1. When workers are working, from time to time, they will have incoming calls or text messages and stop their work to answer mobile phones or text messages.

 2. Some enterprises prohibit employees from playing mobile phones during working hours, but there are always individuals who take the opportunity to secretly use mobile phones.

 3. Some enterprise operation workshops need a quiet environment. Someone's mobile phone suddenly rings an incoming call, which disturbs the working environment and affects the working environment of surrounding colleagues.

 4. On some assembly lines, an employee's answering and making a phone call or checking his mobile phone will cause the whole assembly line operation, affecting the production efficiency.

 5. In some enterprises, the production and processing process, drawings, processing technology and product data are classified as confidential, but at any time, some employees may easily disclose the confidential data by using the smart phone to take photos, photos and other functions.

 6. Chemical enterprises that are explosion-proof and flame-proof products should strictly prohibit the use of mobile phones in the factory.

 To sum up, the universal use of mobile phones is a double-edged sword. Mobile phones have brought many uses to life, but for some special places, the use of mobile phones should be restricted or even prohibited. For example, the use of mobile phones is restricted in the workshop. According to the rules and regulations, personnel supervision, punishment system, etc., the use of mobile phones cannot be completely eradicated or eliminated. At present, the most effective and feasible way is to install intelligent jammer at appropriate locations in the plant. Each intelligent jammer can cover a certain range, and these coverage areas can be formed into the coverage of the area in the form of cellular networking To achieve the shielding of mobile phone signals in large areas