EP4176543A1

EP4176543A1 - Method for remotely interfering with electronic equipment

Info

Publication number: EP4176543A1
Application number: EP21740194.2A
Authority: EP
Inventors: Saulius RUDYS; Paulius RAGULIS; Rimvydas ALEKSIEJUNAS
Original assignee: Vilniaus Universitetas
Current assignee: Vilniaus Universitetas
Priority date: 2020-07-03
Filing date: 2021-06-10
Publication date: 2023-05-10
Also published as: LT6913B; LT2020532A; WO2022003456A1

Abstract

The method of remotely interfering with electronic equipment of a target having electronic equipment, comprising generating of more than one signal, and emitting it through one or more antennas. One or more antennas emit signals of different frequencies that reach the target unchanged and excite non-linear frequency mixing processes in the target electronic components that generate at least one signal whose frequency differs from the frequencies of the signals emitted from one or more antennas and corresponds to the operating frequencies of the target electronic equipment.

Description

METHOD FOR REMOTELY INTERFERING WITH ELECTRONIC EQUIPMENT

Technical field

The invention relates to a method of remote interfering with electronic devices by using electromagnetic waves, and, more particularly, with a method for neutralizing electronic equipment by using remote generation of radio signals and their accurate transmission to the targeted equipment.

Background of the invention

The illegal use of unmanned aerial vehicles (UAVs) is a growing public concern. Perhaps the most notable example is the Gatwick airport incident in 2018. To protect the site from UAVs, electronic UAV neutralization measures are also used among the others. Their operation is based on sending sufficiently powerful radio signals to the UAVs at the frequencies at which the systems using radio communication (navigation, telemetry, control, video transmission, radar) operate in order to interfere with operation of these systems. Because these systems operate over a very wide frequency range, several transmitters and several appropriate antennas are typically used. However, when suppressing UAV communication equipment by multi-frequency and/or broadband signals, there is a risk of affecting other aircrafts entering the signal interference area. This is particularly important for satellite navigation (GNSS) systems, which are also used by civilian passenger aircrafts. The existing interference systems emit GNSS frequencies, and this possibility of not affecting regular aircrafts is ensured only minimally - as far as the capabilities of the directional antennas allow.

Conventional remote communication / control systems for interfering electronic equipment emit signals of the frequencies the same as those to be interfered. In order to interfere with the control / communication signals, each signal of separate frequency requires a separate generator and amplifier, and their operating frequencies must coincide with the frequencies used by the electronic system to be interfered. Such a method is disclosed in U.S. Pat. US10,103,835, which describes a portable device and a method for suppressing control / communication signals of unmanned systems.

U.S. Pat. US10,451 ,388B1 discloses a method of neutralizing aircraft by using high power energy density pulses. This method allows generation of extremely strong electric fields at a certain distance from the signal transmission antenna, reaching the air penetration limit. Such a strong electric field is enough to destroy any electronic hardware. The main disadvantage of this system is that n generators are needed to achieve such fields, which can generate ultra-wideband pulses with a duration not exceeding 1 ns. A very strong and wide signal is also generated, which can also affect the operation of the surrounding electronic devices.

U.S. Pat. US8905176B2 describes a device and a method for remotely stopping vehicles by using a modulated microwave signal. In order to reduce the power of the microwave pulses, the patent proposes the use of a system consisting of a vehicle identification device, a database, a microwave signal modulator, and an amplifier. Once the vehicle type has been identified, the following modulator parameters would be selected from the data in the database: microwave frequency (within the L frequency range 1 .2 to 1.7 GHz), amplitude modulation, pulse duration and repetition rate at which the lowest power of the microwave pulse is sufficient to stop the vehicle. The main disadvantage of this method is that, according to the selected vehicle type, the neutralizing signal is generated in the neutralizing device and can damage not only that specific vehicle but also similar vehicles. A database is also needed to selectively affect certain vehicles.

U.S. Pat. US7865152B2 describes a method and an apparatus for remotely neutralizing electronic devices by using microwave signals. The device consists of two microwave signal generators generating different frequencies. These two different signals are fed to the antenna where they add up to each other: the unmodulated signal of one frequency is combined with the unmodulated signal of the other frequency, thus giving the overall signal amplitude modulation with a suppressed carrier without the use of a mixer or a modulator. The main disadvantage of this method is that the interaction of these two signals results in a modulated, pre-prepared control / communication frequency pulse of the electronic devices at the antenna output, which does not selectively neutralize the target. The invention does not have the above-mentioned drawbacks related to the large width of the neutralization signal beam of the electronic equipment and the non-selective effect on the targets. Short description of the invention

The invention discloses the remote neutralization of electronic devices, in particular aircraft or other vehicle electronic devices, by electromagnetic waves. The method comprises using at least two signal generators and supplying such generated signals to the antenna. The signals are selected according to the principles of generating additional frequencies in nonlinear circuits. Second and higher order nonlinearity can be used. Two or more frequencies can also be used.

Interference signal frequencies are selected to take into account the following criteria:

• Frequencies where emission is unwanted.

• Possibility to implement additional spatial selection using nonlinear effects.

• Frequencies where direct (emitted at frequencies exposed to electronic equipment) interference is desired.

• Frequency bands where direct interference and interference using non-linearity are possible.

• Frequencies or frequency bands where interference is required.

• The higher the nonlinearity is used, the weaker the signal will be generated in the nonlinear elements.

By selecting the frequencies of the emitted signals, we can interfere with the communication equipment without emitting the operating frequencies used by that equipment. This avoids unnecessary interference to other communication / control equipment around the radiation source. The generated signals are of different frequencies and remain such until they reach the target. After reaching the target, signals excite nonlinear frequency mixing processes in semiconductor components of electronic devices characterized by the phenomenon of nonlinearity (when the voltage and current do not vary according to the linear principle of Ohm). Such processes include: harmonic generation, cumulative / differential frequency generation, and so on. Thus, signals of additional frequencies that are different from the frequencies of the original signals are obtained. The signals are generated in the electronic circuit of the device itself, which we aim to influence. Since the generation of additional frequencies is based on the effects of nonlinearity, knowing the operating frequencies of the device, we can select the frequencies of external signals so that the signals generated in nonlinear elements correspond to the operating frequencies of the device. The method also includes emitting spectral interference signals at a narrow angle by emitting at least two frequency bands at high frequencies.

Short description of drawings

The features of the invention which is new and non-obvious are given in the Claims. However, the invention may be best understood from the following detailed description of the invention, in which, without limiting the scope of the invention, exemplary embodiments of the invention are given in conjunction with the accompanying drawings, where:

Fig. 1 shows the generation of additional frequencies in electronic equipment having nonlinear (when the voltage and the current do not vary according to the linear

Ohm's principle) elements (diodes, transistors) when the electronic equipment is exposed to at least two signals of different frequencies. Additional frequencies could be a source of interference to communication, navigation or other electronic equipment. Fig. 2 shows a schematic diagram of the method for interference of an unmanned aerial vehicle communication system with the external electromagnetic radiation of different frequencies.

Fig. 3 is a graph showing the change in the number of frequencies generated due to the nonlinearity effect when the device is irradiated with two and three external radiation frequencies. The amplitudes shown are for illustrative purposes only, the amplitudes actually generated may differ from those shown in the figure.

Fig. 4 shows a specific case of electronic communication (Wi-Fi and telemetry) and GNSS navigation equipment interference, combining direct interference (Wi-Fi equipment interference) and interference by using the second order (0.4 GHz telemetry equipment interference) and the third order (GNSS equipment interference) nonlinearities.

Fig. 5 shows a schematic diagram in which one of the signals generated is a broadband signal and the other is a narrowband signal. Due to the interaction of these two signals, the signal generated in the nonlinear element is also a broadband signal. Fig. 6 shows a schematic diagram of instance when two narrowband signals are generated. Their frequencies are changed synchronously in such a way that the signal of the interference generated in the nonlinear element is a phase-modulation signal and the signal spectrum is of the desired width. The most preferred embodiments of the invention are described below with the reference to the drawings. Each figure shows the same numbering of the same or equivalent item.

Detailed description of the invention

It should be understood that numerous specific details are set out in order to provide a complete and comprehensive description of the embodiment example of the invention. However, the skilled person will understand that the emitted level of details of embodiment examples does not limit the embodiment of the invention, which can be embodied without such specific instructions. Well-known methods, procedures and components have not been described in detail to make sure that embodiment examples are not misleading. Furthermore, this description should not be construed as limiting exemplary embodiments provided, but merely as an implementation thereof.

Although exemplary embodiments of the invention, or aspects thereof, as illustrated and described, include many components that are depicted in a particular common space or location, some components may also be remote. It should also be understood that the examples given are not limited to the components described but also include other elements required for their functioning and interaction with other components, the existence of which is self-explanatory and therefore not detailed.

Labeling of items: ".... number.n" indicates an item from the specified minimum to the maximum.

The method according to the invention is intended to remotely interfere with the operation of electronic equipment in a wide frequency range by emitting relatively narrow-band high frequency signals in a narrow beam. The method involves the use of at least two different frequency signal sources (2.1 , 2.2, ...2.n) of remote signal interference system to generate at least two interference signals (1.1 , 1 .2,...1 .n) of different frequencies f2.i , f2.2,...f2.n. The generated interference signals (1.1 , 1.2, ... 1 .n) are sent to at least one antenna (3.1 , 3.2, ... 3.n), which is preferably directional, for radiating said signals to the target (4). The interference signals (1.1 , 1.2, ... 1.n) reach the target (4) essentially unchanged (except for the reduced amplitude due to the natural propagation losses of electromagnetic waves in space).

By using a single antenna (3.1) to radiate all signals to the target (4), a more compact interference system can be obtained. Using separate antennas (3.1 , 3.2, .. 3.n) for each signal (1.1 , 1.2, ... 1 .n) of different frequencies f2.i, f2.2, ... k.n would make the interference system larger, compared to a single antenna system (3.1), but in a system with more than one antenna (3.1 , 3.2, ... 3.n) isolation between different transmitters (2.1 , 2.2, ... 2.n) is not required. Isolation between two transmitters (2.1 , 2.2) in a single antenna system (3.1 ) can be implemented by using different signal polarizations or by using frequency filters. When three or more different interference signals (1.1 , 1.2, 1.3, ... 1.n) interact with nonlinear elements (5), the number of frequencies fi.i, fi.2...fi.n of the generated signals (6.1 , 6.2, ... 6.n) increase in nonlinear elements (5).

When two or more signals (1.1 , 1 .2, ... 1 .n) of different frequencies f2.i, f2.2,...f2.n reach the target (4), such as an unmanned or manned aircraft, differential / cumulative and combination frequencies fi.i, fi.2...fi.n of the signals (6.1 , 6.2, ... 6.n) are generated in the electronic equipment elements (5) of the target (4) due to the nonlinearity of their volt- ampere characteristic. The irradiated electronic equipment of the target (4) receives a wide range of signals (6.1 , 6.2 ... 6.n), which can cause interference to the communication equipment operating in different frequency bands. By selecting the frequencies f2.i, f2.2,...f2.n of the radiated signals (1.1 , 1.2, ... 1.n), we can disturb the communication / control equipment without emitting the signals (6.1 , 6.2, ... 6.n) with frequencies fi.i, fi .2, _ f 1.n corresponding to the frequencies fi.i, fi.2...fi.n of the communication / operation signals of that equipment. When using higher frequency interference signals (1.1 , 1.2, ... 1.n), the directivity of antennas of the same width (3.1 , 3.2 ... 3.n) will be higher than in the case of lower radiated frequencies. Thus, the target (4) is even better distinguished in space. This further improves the distinguishing of targets in space: other nearby objects remain unaffected by interfering radiation. This is particularly true for GNSS systems, as they are used by many users on the ground and in the air, including regular aircrafts. By using a higher frequency, such as several GHz, we can concentrate the radiation energy into a much narrower beam than by using frequencies of hundreds of MHz (with an antenna of the same size). The use of two or more interference signals (1.1 , 1 .2, ... 1 .n) at frequencies f2.i, f2.2,...f2.n allows more freedom in the selection of frequencies f2.i, f2.2,...f2.n of radiated interference signals (1.1 , 1.2, ... 1.n ), thus avoiding important critical frequencies for which signal interference around the target is undesirable. The interference signals (1.1 , 1.2, ... 1.n) are selected according to the principles of generating additional frequencies fi.i,...fi._n in nonlinear circuits. Second and higher order nonlinearity can be used.

The following criteria must be taken into account when selecting interference signal frequencies:

• Frequencies where emission is unwanted.

• Possibility to implement additional spatial selection by using nonlinear effects.

• Frequencies or frequency bands where interference is required.

Frequency selection method:

In one embodiment of the invention, in order to generate one interference signal (6.1 ) in the electronic components (5) of the communication (control) system of the target (4), where the frequency fi.i corresponds to the operation signal frequency fi.i of the communication / control system, two signals (1.1 , 1.2) of different frequencies f2.i, f2.2 are generated in the first and in the second signal generators (2.1 , 2.2) of remote signal interference system. Such signals (1.1 , 1.2) are sent via the antenna (3.1 ) or antennas (3.1 , 3.2, ... 3.n) to the target (4) and reach the electronic components (5) of its communication / control system in the unchanged spectrum, where due to nonlinear effects of the second and the third order, the second or the third order harmonics are generated, respectively. Knowing the frequency fi.i of the electronic equipment operation signal (6.1 ) to be suppressed, the frequencies f2.i, f2.2 of the signals (1.1 , 1.2) generated by the generators (2.1 , 2.2) are selected. The generation of harmonics in the electronic equipment of the target (4) is described by the following formula (7):

/2.1/2.2 ⁼ TG where m is the order of the harmonics generated. In this case, the frequencies of fe_.y or_2.2will be two or more times lower than f _.i, so better spatial selection will not be achieved. To take advantage of the second-order nonlinearity, we choose the frequencies fi .1 and f2.i so that equation (8) is realized: f. ⁼ I/2.1 ± /2.2 I (8)

The case of the cumulative frequencies f2.i and f2.2 means that both of these frequencies will be lower than fi .1 , so it would not be possible to obtain a narrower beam (better spatial selection) by using a fixed-width antenna. Equation (9) would correspond to the case of better spatial selection: f. ⁼ I/2.2 2.11 (9)

In this case, f2.i and f2.2 may be significantly higher than fi.i. In general, the frequencies f2.2 and f2.i can be very different, but in practice there may be frequencies where extraneous radiation may be particularly undesirable, but due to the ambiguous dependence of fi .1 on f2.i and f2.2, it is possible to avoid radiation at those unwanted frequencies.

In another embodiment of the invention, in order to disturb a communication / control system operating on signals of more than one frequency fi .i ,fi .2...fi .n, one generated interference signal (1 .3) is of the same frequency f2.i as one of the operating frequencies of the communication / control system fi .2, i.e., is a direct interference signal. The frequency f2.2 of the other radiated interference signal (1 .4) differs from the frequency f2.i of the direct interference signal (1 .3) and from any other operating frequency fi .i , fi .2...fi .n of the communication / control system. The frequency f2.2 of the said other radiated interference signal (1.4) is chosen according to the formula (10): fz.2 ⁼ I/2.1 ± A.i I (10)i

The addition or subtraction in the formula is selected taking into account the above criteria - spatial selection and the presence of frequencies where interference is highly undesirable.

In the above case, a situation may arise where direct interference at frequency f2.i is desired over a wide frequency range and the frequency range fi .1 is narrow. If, according to formula (9), the frequency f2.2 is a narrowband (carrier only) signal and f2.i is a broadband signal, then fi.i will be the same broadband as f2.i, which may be undesirable because the interference efficiency will decrease. To solve this problem, direct interference in the wide frequency range can be performed by rapidly changing the frequency of the narrowband signal f2.i in the wide frequency range, thus providing direct interference and simultaneously changing the frequency f2.2 according to formula (10). In this case, the frequency f2.2 will not change, but, depending on the rate of change of frequencies f2.i and f2.2, the spectrum of fi .1 will expand due to the resulting phase modulation. By varying the rate of change of frequencies f2.i and f2.2, the spectrum of fi.i of the desired width can be obtained.

To generate the suppressed frequency using third-order nonlinearity, we can use the following formulas (11 , 12): fl.l — 2/2.1 ^— fz.z_> (11 ) fi.i = 2/2.2 - fz.i, (12)

Using the same principles as in the case of second-order nonlinearity, it is possible to avoid unwanted interference frequencies and at the same time realize direct interference. When f2.2> f2.i, it is better to use formula (11), because in this case fi.i will be smaller than f2.i and f2.2, so it is possible to narrow the beam of the transmitted signal.

Using three different generators and to generate the frequency arising from the second- order nonlinearity, the frequency fi.i generated in the nonlinear elements can be found by equation (13):

Given that there may be situations where three generators are used to interfere with the electronics, then the frequencies fe_.y, fe.2 and fz3 generated by them must satisfy the following condition (14): fi.i = fz.i + fz._j ± fz._k> kai i,j ¹ k, (14) where i; j; k = 1 ; 2; 3 are the frequencies generated by the generators (2.1 , 2.2, ... 2.n), fi .1 is the frequency of the third order nonlinearity due to the three external frequencies. Other Embodiments of the Invention:

The standard way of interfering with and disturbing aircraft electronic equipment, and especially communication equipment, is to send interference on the GNSS and control system frequencies and thus block navigation and control systems of the UAV. Sending interference on GNSS frequencies in the airport area is absolutely unacceptable, as GNSS systems are used by passenger aircrafts. According to embodiment of the invention and as shown in Figure 4, radio signal beams (1.5, 1.6) with frequencies of 2 GHz and 2.4 GHz are directed to the aircraft. The signal (6.3) is formed in the communication electronic components (5) of the target (4), the frequency of which blocks the control or telemetry frequency of 400 MHz of the target (4) (second order nonlinearity 2.4-2 = 0.4 GHz). The 1 .6 GHz frequency GNSS signal (third order nonlinearity 2x2-2.4 = 1 .6 GHz) is also blocked and the control and telemetry range of 2.4 Ghz of the target (4) is directly blocked. Since the GNSS signal is not radiated, this avoids unwanted interference with the GNSS navigation system for passenger aircrafts and surrounding users. Appropriate modulation of the emitted signals should be selected for maximum interference efficiency.

In another embodiment of the invention, the selectable frequencies of the external signals (1.7, 1.8) are I2.3 2.0 GHz and f2.4 = 2.4 GHz. When such signals (1.7, 1.8) affect the nonlinear element (5), it generates additional signals fi .3 = 0.4 GHz (second order nonlinearity) and f 1 .4 = 1 .6 GHz (third order nonlinearity 2x2 GHz-2.4 GHz = 1 .6 GHz) (6.3,

6.4). The 1 .6 GHz frequency is approximately the L1 frequency range for GNSS systems. This is particularly true for GNSS systems, as they are used by many users on the ground and in the air, including regular passenger aircrafts.

When suppressing Wi-Fi and GNSS frequencies, we are facing a problem: the Wi-Fi range is wide - about 100 MHz, and GNSS is narrow - about 1 MHz. Using a broadband (say, 100 MHz bandwidth) 2.4 GHz signal (1.10) and a monochrome 2 GHz signal, the response generated in nonlinear elements will be broadband, reducing GNSS interference efficiency. To solve this problem, a narrowband but variable frequency (varying within 100 MHz) signal should be used for interference in the 2.4 GHz Wi-Fi band. Frequent frequency hopping within 100 MHz range can suppress signals over the entire Wi-Fi range. When the frequency of one of two signals changes, the frequency of the nonlinear response will also change, therefore we must change the frequencies of both signals synchronously, so that we get the required nonlinear response frequency. The required spectrum of GNSS or other interfering signal can be obtained by modulating one of the two frequencies, or/and changing the rate of frequency change (hopping). The higher the hopping speed, the wider the range. In yet another embodiment of the invention, one or more interference signals (1.1 , 1.2, ... 1.n) of different frequencies f2.i , f2.2, ...f2.n are generated not in the remote interference system having one or more signal generators (2.1 , 2.2), but in other devices, such as nearby radio or television broadcasting stations, radars and other strong radio signal sources, having signal generators (2.3, ... 2.n) whose signals are emitted through the antennas (3.3, ... 3.n) and reach the target (4). In this case, by knowing, what frequency f2.i , f 2.2, ... f2.n of signals (1.1 , 1 .2, ... 1 .n) reach the target (4), one or more additional signals with frequencies suitable for the electronic equipment elements (5) of the target (4) would be generated in the remote electronic-equipment interference system by one or more signals generators (2.1 , 2.2), so due to the nonlinearity of the volt-ampere characteristics in the target elements differential / cumulative and combination signals (6.1 , 6.2, ... 6.n) of interference frequencies fi .i , fi .2...fi .n will be generated. The characteristics of the interference signals are calculated in the same way as above, according to formulas (7) to (14).

Although the present description includes numerous characteristics and advantages of the invention together with structural details and features, the description is given as an example of the invention embodiment. There may be changes in the details, especially in the form, size and layout of materials without departing from the principles of the invention, in accordance with the widely understood definition of terms used in claims.

Claims

1 . The method of remotely interfering with electronic equipment of a target (4) having electronic equipment, comprising generating and emitting more than one signal (1.1 , 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 1.10 ... 1.n) through one or more antennas (3.1 , 3.

2, ...

3.n), characterized in that one or more antennas (3.1 , 3.2, 3.3 ... 3.n) emit signals (1.1 , 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 1.10 ... 1.N) of different frequencies f2.i,f2.2, k.3, h.A..h.n that reach the target (4) unchanged and excite non-linear frequency mixing processes in the electronic components (5) of the target (4), which generate at least one signal (6.1 , 6.2, 6.3, 6.4, ... 6.n) having a frequency fi i ,fi .2, fi .3, fi A fi n that differs from the frequencies f2.i,f2.2, f2.3, f2.4,...f2.n of signals (1.1 , 1 .2, 1 .3, 1 .4, 1 .5, 1 .6, 1 .7, 1 .8, 1 .9, 1 .10 ...1 .n) emitted from one or more antennas and corresponds to the operating frequencies fi .1 ,fi .2, fi .3, fi .4,...fi .n of electronic equipment of the target (4). 2. The method according to claim 1 , wherein the electronic components (5) of the target

(4) are excited by the harmonic according to the formula (7): f .1/2.2 ⁼ TG where m is the sequence of the generated harmonics, fi.i is the frequency of the signal (6.1) generated in the target electronic components (5), f2.i and f2.2 are the frequencies generated by the first and the second external generators (2.1 , 2.2, 2.3).

3. The method according to claim 2, wherein the damping frequency fi.i is generated by using a second order nonlinearity. 4. The method according to claim 3, wherein the signals (1.1 , 1.2) emitted at different frequencies f2.i, f2.2 comprise frequencies f2.i, f2.2 satisfying the following equation (8): f. ⁼ I/2.1 ± /2.2 I (8) where fi.i is the frequency of the signal (6.1) generated in the target electronic components (5), f2.i and f2.2 are the frequencies generated by the first and the second external generators (2.1 , 2.2, 2.3).

5. The method according to claim 3, wherein the signals (1.1 , 1.2) emitted at different frequencies f2.i, f2.2 comprise frequencies f2, f3 satisfying the following equation (9): f . ⁼ I/2.1 ^— /2.2 I (9) where fi.i is the frequency of the signal (6.1) generated in the target electronic components (5), f2.i and f2.2 are the frequencies generated by the first and the second external generators (2.1 , 2.2, 2.3).

6. The method according to claim 3, wherein the frequency fi.i generated in the electronic components (5) of the target (4) can be found according to the following equation (13): f_{X i} = \f₂.i ± f_2.j\, kai i ¹j (13) where /, j = 1 , 2, fi.i is the frequency of the signal (6.1) generated in the target electronic components (5), f2.i, and f2.2 are the frequencies generated by the first and the second external generators (2.1 , 2.2, 2.3). 7. The method according to any one of claims 1 to 5, wherein one or more of the frequencies f2.i ,f2.2, f2.3, f2.4,...f2.n of the emitted signals (1.1 , 1.2, 1 .3, 1 .4, 1 .5, 1 .6, 1 .7, 1 .8, 1 .9, 1.10 ... 1 .n) is the same as the operating frequency fi.i of electronic equipment of the target (4), and two or more of frequencies f2.i ,f2.2, f2.3, f2.4,...f2.n of the emitted signals (1 .1 , 1 .2, 1 .3, 1 .4 , 1 .5, 1 .6, 1 .

7, 1 .8, 1 .9, 1.10 ... 1 .n) differ from operating frequency fi .1 ,fi .2, fi .3, fi .4,...fi .n of electronic equipment of the target (4).

8. The method according to claim 7, wherein one of the radiated frequencies f2.i is a direct interference frequency and the other radiated frequency f2.2 has values according to the following formula (10): /₂.2 = l/2.i ± /i.il (10) where f2.2 is the frequency of the signal (6.1 ) generated by the target electronic components (5), f2.i is the direct interference frequency generated by the first external generator (2.1 ), fi .1 is the interference frequency generated by the target electronic components (5).

9. The method according to claim 2, wherein the damping frequency fi .1 is generated using third order nonlinearity.

10. The method according to claim 9, wherein the signals (1.1 , 1.2) emitted at different frequencies f2.i, f2.2 comprise frequencies f2.i, f2.2 satisfying the following equation (11): fl.l ⁼ 2/2.1 ^— fz (^ 1 ) where fi.i is the frequency of the signal (6.1) generated in the target electronic components (5), f2.i and f2.2 are the frequencies generated by the first and the second external generators (2.1 , 2.2, 2.3).

11. The method according to claim 9, wherein the signals (1.1 , 1.2) emitted at different frequencies f2.i, f2.2 comprise frequencies f2.i, f2.2 satisfying the following equation (11): fi.i ⁼ 2 2.2 ^— /2.1 (^ 1 ) where fi.i is the frequency of the signal (6.1) generated in the target electronic components (5), f2.i and f3.2 are the frequencies generated by the first and the second external generators (2.1 , 2.2, 2.3).

12. The method according to claim 9, wherein the frequency fi .1 generated in the electronic components (5) of the target (4) can be found according to the following equation (14): f_l.l = fz.i + fz._j ± f_2.k> kai i,j ¹ k, (14) where i; j; k = 1 ; 2; 3 are the frequencies generated by the generators (2.1 , 2.2, 2.3), fi .1 is the frequency of the third order nonlinearity due to the three external frequencies.

13. The method according to any of the preceding claims, wherein the signal spectrum of the generated signal in the nonlinear elements is obtained due to the phase modulation occurring synchronously by varying the frequencies of the radiated signals at a certain rate.

14. The method according to any of the preceding claims, wherein the signal spectrum of the signal generated in the nonlinear elements is obtained due to modulation of signals at frequencies f2.i , f2.2, f2.3, f2.4,...f2.n generated by the generators (2.1 , 2.2, ...2.n).