Why does cell phone wireless signal jammer interfere with your cell phone signal?
Many users who use wifi jammer for cell phones do not understand the principle of operation and often overstep the frequency range when using them, resulting in improper use.
The working principle of mobile communication is that wireless devices (mobile phones, etc.) communicate with the base station via radio waves in a certain frequency range and terminate the transmission of data and sound with a certain rate. baud rate and a modulation method. The mobile phone communicates with the base station through the uplink frequency, then sends the signal to the cellular service switch to place the call. In the standby state, the mobile phone communicates with the base station via the broadcast control channel. Once there is a call request, it is assigned to the cellular service channel according to the specific conditions of the requested channel near the terminal, so that the mobile phone can access the service channel to realize the call and data transmission. At the same time, wireless communications must ensure a sufficient signal-to-noise ratio to effectively receive and terminate communications.
According to the above working principle, the cell phone jammer is usually composed of power unit, electronic scanning control unit, segmented high frequency module unit, an amplification unit and a transmitting antenna unit. The sampling signal generated by the signal generator passes through the inverter, enters the oscillator and modulates the working frequency band of mobile communications, then is amplified by the power amplifier and the voltage regulator tube controls the power. The amplified frequency sweep signal is emitted into the air as radio waves. Since the frequency sweep signal forms scrambled interference in the SMS signal received by the mobile phone (increasing the noise-to-noise signal ratio in the threshold of the device), the mobile phone cannot receive the data normally. sent by the base station, causing the phone to fail to establish a normal connection with the base station, resulting in the mobile phone being disconnected from the base station's communication network. The mobile phone has the phenomenon of no signal and no service system in the search network, in order to achieve the shielding effect.
The interference power of the jammer is fixed and the shielding radius of the free space is determined by the path attenuation and the signal level of the receiving base station. In order to realize the interference of the mobile wifi jammer on the mobile phone network, it is necessary to make sure that the signal field emitted by the jammer is stronger than the mobile phone signal within the interference range. The closer the location of the interference is to the base station, the stronger the field strength and the smaller the effective interference area. The further the location of the interference is from the base station, the weaker the field strength and the larger the area of effective interference.
It can be seen that within a certain transmission power, the interference zone depends on the field strength of the interference zone. Regardless of the strength of the interference, as long as the transmit power is a fixed value and the distance increases, the strength of the interference signal will gradually weaken and the interference ability will be lost.
