Arexis - High-end Electronic Combat System

Importance of the electromagnetic spectrum

In the course of the last decades, the electromagnetic spectrum has gained enormously in importance. Proprietary and adversary sensors, data radio and other means of communication depend on the use of the electromagnetic spectrum. The availability of sensors and radio data is nowadays essential in order to be able to adequately assess the situation and act in a timely manner. Even a successful deployment of weapons, especially medium and long range weapons, can be determined by the unrestricted use of own sensor technology and data transmission. Accordingly, the usability of the electromagnetic spectrum as well as the prevention of its use by the adversary has become of decisive importance for mission success. It is no longer only an important medium for sensors and data transmission, but at the same time also a contested "space", occasionally even referred to as its own domain.

Technical progress on all sides

Progressive digitalisation, constantly increasing processing power and the latest antenna technologies based on gallium nitride enable an ever more flexible use of the electromagnetic spectrum. In the signature of modern emitters, pulse shapes and used frequencies show almost limitless variations; a classification based on a few parameters is often clearly no longer possible. Older systems are also being digitised and can benefit in terms of sensor accuracy, range and interference immunity.

Requirements for a modern EK self-protection system

Nevertheless, the requirements for an EK self-protection system have not changed; it should continue to provide the crew with a clear situation picture of the electromagnetic spectrum in near real time and be able to effectively ward off imminent threats. However, due to the advancing technological development of potential threats, the effort required to do this successfully has increased to the same extent. Currently used EC self-protection systems are based - simplified - on the principle of recognising signature parameters and their subsequent comparison with databases in order to be able to draw clear conclusions about specific threat systems and operating statuses. The use of such "legacy" systems is already no longer expedient in a moderately modern field of application. This can manifest itself in change displays, so-called ambiguities, or even the non-recognition of emitters. This means that a clear picture of the situation and a warning of imminent threats is no longer possible and poses a considerable threat to personnel, material and the success of the mission.

Saab & EK

For more than 60 years, Saab has been producing - among other things - very powerful electronic warfare systems. In addition to flat hierarchies, innovative thinking and consistent action have led to continuous and successful investment in research and development in the field of electronic warfare. In this way, what was foreseeably necessary was brought to maturity in good time and made available to the market. 

Arexis EK self-protection system

Arexis is Saab's latest generation of electronic warfare systems for flying platforms and represents the current state of the art in a very powerful product family. Arexis was developed to effectively counter the most modern frequency and pulse agile threat systems. The starting point of the development, which took about 8 years, was the already high-performance system of the Gripen C/D (adapted to the Tornado from 2012). The development of such a modern system can cost well over €1 billion. Arexis is used on Gripen E and in the future also on Gripen F, selected modules of the Arexis family are already used on other platforms.

In addition to a very large instantaneous bandwidth, fully digital recording, transmission and processing of signals, highly accurate angular measurement is fundamental to the system's impressive performance in an agile emitter scenario. Although all electromagnetic parameters can be variable, the position of the emitter(s) is a variable that is limited in its agility. Arexis uses interferometry and triangulation to locate emitters very accurately in a very short time, this can be done singularly but also across platforms. The use of Time Difference Of Arrival (TDOA) would also be possible.

Unlike legacy systems, Arexis uses artificial intelligence to detect and classify emitter profiles and operating status. In order to enable subsequent stationary evaluation, it is of course possible to record captured data in scalable granularity. 

Arexis can transmit the acquired situation picture to a wide variety of subsystems of a carrier platform via standardised interfaces. Detailed settings can be made separately and transparently for each interface using mission data. On the active side, state-of-the-art AESA antennas (AESA - Actively Electronically Scanned Array) with the latest gallium nitride technology are used. This is convincing due to its higher power output. Using DRFM (Digital Radio Frequency Memory) and powerful processors, a large number of agile emitters can be effectively jammed or deceived simultaneously. Coordinated ejection of decoys is also freely programmable. Arexis would also be usable for agile, broadband, cross-platform data transmission.

Cooperation with partners

For combat aircraft, Arexis offers the option of including e.g. the on-board radar as an additional sensor and effector. If desired and according to the customer's preference, Arexis can be connected to e.g. electro-optical sensors for missile approach warning. In close cooperation with German industrial partners, the production of e.g. TRMs (transmit/receive modules) could be carried out in Germany, thus securing know-how in the field of a key technology. Through technology in partnership, all relevant systems of the aircraft, which operate in the electromagnetic spectrum, could be operated and controlled from German hands, this ensures the necessary sovereignty in essential capabilities.

Experience with Gripen C/D and Tornado & adaptability of Arexis

The EK self-protection system of the Saab Gripen C/D was successfully adapted to the Tornado of the German Air Force. Despite its advanced age and the difficulty of keeping it in service until its planned replacement in 2030, the Tornado is performing at a high level thanks to Saab's upgraded radar warning system.

The successor system - Arexis - is modular, adaptable and ITAR-free (ITAR - International Traffic in Arms Regulation); communication with other subsystems is ensured via standardised interfaces. The development of Arexis is fully financed and does not have to be passed on to future customers. Therefore, Saab is able to offer Arexis very competitively.

Arexis - survivability, interoperability and alliance capability

In order to be able to continue to make a relevant contribution in alliances or coalitions, it will be necessary to be able to provide modern capabilities in adequate numbers in a sustainable manner. This includes modern capabilities in the electromagnetic spectrum as a contribution to the overall situation as well as a basis for self-protection. However, even with the successful integration of marketable platforms, it appears necessary to modernise further weapon systems in service in order to maintain survivability, interoperability and thus alliance capability. Saab has so far equipped some 4,500 combat aircraft worldwide with electronic warfare systems and therefore has broad expertise in adapting its systems to a wide variety of carrier platforms. Saab is a reliable partner of the Bundeswehr and German industry. Together, a large number of projects have been successfully implemented so far. The renewed order to modernise the radar warning system of the Tornado is further proof of the good cooperation and the trust placed in Saab. In the future, Saab will continue to stand ready as a partner of German industry to adapt Arexis to modern platforms.

Arexis electronic warfare solution

Saab’s Arexis Electronic Warfare (EW) suite delivers crucial situational awareness. Whether fully integrated on-board an aircraft, in a missionised pod, or as payload on an unmanned vehicle, it gives unrivalled defensive and offensive electronic warfare capabilities.

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