A signal jammer is essential in many places, but many people do not know how to install cell phone jammers. Some believe that the jammer can be connected directly to the power supply, others believe that the frequency should be adjusted. It’s hard to tell if a cell phone jammer is working or not, so let’s look at the jamming principle.
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Interference in adjacent channels.
Adjacent channel noise refers to signal noise at frequencies adjacent to the signal frequency being used. Adjacent frequency interference is caused by perfect coupling, causing the adjacent frequency signal to leak into the transmission bandwidth.
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The near-far effect.
This problem will become very serious if an adjacent channel base station transmits at very close range to the user receiver and the receiver uses the base station signal of the set channel, which is called the near-far effect.
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Intermodulation test.
When two or more signals with different frequencies are applied to a non-linear circuit, the output signal with the new frequency will modulate each other. If the frequency falls within the bandwidth of the operational channel of the receiver, it will cause interference in the receiver, causing intermodulation noise.
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Try to block.
Each receiver has a specific receiver dynamic scale. When the interfering signal outside the frequency band is strong to some extent and the received power exceeds the greater power level promised by the receiver dynamics, the receiver will be completely blocked used ps4 for sale, thus affecting the system reception function. This interference is called a blocking attempt. Blocking causes the receiver to malfunction, and prolonged blocking may result in decreased receiver functionality.
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False interference.
Due to the rolling properties of the emission filter, there will always be a certain amount of out-of-band radiation, this is what we usually call false emission. Spoofed interference from emissions is called fraudulent interference.
Interference between mobile communication systems.
- Internal interference: The signal transmitted by CDMA acts directly on the GSM receiver as in-band noise, either directly or via intermodulation, thus reducing the sensitivity of the GSM receiver. These disturbances are divided into unwanted emission disturbances and intermodulation disturbances;
- Out-of-band interference: When the out-of-band interference is strong enough, it will completely block the receiver, thus affecting the reception function of GSM system. This interference is also called a jamming attempt.
Using a cell phone jammer is convenient for our life, but its signal is easily interfered with, so we still need to adjust its frequency.