What is the principle of the mobile phone signal jammer in the examination room? Does it work?
The principle of wireless signal jammer
Now our mobile phone 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 need for a call, the mobile phone will first be assigned to the mobile phone business channel according to the specific conditions of the channel near the terminal through the request, so that the mobile phone will jump to the business channel to realize the call and data transmission. .
At the same time, 4g wireless communication must ensure sufficient signal-to-noise ratio to effectively receive and complete the communication.
Then according to the above working principle, we can conclude that the 4g wireless 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. After the signal generator generates the scanning signal, it goes through 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 scanning signal is transmitted into the air in the form of radio waves.
The wireless signal jammer forms garbled interference in the received message signal of the mobile phone due to the frequency sweep signal (increase the ratio of the noise signal to the device threshold), the mobile phone cannot receive the normal 4G data sent by the base station, so that the mobile phone cannot establish a normal connection with the base station. , so that the mobile phone is disconnected from the base station communication network. The mobile phone shows the phenomenon that the search network has no signal, no service system, etc., to achieve the blocking effect.
Can the test room signal blocker block 4G signals?
Today's society is developing faster and faster, the most obvious is the progress of science and technology. It is inevitable that the 4G era will replace the past 3G and 2G. Now 4G is not hot, and 5G is emerging again. However, 4G signals are still the mainstream. So, can the signal shielding of the examination room shield the 4G signal? This is a very critical question. In fact, the new test room signal blockers on the market have been upgraded, and blocking 4G signals is almost standard. However, some of the cheaper test room signal blockers on the market can only block 2G or 3G signals.
People who don't know this industry are likely to be fooled very easily. The signal blocker in the examination room that shields the 4G signal must have at least eight antennas. At present, eight-wire shields are divided into two types, one is an external antenna, and the other is an internal antenna. The two are well differentiated. The one with antennas is similar to the router, but it has more antennas than the router. As for the built-in, it is the size of a set-top box. Just plug it in directly. Most 8-wire shields can shield many types of signals. Some can even block 5G signals. In order to help customers solve their problems, HiSilicon has built a space for shielding 5G signals in the new signal blocker in advance. In this way, even if the 4G era ends, there is no need to replace the hardware facilities. Therefore, in this way, the cost can be greatly saved for the customer.