Mobile phone signal jammer have become standard equipment in the examination room, not only for middle and high school entrance examinations, but also for postgraduate examinations, civil service exams and various qualification certificates. Mobile phone signal jammers are required to prevent candidates from contacting the outside world through wireless signals. In the test room using Dazhan Electronics' mobile phone signal blocker, various mobile phone signals (2345G), wireless intercom signals, Bluetooth WiFi signals, etc. will be blocked by interference.
So let's talk about cell phone signal jammers, why can they interfere with your cell phone signal?
We can compare a mobile phone to a radio for the time being. The radio often appears to be sizzling or the channel can’t be heard directly. This means that the signal is interfered. Since the radio can be interfered, so can the mobile phone. and interference through some devices.
Types of cell phone jammers:
Cell phone signal jammers have many different names, gps jammers，wifi jammers，drone jammers, cell phone jammers, signal jammers, cell phone signal jammers, cell phone signal blockers, cell phone isolators, cell phone cutoffs, mobile communication signal jammers, cell phone signals Degree shielding instrument, mobile phone jammer, signal jammer, mobile phone blocker, signal blocker, mobile phone signal isolator, signal isolator, mobile phone signal blocker, radio signal blocker.
How does a jammer work?
It uses frequency doubling, frequency division, frequency hopping filtering and other technologies to analyze the required shielding frequency for the uplink and downlink channels of the mobile phone system; customizes a spherical shielding space according to the power of the shield, and automatically forms a shielding magnetic field within the specified range. , so that the mobile phones (including PHS- PHS GSM-China Unicom, China Mobile, CDMA-China Telecom) in this space are invalid. When the jammer is in working state, it can disable the function of sending and receiving signals of mobile phones within a specified range, and cannot dial out or dial in, so as to achieve the purpose of mandatory disabling.
The principle of radio communication:
Within a certain frequency range, the mobile phone and the base station are connected by wireless electromagnetic waves to complete the transmission of data and sound with a certain baud rate and modulation method.
The communication principle of the mobile phone signal jammer, the jammer scans from the low-end frequency of the forward channel to the high-end at a certain speed during the working process. The scanning speed can cause garbled interference in the message signal received by the mobile phone, and the mobile phone cannot detect the normal data sent from the base station, so that the mobile phone cannot establish a connection with the base station. The mobile phone manifests as the phenomenon of searching the network, no signal, no service system, etc.
Now that we know that the communication method of wireless communication is to use electromagnetic waves to communicate.
The functional properties of electromagnetic waves are determined by their frequency.
The picture above shows the frequency range of the mobile phone signals of the three major operators that can be completely blocked by the Jammer mart electronic jammer. Our mobile phones must emit qualified electromagnetic waves in order to connect to our telecommunications carrier base stations.Different communication systems use different frequencies, so that everyone is safe and does not interfere with each other.
The Basics Principle of Cell Phone Jammers
The basic principle of cell phone jamming equipment is to emit the same radio frequency signal as the cell phone. Since the frequencies are the same, the cell phone cannot tell which signal is a regular base station signal, thus "jamming". As long as there is a machine on the same frequency as the phone, the base station will make a lot of "noise" when it tries to connect to the phone. You will find that the signal from the phone is unrecognizable, so you will refuse to communicate with the phone.In the early days, jammers only blocked one set of frequencies, such as 2G, while sophisticated jammers can block several types of networks at the same time, such as 2-3-4-5G.
So how is this multi-network interference achieved?
Actually simple. the interference bands corresponding to these three signals are repeated in a cyclic manner, covering these three interference bands at the same time. The interval of this cycle is so small that the mobile phone has no chance to speak, and can only sit and do it quietly. a brick.
2/3/4/5G covered, so what about bluetooth and wifi?
It doesn't matter, it can be easily done as well.The jammer has evolved again, adding the frequency bands of bluetooth and wifi to the scanning range, so that several common communication methods in the society are completely covered.
Many people do not understand the difference between Bluetooth, Wi-Fi and mobile data. They seem to be wireless communication technologies. In fact, the main difference between them is the frequency band. In mobile communication technology, 2G mainly works in the 900-1700MHz band, 3G works in the 1900-2100MHz band, 4G works in the 2300-2500MHz band, and 5G works in the 3400-3600MHz band. Bluetooth and WiFi work at 2.4GHz.
In this way, the R&D engineers of Jammer mart can accurately identify the communication frequency band and develop a mobile phone signal blocker with the same frequency band, so as to achieve the purpose of completely shielding the wireless signal of mobile phones, which is a sacred help for education and fairness in examinations.