The NATO Undersea Research Centre (NURC) is extending its range of echo repeaters to include moored and AUV-mounted variants. Alain Maguer, a NURC representative, told the Undersea Defence Technology conference in Alicante, Spain that the organisation is testing prototypes of the NURC Echo Repeaters (NERs), and in July is conducting testing for the moored variant.
'In 2011 we decided to develop a new echo receiver, the Moored Echo Receiver,' Maguer said. 'This is a unique system that will be tested in July and then again in September for a month.' Maguer noted that the system is powered on high-efficiency lithium cells.
Testing comes under the main ASW programme within NURC, which involves conducting at-sea experiments for developing and evaluating new systems that are set to replace the use of actual targets by providing an artificial target that returns a synthetic echo.
NURC is currently working on an underwater AUV variant, and it has some 15 AUVs that it wants to work on with this repeater. 'The system will be easily integrated into an AUV, and testing was conducted in 2011, 2012 and will again in 2013. We've been demonstrating active multi-static ASW against a target,' Maguer explained. The receiver ranges over four octaves and is 31mm in diameter.
'We've been trying to use COTS systems. It really is nothing fancy.' The NER will also be used by the Italian Navy for its Frégate Multi-Mission (FREMM) programme's sonar sea tests: 'We will provide them with a copy of this system by the end of the year.'
NURC-developed software is used on the platforms. 'We have been doing a lot of calibration on the systems while at sea,' Maguer said.
Challenges in developing this technology include discriminating targets from clutter and long-range communications. NURC is looking at distances of kilometres, so the systems are low frequency but long distance.
'It's very easy to be operational at sea. We're very happy to provide it to the navies,' Maguer concluded. 'We are currently investigating what could be the maximum speed. We're getting very good data.'