Everyone is very familiar with cell phone jammer. They are also called cell phone jammers. Anyone taking the comprehensive exam can see them. They are placed at the entrance of the examination room. On the contrary, this is not a malicious blocking signal, but a manifestation of maintaining fairness to provide people with a fair testing environment. However, sometimes many people want to know whether this will affect the signal radiation of the base station, so that there is no signal in an area.
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