Programme Focus: KORA-40 for Germany’s New Frigates

F-126 class frigate
An artist’s impression of the German Navy’s new ‘F-126’ class frigates. These ships will be outfitted with Rohde & Schwarz’ KORA-40 electronic warfare system.

Development is moving ahead on the electronic warfare system destined to equip new frigates for the German Navy.

The Deutsche Marine (German Navy) will receive new frigates from circa 2028. Up to six ‘F-126’ class ships could replace the fleet’s existing ‘F-125/Baden-Württemberg’ class frigates. The new ships will include the latest iteration of Rohde & Schwarz’ KORA naval electronic warfare system.

The company was awarded the contract in late September 2021 to provide the KORA-40 combined Electronic Support Measure/Electronic Countermeasure (ESM/ECM) for the new frigates. KORA-40 is an evolution of the KORA-18 system equipping the F-125 ships. The ‘40’ suffix refers to the system’s 40GHz upper frequency limit.

Armada recently visited Rohde & Schwarz’ facilities in Munich, southern Germany, and was briefed on the KORA-40 and its capabilities. Company officials discussed the system’s overall design philosophy. Automation is key and officials said that diminishing naval crew sizes are emphasising this trend. As a means of comparison, open sources say the F-125 frigates have a complement of circa 190. This reduces to 110 for the new ships.

Hypersonic Threats

The emphasis on automation dovetails with similar emphases on fast reaction times and high probabilities of signal interception. The advent of hypersonic missiles like Russia’s 3M22 Zircon (NATO reporting name SS-N-33) is instructive. The 3M22 may reach speeds of at least Mach-5, the standard definition for hypersonic velocities. This translates into speeds of 3,333 knots (6,174 kilometres-per-hour). An ESM antenna mounted 40-metres (131-feet) above the waterline would detect such a missile following a sea-skimming trajectory at a range of circa 14 nautical miles (26 kilometres). The time between detection and impact would be around 15 seconds. During this time the ship would need to recognise, confirm and track the threat, and initiate soft- and hard-kill countermeasures.

Moreover, AShMs increasingly employ Millimetric Wave (MMW) radar seekers. Using frequencies above 30GHz, MMW radars produce exceptionally sharp pictures of their target. This improves the missile’s accuracy compared to radar seekers using X-band (8.5GHz to 10.68GHz). Encompassing wavebands up to 40GHz will ensure the KORA-40 detects such threats.

KORA-40 Architecture

Rohde & Schwarz officials continued that development of the 40GHz capability for the KORA-40 is “more or less complete”. The company is planning to offer KORA-40 for export, although it will be given a different name. The KORA-40 moniker only refers to those systems equipping the German Navy. The export version will also include some unspecified differences. These almost certainly relate to aspects of the systems’ performance or architecture unique to German Navy requirements.

Furthermore, customers will be able to choose from between one and three modules for their system, each of which provides differing levels of capability and performance. Two ESM modules cover a 500 megahertz/MHz to 40GHz waveband. Another covers a two gigahertz to 18GHz waveband. Customers can opt for a single module or procure all three. Officials continued that they are also looking at adding a communications ESM function to cover high frequency (three megahertz/MHz to 30MHz) wavebands.

As the KORA-40 gathers both communications and electronic intelligence, track data on both can be fused and depicted by the ship’s combat management system. The KORA-40’s sensitivity makes it possible to discriminate between platforms separated by very short distances, officials added.


Rohde & Schwarz already has an evolution plan in place for the KORA-40. Officials divulged that this could see capabilities added to help declutter heavily congested electromagnetic environments. These will be increasingly found in littoral areas as fifth-generation (5G) wireless protocols are rolled out globally. The profusion of devices and subscribers heralded by 5G will increasingly congest areas like coastlines where signal of interests from a naval radar or radio could hide. Likewise, the company “is looking at cognitive approaches for naval ESMs”. However, it does “not consider these market-ready at the moment”.

by Dr. Thomas Withington