Wifi jammer is mainly for all kinds of examination rooms, schools, gas stations, churches, courts, libraries, conference centers (rooms), theaters, hospitals, government, finance, prisons, public security, military heavy places where the use of cell phones is prohibited. It is understood that the wifi signal jammer on the market now can be restricted from the transmitter 500M meters away, adjustable shielding radius, coverage of more than 30 ㎡.
Wifi signal jammer structure
Usually wifi frequency jammer consists of four major components are the transmitting antenna, sawtooth wave generator, voltage controlled oscillator, RF efficacy.
Wifi blocker working principle
Sawtooth wave control pressure-controlled oscillator, so that it generates the sweep signal of the working band, each sweep cycle, which is equivalent to adding a wide pulse (due to sawtooth wave positive range) and a narrow pulse (due to sawtooth wave reverse range) in each frequency point in the working band, which destroys the data exchange between the cell phone and the base station in the coverage area, the cell phone can not get the base station data, only show no signal, of course, it can not communicate.
According to the analysis, the sawtooth wave here is not used for measurement, just to allow the voltage controlled oscillator to work, do not what the accuracy, the use of the following figure shows a simpler circuit to generate.
Circuit diagram
The circuit is simple, the components are easy to obtain, the accuracy is not high, but can fully meet the requirements. Here, the accuracy of the lower return range of the longer sawtooth wave may also be better? The voltage controlled oscillator and RF amplification both operate at relatively high frequencies and have a lot in common.
