How to choose a high-performance test signal jammer?

How to choose a high-performance test signal jammer device? As we all know, a good test signal jammer needs to be involved in many aspects. Not only does the product have higher performance and better quality assurance, but it also needs to have an affordable price. After all, there are many choices of jammers on the market today, but Customers often want to choose the most satisfactory one from them. This is also for the purpose of achieving the most cost-effective consideration. So is there a manufacturer that can do this?

portable mobile phone radio jammer

For many schools, as the day of the college entrance examination is approaching, they are now preparing equipment and materials for the examination room everywhere. Among them, the test signal jammer is undoubtedly a very important one, because it is an effective way to prevent the examination room There are high-tech equipment for cheating. Therefore, schools are very cautious about the choice of cheating devices for exam signals. They must have professional strength and happy equipment. Among them, Beijing Shenzhou Mingda Company is a company that can provide customers with High-performance jammers, as a professional manufacturer, has brought more professional technical support to many customers over the years, made targeted research on customer needs, and finally gave customers products that can be implemented. Program. Friends who have doubts about purchasing are welcome to contact Beijing Shenzhou Mingda to consult the price of test signal jammers. Here are the best quality equipment and the most complete services. All products have undergone strict quality inspections, and each production process is treated almost harshly. Strive to bring customers the most outstanding products. After years of development, we have reached several cooperations with many customers and have been highly praised. It is a more wise choice. Welcome customers to come and buy.

New anti-drone guns impose order in the sky

In recent years, drones have become a rare pastime for amateurs. Now drones are everywhere, from people taking selfies, to commercial photography, to search and rescue missions.

Because of its ubiquity, accidents started to happen. The sky has become a drone infestation, and laws must be enacted to maintain order in the air, mainly in cities and airports. Due to their number and ability to carry all kinds of luggage, they have also become a serious threat to security expert review.

As mentioned earlier, it is not uncommon for drones to almost collide with aircraft, and drones equipped with cameras (or worse, explosives) may pose unique threats to the safety of the ground and facilities. However, in most cases, there are not many safe methods to deal with them.

Now, a new device that looks like a weapon in science fiction uses electromagnetic signals to knock drones out of the air quickly and safely.

drone jammer gun high power

Drone jammer guns are described as providing “safety countermeasures against various drone models.” It allows controlled management of UAV payloads (such as explosives) without causing damage to common UAV models or the surrounding environment. “This anti-drone device weighs about 8 kilograms and has an effective range of up to 1 km. It can be used on a rechargeable lithium-ion battery. As far as design is concerned, it will not be used by Stormtroopers in Star Wars movies.

It is very simple: you point the gun at the drone and pull the trigger. Transmit a series of electromagnetic signals and block the connection between the drone and its pilot. It uses radio frequencies to stop the drone from transmitting video and block the drone’s signal, forcing it to return to the launch point or land on the spot. “If the drone’s response is to go back to the beginning, this provides an opportunity to track it back to the operator.

Of course, there are other high-end technologies that can also attack aerial drones. It is an automatic defense strike system for drones.

Devices that can detect jammers are used by law enforcement

Humphreys is a University of Texas expert and is frequently consulted by law enforcement agencies and other government security experts. He said there may be other jammer incidents that have not been made public.
He said: “When I was questioned by the FBI, they often mentioned incidents of frequency jammer and even deception … but of course they did not reveal the details to me.”

Humphreys demonstrated how to use deception to use GPS for navigation to control a vehicle. In June 2012, he and several graduate students demonstrated the technology to Department of Homeland Security officials by commanding civilian drones; The following year, they had a larger run – a 213-foot superyacht – and tricked its GPS navigation system, causing the ship hundreds of meters to deviate from its course in the Mediterranean without issuing any vessel warnings.

gsm wifi jammer

Humphreys said these demonstrations require considerable effort and expense, and it is estimated that it took five years to develop “devices capable of simulating and then overwhelming real GPS signals.”

But last year, when Chinese technical experts showed the Defcon Hacking Conference how to use a $ 300 software radio to spoof a GPS, the situation changed dramatically.

Humphries said, “Now I have the ability to download what’s available online to a commercial RF card and build your own scooter.” “For those with little experience of RF work, it will only take a few hours.”

Humphries estimates that the result is that “since 2012, the difficulty of launching wave jammer attacks has decreased by about 100 times”.
Although interference “in the wild” is generally an annoying crime causing a brief interruption of the GPS or a fall of a cell phone tower when someone is nearby, the risk of cheating with inappropriate hands may be greater. tall.

As the head of NovAtel Soar said, “The runny-nosed kid in the bedroom can now be our worst nightmare.”
The police began to retaliate. Curry said, for example, that jammer detection equipment manufactured by Chronos Technology had been in use for about a year and “was starting to find a way to use it as standard.”

Prison security audit says mobile jammers are expensive

Given that an average of three cell phones are collected each day in state prisons, an internal prison security audit conducted by the state prison department found that the installation of the 4-G cell phone jammer and body scanners might not be of much help in suppressing harassment.

In addition to the estimated high cost and the frequent escalation of human interventions, authorities have also expressed concerns about the health of individuals and prisoners.

Police Director General Sinha said that even after investing heavily in complex technology, it was not a permanent solution. It costs around 1.25 crore and disrupts cell phone signals within a 30-meter radius, he said.

He said the assessment process was conducted after the higher courts in Punjab and Haryana ordered jammers installed in all prisons last year.
“As a pilot proposal to reduce the cost of human disruptors, we have identified 24 high priority areas in 14 prisons in which serious criminals are held. It is estimated that after spending 22 million rupees, we will only cover 10% of these prisons, leaving a large gray area, ”Sinha said.

Once approved by the secretary of the central cabinet (security) secretariat, it takes about nine months to purchase and install the jammer.

wireless military blocker

“As we explore cell phone jammer, technology upgrades accelerate 5-G. In this case, it will make these jammers unnecessary. Our assessment shows that the interference will affect people within two miles of the prison. However, mobile phone service providers are considering improving the signal for users living near prisons. In this case, we might have to spend more time indefinitely on the upgrade, which is a never-ending process. ”

The National Prison Service recovered 1,086 cell phones from various prisons in 2019. According to relevant officials, in January and February of this year, authorities only seized 580 cell phones.

“We recently launched a system where prisoners can use 10 different phone numbers to call for 10 minutes a day. We are designing more effective methods to monitor unauthorized use of cell phones in prisons,” the official said. .

The ADGP said that ensuring that the installation of the wave jammer does not lead to adverse effects on the health of prison staff is indeed a concern.

Sinha said the full body scanner costs around ₹ 3 crore and cannot detect the phone or anything hidden in the body cavity.

“Full body x-ray scanners are very effective at detecting any other object hidden in the phone, rectum or other body cavities. But there are no legal penalties in the country for the use of such. scanners in prisons, ”he added.

Drones and jammers are the biggest threat to airports

The Ministry of Civil Aviation has proposed a draft regulation that allows the use of drones for any purpose, but with certain restrictions.

While the Ministry of Civil Aviation has legalized the use of drones, government agencies are testing jammers that can disable drones that can pose a threat to safety.

A device designed to block drone communication systems is currently being tested at Delhi airport. Helicopters consisting of the Central Industrial Security Force (CISF) and the National Security Guard will also be dispatched as back-up personnel for emergency situations.

“Although the proposed guidelines for civil aviation state that the five kilometers around the airport is an uninhabited area, regulatory violations cannot be ruled out. Drones are typically managed by operators through a system of remote communication. The equipment we are testing will block the communication system., After that, the operator will no longer be able to control the drone.

Jammers Portable Handheld

The Home Office (MHA) plans to enact legislation to prevent the misuse of drones, especially near airports. Although airport security forces have been advised that drones are considered a potential security threat, no guidance has been issued on how to react when such aircraft are sighted nearby.

“Right now, drones are the biggest threat to airport security, with the exception of wave jammers. They are frequently observed and – currently there is no provision for shooting down flying objects. The CISF provides security, but has yet to decide who will deal with air threats. The Aviation Ministry will oversee the drone actions, but MHA must call for safety. ”

The source said MHA will issue a notice applicable to airports across the country.

The Ministry of Civil Aviation has proposed a draft regulation that allows the use of drones for any purpose, but with certain restrictions. Asked about safety, Aviation Minister RN Choubey said technology is being developed to neutralize rogue drones.

The ministry designated airports and international borders as unpopulated areas and stipulated that their use for commercial purposes requires special permits from aviation regulators. However, government agencies will not be bound by these guidelines.

The center invited the public to make suggestions within 30 days, then will make the necessary changes by December 31 to legalize the use of drones, and use drone jammer to prevent them if necessary.

Answer common questions about mobile phone signal jammers

1. Is there radiation?
If high-power equipment, such as 5W (37dBm) above the host computer may also have greater radiation. Generally, the output power of mobile phone signal booster is within 200mW (23dBm). After reaching the antenna, it is generally within 5mW (7dBm). After other losses, the indoor signal after installing a cell phone jammer is generally around -50dBm to -75dBm. Good outdoor signals are generally around -40dBm to -75dBm.

handheld blocker

When the mobile phone is talking, the GSM mobile phone is talking in a weak signal environment, and the worst radiation power can reach 1W (30dBm). After installing the amplifier, the radiated power of the mobile phone call is about 10mW (10dBm). It can also be said that after installing a small power amplifier in a poor signal environment, the mobile phone reduces radiation when talking.

2. How to distinguish the quality of signal amplifier?

1. Look at the workmanship and choose the brand. If you use more, you can take it apart and compare it internally.

2. There are many inferior signal amplifiers on the Internet, mainly because some circuits for optimizing signals, such as automatic gain control, are omitted. Generally, there are less than 80 devices, and the host with complete circuits generally has more than 200 devices.

3. Inferior cell phone signal amplifiers will cause serious interference to the base station after a large number of installations, making it impossible to make calls when the signal is full. Of course, there are interferences of good quality, but the interference of the same power is several times and dozens of times smaller.

3. Why can’t I make a call when the installation signal is full?

The signal amplifier is a simple device developed at the intermediate frequency of China Mobile and China Unicom. If there is no signal or very weak indoor China Unicom and China Mobile, it should be no problem to use this device. If one party has a full signal and the other has no signal, interference will occur in this case, so it is not recommended.

5G mobile phone signal jammer parameters

5G signaling is the hottest topic of the year, and the construction of 5G base stations across China has begun to implement 5G signal coverage. How convenient is it to use 5G signals? On the morning of May 10th, Hunan 5g Digital Industry Association and 5g + started the ceremony at Changsha Meishif International Cultural Arts Center, started the ceremony, Hunan Mobile and Xiang River, Hunan University, Xiang River Hospital, Banda Environment, Cool Wow Banda Partners have signed strategic agreements such as the establishment of a general 5g digital industry alliance to speed up the development of 5g application innovation. On the experience site, Revo, general manager of Hunan Mobile Changsha Branch, also passed the first 5G video call with Changsha City’s Tianxin District Committee standing member and Changsha City’s deputy director, State Shijun. .. We can think of how convenient 5G will bring to people.

As a new information technology infrastructure capable of providing at least 10 times the peak rate of 4g, transmission delays of millisecond, and billions of levels of connectivity, 5G is an automated driving, big health medicine, industrial internet, city of wisdom, Internet infrastructure for building things, high-definition video application scenarios to drive the Internet, big data fusion, artificial intelligence, and the depth of the real economy are critical to supporting high-quality development. is. It also brings about the rapid development of science and technology.

“3G, 4G, probably low and long wavelengths, at which high frequencies can resonate with some of the vibrational frequencies of water molecules and oxygen.” After the advent of 5G, future technological advances in 5G Not only do we need to enjoy the convenience and convenience, but we also need to pay attention to the effects of electromagnetic waves on the human body.

desktop cell signal blocker

China Mobile and China Unicom have issued a license to use mid-low frequency test frequencies in 5G systems. Among them, China Telecom and China Unicom have obtained licenses for test frequencies in the 3500MHz band, and China Mobile has obtained licenses for test frequencies in the 2600MHz and 4900MHz bands. Therefore, it is safe to use 5g jammer within the range. China Unicom and China Tele have secured a more international mainstream spectrum, but the story of China Mobile is much more complicated. In terms of subdivision, China Mobile has acquired 5G test frequency resources in the bands 2515mhz-2675mhz and 4800mhz-4900mhz. Of these, 2515-2575mhz, 2635-2675mhz, and 48800-4900mhz bands have been newly added, and 2575 bands have been added. -2635mhz prioritized China Mobile’s existing td-lte (4G) frequency.

Overview of wireless signal shielding principle of signal jammer

Let’s take a look at the overview of the principle of wireless signal shielding of signal jammers.

The working principle of mobile communication is that within a certain frequency range, wireless devices (mobile phones, etc.) communicate with the base station through radio waves, and complete data and sound transmission with a certain baud rate and modulation method. When the mobile phone communicates, it communicates with the base station through the uplink frequency, and then transfers the signal to the mobile service switching center to realize the call. In the standby state, the mobile phone communicates with the base station through the broadcast control channel. Once there is a call demand, it will be allocated to the mobile phone service channel according to the specific conditions of the channel near the terminal through the request, so that the mobile phone can jump to the service channel to realize the call and data transmission . At the same time, wireless communication must ensure a sufficient signal-to-noise ratio to effectively receive and complete communication.

desktop signal blocker

According to the above working principle, the cell phone signal jammer is generally composed of power supply, electronic scanning control unit, segmented radio frequency module unit, amplifier unit, transmitting antenna unit and other parts. The scanning signal generated by the signal generator passes the inverter, enters the oscillator and modulates it to the mobile communication working frequency band, and then is amplified by the power amplifier and the voltage regulator tube controls the power. The amplified frequency sweep signal is transmitted into the air in the form of radio waves. Because the frequency sweep signal forms garbled interference in the message signal received by the mobile phone (increasing the proportion of noise and noise signals to the device threshold), the mobile phone cannot receive the normal data sent by the base station, so that the mobile phone cannot establish a normal connection with the base station, thereby causing the mobile phone to disconnect Base station communication network. The mobile phone exhibits the phenomenon of no signal and no service system in the search network, which achieves the blocking effect. The mobile phone signal jammers produced by our company can achieve super high shielding effect, safe and simple.

The interference power of the jammer is fixed, and the shielding radius of the unblocked space is determined by the path attenuation and the signal level of the receiving base station. To realize interference from mobile phone signal jammers to mobile networks, it is necessary to ensure that the signal field emitted by the jammer is stronger than that of the mobile signal in the interference area. The closer the interference location is to the base station, the stronger the field strength and the smaller the effective interference area. , The farther the interference location is from the base station, the weaker the field strength and the larger the effective interference area.

It can be seen that within a certain transmit power, the interference range depends on the field strength in the interference area. No matter how powerful the jammer is, as long as the transmit power is a fixed value, as the distance increases, the interference signal strength will gradually attenuate and lose Interference ability. The following table shows the comparison table of distance and path attenuation. Then the output channel power of the jammer, the base station signal level, and the coverage line gain can determine the theoretical coverage radius with reference value.

Principle of signal isolator

In the industrial production process, a variety of instruments and meters are used in the monitoring and control of the generation process, which will generate a variety of signals: both faint small signals of millivolt level and tens of volts Large signals, even strong signals up to thousands of volts and hundreds of amperes; there are DC low-frequency signals, high-frequency or pulse spike signals; and these signals have to go through the process of mutual transmission and transmission, so how to ensure these signals In particular, the non-distortion of analog signals during transmission will become a problem that must be solved in system debugging.

Specifically, only when the analog signal transmission between the control device and the sensors and actuators distributed in the field is fault-free and undistorted, can the process control be safe and reliable. Especially low-power analog signals are affected by various external interference signals when they are transmitted in an industrial environment with high interference, and they need a reliable transmission channel. Daily work experience shows that due to equipment requirements, analog signals must be handled and transmitted carefully. However, the measurement and control parameters transmitted in the form of analog signals between the field and the control layer are often in a harsh industrial environment in the transmission project, which is likely to cause distortion of these signals.

smartphone signal blocker

Second, the principle of signal jammer

At present, the signal isolator (converter) is mainly divided into several kinds of isolation methods: transformer isolation method, photoelectric isolation method and transformer and photoelectric joint isolation method.

Signal isolators have a history of more than 40 years. Early signal isolators used transformer isolation. Its characteristics are: stable performance, long life, strong load capacity, high isolation strength, but the circuit is complex, and the manufacturing process requires higher.

With the development of electronic technology, in recent years, optoelectronic isolators produced by optical couplers have gradually appeared. Its characteristics are: stable performance, strong anti-interference ability, simple wiring and low cost, but compared to The transformer isolation method has a slightly shorter life.

In some occasions where the interference is large and the process requirements are high, the signal isolator of the combination of transformer and photoelectricity appears, and its isolation ability, resistance to unlimited radio frequency and electromagnetic interference is stronger.

How to make a signal blocking cellphone pocket?

For some at the National Republican Congress in Cleveland, the choice of protective accessory is an AR-15 rifle that is casually slung over the shoulder. For the Los Angeles-based artist and activist Tim Schwartz, it is a discreet pouch made of matt silver ripstop fabric that houses his cell phone.

This cell phone signal jammer blocks the signal that cell phones keep sending – a feature that Schwartz says is essential during an unpredictable, politically charged event like the Republican National Convention.

4g cell phone jammer

“I think it’s sensible that everyone should protect themselves when they get into a situation where they don’t know what’s going to happen,” says Schwartz. In particular, he states, “You can be easily followed by turning your phone on and off.” And if there is a disruption, the information could even be used retrospectively: “The government could request records and show that you were in this area when something went wrong.”

The Electronic Frontier Foundation, a non-profit organization dedicated to protecting civil liberties in the digital world, advises protesters that while their phones are powerful tools for documenting photos and videos, they also contain a wealth of personal information, including contacts, location and message history, emails and private credentials. “Our whole life is on our devices,” says Schwartz.

These high frequency blocking pockets, known as Faraday cages, are readily available to the powerful population that Schwartz calls the “techno elite.” Quartz reported on a $ 720 value of a cash transport and RF blocking bag, and President Barack Obama is traveling with a tent that serves that purpose.

For RNC protesters looking for a cheaper DIY option, Schwartz is holding “office hours” for protesters at the Spaces gallery in Cleveland to sew their own signal-blocking cellphone cases according to instructions from Berlin-based artist Aram Bartholl. Its meetings will take place today (July 19) and tomorrow from 1 p.m. to 4 p.m.

This is a protection that non-protesters could also consider, Schwartz says. “It’s like having long passwords,” he says. “It’s one of those things we should do, but we never get to it.”

Schwartz provided protesters with a copper taffeta fabric, a sewing machine and advice. He says his eighth grade sewing home economics training is appropriate for the job, and notes that the most important step is to make sure all of the edges of the bag are folded and secure.

Here are the directions from Aram Bartholl’s “Kill Your Phone” website. Materials are available on lessemf.com:

Cut 12 cm strips from your roll barrier fleece.
Make pieces of 50 x 12 cm, each for a bag. (i.e. you get 2 pieces of a 1 m long strip of rolls.)
Fold your 50 x 12 cm piece to 25 x 12 cm
Fold the long sides again, 1 cm each, and pin them in place with needles.
Sew two straight seams on the left and right.
Fold the opening at least 2 times! Find a paper clip or clip to close the pouch.
Done!
Schwartz previously developed a tool for victims of the Haiti earthquake to find their missing family members in 2010. He then “fell into the rabbit hole of digital privacy” and worked with the Center for Legal and Information Policy (CLIP) at Fordham Law School to investigate online privacy and reconcile it with security .

In recent years, Schwartz has conducted workshops on digital data protection such as “How to be a whistleblower” at schools like Cal Arts and UCLA, partly in collaboration with the web-based data protection movement Cryptoparty. For the remainder of the month, he will continue his work as an artist-in-residence at Spaces, where he is hosting events like a “dark web treasure hunt” to help people learn more about digital privacy.