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Friends who have some knowledge of frequency jammers know that a full-band frequency jammer will include at least ten or more signal jamming modules, and even some large jamming devices will be equipped with more than 20, Even more than thirty signal interference modules. Why is there such a large number of modules? Each of the signal interference modules is respectively aimed at a certain frequency range, and the span of the frequency range in each module generally does not exceed 200MHz or 300MHz. If the span of the frequency range is increased to 1000MHz or more, will the number of modules be reduced? Why doesn’t the frequency jammer use ultra-wideband jamming signal coverage?

The reason why we limit the frequency range of each module in the frequency jammer to 200-300MHz is the result of comprehensive evaluation and trade-offs. From the perspective of pursuing the best effect, it must be that the narrower the bandwidth, the better. The signal of the same power acts on a narrower frequency bandwidth, and the final effect is definitely better than broadband coverage. However, after narrowing the bandwidth, in the face of full-band, full-standard signal coverage, it is necessary to configure a large number of jamming modules for the frequency jammer, which will quickly increase the generation cost of the frequency jammer .

From the perspective of cost control and the number of modules and antennas that reduce frequency interference, making the bandwidth of the signal interference module as wide as possible will definitely reduce the number of modules, but the frequency span is not enough. Uncontrolled expansion, because the larger the span, the lower the average output power acting on the frequency band will be, which will directly reduce the final interference effect of the frequency jammer. At the same time, due to the increase in the frequency span, it is difficult to select the matching ultra-wideband power amplifier, and it also brings a lot of challenges to the selection of the ultra-wideband antenna. All in all, with the increase of the bandwidth, its real effect is inversely proportional to the decline.

The effective shielding distance of the mobile phone jammer is always the most concerned by customers! Some customers feel that the shielding effect is very good when they use it for a long time, and even the shielding distance exceeds the expected shielding distance. Using a shielding device is not enough to shield a room of 100 square meters. Why do you have these contrasting experiences? What are the key factors that affect the shielding distance of mobile phone jammers?

Generally, before buying a mobile phone jammer, when conducting pre-sales consultation with the manufacturer, the technical staff of the manufacturer will focus on reminding a key factor: the need to pay close attention to the location and distance of the mobile phone base station near the use site. Because the distance from the mobile phone base station will directly affect the final shielding distance of the mobile phone jammer at this use site. If there is a mobile phone base station within 200 meters or nearby, the manufacturer will directly inform that such a site environment is not suitable for installing mobile phone jammers.

The distance of the base station is one of the key factors, and the orientation of the base station must also be paid attention to. For example: even if there is a mobile phone base station at a relatively short distance near some use sites, if you stand in the window of the room and look towards the direction of the base station, you cannot directly observe the base station. There are other buildings in the middle. The building acts as a blocking effect, which will have a certain signal attenuation effect on the signal of the base station. In this case, using a mobile phone jammer may obtain a better shielding effect.

However, let’s change to another assumption of the environment: for example, standing in the window of the room and looking at the base station in the distance, even if the base station is more than 500 meters away, but because the base station can be directly observed visually, if the directional antenna on the base station is just right The front is facing the local area. Since there is no obstruction in the middle to attenuate the signal, if you turn on the mobile phone jammer in such a scene, you may find that the effective shielding distance is still very short.

Small commercial drone s have developed rapidly in recent years. During this development process, in order to pursue the ultra-high-speed flight and ultra-flexible maneuverability of drone s, some people have created flying speeds through customization or modification. Small unmanned aerial vehicles with extremely fast and excellent maneuverability are generally referred to as “shuttle unmanned aerial vehicles”. Then the question arises: Can the drone detection system effectively detect the shuttle drone?

To find out whether the drone detection system can effectively detect the shuttle drone, it needs to be analyzed from two aspects:

The first one is to analyze from the detection capability of the drone detection system itself. For example, a variety of common commercial small drone s of the “DJI” brand are currently a worldwide problem in the field of drone detection and identification. The combined application of various technical means such as detection technology cannot achieve 100% effective detection and identification. No matter what kind of detection technology is adopted by the drone detection system, it is difficult to avoid the problems of small commercial drone s flying low to the ground, using obstacles to fly around, flying speed can be fast or slow, and the size of the identifiable target is too small. Each method of detection technology has advantages and disadvantages, and the ability to detect and identify is also strong and weak at times.

The second is to analyze from the characteristics of the shuttle drone itself. The drone detection system is still unable to achieve 100% detection of targets when detecting conventional small commercial drone s. If it is used to detect shuttle drone s, the current ability of drone detection systems is almost completely lost. improved detection capabilities. The current shuttle drone can achieve a speed of more than 300Km/h. In terms of maneuverability, it can suddenly turn, stop, and go up and down in a state of high-speed flight. Many actions are almost against aerodynamics. , it can be released in the form of a catapult take-off like a cannonball, and quickly approach the target. In the face of such a shuttle drone with such excellent performance, the detection capability of the drone detection system cannot keep up in time.

From the known product information of various mobile phone jammer manufacturers, we can hardly see any product that can claim that its effective shielding distance can reach more than 1000 meters, and we usually receive project consultation questions However, there are often customers who ask us to purchase or customize a special mobile phone jammer. There is no other restriction, but there is only one requirement: that is, it must be able to effectively shield the distance of 1000 meters. The question arises: Is it possible to make the shielding distance of mobile phone jammers reach more than 1000 meters?

Customers who put forward such requirements to us sometimes give an analogy: the base station coverage radius of some mobile phones can reach 2-3 kilometers, and high-power mobile phone jammers also emit radio frequency signals, and their effective shielding distance reaches Is it difficult to go above 1000 meters?

The reality is: under the condition of acceptable and reasonable production cost, it is almost impossible for conventional high-power mobile phone jammers to achieve an effective shielding radius of 1000 meters or longer. a difficult problem.

First of all, let me explain that the base station of a mobile phone can cover a radius of 2-3 kilometers, or even farther, because the frequency bandwidth of the base station is limited. Usually, the transmission power of the base station is 20W or greater, but the base station’s The bandwidth of the frequency band is not large. The traditional 2G bandwidth is less than 1MHz bandwidth, and the frequency bandwidth of 3G and 4G is only 4MHz to 20MHz. Under the effect of high power and narrow bandwidth, the mobile phone signal covers a range of several kilometers No surprise. But in the 5G era, the bandwidth of 5G will reach dozens of MHz or even 100MHz. Friends who understand the technical performance of 5G will also know that the mobile phone signal coverage of 5G base stations generally cannot reach more than 1,000 meters. This is why the construction of 5G base stations is becoming more and more intensive and the number is increasing.

High-power mobile phone jammers will also encounter this problem. If it wants to ensure sufficient mobile phone shielding effect, the shielding signal it transmits must be 3-5dB or more higher than the signal of the mobile phone base station. However, mobile phone interference Every signal shielding module in the device is a broadband signal output, and the frequency bandwidth of almost every shielding module will exceed 50MHz or even 100MHz. Even if the total power of the modules is 50W or even 100W, the average output power value of each module will be reduced due to the large bandwidth.

In recent years, 5G jammers have begun to sell well, which is in line with the rapid popularization of 5G communication technology. However, more and more customers have also begun to receive feedback, saying that they have selected 5G jammers from some brand manufacturers. , in actual use, it is found that the shielding effect is not very ideal, and the real shielding distance is only a few meters away. These customers want to get good solutions from us, so how should 5G jammers solve the problems that are not effective?

When using the field to test the actual shielding effect, it is found that the shielding distance is very short, which needs to be analyzed from two aspects: the first is to focus on the analysis of the field environment, that is, it is necessary to focus on understanding the distribution of base stations around the place of use, And the distance from the mobile phone base station to the site of use. For qualified customers, it is recommended to invite the manufacturer of the 5G jammer to carry a professional spectrum analyzer or field strength signal analyzer, etc., to retrieve the spectrum of the mobile phone signal on the spot, detect the signal strength of the mobile phone, and make a comprehensive evaluation based on this , so as to judge whether the shielding effect is not good because the base station is too close and the base station signal is too strong. According to years of experience in the past: if it is clearly known that there are mobile phone base stations within 200 meters of the surrounding area, it is basically not recommended to install and use 5G jammers on such sites.

The second aspect that needs to be analyzed is: Is the 5G jammer itself that has been selected and purchased suitable? What you need to know here is: How many 5G shielding modules are there for the 5G standard in this 5G jammer? Has the actual output power of each 5G shielding module reached the standard output value? Today, if you want to achieve a 5G jammer that fully covers the 2G, 3G, 4G and 5G signals in the mobile phone, the number of shielding modules required should be no less than 10. If you need to obtain a better 5G shielding effect, you should Consider appropriate splitting of some 5G shielding modules whose shielding signal coverage bandwidth reaches 100MHz or more, such as splitting the 100MHz bandwidth into two 5G shielding modules with a bandwidth of 50MHz, which will improve the shielding effect of 5G jammers. Definitely beneficial.

The so-called portable frequency jammer, the portable functional characteristics are mainly reflected in its small size, easy to carry or fast transfer. Another obvious functional feature is the diversity of power supply methods. In addition to the most basic AC power supply method, it usually also has a built-in large-capacity rechargeable battery. In some wild places or working environments where AC power supply cannot be obtained, The built-in battery can be preferentially used for power supply. Then the question comes out: how long should the battery power supply time of the portable frequency jammer be?

The first thing to understand is that as long as the portable frequency jammer is used in the outdoor environment, it is generally a high-power model. High power refers to the RF power value of the output port of the signal interference module in the device. The RF power is greater than 30W. , basically belong to the category of high power. Since the radio frequency power is very large, the corresponding power consumption will also be very large. The ratio of radio frequency power to power consumption is about 1:2 or 1:3. It can be seen that the power consumption of a high-power signal interference module is about 100W.

The total power consumption of a portable frequency jammer depends on how many signal jamming modules are configured in the frequency jammer, and each signal jamming module corresponds to a different frequency range. Let’s take the mobile phone signal as an example, or we need to completely interfere with all 2G, 3G, 4G, 5G signals in the mobile phone signal, as well as WI-FI2.4G, WI-FI5.8G, and at least 12 signal interferences need to be configured Module, so it can be calculated that the total power consumption of this portable frequency jammer for all mobile phone signals is about 1200W, that is, the power consumption of this device for 1 hour is 1.2 degrees.

Back to the question raised at the beginning: how long should the battery power supply time of the portable frequency jammer be? Some customers often answer directly: Of course, the longer the better! Can it be battery powered for half a day (6 hours or 12 hours)? The answer that is more in line with the actual situation is: Considering that the increase in battery capacity will inevitably increase the weight of the battery itself, it will also increase the space occupied by the battery. When these two factors are superimposed repeatedly, it will inevitably affect the frequency jammer. Important “portable” functional attributes? The expedient result after the final comprehensive consideration is: within the acceptable range of weight and size, the optional built-in rechargeable battery, the power value is in the range of 1000W-2000W, converted into effective power supply time, that is, it can allow The portable frequency jammer works continuously for 1-2 hours.

Among the questions that customers ask us about our products, there is a question that customers are most likely to ask and want to know the answer most urgently, which is: we want to purchase super-power mobile phone jammers and require the coverage of jamming signals Can reach more than 1 km. In the face of such urgent inquiries from customers, we are actually not willing to tell them with a clear negative answer, and we can only explain the reason patiently. Here, we will focus on explaining why the interference range of mobile phone jammers cannot reach 1-2 kilometers.

From the conventional understanding, the greater the power of the mobile phone jammer, the greater the coverage of the interference signal. However, since the transmit power cannot be increased without limit, there is an upper limit. Nowadays, in a set of high-power mobile phone jammers, in order to achieve a completely effective jamming effect for various mobile phone formats, 10-12 high-power mobile phone signal jamming modules must be installed at the same time, corresponding to the mobile phone’s For each communication frequency band, the transmission power of each signal interference module is determined by the maximum output power value of the power amplifier device. At present, the available power values of power amplifier devices are mostly 50W or 100W, and very few can reach 200W. It is not that there are no power amplifier devices with larger values, but because the usage is very small and the cost is too high. In addition, due to the increase in the power value of the power amplifier device, the overall power consumption of the device will also increase rapidly, which will also lead to the need to increase the heat dissipation performance of the device. For example, adding a radiator will also cause the volume and weight of the device to increase. increased badly.

According to the above analysis, the upper limit of the RF power of the interference module in the high-power mobile phone signal device is 100W, and the maximum can reach 200W. In the case of this output power value, in the conventional application environment, its effective coverage radius is about 200 meters to 500 meters, but we must understand that: the effective interference range of mobile phone signals is actually different from that in the surrounding environment. The base station distance is closely related. As mentioned earlier, the interference range in a conventional environment can reach 500 meters or more, but this is an ideal usage scenario. In the real urban living environment, due to the increasing density of base station deployment , If you want to find an environment where there are no base stations within a few kilometers, it is already difficult.

So the final conclusion is: even if it is a mobile phone jammer with high power, its interference range is almost impossible to reach 1-2 kilometers.

Since 2019, 5G signal jammers have developed simultaneously with the rapid popularization of 5G mobile phones. Just as mobile phone users gradually abandon the original 4G mobile phones and buy new 5G mobile phones, those who have purchased 4G signal jammers before Customers have also begun to purchase and install 5G signal jammers in recent years. The key point that customers pay attention to when selecting products is not only to maintain the original 2G, 3G, 4G mobile phone signal shielding function, but also to ensure the shielding effect on 5G signals. Then the question arises: Which 5G frequency bands should at least be included in the 5G signal jammer?

According to the division of the 5G mobile phone communication frequency band by the radio authority, taking my country as an example, the frequencies used by 5G mobile phones include: the 758-788MHz frequency band belongs to China Radio and Television, the 2515-2675MHz frequency band belongs to China Mobile, and the 3400-3500MHz belongs to China Telecom, 3500-3600MHz belongs to China Unicom. The four 5G frequency bands listed here are all 5G signal jammer manufacturers will inevitably choose and install the corresponding 5G signal shielding module.

In addition to the above four 5G frequency bands, there is also a frequency band of 4800-4960MHz, which is allocated to China Mobile and China Radio and Television. It is used for the construction of private communication networks in some special places, and it is almost impossible to deploy base stations in the 4.8G frequency band in daily life. Because of this, most of the manufacturers of 5G signal jammers choose not to install signal shielding modules for the 4.8G frequency band from the perspective of saving and controlling production costs.

When some customers confirm the technical indicators of the high-power vehicle-mounted frequency jammer with us, they often ask such a question: After modifying the vehicle, the frequency jammer is installed in the rear trunk area of the car, but they do not want to install a generator , but use the method of installing a large-capacity battery in the car to supply power to the interference device. I want us to confirm whether such a power supply method is feasible.

When formulating a vehicle modification plan for a vehicle-mounted frequency jammer, it is indeed necessary to consider the power supply method of the device, and our first recommendation as a manufacturer of jamming equipment is to recommend the selection of a vehicle-mounted generator that matches the power consumption of the jamming device . Simply relying on the battery to supply power to the interfering device, if there is no special reason, this option is not recommended.

Now common high-power vehicle-mounted frequency jammers, if they are full-band, are usually equipped with 18-24 jamming modules, and the power consumption of the whole set of jamming equipment will reach 4KW to 6KW. The value of this power consumption is relatively large, which is equivalent to providing 4-6 kWh of electricity per hour. If this kind of power consumption is completely powered by the battery, considering the continuous power supply time of the battery to the frequency jammer, it should be able to work stably for more than 2-3 hours. Then in conversion, if a 24V battery pack is used, the power of the battery pack must be required. The total capacity reaches 500-600Ah. Even with a 48V battery pack, the total capacity needs to be about 300Ah. Friends who are familiar with battery packs should know that the volume and weight of such battery packs are quite scary when stacked together.

If the battery pack calculated according to the above data is installed in the car, even if the volume factor is not considered, it is a very serious problem to distribute the weight of hundreds of kilograms in the car separately. Moreover, the battery pack with such a capacity , there is still a certain security risk.

The battery supplies power to the interfering devices, and a DC-to-AC inverter needs to be added in the middle. An inverter that can meet such super-high power is not a good choice.

Therefore, in summary, we do not recommend that the vehicle-mounted frequency jammer is only powered by batteries.

In some occasions that need to restrict the use of mobile phones, installing and using signal jammers is a relatively routine and feasible implementation method, so some customers have questions: signal jammers have a shielding effect on mobile phone signals, so for mobile phones Do the various APPs of the company also have a shielding effect?

In fact, in the actual application scenario, when the mobile phone is within the effective coverage of the signal jammer, the most intuitive feeling for mobile phone users is that the mobile phone will be offline, that is, there is no signal displayed on the mobile phone. At that time, there is no connection and communication between the mobile phone and the base station. If you make a call at this time, you will find that the mobile phone cannot be dialed out at all, and of course there will be no external calls. Dial to this mobile phone. At the same time, it will also be found that the state of many APP software on the mobile phone will be somewhat different compared with the past. For example, chat and communication software will prompt that it is offline. When viewing audio, video and other playback software, the content of audio and video programs on demand will not be played. When browsing news websites, you will find that news items cannot be refreshed to update content and so on.

As for the question mentioned at the beginning: Will the signal jammer block the APP application software? This depends on how to understand the application of the software. Because the signal jammer actually shields the signal of the mobile phone, making the mobile phone lose the ability to communicate with the outside world. The shielding function mentioned here refers to signal shielding. The various APP software on the mobile phone can actually be opened and run normally, but due to the loss of real-time networking communication capabilities, although the software can run normally, it cannot update data or communicate with the outside world. Some audio and video software can still play local files stored on the mobile phone even when the signal is lost.

As Russia and Ukraine’s special military operations have entered a continuous stalemate, news reports on the two sides’ repeated introduction of drones into combat operations are common, especially recently, it has been exposed: the Russian Kremlin encountered a suspected Ukrainian dispatch of drones The terrorist attacks, as observers of other countries who stay out of the way, are aware of the importance of drone defense issues, and the use of drone jammers is basically the same for drones that invade and prepare to create attacks. It can be said to be the most convenient, efficient and effective trump card. As a professional manufacturer of drone jammers, we have recently experienced a significant increase in the number of customers visiting and consulting. Some of the customers’ demands are very direct and clear, requiring us to maximize the transmission power of the drone jammer, in order to maximize the interference range for the drone, so as to ensure sufficient protection area. Then the question arises: Is the jamming range of the drone jammer as large as possible?

Our point of view is that the larger the interference range, the better. We should choose the appropriate transmission power according to the actual use environment, and the requirements for coverage are just enough. In the current drone jammer products, the jamming modules of multiple common communication frequency bands of drone s usually have several power grades according to the size of their transmission power: 5W, 10W, 20W, 50W, etc., as the power increases one by one , the corresponding interference range is gradually increasing, especially for drone jammers with 50W or higher power, the effective interference range will reach 3Km or even more than 5Km.

If it is really like the battlefield environment where Russia and Ukraine are actually fighting, the jamming range of drone jammers reaches more than several kilometers, which is definitely an urgent need, and there is no need to consider the influence of any other external factors, after all The safety of protection is the primary goal. However, if you switch to a non-combat environment in another country, when defending drones, you need to consider the problem that the interference range of drone jammers should not be too large. The main reason is: drones The multiple interference signals in the jammer will affect the common electronic products of ordinary people, such as GPS navigation and positioning signals, WI-FI 2.4G and WI-FI 5.8G wireless network signals. If the power of the machine jammer is too large, the coverage of the jamming signal will be too large, which will bring unnecessary troubles to the lives of too many ordinary people who should not be affected.

In the application field of mobile phone jammers, if it is divided according to the coverage direction of the shielding signal, there are two basic classifications, namely: omnidirectional antenna coverage and directional antenna coverage. By default, the standard configuration of the low-power mobile phone jammer is an omnidirectional antenna, and the high-power shielding device will choose whether to use a directional antenna or an omnidirectional antenna according to the actual usage scenario. Some customers will ask questions: Can the two types of antennas be configured at the same time for the antenna in the mobile phone jammer, and can it be quickly switched to directional or omnidirectional when in use?

The customer’s idea seems simple, but it is not easy to realize it on the mobile phone jammer. During the transmission of radio frequency signals through radio frequency cables, it cannot be simply understood as circuit switching like electrical circuits. The switching of radio frequency signals requires a power divider or a dedicated radio frequency switch, but such a radio frequency switch has very few application scenarios, and there are very few devices to choose from. At the same time, there are two other reasons that limit the possibility of adopting Power switching method: The first reason is that after the RF signal has undergone a power switching switch, at least two RF interfaces for signal input and output will be added. Every time an RF interface is added, the RF signal will experience signal attenuation. This will cause the effective output power of the mobile phone jammer to be further reduced. The second reason is that each mobile phone jammer will include at least 10-12 signal shielding modules of different frequency bands, and each shielding module needs to correspond to a set of directional antennas or omnidirectional antennas. If you want to complete the switching of radio frequency signals function, it is necessary to add radio frequency switching switches to the output terminals of these 10-12 signal shielding modules, which will undoubtedly greatly increase the production cost of mobile phone jammers.

Based on the above analysis, it is not impossible to quickly switch the antenna of the mobile phone jammer to a directional or omnidirectional mode at the moment, but considering the overall production cost, the customer’s budget and the actual demand are not large, so each mobile phone Jammer manufacturers have not invested energy to achieve such functional requirements.