Surveillance at sea

Radar designed to detect ships beyond the curvature of the earth uses a new tracking system developed in Brazil

A state-of-the-art radar capable of detecting and identifying ships at sea beyond the curvature of the horizon is already operating off the southern coast of Brazil. Created by São Paulo–based company Iacit Soluções Tecnológicas, the OTH (Over the Horizon) radar is installed at the Albardão lighthouse, a remote Navy site located about 100 kilometers (km) from the border with Uruguay. The device, the first of its kind in South America, was designed to give Brazil more independence to control and monitor its maritime borders and territory. It is already being used to monitor the Blue Amazon, a maritime area of ​​4.5 million square kilometers (km2) demarcated by the Brazilian continental shelf, and an exclusive economic zone that is rich in natural and mineral resources, such as pre-salt oil reserves.

“Few nations in the world, possibly only the United States, China, Russia, the United Kingdom, Australia, and Canada, have the know-how to design and build these radars,” says electrical engineer Gustavo de Castro Hissi, director of design at Iacit, whose headquarters are based in São José dos Campos (see Pesquisa FAPEPSP issue no. 250). Made in partnership with the Brazilian Navy, the OTH radar is able to monitor naval traffic (military, cargo, passenger, and fishing boats, etc.) more than 200 nautical miles from the coast (about 370 km) and is ideal for detecting noncooperative vessels—those that do not transmit an Automatic Identification System (AIS) signal. It is also capable of monitoring ships beyond the horizon. The radar on the Rio Grande do Sul coast belongs to Iacit, which plans to sell it to the Navy.

Conventional radars have a much smaller range of approximately 70 km and use electromagnetic waves that follow a linear path and can only identify targets within their field of vision, making them ineffective beyond the curvature of the Earth. The OTH radar, on the other hand, uses a signal that follows the surface of the ocean, attracted by the salinity of the water, and can travel over much longer distances. Each radar is capable of monitoring an area of ​​144,000 km2 off the Brazilian coast.

IACIT Radar transmission antenna (foreground) at the Albardão lighthouse, a Navy area located on the coast of Rio Grande do SulIACIT

Navy interest
Admiral Paulo José Rodrigues de Carvalho, former chief of staff at the Brazilian Naval Operations Command Center, believes the Iacit radar can be useful for patrolling the coast. “The OTH is a direct contribution to the Navy’s ambitious maritime surveillance project, the Blue Amazon Management System [SISGAAZ]. With just four devices it is possible to monitor all of the oil and gas deposits in the Campos and Santos basins off the coasts of Rio de Janeiro and São Paulo,” he says. At the end of March, Iacit presented the equipment to leaders of the Brazilian Navy. “We are in discussion with the Navy and we expect them to be the first to use the radar,” Hissi said, noting that about 14 units would be needed to monitor the entire Brazilian coast—the company has chosen not to disclose the price of the equipment.

Development of the OTH radar began in 2011 and over 80% of its components are produced in Brazil. “The tracking subsystem was the last element to be finalized by our team, providing a visual image of boat locations and movements. The device was completed this year,” he says. Funded by the FAPESP Technological Innovation in Small Businesses program (PIPE), the tracker links consecutive detections of the same target to deduce information such as direction and speed. Without this feature, it would only be able identify points on the map, rather than showing where ships have come from and where they are going.

Operators can use this tracking information to analyze whether two vessels are on a collision course, for example, as well as for monitoring the behavior of suspicious targets. Tracking the path taken by a target can help identify ships carrying smuggled goods or fishing in prohibited areas—the aforementioned noncooperative vessels.

IACIT Radar screen shows boats (green squares) sailing off the coast of Rio Grande do Sul in an area monitored by the device. The blue dashed lines show their trajectoriesIACIT

National processor
The next challenge for Iacit is to start domestic production of the signal processor, a vital component of the radar and the only part that is still imported. Its function is to transform the echo reflected by the vessels and captured by the 23 antennas of the OTH into a detection map, showing the location of each ship. The processing subsystem used by the radar at the Albardão lighthouse was provided by Israeli company Elta, which has a technological cooperation agreement with Iacit.

“Just like the tracker, designing and building the signal-processing system is no trivial task. We have already completed the processing algorithm, which has proven fully functional in laboratory tests, and now we need to continue with the systems engineering stages, which include integrating the algorithm into the hardware and conducting tests internally and in the field,” says Hissi. The new processor is expected to be ready within 18 months.

Iacit is using its own resources to move production of the signal-processing subsystem into Brazil, but the company is seeking external funding to accelerate its development. According to company president Luiz Carlos Teixeira, the Israeli processor was used in the first OTH radar to speed up production. “It significantly reduced the amount of time needed to finish the radar,” says Teixeira, adding that the logistical support provided by the Navy, who allowed the company to use the Albardão lighthouse, was also fundamental to the project.

Tactical tracking for surveillance radars – IHM-T (no. 15/50596-2); Grant Mechanism Technological Innovation in Small Businesses (PIPE); Principal Investigator Gustavo de Castro Hissi (Iacit); Investment R$366,904.61.