The Royal Danish Navy has completed successful sea trials of Thales' SMART-S MKII compact multi-beam Doppler radar aboard the multi-purpose frigate Absalon.

Thales hopes the results will stand it in good stead against its competitors in a bid to upgrade the Royal Navy's Radar Type 996.

The tender forms part of the MoD Maritime Gunnery and Missile Systems Integrated Project Team (MGMS IPT) requirement to upgrade the fleet with a 3D maritime medium-range and target indicator radar system. The contract could have a total value of £80m-£85m.

SMART-S MKII uses digital multi-beam antenna technology and is specifically designed for the coastal environment, eliminating false positives from objects moving on shore that could be mistaken for targets.

SMART-S is a derivative of the SMART-L and S1850M models. It is a multi-beam medium-range search radar consisting of a rotating antenna that also houses the transmit-receive electronics.

Below-deck equipment includes a drive control cabinet and a processing cabinet. The radar is designed to be integrated with the ship's combat system, providing a 3D air and surface picture of the environment.

Powered by 16 powerbooks in parallel, the radar rotates at 27rpm in defence and 13.5rpm in surveillance mode, and a cooling liquid controls temperature.

After factory and acceptance tests, SMART-S was installed in Absalon in March. Sea trials started two months ago and engineering trials are now in progress.

In the control room, a target designation display shows the type, height and direction of the target and whether it is in- or out-bound. It can be fully integrated with other detection systems, with signals processed and displayed alongside CCTV and infrared optometric signals.

Commander Frank Trojahn, Absalon's captain, said: 'SMART-S is designed for coastal warfare, so we carried out tests against aircraft of several different types with varied speeds and behaviours. All were successful.'

SMART-S was also tested against jamming. When it spots jamming behaviours, it changes frequencies and no longer uses the jamming ones.

Signals from SMART-S and other sensors are processed and displayed on widescreen, overhead screens via the Terma Windows- based C-flex command and control system, which gives a common interface for personnel to fine-control the fire control system and radar.

Operations officer Lt-Cdr Tue Lippert, said: 'We particularly liked the fact that SMART-S has two modes — on and off. Our old one had 10 modes, and at any time we were almost certainly in wrong mode.

'As C-flex is based on Windows platform, the crew only needed a three-day crash course. We didn't even need a manual due to its intuitive nature. If anything goes wrong, we can carry out a complete restart in 10 minutes.

'To test a small target, we had two F-16s carry out inbound attack, and we detected them from 62km all the way down to sea level, with automatic tracking kicking in from 59km. Outbound, we tracked them out to 250km at 8km height. Maximum range really is 250km, not just specification.

Thales is bidding for a contract to fit 20 systems in a variety of platforms and two shore facilities, with up to 25 years of support. The first system is due to be operational at sea in 2010, with the final retrofitted system operational no later that 2014.

The remaining bidders are BAE System's Insyte, Lockheed Martin and ELTA.

A Thales spokesman said: 'We think the results of these sea trials will show we have a real, functional product to offer and not just a paper tiger.'