When ordinary civilian cell phone jammer are used in places with strict cell phone protection requirements, such as prisons, they exhibit the following manifestations:

1. The armor effect of the armor area is weak and there are more blind areas and blind spots. Some areas near the cell area window, especially on the base station side, can also be connected to cell phones under certain antennas (devices). Phones provide opportunities for criminals, but they cannot completely prevent the illegal use of cell phones.

2. This area should not be protected. Serious incident: The office building and armed police outside the second prison door were seriously disrupted, affecting the normal life and work of staff. The most serious interference zone is still extended and even the base station is crippled by the interference. Large areas of communities, factories and units have been severely disturbed and there have been numerous complaints from the public. Complaints from residents and operational departments such as China Mobile, China Unicom and China Telecom, as well as investigations by local radio management departments, to some extent affected the normal functioning of the prison and disturbed the harmony between the prison. police and the population. .

3. Unstable system operation: good times and bad, poor reliability and frequent breakdowns. Especially in summer and autumn there is a lot of equipment failure and damage, but after a large number of equipment replacements, the expected shielding effect cannot be achieved. In return for continued maintenance, life and money were exhausted.