Wifi signal jammers generally consist of a power supply, electronic scanning control unit, segmented radio frequency module unit, amplifier unit, transmitting antenna unit, etc. After the signal generator generates the scanning signal, it enters the oscillator and adjusts it to the mobile communication operating frequency band, and then amplifies the voltage and controls the power through the power amplifier. The amplified scanning signal is emitted into the air in the form of radio waves.
Since the scanning signal forms disordered code interference in the newspaper signal received by the mobile phone (raising the noise-to-signal ratio to the device threshold), the mobile phone is unable to receive normal data sent by the base station, making the mobile phone unable to receive normal data. The mobile phone cannot establish a normal connection with the base station, causing the mobile phone to be separated from the base station communication network. The mobile phone shows symptoms such as no signal and no service system in the search network to achieve the blocking effect.
The working principle of the wireless signal jammer is to scan the low-end frequency of the channel at a certain speed. When the mobile phone receives the newspaper signal, the scanning speed will form disordered code interference. The mobile phone cannot detect the normal data sent by the base station, making it impossible for the mobile phone to establish contact with the base station, thereby blocking the mobile phone signal. Mobile phone performance is searching the network, no signal, no service system, etc. The interference power of signal shielding is certain.
The shielding radius of the unobstructed space is determined by the path attenuation and the signal of the receiving base station. In order to interfere with the interference of the cell phone signal jammer on the mobile network, it must be ensured that the signal field emitted by the jammer is stronger than the interference area. Mobile signal field. The closer the interference field is to the base station, the stronger the field and the smaller the effective interference area. On the contrary, the farther the interference field is from the base station, the stronger the field and the larger the effective interference area.
It can be seen that in a certain transmit power, the interference range depends on the intensity of the interference area. No matter how high the signal shielding power is, the strength of the interfering signal will gradually decrease as the distance increases, thus losing the ability to interfere.