The threat posed by low-flying, low-speed, small-sized drones is becoming a reality in combat and national security scenarios
As this threat becomes more serious, NATO has recently conducted several studies on this topic. In previous years, two studies were published under the codes SG-170 and SG-188, and in 2017 the Industrial Advisory Group conducted the latest study to date and published it under the title SG-200 "Study on Low, Slow and Small Threat Effectors." (Investigation of low-speed, low-flying, small-sized enemy executive means). In all of these reports, the researchers come to the main conclusion that no single sensor type alone can offer sufficient tracking and identification capabilities in order to provide reliable and effective protection against the threat of low-flying, low-speed, small-sized drones (HNM-UAVs). At the same time, it is necessary to take into account that the swarm capabilities of unmanned vehicles are already very close, after which the fight against them will become significantly more complicated.
A new market on the horizon
The number of companies operating in the anti-drone systems market is constantly growing. MarketForecast.com recently published an analytical report, "Global Counter UAV (C-UAV) Systems Market Forecast to 2026," which predicts two scenarios, one without significant events and one with a successful UAV attack. In the first case, the commercial market should grow from $ 123 to 273 million at a compound annual growth rate of 10.5%, while the military market should grow from $ 379 to $ 1223 million at a compound annual growth rate of 15.8%. In the case of the UAV attack, the peak of purchases will occur in the first years, and then there will be some decline. In any case, the data for both scenarios show significant market gains.
As noted, one sensor is not able to cope with the HNM-UAV threat. Thus, it is necessary to use different types, as a rule, these are radar stations, radio receivers, acoustic and optical sensors. Threat neutralization can take many forms. The first is a functional defeat with the use of intentional jammers, disorienting jamming stations, which give the wrong direction to a drone operating on a GPS signal or intercept its controls. The second is direct damage using lasers, high-energy microwaves, physical barriers, or even solid damaging elements of various types.
For ready-made systems
Leaving aside systems designed to neutralize tactical and larger drones, which can already be considered as part of a very short-range air defense system, we will focus on systems designed to combat low-level UAVs (often off-the-shelf commercial systems) that guarantee their neutralization by short and medium distances. According to industry sources, the average detection range of NNM-UAV-type targets for modern radars is 8 km, tracking range 5 km, while optoelectronic systems have a detection range of 8 km and a tracking range of 4 km.
As for the actuators, radio frequency systems can detect the drone at a distance of 8 km, disrupt its operation at 2.5 km and effectively jam at a distance of about 2 km, while lasers and an electromagnetic pulse can be used at a distance of 1.5 km. By simplifying and taking into account that these systems can be used both in military operations and in security scenarios, we can divide anti-drone systems into medium and short-range systems. The former, as a rule, are stationary or installed on vehicles and provide a "safe dome" at the aforementioned ranges. Short-range systems usually come in the form of "radio frequency guns" that can be used for object defense, their effectiveness in preventing damage depends on the type of payload carried by the drone itself.
Let's start with medium-range systems, although in some cases it is difficult to categorize a particular system, since the developer offers many different options with different characteristics based on it. France's Thales is definitely one of those companies, offering a variety of modular and scalable solutions while taking full advantage of its integration capabilities.
Let's talk about AUDS
If we talk about current systems, then first of all it is worth starting with the AUDS (Anti-UAV Defense Solution) system, developed by three British companies that have combined their experience in one comprehensive solution.
Frequency Modulated CW Doppler radar operates in electronic scanning mode and provides 180 ° azimuth and 10 ° or 20 ° elevation coverage, depending on configuration. It operates in the Ku band and has a maximum operating range of 8 km, can determine the effective scattering area (ESR) up to 0.01 m2. The system can simultaneously capture several targets for tracking.
The Chess Dynamics Hawkeye Surveillance and Search System is installed in the same unit with an RF jammer and consists of a high-resolution optoelectronic camera and a cooled medium-wave thermal imager. The first has a horizontal field of view from 0.22 ° to 58 °, and a thermal imager from 0.6 ° to 36 °. The system uses a digital tracking device Vision4ce, which provides continuous tracking in azimuth. The system is capable of continuously panning in azimuth and tilting from -20 ° to + 60 ° at a speed of 30 ° per second, tracking targets at a distance of about 4 km.
The ECS Multiband RF Silencer features three integrated directional antennas that form a 20 ° beam. The company has gained extensive experience in the development of technologies for countering improvised explosive devices. A company representative told about this, noting that several of its systems were deployed by coalition forces in Iraq and Afghanistan. He added that ECS knows the vulnerabilities of data transmission channels and how to use it.
The heart of the AUDS system is the operator control station, through which all system components can be controlled. It includes a tracking display, a main control screen, and a display for viewing videos.
In order to expand the surveillance area, these systems can be networked, whether it is several full-fledged AUDS systems or a network of radars connected to a single “surveillance and search system / jammer” unit. Also, the AUDS system can potentially be part of a larger air defense system, although the companies do not intend to develop this direction yet.
AUDS is available in three configurations: a portable rooftop platform, a rugged mast system for forward operating bases or temporary camps, and a fixed system for border and critical infrastructure security. AUDS can also be installed on vehicles and is optimized and hardened for use on military trucks or commercial vehicles. The system was deployed to units of the US Army in 2016, and reached the highest level of technological readiness in January 2017.
The German company Rheinmetall approaches the problem of countering drones from a slightly different position, since it mainly takes into account more advanced threats, for example, advanced drones that can avoid detection by radio frequency means, to combat which one or another ground-based air defense system is needed to guarantee their detection and neutralization. Thus, Rheinmetall uses a wide variety of systems from its extensive portfolio as anti-target solutions. The company has already won two major contracts to supply the Radshield family of systems for the protection of prisons in Switzerland and Germany, which may include various modules that can be customized to suit the needs of the customer.
Among them we will find the UIMIT (Universal Multispectral Information and Tracking) optoelectronic surveillance kit, which includes 12 TV cameras and 8 infrared sensors, covering a 360 ° sector and stabilized in three axes. The kit can be supplemented with an infrared cooled FAST search and tracking sensor with a 360 ° view and a refresh rate of 5 frames per second, as well as radars with AFAR Oerlikon MMR (Multi Mission Radar) with a field of view in azimuth of 90 ° and in elevation of 80 °. Decision making is carried out with the participation of the SC2PS (Sensor Command & Control Software) operational control software complex, which is available for various command levels, from personal to national.
Rheinmetall also offers executive systems, ranging from revolving or twin 35-mm cannons capable of firing AHEAD air blast ammunition (the possibility of developing a 30-mm single-shot AHEAD cannon is being considered) and ending with HEL (High Energy Laser) laser systems, which have now reached technological readiness level 6 (technology demonstration). One level below (technology development stage) is the reusable Sentinel flying interceptor developed by the Swiss company Skysec. The Sentinel has a length of 700 mm and a wingspan of 300 mm and weighs 1.8 kg. A homing head is installed in the bow, and behind it is an electric motor, which drives the bow propeller, which makes it possible to reach a speed of 230 km / h; the range of the device is up to 4 km. The Sentinel device is launched with the loaded approximate three-dimensional coordinates of the desired drone, when approaching it, it throws out a net, capturing a hostile drone, after which the captive is dropped to the ground with the help of a parachute; as a consequence, indirect damage is reduced to zero.
More German solutions
Rheinmetall offers other executive systems as well. For example, the HPM (High Power Microwave) system, also used to neutralize improvised explosive devices (IEDs), as well as a 9-mm multi-barreled cannon with a rate of fire of 1500 rounds per minute, capable of firing a burst of 30 rounds; Moreover, each projectile generates a cloud of plastic submunitions that, when dropped to the ground, have a minimum residual energy of less than 0.1 J / mm2. In addition to military applications, Rheinmetall, together with the Austrian company Frequentis, specializing in communications and information systems, offers its systems for the protection of airports.
The German company Hensoldt, spun off in 2017 from the defense electronics business of the European giant Airbus, has developed the Xpeller system, which consists of its own functional blocks. The system includes a Spexer 500 X-band radar with a 120 ° azimuth and 30 ° elevation sector and a typical detection range of 4 km, a NightOwl ZM-ER module with a color camera and a 3-5 μm thermal imager, and equipped with omnidirectional or directional antennas jamming device with rated power from 10 to 400 W, operating in the range of 20-6000 MHz.
In May 2017, to further enhance Xpeller's detection capabilities, the company signed an agreement with Norway's Squarehead Technology to integrate the Discovair acoustic sensor. This system, based on an array of 128 acoustic microphones, also has a signal processor.
Another German solution, called Guardion, combines components from three different companies. ESG's Taranis control component, combining and analyzing all sensor data, visualizes the approaching drone and monitors the situation. Rhode & Schwarz has provided the Ardronis RF detection system, which detects the remote control radio channels of commercial drones. A radar signal receiver, optocoupler and acoustic sensors can be added to the system. Ardronis also works as an actuator, since it can disrupt the operation of radio channels, as well as the navigation satellite system, while the R&S Wi-Fi Disconnect subsystem allows detecting and disrupting the Wi-Fi signal used to control the drone.
Diehl Defense provided the HPEM direct engagement component. This scalable system is capable of burning out drone electronics thanks to an electromagnetic pulse from a range of several hundred meters, and is also capable of fighting swarm attacks. The only known application of the Guardion system is its deployment at the July 2017 G20 Summit in Hamburg, as ESG received the task of protecting the sites of this summit from the Federal Criminal Police Office.
Developers from Italy, Israel and Turkey
The Italian company Leonardo has developed the Falcon Shield complex, which combines radar, for example, Lyra 10, an optoelectronic kit, for example, Nerio-ULR, and electronic jammers to neutralize unwanted drones. For its part, IDS (Ingegneria Dei Sistemi) has developed an integrated Black Knight system based on Doppler radar, a medium-range optoelectronic system with television and infrared cameras and a multi-band jammer. The system can be expanded by adding other sensors, for example, three-band direction finders. Elettronica has developed the Adrian system, capable of detecting outgoing and descending signals from aircraft and ground operators, classifying, identifying and determining their coordinates thanks to an extensive library that the user can constantly replenish, as well as disrupt the operation of threats through smart jamming algorithms. Both systems were field tested in 2017. IDS and Elettronica are currently working with Leonardo to meet the needs of the Italian Air Force, developing an integrated system, the information on which is still classified.
The Turkish company Aselsan has developed two systems: installed on Gergedan-UAV machines and stationary Ihtar. The first is a programmable jamming system with over 100 different jamming patterns. RF spectrum is customer specific, standard antenna is omnidirectional, but directional antennas are optional. With a Gergedan-UAV system weighing 65 kg, the RF output power is less than 650 W, the battery life is one hour.
In the Ihtar stationary system, the Gergedan system is used as an actuating element, to which the Asag Ku-band radar is added, capable of detecting mini-UAVs in a sector of more than 360 ° at a distance of 5 km; sector scan is also available. In addition, an optoelectronic unit can be added, usually mounted on a stabilized HSY platform, on which the Asag radar itself can also be installed. Both systems were sold to several countries in the Middle East, and at the end of 2017, the Ihtar system was installed to guard a facility in Indonesia. As for the local market, the Gergedan-UAV system has been installed on many VIP vehicles, while Ihtar has been installed on several military bases.
At the end of 2017, the Israeli government set up a national task force within the Air Force to deal with security and counter-drones. However, the national industry already offers numerous solutions in this area. Rafael has developed a tripod-mountable Drone Dome system that combines sensors from various companies with Rafael actuators and controls. Detection is provided by the Rada Rada multitasking hemispherical radar RPS-42, which is capable of detecting an object with an RCS of 0.002 m2 at a distance of 3.5 km, in combination with the NetSense COMINT radio intelligence system from Netline, operating in the range from 20 MHz to 6 GHz, which detects signals even before the drone takes off, providing azimuth thanks to antennas with a field of view of 60 degrees.
Responsible for identification is the Controp MEOS optoelectronic unit, which includes a daytime CCD camera with x50 magnification and a third generation thermal imaging camera. Rafael's automated control system integrates all sensors, and its algorithms provide all the necessary information to the operator, who can neutralize an approaching object using the Netline C-Guard jamming system, which operates on five channels in the range from 433 MHz to 5.6 GHz. With this configuration, the system is expected to ship in mid-2018.
