SAN ANTONIO, Texas — Harris Corp. and Canada’s exactEarth are establishing a space-based constellation of more than 60 maritime-tracking sensors to enable government and commercial customers to pinpoint the location of ships around the world nearly instantaneously.

Harris announced June 5 at the GEOINT Symposium that the first four sensors, launched in January as hosted payloads on Iridium Next communications satellites, are tracking 250,000 ships through their Automatic Identification System (AIS) beacons. By the end of 2018, when Iridium Communications is scheduled to finish launching its Iridium Next constellation, Harris and exactEarth will be able to notify customers of a ship’s location with an average latency of less than one minute.

That means it will usually take less than one minute from the time a satellite detects an AIS message for the data to pass through the Iridium constellation and ground stations to the customer, David Mottarella, Harris senior manager for maritime geospatial solutions, told reporters June 5.

AIS signals were designed for ship-to-ship communications and the cannot always be detected by satellites. To prevent gaps in coverage, 82 percent of the world will be within view of two AIS sensors and 48 percent will be within view of three. “The more chances I have to collect the data, the better our detection probabilities are going to be,” Mottarella said.

“With 60-plus satellites on orbit, that detection capability is going to be unmatched.”

Harris owns and operates the AIS payloads on Iridium Next satellites and provides AIS products and services to U.S. government customers. exactEArth handles ground-based processing of AIS data and sells AIS products and services to other global customers.

Prior to the January launch of hosted payloads on Iridium Next, exactEarth was tracking ships with AIS sensors on eight small satellites in low Earth orbit.



When the exactEarthRT, which stands for real time, constellation is completed, Harris and exactEarth will be able to notify customers of specific events, such as ship-to-ship rendezvous, ships changing direction, turning off AIS beacons or loitering in prohibited areas. With the new space-based constellation, Harris and exactEarth also will be able to validate a ship’s position even if the vessel is attempting to spoof its geolocation, Mottarella said.