RU2817392C1 - Method for testing electronic countermeasures systems of unmanned aerial vehicles - Google Patents

Abstract

FIELD: electronic warfare systems.

SUBSTANCE: method for testing electronic countermeasures systems of unmanned aerial vehicles includes receiving signals of the tested electronic countermeasures system using a wideband receiver installed on the unmanned aerial vehicle, and their subsequent processing, which consists in comparing the signal level of the system under test with the signal level, at which there is no navigation task solution for a specific model of unmanned aerial vehicle. Unmanned aerial vehicle is driven along an agreed route. Control of unmanned aerial vehicle is performed in frequency range allocated in advance frequency range allocated in matched frequency range, in which signals of tested system will not be transmitted.

EFFECT: higher safety of an object with an installed electronic countermeasures system due to provision of the possibility of preliminary evaluation of the efficiency of the electronic countermeasures system and timely taking of corresponding measures.

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Description

The invention relates to electronic warfare systems and can be used in the creation and testing of systems for suppressing unmanned aerial vehicles (UAVs).

It is known that any UAV has a number of features that unmask it, which include radio frequency signatures (URL: https://uav-bpla.com/obnaruzhenie_bpla/; published date: 01/12/2023).

It is known that the defeat of UAVs by anti-aircraft missile systems of the air defense forces (hereinafter referred to as air defense), in most cases, is ineffective and leads to a high consumption of ammunition - an irreplaceable material resource. In this regard, the use of electronic jamming equipment (hereinafter referred to as ESM), the resource of which, in the presence of external power, is practically unlimited, is considered a promising direction in countering UAVs. In this case, REP means can be used in one of several ways or a combination of them:

- suppression or imposition of false operating modes of the command radio control line (CRL) and radio data transmission lines of the UAV;

- suppression or imposition of false operating modes on the UAV navigation channel, based on the reception and processing of signals from one or more satellite radio navigation systems (Makarenko S.I. Analysis of means and methods of countering unmanned aerial vehicles. Part 3. Electronic suppression of navigation and radio communication systems. // Control, communication and security systems. - 2020. - No. 2.

In the context of this application, the signals of the EPR system transmitted by the corresponding equipment to the UAV as part of the intended application of the system will be called noise signals or noise.

The creation of effective electronic electronic equipment systems, like any complex technical system, regardless of how they are planned to be used, is impossible without testing, since only mathematical or physical modeling cannot completely replace the verification of compliance of the developed products with agreed upon requirements.

An important parameter that influences the effectiveness of UAV suppression using EPR systems is the so-called signal-to-noise ratio (hereinafter referred to as SNR).

When creating and testing electronic warfare equipment, it is necessary to ensure such a noise level that makes it impossible for the UAV control system to solve navigation problems and/or control tasks, that is, it will ensure the implementation of the air defense function.

In this context, it can be considered that testing of electronic warfare systems should include determining which UAV models and at what distance from the boundaries of a certain zone (hereinafter referred to as the protected object) may be unable to solve navigation problems and control tasks from an external control panel in conditions of counteraction by systems REP installed at this facility.

There is a known method for simulating an unmanned aerial vehicle for testing the guidance system during flight tests, in which the simulator of an unmanned aerial vehicle is placed on an aircraft carrier, the on-board connector of the simulator of the unmanned aerial vehicle is connected to the equipment of the carrier, power is supplied to the on-board connector of the simulator of the unmanned aerial vehicle, at the moment of start The experiment simulates a launch, simulates the operation and current consumption of an unmanned aerial vehicle, and records the information exchange on an internal storage device (pat. RU 2636430, publ. November 23, 2017. Bulletin No. 33). According to a well-known solution, the flight of the aircraft carrier is carried out along a trajectory close to that specified for an unmanned aerial vehicle with normal operation of the homing system and inertial control system.

The disadvantages of the known solution include the need to use a flight carrier, which creates additional interference for detecting UAVs using infrared, acoustic and radio frequency signatures.

The closest in terms of the set of essential features - the prototype of the claimed invention - is a method for simulating echo signals of a moving target in the detection zone of a tested radar station (radar), including the use of an air target simulator installed on a UAV (pat. RU 2776663, publ. 07/22/2022. Bull. No. 21). According to a well-known solution, an air target simulator receives sounding signals from the radar under test, processes them according to a given algorithm and emits them with a polarization corresponding to the polarization of the echo signal of the simulated target, equipped with a flight navigation system that ensures its flight in the far zone of the antenna of the radar under test with movements during the flight in the azimuth-angle plane, similar to the movements of the simulated target, and in range and speed - with the range and flight speed of the simulated target reduced by K times, where the value of K is selected based on the capabilities of the UAV in height and speed of its flight.

The disadvantages of the known solution include the impossibility of its use for testing electronic transmission systems

The technical problem to be solved by the proposed invention is the creation of a method for testing UAV REP systems that does not create the risk of the UAV falling during testing.

The technical result of the implementation of the proposed invention is to obtain a three-dimensional map of the airspace around an object with an installed electronic control system with selected zones of effectiveness of this electronic control system against UAVs of various models (using different ranges and different signals for control). The technical results of the implementation of the proposed invention also include increasing the safety of an object with an installed electronic control system by providing the possibility of preliminary assessment of the effectiveness of the electronic control system and timely adoption of appropriate measures.

The solution to the stated technical problem is achieved by using, to evaluate the effectiveness of electronic electronic transmission systems, a comparison of the measured value of the noise signal created by the tested electronic electronic transmission system and perceived by the receiver installed on board the UAV, with the magnitude of the noise signal at which for a specific UAV model there is no solution to the navigation problem and/or there is no the possibility of control via a radio channel, and during testing the UAV moves along a pre-agreed route, having control over a pre-agreed secure communication channel (frequency range) and/or the UAV moves according to a pre-defined route (movement can be ensured at certain points can be achieved using a coordinate determination module (for example, GPS) and/or, for example, an inertial navigation system that provides navigation of the aircraft. The communication channel is safe insofar as in this frequency range the tested electronic transmission system will not create noise signals (the so-called “transparency window” when). a section of the range is specially selected to control the UAV and this section is not suppressed by the radio electronic control forces).

The proposed method for testing UAV REP systems can be carried out as follows.

The preparatory stage of testing includes coordination of the flight route and the frequency range over which the UAV will be controlled.

The proposed method may include sequential execution of the following steps.

1. Launch of the UAV.

2. Launching the UAV to the starting point.

3. Turning on the REP system under test.

4. Flight of the UAV along an agreed route with simultaneous reception of a noise signal from the tested electronic control system and registration of the parameters of the noise signal with reference to the receiving point.

5. Landing of the UAV using the aircraft control device upon completion of work (such landing can also be carried out automatically using a coordinate determination module and using an inertial navigation system).

The point conventionally called the initial point above is understood as the point from where, in accordance with the test program, the UAV should begin its movement in the specified operating area of the tested electronic transmission system.

The UAV can be controlled via any agreed channel (frequency range) and/or the UAV can follow a predetermined route.

As a result of recording the parameters of the noise signal during testing, a three-dimensional map of the airspace around an object with an installed electronic control system can be obtained. Identification on the map of zones of effectiveness of the tested electronic control system in relation to UAVs of various models, carried out based on the results of comparison of the measured value of the noise signal with the value of the noise signal, at which for a UAV of a particular model there is no solution to the navigation problem and/or control problem, will allow for a timely assessment of the risks for the object from UAVs of various models when using this electronic radar system and take appropriate measures. This comparison can be performed both during the flight of the UAV (this information can be processed - the comparison is made using an on-board PC or an additional PC installed on the ground), and after completion of the flight, using software and hardware included with the UAV , and located at the ground control point of the UAV.

At the same time, it is obvious that for the most effective testing of radio suppression systems protecting an object, it is necessary for the UAV to fly up to the protected object from different directions, from different heights.

Information about the maximum signal/noise level for various UAV models can be obtained from open sources and/or during testing.

In this case, the effectiveness of control channel suppression can be affected by:

- sensitivity of the receiver on board the UAV;

- communication system used for the control channel;

- band width (the larger the band used, the more difficult it is to jam it)

- transmitter power of the control panel

- distance of the control panel to the UAV

For example, studies have shown that when using a spread spectrum communication system (such as, for example, frequency hopping), to reliably block such a channel, the power required is up to 5 times (or even more) than when not using such a channel.¹. (¹ Www.sccs.intelgr.com/archive/2020-02/05-Makarenko.pdf?ysclid=lmhah2crp3473123457) Researchers also provide figures that when using a receiver with a sensitivity of -165 dBW and a control channel using communication systems with PAN (one of methods of spreading the spectrum) for reliable blocking of the signal it is necessary to exceed the interference above the signal by 40-45 dB². (² www.sccs.intelgr.com/archive/2020-02/05-Makarenko.pdf?ysclid=lmhah2crp3473123457)

In this case, the range of the control panel can be selected based on where exactly the object is located (based on the models of the offender, from what minimum distance from the protected object the attacker can control it).

One example of a method for implementing the invention.

At the object selected for testing, systems for blocking a possible control channel and/or navigation systems are turned on (usually the navigation system is in the range of 1200-1300 MHz; 1500-1600 MHz, the control system of standard UAVs is in the range of 1.2-1.3 MHz, 2. 4-2.5 MHz, 5.7-5.9 MHz ³ ( ³ Www.sccs.intelgr.com/archive/2020-02/05-Makarenko.pdf?ysclid=lmhah2crp3473123457)).

At the same time, to increase the likelihood of effective counteraction to UAVs, it is proposed to select the largest range for counteraction, for example, from 100 MHz to 6000 MHz (after all, non-standard operating ranges may be selected by an attacker to control the UAV).

In this case, for example, based on the threat model, the distance from the attacker’s remote control is chosen to be 3 km, with a remote control power of 8 W.

Based on the signal attenuation (can be calculated using the formula - in electronic form here https://r1ban.ru/calc/loss-calc.htm?ysclid=Lmhav971c15270377) the signal level at a specific location of the object in a specific range is determined. To make a decision about the effectiveness of the systems being tested, as well as, if necessary, recommendations for increasing the noise level in a specific range (for this, the power can be increased, different antennas can be used, for example, with a narrower radiation pattern, an additional radiation source can be added, etc. d.) data is used on the required level of excess of the useful signal at which the UAV control system is considered suppressed (data on the excess of the signal for a specific model, a single signal level). To increase the probability of blocking UAV control, the maximum level of excess in the entire range can be selected; as already mentioned, this level of excess for persistent UAV control systems is about 40-45 dB.

All data on the signal level in a specific place of the object from the control panel (can be calculated based on the point of possible location of the control panel using an on-board and/or ground-based PC), on the level of noise excess over the useful signal sufficient for a specific point, indications of the noise level from ground-based systems ( removed using a UAV) are entered into an onboard and/or ground PC (FPGA can be used).

Next, a comparison and calculation takes place and a conclusion is made about the sufficiency or insufficient effectiveness of ground suppression systems.

As an example, we will give one of the ways to implement this application.

It is specified that the remote control is located 3 km from the facility where the anti-UAV system is deployed, the power of the remote control is 8 W.

From the UAV (at an altitude of 500 m above a specific point of the object), the approximate signal level from ground-based countermeasure systems in the range of 300 is calculated, for example, the level will be 80 dB.

Using a PC, the possible signal level from the remote control is calculated in this range, for example, 30 dB.

According to the given conditions, control of the UAV is considered impossible when exceeding 45 dB (may differ in different ranges, depending on different models). Using a PC, a calculation is made: 80 is greater than 45+30 and a conclusion is drawn about the effectiveness of countermeasures in this range, at a specific point in space. In case of insufficient efficiency, a recommendation is made to increase the noise level on a specific band.

The PC can be located both on board the UAV and on the ground (then data from the UAV can be transmitted online using a modem or already entered into the PC when the UAV lands, for example, using a cord).

When using a modem, you can online adjust the operation of suppression systems on the ground.

For example, a UAV can fly over an object in one direction several times, and adjust the operation of suppression systems on the ground to the required efficiency.

For example, a UAV wireless data transmission module vcan 1401 ⁴ ( ⁴ Ivcan.com) can be used as a modem

This module has the following parameters:

- Weight 60 g

- Range - 30 km - TDD-OFDM transmission protocol.

Claims (1)

A method for testing systems for electronic suppression of unmanned aerial vehicles, including receiving signals from the system under test using equipment installed on an unmanned aerial vehicle, and their subsequent processing, characterized in that the signals from the system under test are received using a broadband receiver; the processing consists of comparing the level of signals from the system being tested systems with a signal level at which there is no possibility of control over a radio channel for an unmanned aerial vehicle of a particular model, and during testing the control of the unmanned aerial vehicle is performed in a frequency range allocated in a pre-agreed frequency interval in which signals from the system under test or the unmanned aerial vehicle will not be sent the device moves according to a predetermined route.