ARGOS SYSTEM

Why choose Argos? Worldwide tracking and environmental monitoring by

30 YEARS OF EXPERIENCE

22000 ACTIVE TRANSMITTERS PER MONTH

8000 ANIMALS TAGGED AND TRACKED

Argos is a unique worldwide location and data collection system dedicated to studying and protecting the environment.

Argos is a unique worldwide location and data collection system dedicated to studying and protecting the environment. Argos helps the scientific community to better monitor and understand our

environment, but also helps industry to comply with environmental protection regulations implemented by various governments.

To meet system use requirements, all programs using Argos have to be related in some way or form to environmental protection, awareness or study, or to protecting human life. Applications for which a clear governmental interest prevail are also approved.

Pioneer satellite system

Argos is a satellite-based system operating since 1978. The Argos system collects data from Pl a t f or m Terminal Transmitters, PTTs, and delivers this telemetry data to the users desktop. It was established under an agreement between:  French Space Agency (CNES)  National Oceanic and Atmospheric Administration (NOAA, USA) National Aeronautics and Space Administration (NASA , USA) Argos is operated and managed by Collecte, Localisation, (CLS), a CNES subsidiary near Toulouse, France and CLS America, a CLS subsidiary based in Washington, USA. The Argos instruments are housing on board of satellites of different organizations the NOAA, the Japanese space agency (NASDA) and the European Meteorological Satellite organization (Eumetel).

Two satellites are operational at any time.

The message of the PTTs are received on board of the satellites and relayed in real time to the ground. Additional the messages are stored and transmitted every time they pass over one of the 3 ground stations, located at Wallops Island (USA), Fairbanks (USA) and Lannion (France). The data are sending directly onto the Global Telecommunication System (GTS). Argos services offers the possibility your transmitters in the field, you'll be able to send messages to the PTT in the field.

Messages sent by PTT’s can be processed for location or data collection or both.

A robust system

The Argos system is:  6 satellites, which follow polar orbits at an altitude of about 850km (530 miles),  60 terrestrial receiving stations  2 data processing centers.

Unlike the Global Positioning System (GPS) that needs a minimum of three satellites to be in range to pinpoint an object's location, Argos is still so attractive and working so well after 30 years, the Argos system was designed as a very simple and robust system.

As a satellite passes overhead, it picks up data from a transmitter, which is continuously sending out messages in short pulses. During the 10 minutes or so that the satellite is in range, it will measure the frequency of each message it receives. However, an effect known as the Doppler shift means that each frequency the satellite receives is slightly different - as it moves towards a transmitter, it records a higher frequency, as it moves past it, it records a lower frequency. Using these frequency changes, together with the satellite's speed, position and the original frequency that the transmitter beamed out, the transmitter's position can be calculated.

Argos users are able to pick up the results via email, websites or via a "Google ".

System advantages

CLS operates Argos system and are constantly in contact with Argos users and try always to make sure the Argos system fits with their needs. Argos is constantly evolving:  Polar orbits  Worldwide coverage, by increasing the number of satellites  More data, by increasing the amount of data sent on each satellite pass  Optimization of transmitter power consumption  Reduction in the size of transmitters ( 4,5g smaller)

The three main capabilities in which Argos is evolving are:

Doppler location capability

The Argos processing centers use the Doppler effect to locate transmitters. The advantages of Doppler location are low transmitter power consumption and instant location opportunities throughout satellite passes (useful for marine animals for example).

GPS positioning

The Argos processing system uses the GPS receiver as a sensor and sends users their GPS positions as if they were sensor data. The processing system has been modified to make the GPS positions available in the same format as regular Doppler-derived locations. User can choose whichever form of location best suits their needs.

High sensitivity of satellite receiver t o transmitter messages

That means transmitters can be miniaturized and be operated on low radiated power, achieving good results with just 250 mW and using very low power, so that animals can be tracked over long distances.

GPS positions via Argos

Why GPS and ARGOS are different? There are two separate ways of location or tracking your transmitter:

Argos location: the Argos centers calculate your transmitter locations by measuring the Doppler shift on its transmit frequency. Even if you do not send sensor or other data, the minimum message length is 32 bits.

GPS positioning: if a GPS receiver is interfaced or built into your Argos transmitter, a dedicated processing module at the Argos centers can extract the GPS positions from your Argos messages, validate them, and output them as regular Argos positions. The coordinates in both cases are in latitude and longitude, in thousandths of degrees. The reference system is the World Geodetic System (WGS 84).

With Argos, keep your data accurate and up to date

The adv ant ages of sending GPS positions v i a t he Argos system:  having two location system s is more reliable than just one  GPS positions can be generated as often as you want  Accuracy is higher (within 100 meters) and does not depend on the transmitter quality  Positions can be spread evenly through the day  Providing the GPS positions in the Argos messages are in the format defined by CLS, they are output in latitude and longitude, and made available just like Argos locations.

How Argos works?

Powered by batteries or solar energy, the Argos transmitters send messages at regular intervals of short duration (less than one second) at Argos instruments on satellites that pass at 850 km altitude. The collected information is sent to sixty ground receiving stations that calculate the position of the beacons or buoys and retransmit all the two treatment centers in France (Toulouse) and United States (Washington). CLS centers data analyze and retransmit qualified data to Argos users (scientists, governments, industry, etc.)

Argos is a unique worldwide location and data collection system dedicated to studying and protecting the environment.

Argos transmitter A platform refers to any equipment integrating an Argos-certified transmitter.

Each platform is characterized by an identification number specific to its transmission electronics. A platform transmits periodic messages characterized by the following parameters:

Transmission Frequency (401.650 M Hz ± 30 k Hz), which must be stable as the location is computed on the basis of Doppler effect measurement. Repetition period, which is the interval of time between two consecutive message dispatches, varying between 90 and 200 seconds according to the use of the platform, platform identification number, all collected data.

The transmission duration of each message is less than one second.

Platforms: - Argos transmitters and packaging dedicated to wildlife tracking - Drifting buoys - Ice buoys - Subsurface Floats - Moored buoys

Argos satellites

Polar orbiting satellites collecting data: flying at an orbit of 850 km above the earth pick up the signals and store them on-board and relay them in real-time back to earth.

The Argos instrument flies aboard POES (Polar Orbiting Environmental Satellites) satellites of the National Oceanic and Atmospheric Administration (NOAA) and MetOp, of the European Organization for the Exploitation of Meteorological Satellites (Eumetsat). The first MetOp satellite was launched on 19 October 2006.

Argos messages are received by the satellite simultaneously. They are stored on the onboard recorder and retransmitted to the ground each time the satellite passes over one of the three main receiving stations based on Wallops Island (Virginia, United States), Fairbanks (Alaska, United States), and Svalbard (Norway), or they are retransmitted to the ground to regional reception stations in the satellites' field of view.

The satellites are on a polar orbit at an altitude of 850 km

The satellites see the North and South Poles on each orbital revolution. The orbit planes revolve around the polar axis at the same speed as the Earth around the Sun, i.e. one revolution a year. Each orbital revolution transects the equatorial plane at fixed local solar times. Therefore, each satellite passes within visibility of any given transmitter at almost the same local time each day. The time taken to complete a revolution around the Earth is approximately 100 minutes.

At any given time, each satellite simultaneously "sees" all transmitters within an approximate 5000 kilometer diameter "foot print", or visibility circle. As the satellite proceeds in orbit, the visibility circle sweeps a 5000 kilometer swath around the Earth, covering both poles.

Due to the Earth's rotation, the swath shifts 25° west (2800 km at the Equator) around the polar axis at each revolution. This results in overlap between successive swaths. Since overlap increases with latitude, the number of daily passes over a transmitter also increases with latitude.

At the poles, the satellites see each transmitter on every pass, approximately 14 times per day per satellite.

The period during which the satellite can receive messages from a platform is equivalent to the time during which the platform is within its visibility. On average this is 10 minutes.

Receiving stations

Nearly 60 stations receive real time data from the satellites and retransmit them to processing centers. This network distributed to provide w or l d wide coverage.

The three main receiving stations, Wallops Island and Fairbanks in the United States and Svalbard in Norway, collect all the messages recorded by the satellites during an orbit, thus providing worldwide cover.

Data received by the satellites are retransmitted to regional stations in real time if the station is within satellite visibility. The main receiving stations also receive data in real time.

Processing centers

There are t w o global Argos processing centers, one located just outside of Toulouse in Southwestern France, and the other near Washington, DC, USA. Once the data arrive at a processing center, locations are automatically calculated and information made available to users.

In the two processing centers with redundant operation, the computers calculate locations and process the received data. The following processing is carried out at the global processing centers: - Check of message quality, reception level, time-tagging, transmitter identification number, sensor message lengths and received frequency value (to compute the location) - Message time-tagging in coordinated universal time (UTC) - Message classification by platform and by chronological order - Data processing All these results are stored and made available to Argos users. Argos users around the world receive data directly in their office or on-site, depending on their choice (email, fax, web, cd-rom, or directly on mapping software). Once the data are received, they are often shared with the scientific community or by the governments or industries that use the data as important management tools.

International cooperation

7 Argos payloads on board of 7 distinct satellites

3 MILLION ARGOS MESSAGES PER DAY

Argos is a unique worldwide location and data collection system dedicated to studying and protecting the environment.

The Argos system was created in 1978 by the French Space Agency (CNES) , the National Aeronautics and Space Administration (NASA) and the National Oceanic and Atmospheric Administration (NOAA), originally as a scientific tool for collecting and relaying meteorological and oceanographic data around the world. In 1986, CNES created a subsidiary, CLS, to operate, maintain and commercialize the system.

The same year, Service Argos, Inc, and North American CLS were created to serve North America user community. Today the two North American companies have merged, forming CLSAmerica.

Currently, several other international space agencies also actively participate in the Argos system including European Organization of the Exploitation o f Meteorological Satellites (EUMETSAT), the Indian Space Research Organization (ISRO) and others.

CNES Founded in 1961, the Centre National d’’ Etudes Spatiales (CN ES) is the government agency responsible for shaping and implementing France’s space policy in Europe. Its task is to invent the space systems of the future, bring space technologies to maturity and guarantee France’s independent access to space. CNES is a pivotal player in Europe’s space program, and a major source of initiatives and proposals that aim to maintain France and Europe’s competitive edge. The Argos program is administered under a joint agreement between the National Oceanic and Atmospheric Administration (NOAA) and the French Space Agency, Centre National d’ Etudes Spatiales (CNES).

NOAA The National Oceanic and Atmospheric Administration (NOAA) is a scientific agency within the United States Department of Commerce focused on the conditions of the oceans and the atmosphere. NOAA warns of dangerous weather, charts seas and skies, guides the use and protection of ocean and coastal resources, and conducts research to improve understanding and stewardship of the environment. The Argos program is administered under a joint agreement between the National Oceanic and Atmospheric Administration (NOAA) and the French Space Agency, Centre National d’ Etudes Spatiales (CNES).

CLS, official operator of the Argos system Collecte Localisation Satellites (CLS) has been providing satellite-based solutions for location and environmental data collection for nearly 30 years. It processes data from nearly 80 instruments on 40 satellites each day. Initially founded by CNES (the French Space Agency) and IFREMER (the French Research Institute for Exploitation of the Sea) to operate and market the ARGOS system, CLS has since added several other services to its offer.

EUMETSAT EUMETSAT is the European operational satellite agency for monitoring weather, climate and the environment. It operates a system of meteorological satellites that observe the atmosphere and ocean and land surfaces. This data is supplied to the National Meteorological Services of the organization’s Member and Cooperating States in Europe, as well as other users worldwide. The primary objective of Argos Advanced Data Collection System (A-DCS) is the collection and dissemination of ocean data.

ISRO The Indian Space Research Organization (ISRO) is the primary space agency of India. ISRO is one of the largest government space agencies in the world. Its primary objective is to advance space technology and use its applications for national benefit. The Satellite with ARGOS and ALTIKA (SARAL) is a joint Indo-French satellite mission for oceanographic studies. SARAL will perform altimetric measurements designed to study ocean circulation and sea surface elevation.