Swedish Navy submarines are to be equipped with enhanced electronic warfare systems from Exelis of the United States.

Exelis said provision of its ES-3701 system comes under a sub-contract from Saab, which was contracted by Sweden's defense procurement agency to modernize its Navy's submarines.

The sub-contract from Saab is worth more than $17 million, the company said.

"The ES-3701 is the ideal ESM system for submarines and surface ships and is widely deployed with allies around the world," said Dave Prater, vice president and general manager of the Exelis radar and reconnaissance systems business. "Our ESM technology will equip Sweden to handle a range of emerging threats they face, now and in the future.

"Our understanding of the threat landscape and our experience has helped make Exelis a leading provider of maritime EW systems that support our customers' critical missions around the world."

The ES-3701 uses a circular array interferometer antenna for precise direction finding over a 360-degree azimuth and at high elevation. Using digital technology and modern signal processing, the system intercepts, measures and identifies complex signals in dense radio frequency environments and despite the presence of interfering signals.

Exelis did not provide a schedule for delivery of the system units to Saab.