-3 transmitters
(currently in their third generation) aboard surface platforms operate at a frequency
of 401.65 MHz in the lower UHF radio band. Radiated power is about 5 W, in bursts
of less than 1 s at intervals of 45–200 s allowing the use of low power sources such
as batteries and solar panels (IOC/WMO DATA BUOY CO-OPERATION PANEL,
2011).
NOAA operates a Geostationary Operational Environmental Satellite (GOES)
constellation of satellites in equatorial geostationary orbit at an altitude of 35,786 km.
Two primary operational satellites cover the Atlantic Ocean to the east and the
Pacific to the west of the USA. GOES East orbits directly above South America and
GOES West orbits above the eastern Pacific Ocean. GOES satellites’ primary mission is to support weather forecasting, to track severe storms, and to assist in meteorological research. However, essential to their meteorological mission is the
provision of a communication link for surface-based environmental observation
platforms. The GOES Data Collection System (DCS) offers robust data relay for
ocean observations from diverse autonomous platforms located in the Eastern and
Central Pacific Ocean and throughout most of the Atlantic Ocean. Since the number
of DCPs is dictated by the number of available channels, assigning narrow temporal
communication windows to individual DCPs allows increasing the number of platform communications. Platforms usually collect data at higher programmed rates
but transmit data packets at lower rates, typically hourly for operational ocean
observing surface buoys. The DCS aboard GOES receives data from more than
10,000 DCPs. DCP data is received at GOES East through channels at 468.250 MHz
(domestic) and 402.200 MHZ (international). DCP data is then relayed to ground
stations via the microwave radar L band at 1694.500 GHz. DCP interrogation is also
available at 2034.9000 MHz (Nestlebush 1994). Similarly, in support of its meteorological mission, the METEOSAT system operated by EUMETSAT supports DCP
5 Signal Conditioning, Data Telemetry, Command Signaling and Platform Positioning…
global telephone, FAX, and television link. Today several state-sponsored and commercial satellite communication systems provide data links (including positioning
data) from surface Data Collecting Platforms (DCP) throughout the world oceans.
DCP data can in most cases be received by the operator through internet links.
The ARGOS Data Collection and location System (DCS) is the precursor to all
satellite data relay and platform location services. Operational since 1978, ARGOS
instruments aboard US, European, and weather satellites in polar orbit provide both
a data transmission service and platform location based on the Doppler Effect with
precision ranging from about 150 m to 1000 m. It is an older, less precise, but
effective alternative and supplement for platform location to the newer, highly precise GPS system (see below). However, ARGOS provides data relay for platforms
equipped with GPS receivers allowing GPS precision as needed. Initially emplaced
and operated jointly by the US National Atmospheric and Space administration
(NASA), the US National Oceanic and Atmospheric Agency (NOAA), and the
French Centre National d’Etudes Spatiales (CNES) and joined today by the
European Organization of the Exploitation of Meteorological Satellites
(EUMETSAT) and the Indian Space Research Organization (ISRO), ARGOS instruments operate aboard NOAA and EUMETSAT polar orbiting weather satellites in
sun synchronous low Earth orbits at altitudes below 900 km. ARGOS-3 transmitters
(currently in their third generation) aboard surface platforms operate at a frequency
of 401.65 MHz in the lower UHF radio band. Radiated power is about 5 W, in bursts
of less than 1 s at intervals of 45–200 s allowing the use of low power sources such
as batteries and solar panels (IOC/WMO DATA BUOY CO-OPERATION PANEL,
2011).
NOAA operates a Geostationary Operational Environmental Satellite (GOES)
constellation of satellites in equatorial geostationary orbit at an altitude of 35,786 km.
Two primary operational satellites cover the Atlantic Ocean to the east and the
Pacific to the west of the USA. GOES East orbits directly above South America and
GOES West orbits above the eastern Pacific Ocean. GOES satellites’ primary mission is to support weather forecasting, to track severe storms, and to assist in meteorological research. However, essential to their meteorological mission is the
provision of a communication link for surface-based environmental observation
platforms. The GOES Data Collection System (DCS) offers robust data relay for
ocean observations from diverse autonomous platforms located in the Eastern and
Central Pacific Ocean and throughout most of the Atlantic Ocean. Since the number
of DCPs is dictated by the number of available channels, assigning narrow temporal
communication windows to individual DCPs allows increasing the number of platform communications. Platforms usually collect data at higher programmed rates
but transmit data packets at lower rates, typically hourly for operational ocean
observing surface buoys. The DCS aboard GOES receives data from more than
10,000 DCPs. DCP data is received at GOES East through channels at 468.250 MHz
(domestic) and 402.200 MHZ (international). DCP data is then relayed to ground
stations via the microwave radar L band at 1694.500 GHz. DCP interrogation is also
available at 2034.9000 MHz (Nestlebush 1994). Similarly, in support of its meteorological mission, the METEOSAT system operated by EUMETSAT supports DCP
5 Signal Conditioning, Data Telemetry, Command Signaling and Platform Positioning…