KR20220122021A - Radio frequency jamming device for preventing unmanned aerial vehicle approach - Google Patents

Abstract

Disclosed is a communication blocking device of a jamming signal transmission type. According to an embodiment of the present invention, a communication blocking device of a jamming signal transmission type comprises: a signal generation unit for generating white noise having an intermediate frequency band; a controller unit for determining a target frequency band; an up-conversion unit for up-converting the white noise having the intermediate frequency band to the target frequency band received from the controller unit and outputting a signal; an amplifier unit for amplifying the signal output from the up-conversion unit; a transmission unit for transmitting the signal amplified by the amplifier unit to the air; and a power supply unit for supplying operating power to the signal generation unit, the controller unit, the up-conversion unit, and the amplifier unit. The communication blocking device of a jamming signal transmission type, for preventing approach of an unmanned aerial vehicle can respond to various radio frequency ranges while having mobility and portability.

Description

Radio frequency jamming device for preventing unmanned aerial vehicle approach

The present invention relates to blocking and protection of wireless communication, and more particularly, to a portable radio wave jamming device capable of coping with the intrusion of an unmanned aerial vehicle such as a drone penetrating into the air while being portable and movable.

Unmanned aerial vehicles (UAVs) have been used for military purposes in the early days, but with the recent development of manufacturing technology, miniaturization, weight reduction, and low cost of unmanned aerial vehicles have been achieved, and they have been greatly expanded for private business and hobby purposes. In particular, a copter-type drone that is controlled by connecting it to a smartphone or a dedicated controller is only about 20 cm in length and has a price of several hundred thousand won.

However, due to the civilian supply of unmanned aerial vehicles, in areas where flying is prohibited or in areas where entry/photography is prohibited, such as civil/military aviation facilities, national major facilities such as power plants, military bases, etc. Flying and filming drones, the threat of security breaches and the risk of human life/facility accidents are increasing day by day.

In fact, Incheon Airport, which has a radius of 9.3 km designated as drone-flying airspace, was sent to Incheon Airport control, where a young man who did not familiarize himself with the relevant laws was flying a drone near Gimpo Airport to film material to be submitted to a video contest. As a state of emergency was declared, five passengers made a return landing at Gimpo Airport.

To prepare for this, each facility where drone flight is prohibited is equipped with a capture net gun, or a cooperative system to crack down on unauthorized drone operators such as the local army/police is established. We are preparing for it.

However, the effective distance of the capture net gun is short, less than 15 meters, and it is difficult to aim, and the system that cracks down on the operator is a post-sanction method, so the effectiveness is being questioned. Due to the high risk of collateral damage to human life and facilities caused by heavy Korean grenades and robbery, it is considered a low practical method.

Currently, the wireless communication disruption method is the most popular as a method of refusing drones because the possibility of collateral damage is the lowest and it can fundamentally block the access of drones.

The wireless communication network used for drones, etc. transmits radio waves in the air so that information can be exchanged in various forms such as one-to-one, many-to-one, and one-to-many. It is called radio communication disturbance (jamming).

The principle of the wireless communication disturbance method is to interfere with normal radio reception by lowering the signal-to-noise ratio of the receiver by emitting a high-intensity jammer of the same frequency as the radio wave received by the receiver. For example, Korean Patent Registration No. 1999-0083728 discloses a radio jammer of the prior art. However, the conventional jammer transmitter for wireless communication disturbance operates in a fixed frequency band, and since the antenna is fixed to the ground or equipment, it is bulky and difficult to move, so it is difficult to apply it to an unmanned aerial vehicle that can penetrate the air. have.

Accordingly, the present invention has been devised to solve the above problems, and it is to provide a jamming wave transmission type communication blocking device for preventing unmanned aerial vehicle access, which can respond to various radio frequency ranges while having mobility and portability.

Other objects of the present invention will become clearer through preferred embodiments described below.

According to an aspect of the present invention, there is provided a signal generator for generating white noise in an intermediate frequency band; a controller unit for determining a target frequency band; an up-converter for up-converting the white noise of the intermediate frequency band into the target frequency band received from the controller and outputting a signal; an amplifying unit amplifying the signal output from the up-converting unit; a transmitter for transmitting the signal amplified by the amplifying unit to the air; a power supply unit for supplying operating power to the signal generating unit, the controller unit, the up-converting unit, and the amplifying unit; includes

Here, the controller unit may preset the target frequency band to GPS (1160 MHz to 1790 MHz), ISM 2.4 (2400 MHz to 2483.5 MHz), and ISM 5.8 (5725 MHz to 5825 MHz).

Here, the controller unit may further include at least one selection means, and the target frequency band may be selected by the selection means.

Here, the jamming radio transmission type communication blocking device further includes a handle portion and a trigger portion, wherein the trigger portion is arranged so that the user's hand can operate the trigger portion while holding the handle portion, the trigger portion An amplification gain (Gain) of the signal amplified by the amplifying unit may be adjusted by the operation of .

Here, the amplification unit includes at least two amplification modules that can be connected in parallel to each other, and the number of amplification modules connected in parallel to each other can be adjusted by the operation of the trigger unit.

Here, the power supply unit further includes a battery, and the battery may be charged with 220V AC single-phase power connected from the outside.

Here, the transmitter may include a broadband antenna having an emission beam width of 20 degrees or less.

Here, the jamming wave transmission type communication blocking device may further include a filter unit for suppressing signals other than the target frequency band among the signals output from the amplification unit and outputting the signals to the transmitting unit.

Here, the jamming wave transmission type communication blocking device may further include a shield-shaped external case.

According to another aspect of the present invention, there is provided a method for blocking communication by a jamming wave transmission type communication blocking device, the method comprising: determining a target frequency band; generating white noise in an intermediate frequency band; outputting a signal by up-converting the white noise of the intermediate frequency band into the target frequency band; amplifying the signal; transmitting the amplified signal to the atmosphere; It may be a communication blocking method comprising a.

According to the present invention, it is possible to provide a jamming wave transmission type communication blocking device for preventing an unmanned aerial vehicle approaching that can respond to various radio frequency ranges while having mobility and portability.

1 is a block diagram according to an embodiment of the present invention.
2 is a block diagram of an amplifier according to an embodiment of the present invention.
3 is an external functional block diagram of a shield-type communication blocking device according to an embodiment of the present invention.
4 is an external perspective view of a shield-type communication blocking device according to an embodiment of the present invention.
5 is a flowchart of a communication blocking method according to an embodiment of the present invention.

Since the present invention can apply various transformations and can have various embodiments, specific embodiments are illustrated in the drawings and described in detail in the detailed description. However, this is not intended to limit the present invention to specific embodiments, and should be understood to include all modifications, equivalents, and substitutes included in the spirit and scope of the present invention. In describing the present invention, if it is determined that a detailed description of a related known technology may obscure the gist of the present invention, the detailed description thereof will be omitted.

Terms such as first, second, etc. may be used to describe various elements, but the elements should not be limited by the terms. The above terms are used only for the purpose of distinguishing one component from another.

The terms used in the present application are only used to describe specific embodiments, and are not intended to limit the present invention. The singular expression includes the plural expression unless the context clearly dictates otherwise. In the present application, terms such as “comprise” or “have” are intended to designate that a feature, number, step, operation, component, part, or combination thereof described in the specification exists, but one or more other features It is to be understood that this does not preclude the possibility of the presence or addition of numbers, steps, operations, components, parts, or combinations thereof. Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a block diagram according to an embodiment of the present invention. In the present invention, the intermediate frequency white noise generated by the signal generator 110 is up-converted into a signal of the target frequency band through the up-converter 120 , and then amplified by the amplifier 130 and then the transmitter 140 . It may be a jamming wave transmission type communication blocking device that is transmitted to the air through the

The signal generator may generate white noise of an intermediate frequency (IF) band. The intermediate frequency may be a frequency of 100 to 500 MHz. The intermediate frequency may mean a frequency between a radio frequency (RF) and a baseband frequency. As for the intermediate frequency, 10.7 MHz in FM radio and 45.75 MHz in analog television can be used. The purpose of using the intermediate frequency in wireless communication may be to not generate a resonance signal in an unwanted frequency band. In addition, the cost may be reduced by using a filter for suppressing unwanted frequency band signals at a lower cost. Furthermore, it may be because there is no suitable electronic device capable of directly and stably generating a high-frequency signal of 1000 MHz or more, or it is difficult to realize characteristics.

In the signal generator, two or more signals may be swept in an intermediate frequency band. In this case, one or more Direct Digital Synthesizer (DDS) or Field Programmable Gate Array (FPGA) may be selected and combined to generate two or more signals.

The signal generator may be configured as an individual signal generator to generate signals independent of each other for each channel. Each signal generator may generate a separate intermediate frequency white noise. In some cases, it may be composed of individual signal generators corresponding to the number of channels.

The controller unit may transmit a target frequency band, which is a frequency band desired for disturbance, to the upconverter. In this case, the power required for the operation of the controller unit may be supplied from the power supply unit.

According to another embodiment of the present invention, the target frequency band of the controller unit may be preset to GPS (1160 MHz to 1790 MHz), ISM 2.4 (2400 MHz to 2483.5 MHz), and ISM 5.8 (5725 MHz to 5825 MHz). When the target frequency band is set to the three frequencies as described above, the white noise may be upconverted into the three frequency bands by the upconverter.

According to another embodiment of the present invention, the target frequency band of the controller unit may be selected by the selection means.

The target frequency band may be a radio frequency required for a disturbance target (eg, a drone for photographing) to operate. For example, it may be a frequency at which a GPS signal is used.

Drones are equipped with positioning systems such as INS (Inertial Navigation System) and GPS (Satellite Navigation System) to determine their location. Among them, GPS is a system that receives radio waves from location information satellites around the earth, and can determine the current latitude and longitude and altitude with an error of several meters through the time difference of the received radio waves.

Alternatively, the radio frequency required for the operation of the drone may be the ISM 2.4 (2400 MHz ~ 2483.5 MHz) band or the ISM 5.8 (5725 MHz ~ 5825 MHz) band. The ISM band may be an industrial, scientific, or medical frequency band designated by the International Telecommunication Union. ISM 2.4 band and ISM 5.8 band may be representative wireless Internet bands, and may be frequency bands used to control drones wirelessly.

Therefore, in order to neutralize the drone, the GPS (1160 MHz ~ 1790 MHz), ISM 2.4 (2400 MHz ~ 2483.5 MHz), and ISM 5.8 (5725 MHz ~ 5825 MHz) bands may be the target frequency bands, preferably GPS L1 (1575.42 MHz), GLONASS Band A (1560 to 1605 MHz) including L1 (1601.156 MHz) and BeiDou B1 (1561.098 MHz) bands, GPS L2 (1227.6 MHz), GPS L5 (1786.45 MHz), GLONASS L2 (1245.34 MHz), GLONASS L3 (1201.7) MHz), BeiDou B2 (1207.14 MHz), and BeiDou B3 (1268.62 MHz) band B band (1160 to 1280 MHz) may be a target frequency band.

According to another embodiment of the present invention, the target frequency band is LRS RF (433 MHz), GSM (850 MHz ~ 900 MHz), WCDMA (1800 MHz ~ 2100 MHz) for disturbance of ISM 2.4, ISM 5.8, and unmanned aerial vehicles that do not use GPS. , LTE (1800 MHz to 2100 MHz), NR 5G (3.5 GHz and/or 28 GHz). LRS RF is spotlighted overseas as a frequency band for use in civilian hobby and military domains. It is known that the long communication distance (more than 11km) due to the low frequency is an advantage.

However, 1030MHz and 1090MHz may be used for transmission and response of Squawk code of MODE A, a civil aviation track identification protocol. If 1030 MHz and 1090 MHz are target frequency bands, there is a possibility of threatening the safety of civil aircraft. caution may be required. For example, appropriate azimuth, elevation restrictions or power restrictions may apply.

In addition to the above frequency bands, any frequency may be selected as the target frequency band as long as it is a frequency for remote control and image transmission of civilian and military unmanned aerial vehicles.

According to another embodiment of the present invention, the selection means for allowing the target frequency band to be selected may be a button. More specifically, the selection means may be composed of a button for increasing the frequency and a button for decreasing the frequency.

When the selection means is a button, it may further include a display to represent the currently selected frequency. The display may be a calculator-type liquid crystal numeric display with four digits. Preferably, it may include a backlight for night operation. More preferably, it may include a red backlight for night operation. Since red has the least ability to impede the eye's dark adaptation, it may be suitable for operators to ensure a suitable environment for visual identification of drones at night.

According to another embodiment of the present invention, the selection means for allowing the target frequency band to be selected may be a dial. The dial may be a continuous dial without stops. The selectable target frequency band range of the dial may be from 0.4 GHz to 11 GHz. Preferably, it may be 1160 MHz ~ 5825 MHz. According to another embodiment, the dial may be a discontinuous dial with stops. The discontinuous dial selection value may be three of GPS, ISM 2.4, and ISM 5.8.

According to another embodiment of the present invention, the selection means may be in the form of an exchangeable card, pack or chip. If the selection means is implemented in the form of an exchangeable card, pack, or chip, and a target frequency suitable for the inserted card, pack, or chip is selected only when the card, pack, or chip is inserted, then there are many information and communication devices. As it is being utilized, there may be an advantage of minimizing collateral damage and unintended use in an area where collateral damage is expected due to the use of the present invention jammer transmission type communication blocking device. For example, in a facility where the ISM 2.4 band is actively used for reasons such as the establishment of an IoT sensor network, if only the GPS chip is used as a means of selection and the ISM 2.4 chip is stored so that only high-ranking security personnel can disburse it, collateral damage may occur. can be prevented.

The up-converter may up-convert the white noise of the intermediate frequency band to the target frequency band received from the controller. The power required for the operation of the upconverter may be covered by DC power supplied from the power supply.

The up-converter functions to convert the white noise of the intermediate frequency band generated by the signal generator into the target frequency band, and for this, a plurality of BPFs, IF mixers and RF mixers may be provided.

The up-converter may have a frequency conversion function using a wideband mixer, an output control function for a short-range target, and an interference minimization function using a filter.

2 shows an amplifying unit according to an embodiment of the present invention.

The amplifier 130 includes an input-side coupler 131, an input detection unit 136, a driving amplifier 132, a main amplifier 133, an output-side coupler 134, an output detection unit 137, a circulator 135, A reflected signal detection unit 138 may be included.

The input detection unit may detect input power from an input-side coupler disposed at a front end of the driving amplifier. The output detection unit may detect output power from the output-side coupler. The reflected signal detector may detect a reflected signal from the circulator.

The amplifying unit may amplify a signal output from the upconverting unit. Power required for the operation of the amplifying unit may be supplied as 24V DC power from the power supply unit. The signal output from the amplification unit may have a power level 18 dB higher than the original signal reception level of the blocking object.

According to another embodiment of the present invention, the amplification unit may include at least one or more amplification modules 139 connected in parallel. Since the amplification modules are connected in parallel, there is an advantage that the amplification gain can be easily adjusted by controlling whether each of the amplification modules operates. In addition, it is possible to minimize the output degradation even when the amplification module fails.

The transmitter may perform a function of transmitting the amplified signal to the air. The amplified signal may contain disturbing propagation. The target frequency band may be variously set by the controller.

When the transmitter emits a jamming wave to disable an unmanned aerial vehicle such as a drone, it can transmit the jamming wave in a distributed spectrum method to disable the remote control transmitter/receiver module of the unmanned aerial vehicle. Alternatively, the frequency hopping type jamming wave may be transmitted to confuse the remote controller transceiver module of the unmanned aerial vehicle, or to induce disconnection between the unmanned aerial vehicle remote controller transceiver module and the unmanned aerial vehicle remote controller. When the disturbance of the unmanned aerial vehicle is successful by the jamming radio transmission type communication blocking device according to the present invention, the unmanned aerial vehicle is forced to return home (return to the first take-off location and land) by the Fail-Safe system, maintain hovering, or You can land on the ground at any location.

According to another embodiment of the present invention, the transmitter may further include a directional broadband antenna having an emitted beam width within 20 degrees. For example, when the remote controller of an unmanned aerial vehicle is 1 km away and its output is 1 W, and the transmitter according to an embodiment of the present invention has an output of 2 W, in the case of an omni-directional 5 dBi antenna, effective disturbance is possible only within 200 m. However, in a directional antenna with a beam width of less than 20 degrees, the effective disturbance distance is doubled to 400 m. In addition, since the jamming wave is transmitted only in the direction directed by the transmitter, there is an additional effect of preventing communication failure for personnel and facilities in an unwanted direction.

The power supply unit may supply power to the signal generating unit, the up-converting unit, the amplifying unit, and the controller unit. The type of power supplied by the power supply unit is preferably 24V DC.

According to an embodiment of the present invention, the power supply unit may further include a battery capable of supplying 24V power. The form of power supplied by the power supply unit may be 24V DC directly connected to the battery and received.

According to another embodiment of the present invention, the power supply unit may further include a DC converter for converting 220V AC single-phase power to 24V DC power. The power supplied by the power supply unit may be 220V AC single-phase power commonly used for home and office use, and the supplied power may be 24V DC converted by a DC converter.

The power supply unit according to another embodiment of the present invention may further include a power input unit. The power input port may be an input unit of an 8-character code. Alternatively, the power input unit may be a connection unit of a DC power adapter. Alternatively, it may be a USB cable.

According to another embodiment of the present invention, the present invention jamming radio transmission type communication blocking device is a filter 145 for outputting a signal output from the amplifying unit to the transmitting unit in order to suppress signals other than the target frequency band among the signals output from the amplifying unit. ) may be further included.

3 is an external functional block diagram of a shield-type communication blocking device according to an embodiment of the present invention. In the drawing, a shield-type external case 190 , a handle unit 180 , and a power input unit 151 are implemented.

According to another embodiment of the present invention, the present invention may further include a handle portion and a trigger portion. An example of the handle is shown in FIG. 3 . When the operator grabs the handle, the handle may be formed so that the transmitter may face the object of disturbance. Although not shown in FIG. 3, the trigger part may be formed adjacent to the handle part. It is preferable that the trigger unit is pressed by the manipulation of the operator's index finger or thumb. The amplification gain of the signal amplified by the amplifying unit may be adjusted by the operator's operation of the trigger unit.

According to another embodiment of the present invention, the method of adjusting the amplification gain may be a method in which the number of amplification modules connected in parallel to each other is adjusted. For example, the trigger can be activated by dividing the operator's pressing force into three levels. If the operator presses the trigger as one of three levels, only one amplifier can be connected. If the operator presses the trigger force is 3 out of 3 stages, three amplification units may be connected.

According to another embodiment of the present invention, the transmitter may include a super-directional beamforming antenna having an azimuth angle of 5 degrees or less. Here, a sighting device may be further included so that the operator can accurately aim the unmanned aerial vehicle. Aiming devices can be sights and scales. After the operator aligns the sight and the scale on the line of sight, the operator can aim the obstructive object at the sight to aim accurately.

According to another embodiment of the present invention, the present invention may further include a standard picatinny rail for mounting the sighting device. The sighting device may be a magnification sight, a red dot sight, or a night sight. The Picatinny rail is a standard accessory system currently in use by the military so that optical sights, handles, and lighting devices can be easily attached and removed. High-performance optics such as magnification sights and red dot sights used for military use by the Picatinny Rail can be easily attached and removed. For example, the PVS-04K is a monocular night sight, which has a night vision function and a variable control function of 1 to 3 magnifications. The intrusion of an unmanned aerial vehicle at night time is difficult to identify with the naked eye, but the effect of the present invention can be further increased by combining it with a monocular night sight.

Figure 4 is an external perspective view of the shield-shaped communication blocking device according to an embodiment of the present invention is shown. According to another embodiment of the present invention, the present invention may further include a shield-shaped exterior case (190). The shield shape has the advantage of easy storage due to its relatively thin shape. In addition, for personnel on standby in preparation for infiltration of unmanned aerial vehicles, who store equipment such as vests on the wall, the shield shape may be easy to hang like a vest. Therefore, the shield-type shape may provide an operator with an advantage of convenient use.

5 is a flowchart of a communication blocking method according to an embodiment of the present invention. According to an embodiment of the present invention, the present invention comprises the steps of determining a target frequency band; generating white noise in an intermediate frequency band; outputting a signal by up-converting the white noise of the intermediate frequency band into the target frequency band; amplifying the signal; transmitting the amplified signal to the atmosphere; may include.

In the step of determining the target frequency band, a target frequency band that is a frequency band to be disturbed is determined. The target frequency band may be determined by the radio communication protocol frequency being used by the target unmanned aerial vehicle.

According to another embodiment of the present invention, in the step of determining the target frequency band, the operator may input the target frequency band. A target frequency band may be input by the button. The target frequency band input by the button may be displayed on the liquid crystal display screen.

According to another embodiment of the present invention, a target frequency band may be input by a dial.

In the step of generating the white noise of the intermediate frequency band, the white noise may be generated in the range of 100 to 400 MHz.

In the step of outputting a signal by up-converting the white noise of the intermediate frequency band to the target frequency band, the white noise may be up-converted into a signal of the determined target frequency band. For example, when the target frequency band is the ISM 2.4 band, the white noise of the intermediate frequency band may be up-converted into a signal suitable for the ISM 2.4 band.

In the step of amplifying the signal, the upconverted signal may be amplified.

According to another embodiment of the present invention, the step of amplifying the signal may be performed by the amplifying unit. The amplification gain of the signal amplified by the amplification unit may be adjusted by manipulation of the trigger unit. If the trigger is pressed strongly, the amplification gain may become a large value, and if the trigger is pressed lightly, the amplification gain may become a small value.

According to another embodiment of the present invention, the step of amplifying the signal may be performed by at least one amplifying module included in the amplifying unit. In addition, the communication blocking method of the present invention may further include the step of adjusting the number of amplification modules connected in parallel to each other by the operation of the trigger unit. For example, three amplification modules can be connected in parallel to obtain a high amplification gain by pressing the trigger part strongly. For another example, only one amplification module can be connected to obtain a low amplification gain by pressing the trigger part lightly.

The above-described preferred embodiments of the present invention have been disclosed for the purpose of illustration, and various modifications, changes, and additions may be made by those skilled in the art with respect to the present invention within the spirit and scope of the present invention, and such modifications, changes and Additions should be considered to fall within the scope of the following claims.

100: present invention jamming wave transmission type communication blocking device
110: signal generator
120: up-converter
130: amplification unit
140: transmitter
150: power supply
160: controller unit
139: amplification module
180: handle part
190: shield shape outer case
151: power input unit
S200: Communication blocking method by the present invention jamming wave transmission type communication blocking device

Claims (10)

a signal generator generating white noise in an intermediate frequency band;
a controller unit for determining a target frequency band;
an up-converter for up-converting the white noise of the intermediate frequency band into the target frequency band received from the controller and outputting a signal;
an amplifying unit amplifying the signal output from the up-converting unit;
a transmitter for transmitting the signal amplified by the amplifying unit to the air;
a power supply unit for supplying operating power to the signal generating unit, the controller unit, the up-converting unit, and the amplifying unit;
A jamming wave transmission type communication blocking device comprising a.
According to claim 1,
The controller unit is a jammer transmission type communication blocking device, characterized in that the target frequency band is preset to GPS (1160 MHz ~ 1790 MHz), ISM 2.4 (2400 MHz ~ 2483.5 MHz), ISM 5.8 (5725 MHz ~ 5825 MHz).
According to claim 1,
The controller unit further comprises at least one selection means,
Disturbance transmission type communication blocking device, characterized in that the target frequency band is selected by the selection means
According to claim 1,
The jamming wave transmission type communication blocking device is
Further comprising a handle portion and a trigger portion,
The trigger part is arranged so that the user's hand can manipulate the trigger part while holding the handle part,
Disturbance transmission type communication blocking device, characterized in that by adjusting the amplification gain (Gain) of the signal amplified by the amplification unit by the operation of the trigger unit.
5. The method of claim 4,
The amplification unit includes at least two amplification modules that can be connected in parallel to each other,
Disturbance transmission type communication blocking device, characterized in that the number of the amplification modules are connected in parallel to each other is controlled by the operation of the trigger unit.

According to claim 1,
The power supply further includes a battery,
The battery is a disturbance wave transmission type communication blocking device, characterized in that it is charged with 220V AC single-phase power connected from the outside.
According to claim 1,
The transmitter unit is a jamming radio transmission type communication blocking device, characterized in that it comprises a broadband antenna with an emission beam width of less than 20 degrees.

According to claim 1,
The jamming wave transmission type communication blocking device,
Disturbance transmission type communication blocking device, characterized in that it further comprises a filter unit for suppressing signals other than the target frequency band among the signals output from the amplifying unit and outputting the signal to the transmitting unit.
According to claim 1,
The jamming wave transmission type communication blocking device is
Disturbance transmission type communication blocking device, characterized in that it further comprises a shield-shaped external case
In the communication blocking method by the jamming wave transmission type communication blocking device,
determining a target frequency band;
generating white noise in an intermediate frequency band;
outputting a signal by up-converting the white noise of the intermediate frequency band into the target frequency band;
amplifying the signal;
transmitting the amplified signal to the atmosphere;
Communication blocking method comprising a.

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