General Information

General Information

Detection methods


Due to the specificity of the needs of recipients of these types of solutions and the different types of areas to be protected, it is good to know the characteristics of each detection method.

The type of detectors used, their technical parameters, their impact of the environment on which the device is operating (atmospheric factors, time of day (eg. at night), interaction with nearby devices (eg, audio disturbances) determines the information that we expect from the detector such as: occurrence of the intruder, number of false alarms, and often the possibility of detector’s operation.

Below is a description of the method used to detect drones, along with their characteristics.

 


  Audio Detection

How it works

It consists of detecting characteristic infrasound frequencies. They are emitted, for example, by the rotation of the propellers, and collected by the system in the form of digital interpretation of acoustic signals (PCM – Pulse Code Modulation). These are acoustic signatures. The more signatures in the software base of the device, the more accurately the drone can be identified.

 

Characteristics of solutionsCharakterystyka rozwiązań

The small amplitude of the sound emitted by the drones, as well as the often occurring background sound, affects the detection distance. Usually, it is around 50m with medium external noise as an additional background noise.

 


  Wideo Detection

How it works

This involves capturing the subject's movement on the background of a static image (a terrain image). There are a lot of motion detection algorithms.

 

Characteristics of solutions

The problem is primarily the small difference in contrast between the drone and the background, and the size of the drone in relation to the size of the image.

It’s worth noting that with the fixed lens focal length of the camera at longer distances, the drone image occupies a smaller portion of the camera's transmitter (fewer pixels of the image). In extreme cases, it may be one pixel. Of course, you can use lenses with variable focal length. However, at high focal lengths, the camera is very narrow both vertically and horizontally, so the field of view is reduced (but it increases the distance from the transmitter). With large lens focal lengths, it is very difficult to maintain system stability, which causes the whole image to be mobile and to have no fixed points, it can also be blurred and out of focus. This makes it impossible to recognize or identify.

Automatic detection of the drone by the device using a camera as the only detector is currently around 100m. It is not about the observation of an already detected drone, which can be carried out from a further distance.

However, cameras such as CCTV can be a very useful tool for identifying an already reported alarm.

 


  Thermal Imaging

How it works

This is a thermal image of the object being observed. The amount of heat produced by the flying vessel depends on the type of propulsion used. Many heavy duty drones are powered by internal combustion engines that are perfectly visible to the thermal imager.

 

Characteristics of solutions

The detection distance by using CCTV or thermovision is associated with motion detection procedures implemented in the cameras and a lack of contrast enhancement procedures. After working out the appropriate procedures, this distance will increase. At this moment, the algorithms used for recognizing a dynamically changing image are too weak to detect an image of a drone (which is small in relation to the rest of the image) to determine that it is in fact a drone. In additon, the problem is the necessary "quantity" of contrast to detect such dones against a dark or bright background image.

 


  Radar

How it works

The obvious way of detecting flying objects for years has been radar. Radio waves bounce off differently depending on the wavelength, shape, and effective surface of the object's reflection. The radar search area is the maximum and minimum detection distance and the width of azimuth angle and angle of the elevation.

 

Characteristics of solutions

For the radar, it is crucial to know about the minimum effective reflective surface of objects that can be detected by it (Radar Cross Section). The larger the surface of an object's effective reflection, the better it echoes the waves, which gives you a stronger echo. Unfortunately, drones are devices that have very small RDS.

 

It is also necessary to define the user's needs accurately in the context of analysing the environment in which the device is to operate. For instance, the type of terrain (whether or what are obstacles), the required search area (both maximum and minimum), the influence of wavelength on living organisms, the number of false alarms. 

 

In the case of detection of such small objects such as a drone, the problem is the impact / harmfulness of the very short wave applied to living organisms, as well as the detection of a large number of objects, and thus the number of false alarms.The advantage may be the large detection distance for bigger devices.

 


  Radio waves

How it works

Civil drones can fulfil their tasks by using radio communications in their available bands. It is used not only for communications and operator commands, but also for other functions needed to ensure the operation of the device.

 

Characteristics of solutions

Nowadays, this is the basic way of controlling such devices. By detecting the radio signal outside the droning alarm, there is the possibility of obtaining other sensitive information, for example: approximate position of the object (for a narrow group of drones, even GPS coordinates), identification of device type. Depending on the type of detector used, the detection distance is now over 1000m.The problem is the possibility of false alarms. Most often, these are mistakes connected with the misinterpretation of signals coming from other than device drones.

 

While the use of drone detection devices in this way is completely in accordance with the law, other activities that interfere with frequency operations are not.

 

 

Summary

Knowing the different detection methods will allow you to tailor technical solutions to your specific security needs and the type of protected area or building.

 

The key thing here is to present a ready-to-use solution, and simulate real-world situations in a real environment. These should be the deciding factors for choosing a drone detector.

 

 

Counteraction

Determining needs

Counteracting drones takes on different variants depending on the needs and expectations of a given entity. A list of basic elements that should be determined before choosing a solution:

 

  • Reach range and reaction time

These two factors are most often taken into account when planning protection against drones. However, setting these parameters is only the beginning of selecting the right device.

 

Commonly used simulations to test such features is to fight two drones, which are coming simultaneously from opposite directions. It is worth using different flying models with different control types.

 

  • Types of civilian drones that the system is supposed to defend the area from

This is equally important because very often the type of parameters (eg communication) and the manner of movement of the drone (eg speed) effectively eliminate some of the widely presented ways of fighting with drones.

 

  • Ease of use

Counter-measure against drones is usually an additional element of security, which is among many other team tasks or protection. Therefore, a short training time and simplicity of system use are  important factors when implementing and using the new system.

 

  • Operating conditions of equipment

The basic and obvious operation is to select devices that operate at least under the same conditions in which the drones we want to disarm can operate. 

 

This parameter not only affects the degree of complexity of the application of a solution in the event of a threat, but also for the needs of the user at a time when it is not used, for example in transport.

 

  • The environment in which device will operate

Extremely important information. In most cases, it is the work environment that determines the choice of the right solution. The shape of the protected area and the type of terrain obstacle can effectively exclude certain solutions. 

 

The key feature is the lack of influence of the operating device on human health and communication with the use of mobile phones.


Most often presented methods of countermeasures.

In the beginning, it should be noted that many of the world-proven ways of fighting drones are in fact a training ground for their constructors.

 

The test of the actual suitability of the equipment should be a test carried out by the user himself. It should reflect real conditions and simulate real drones.

 

Much of the solutions below are military in nature. This introduces significant restrictions on the possibility of acquiring a technology and its use in public.

 

 

  • Laser

The development of laser weapons has a longer history than the construction and use of civilian drones. These are powerful systems and dimensions capable of destroying far-reaching targets.

 

Identifying a new threat in the form of commercial drones which can transport explosive or chemical cargo resulted in the production of systems for the destruction of small flying objects. Smaller versions of the HEL MD (High Energy Laser Mobile Demonstrator) have been built and tested. 

 

Progress and miniaturization has led to the creation of the LWS system, which weighs only 300kg and can be prepared for operation in 15 min.

 

When the target is within visual range of the optical system, it takes over the tracking and targeting of the laser beam from the operator.


Zaczęto budować i testować mniejsze wersje rozwiązania HEL MD

 

In the case of low power laser guns, the American solutions of Boeing and German companies Rheinmetall are most well-known.

 

Today's systems are tested with a power of 1-2kW typical for fighting small drones. The principle of operation is the same: detecting the target, heating the element with a laser beam to light

 

Characteristics of solutions

Highly advanced technique comes straight from the methods of combating larger objects than commercial drones. Due to its military importance, this solution is not available to consumers other than the armies of the countries in which these devices are manufactured.

 

 

  • Anti-drone ammunition

The best known solution of this type is EAPS ID (Extended Area Protection and Survivability Integrated Demonstrator). Detecting the drone causes the projectile to fire, which is targeted at the drone.

 

Characteristics of solutions

Military-only technology invented and serves a wider purpose than just destroying small drones. It is still a problem how to detect such small object as a drone. Let alone the problems of using this method in civil areas for example during mass events.

 

 

  • Capturing the drones in the air by another flying object

The idea is based on the use of specially constructed drones to fight other drones.

 

Proper operation and effectiveness of the system will depend on getting really close to the intruder. The minimum distance between them determines the type of solution used (net, thrown ribbon in the propeller, firing plastic balls).

 

The best known and widely displayed solution comes from the French company M.A.L.O.U. After the alarm is generated, the drone is supposed to launch, intercept or catch the intruder, bringing it to the ground or damage it.

 

Przechwycenie lub strącenie drona przez inną maszynę latającą

 

Another solution is the Californian designed and tested method of releasing ribbons into the propeller of an intruder, causing it to fall.

 

Przechwytywanie dronów Rapere

 

There are also individually tested constructions in which devices causing physical damage to the intruder are attached to the drone eg. airsoft paintball rifles.

 

Test drona wyposażonego w pistolet pneumatyczny [VIDEO] 

 

Characteristics of solutions

The common element of all constructions are the interesting ideas and ambitious tasks of intercepting the intruding drone. These solutions are based on combating attackers with specified performance and volatility.

 

In previous films, there is no real tracking simulation and droning with parameters far beyond capture drone capacity, for example:

 

Test quadrocoptera Cobra 2208 [VIDEO]

 

 

  • Shot down with a firearm

The most commonly used weapon is a shotgun. In most cases, before the drones were shot down, they were either hovering or moving relatively slow. 

 

The army has better results with sniper rifles and skilled sharpshooters.

 

(od 4:09) Pokaz możliwości drona o bardzo mocnej konstrukcji

 

Characteristics of solutions

The basic condition is to determine the position of the drone in the sky. The most common problems are caused by white drones on the background of clouds and dark ones on the background of the forest. Even being only 200 meters away from the observer.

 

The second problem is often the speed and manner of moving the drone.

 

There are still legal issues. A wave of drones flooding the US market coincided with the occurrence of shooting incidents, which have already caused a number of lawsuits, such as endangering lives or destroying someone else's property.

 

 

Aresztowanie mężczyzny po zestrzeleniu przez niego drona sąsiadów

 

 

  • Radio jamming

High-power signals in the control band are noises that "cover" the proper signals. A detailed way of realizing this prevention method is the individual approach of the company.

 

Effects can be different, including: the return of the drone to the starting place, the immediate start of the landing process, the breaking of the drone.

 

Characteristics of solutions

Specific external actions cause reactions from drones programmed by their manufacturer or other malfunctions

 

Precise actions in the form of interfering with specific channels that enable the drone to communicate with the environment prove the technical advancement of the given solution.

 

 

 

 

The information presented is based on:
  • The analysis of available solutions (in the form of technical information as well as test solutions);
  • Information about events that have taken place all over the world;
  • Conducted both theoretical and practical studies on the products currently offered;