Demo

Amsterdam
Real-Time AIS
Vessel Map

Automatic Identification System Overview

Imagine a shipboard radar or an electronic chart display that includes a symbol for every significant ship within radio range, each with a velocity vector (indicating speed and heading). Each ship “symbol” can reflect the actual size of the ship, with position to GPS or differential GPS accuracy. By “clicking” on a ship symbol, you can learn the ship name, course and speed, classification, call sign, registration number, MMSI, and other information. Maneuvering information, closest point of approach (CPA), time to closest point of approach (TCPA) and other navigation information, more accurate and more timely than information available from an automatic radar plotting aid, can also be available. Display information previously available only to modern Vessel Traffic Service operations centers can now be available to every AIS user as seen below.

HOW AIS WORKS

Each AIS system consists of one VHF transmitter, two VHF TDMA receivers, one VHF DSC receiver, and standard marine electronic communications links (IEC 61162/NMEA 0183) to shipboard display and sensor systems (AIS Schematic). Position and timing information is normally derived from an integral or external global navigation satellite system (e.g. GPS) receiver, including a medium frequency differential GNSS receiver for precise position in coastal and inland waters. Other information broadcast by the AIS, if available, is electronically obtained from shipboard equipment through standard marine data connections. Heading information and course and speed over ground would normally be provided by all AIS-equipped ships. Other information, such as rate of turn, angle of heel, pitch and roll, and destination and ETA could also be provided.

 

AIS normally works in an autonomous and continuous mode, regardless of whether it is operating in the open seas or coastal or inland areas. Transmissions use 9.6 kb GMSK FM modulation over 25 or 12.5 kHz channels using HDLC packet protocols. Although only one radio channel is necessary, each station transmits and receives over two radio channels to avoid interference problems, and to allow channels to be shifted without communications loss from other ships. The system provides for automatic contention resolution between itself and other stations, and communications integrity is maintained even in overload situations.

Each station determines its own transmission schedule (slot), based upon data link traffic history and knowledge of future actions by other stations. A position report from one AIS station fits into one of 2250 time slots established every 60 seconds. AIS stations continuously synchronize themselves to each other, to avoid overlap of slot transmissions. Slot selection by an AIS station is randomized within a defined interval, and tagged with a random timeout of between 0 and 8 frames. When a station changes its slot assignment, it pre-announces both the new location and the timeout for that location. In this way new stations, including those stations which suddenly come within radio range close to other vessels, will always be received by those vessels.

The required ship reporting capacity according to the IMO performance standard amounts to a minimum of 2000 time slots per minute, though the system provides 4500 time slots per minute. The SOTDMA broadcast mode allows the system to be overloaded by 400 to 500% through sharing of slots, and still provide nearly 100% throughput for ships closer than 8 to 10 NM to each other in a ship to ship mode. In the event of system overload, only targets further away will be subject to drop-out, in order to give preference to nearer targets that are a primary concern to ship operators. In practice, the capacity of the system is nearly unlimited, allowing for a great number of ships to be accommodated at the same time.

 

The system coverage range is similar to other VHF applications, essentially depending on the height of the antenna. Its propagation is slightly better than that of radar, due to the longer wavelength, so it’s possible to “see” around bends and behind islands if the land masses are not too high. A typical value to be expected at sea is nominally 20 nautical miles. With the help of repeater stations, the coverage for both ship and VTS stations can be improved considerably.

 

The system is backwards compatible with digital selective calling systems, allowing shore-based GMDSS systems to inexpensively establish AIS operating channels and identify and track AIS-equipped vessels, and is intended to fully replace existing DSC-based transponder systems.

Visible Infrared
Imaging Radiometer
Suite (VIIRS)

The Visible Infrared Imaging Radiometer Suite (VIIRS) is one of the key instruments onboard the Suomi National Polar-Orbiting Partnership (Suomi NPP) spacecraft, which was successfully launched on October 28, 2011. The VIIRS nadir door was opened on November 21, 2011, which enables a new generation of operational moderate resolution-imaging capabilities following the legacy of the AVHRR on NOAA and MODIS on Terra and Aqua satellites. The VIIRS empowers operational environmental monitoring and numerical weather forecasting, with 22 imaging and radiometric bands covering wavelengths from 0.41 to 12.5 microns, providing the sensor data records for more than twenty environmental data records including clouds, sea surface temperature, ocean color, polar wind, vegetation fraction, aerosol, fire, snow and ice, vegetation, , and other applications. Results from the on-orbit verification in the postlaunch check-out and intensive calibration and validation have shown that VIIRS is performing very well.

Night Light Vessel Detections

This layer shows vessels at sea that satellites have detected by the light that they emit at night. This includes all vessels that emit a lot of light at night, The majority of lights detected at sea at night come from commercial fishing vessels. The satellite makes a single over-pass across the entire planet every night, detecting lights not obscured by clouds and designed to give at least one observation globally every day. Because the vessels are detected solely based on light emission, we can detect individual vessels and even entire fleets that are not broadcasting AIS and so are not represented in the AIS-based fishing activity layer. Lights from fixed offshore infrastructure and other non-vessel sources are excluded.

To construct this layer, the Raptor Geo-IoT platform ingests boat detections processed from low light imaging data collected by the U.S. National Oceanic and Atmospheric Administration (NOAA) Visible Infrared Imaging Radiometer Suite (VIIRS). The boat detections are processed in near-real time by NOAA’s Earth Observation Group, located in Boulder, Colorado. The product, known as VIIRS Boat Detections, picks up the presence of vessels using lights to attract catch or to conduct operations at night. More than 85% of the detections are from vessels that lack AIS or Vessel Monitoring System (VMS) transponders. Due to the orbit design of polar orbiting satellites, places closer to polar will have more over-passes per day, while equatorial regions have only one daily. Read more about this product, and download the data here: https://payneinstitute.mines.edu/eog/

 

Southern Anomaly Zone:

 

South Atlantic Anomaly (SAA) is an area where the Earth’s inner Van Allen radiation belt is at its lowest altitude, allowing more energetic particles from space to penetrate. When such particle hit the sensors on board of satellite, it creates a false signal which might cause the VBD algorithm to recognize it as a boat detection. A filtration algorithm has been implemented but more needs to be done to lower the possibility of mis-identification.

 

(see the VIIRS FAQ & https://globalfishingwatch.org/ for more)

Raptor Drifter
Buoy Platform
Overview

40Geo demos two of our drifter buoys “Raptor Buoys” for monitoring the Gulf of Mexico ocean conditions (currents, waves, sea temp…) and to demonstrate the capabilities of the Raptor Geo-IoT Platform (hardware and software).

To find out more about this platform email us at info@40geo.com

WHAT IS A DRIFTER:

  • A drifter, or drifting buoy, is a piece of scientific equipment that collects data on the ocean’s surface. Drifters allow scientists to track ocean currents, changes in temperature, salinity, and other important components of the ocean’s surface as they float freely and transmit information.

  • The technology within a drifting buoy that allows it to gather and share information is powered by batteries in the dome of the buoy. Attached to the dome is a drogue, which resembles a long cylindrical tail, that allows the buoy to be pulled by ocean currents beneath the surface, not just pushed by winds from above. For a better understanding of the structure of drifters, visit the “Dissect a Drifter” page!)

These drifters are a platform for a host of sensors for scientific monitoring.

  • Sea Temp

  • Wave Height

  • Direction Heading

  • AIS (Optional)

  • Many other sensor configurations

Raptor Drifter Buoys communicate in real-time via the Iridium satellite constellation. The Iridium satellite constellation is a system of 66 active communication satellites and spares around the Earth. It allows worldwide voice and data communications using handheld devices. The Iridium network is unique in that it covers the whole earth, including poles, oceans and airways.

Our Drifter Platform:

Amsterdam
Real-Time AIS
Vessel Map

Automatic Identification System Overview

Imagine a shipboard radar or an electronic chart display that includes a symbol for every significant ship within radio range, each with a velocity vector (indicating speed and heading). Each ship “symbol” can reflect the actual size of the ship, with position to GPS or differential GPS accuracy. By “clicking” on a ship symbol, you can learn the ship name, course and speed, classification, call sign, registration number, MMSI, and other information. Maneuvering information, closest point of approach (CPA), time to closest point of approach (TCPA) and other navigation information, more accurate and more timely than information available from an automatic radar plotting aid, can also be available. Display information previously available only to modern Vessel Traffic Service operations centers can now be available to every AIS user as seen below.

HOW AIS WORKS

Each AIS system consists of one VHF transmitter, two VHF TDMA receivers, one VHF DSC receiver, and standard marine electronic communications links (IEC 61162/NMEA 0183) to shipboard display and sensor systems (AIS Schematic). Position and timing information is normally derived from an integral or external global navigation satellite system (e.g. GPS) receiver, including a medium frequency differential GNSS receiver for precise position in coastal and inland waters. Other information broadcast by the AIS, if available, is electronically obtained from shipboard equipment through standard marine data connections. Heading information and course and speed over ground would normally be provided by all AIS-equipped ships. Other information, such as rate of turn, angle of heel, pitch and roll, and destination and ETA could also be provided.

 

AIS normally works in an autonomous and continuous mode, regardless of whether it is operating in the open seas or coastal or inland areas. Transmissions use 9.6 kb GMSK FM modulation over 25 or 12.5 kHz channels using HDLC packet protocols. Although only one radio channel is necessary, each station transmits and receives over two radio channels to avoid interference problems, and to allow channels to be shifted without communications loss from other ships. The system provides for automatic contention resolution between itself and other stations, and communications integrity is maintained even in overload situations.

Each station determines its own transmission schedule (slot), based upon data link traffic history and knowledge of future actions by other stations. A position report from one AIS station fits into one of 2250 time slots established every 60 seconds. AIS stations continuously synchronize themselves to each other, to avoid overlap of slot transmissions. Slot selection by an AIS station is randomized within a defined interval, and tagged with a random timeout of between 0 and 8 frames. When a station changes its slot assignment, it pre-announces both the new location and the timeout for that location. In this way new stations, including those stations which suddenly come within radio range close to other vessels, will always be received by those vessels.

The required ship reporting capacity according to the IMO performance standard amounts to a minimum of 2000 time slots per minute, though the system provides 4500 time slots per minute. The SOTDMA broadcast mode allows the system to be overloaded by 400 to 500% through sharing of slots, and still provide nearly 100% throughput for ships closer than 8 to 10 NM to each other in a ship to ship mode. In the event of system overload, only targets further away will be subject to drop-out, in order to give preference to nearer targets that are a primary concern to ship operators. In practice, the capacity of the system is nearly unlimited, allowing for a great number of ships to be accommodated at the same time.

 

The system coverage range is similar to other VHF applications, essentially depending on the height of the antenna. Its propagation is slightly better than that of radar, due to the longer wavelength, so it’s possible to “see” around bends and behind islands if the land masses are not too high. A typical value to be expected at sea is nominally 20 nautical miles. With the help of repeater stations, the coverage for both ship and VTS stations can be improved considerably.

 

The system is backwards compatible with digital selective calling systems, allowing shore-based GMDSS systems to inexpensively establish AIS operating channels and identify and track AIS-equipped vessels, and is intended to fully replace existing DSC-based transponder systems.

Visible Infrared
Imaging Radiometer
Suite (VIIRS)

The Visible Infrared Imaging Radiometer Suite (VIIRS) is one of the key instruments onboard the Suomi National Polar-Orbiting Partnership (Suomi NPP) spacecraft, which was successfully launched on October 28, 2011. The VIIRS nadir door was opened on November 21, 2011, which enables a new generation of operational moderate resolution-imaging capabilities following the legacy of the AVHRR on NOAA and MODIS on Terra and Aqua satellites. The VIIRS empowers operational environmental monitoring and numerical weather forecasting, with 22 imaging and radiometric bands covering wavelengths from 0.41 to 12.5 microns, providing the sensor data records for more than twenty environmental data records including clouds, sea surface temperature, ocean color, polar wind, vegetation fraction, aerosol, fire, snow and ice, vegetation, , and other applications. Results from the on-orbit verification in the postlaunch check-out and intensive calibration and validation have shown that VIIRS is performing very well.

Night Light Vessel Detections

This layer shows vessels at sea that satellites have detected by the light that they emit at night. This includes all vessels that emit a lot of light at night, The majority of lights detected at sea at night come from commercial fishing vessels. The satellite makes a single over-pass across the entire planet every night, detecting lights not obscured by clouds and designed to give at least one observation globally every day. Because the vessels are detected solely based on light emission, we can detect individual vessels and even entire fleets that are not broadcasting AIS and so are not represented in the AIS-based fishing activity layer. Lights from fixed offshore infrastructure and other non-vessel sources are excluded.

To construct this layer, the Raptor Geo-IoT platform ingests boat detections processed from low light imaging data collected by the U.S. National Oceanic and Atmospheric Administration (NOAA) Visible Infrared Imaging Radiometer Suite (VIIRS). The boat detections are processed in near-real time by NOAA’s Earth Observation Group, located in Boulder, Colorado. The product, known as VIIRS Boat Detections, picks up the presence of vessels using lights to attract catch or to conduct operations at night. More than 85% of the detections are from vessels that lack AIS or Vessel Monitoring System (VMS) transponders. Due to the orbit design of polar orbiting satellites, places closer to polar will have more over-passes per day, while equatorial regions have only one daily. Read more about this product, and download the data here: https://payneinstitute.mines.edu/eog/

 

Southern Anomaly Zone:

 

South Atlantic Anomaly (SAA) is an area where the Earth’s inner Van Allen radiation belt is at its lowest altitude, allowing more energetic particles from space to penetrate. When such particle hit the sensors on board of satellite, it creates a false signal which might cause the VBD algorithm to recognize it as a boat detection. A filtration algorithm has been implemented but more needs to be done to lower the possibility of mis-identification.

 

(see the VIIRS FAQ & https://globalfishingwatch.org/ for more)

Raptor Drifter
Buoy Platform
Overview

40Geo demos two of our drifter buoys “Raptor Buoys” for monitoring the Gulf of Mexico ocean conditions (currents, waves, sea temp…) and to demonstrate the capabilities of the Raptor Geo-IoT Platform (hardware and software).

To find out more about this platform email us at info@40geo.com

WHAT IS A DRIFTER:

  • A drifter, or drifting buoy, is a piece of scientific equipment that collects data on the ocean’s surface. Drifters allow scientists to track ocean currents, changes in temperature, salinity, and other important components of the ocean’s surface as they float freely and transmit information.

  • The technology within a drifting buoy that allows it to gather and share information is powered by batteries in the dome of the buoy. Attached to the dome is a drogue, which resembles a long cylindrical tail, that allows the buoy to be pulled by ocean currents beneath the surface, not just pushed by winds from above. For a better understanding of the structure of drifters, visit the “Dissect a Drifter” page!)

These drifters are a platform for a host of sensors for scientific monitoring.

  • Sea Temp

  • Wave Height

  • Direction Heading

  • AIS (Optional)

  • Many other sensor configurations

Raptor Drifter Buoys communicate in real-time via the Iridium satellite constellation. The Iridium satellite constellation is a system of 66 active communication satellites and spares around the Earth. It allows worldwide voice and data communications using handheld devices. The Iridium network is unique in that it covers the whole earth, including poles, oceans and airways.

Our Drifter Platform: