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You can buy a jamming device and have it with you

The cell phone jammer scans from the low frequency band of the forward channel (the channel from the base station to the mobile phone) to the high frequency band at a certain speed during the working process, and forms interference when the mobile phone receives the message signal. The normal data sent from the base station cannot be detected, so that the connection with the base station cannot be established, and there is no signal and no service state. For example, when the mobile phone communicates with the base station, the signal jammer is like a messenger, deliberately making noise around you. The noise signal is so large that the mobile phone can't understand what the base station is saying, and the mobile phone can't hear what the base station is saying.
http://www.jammer-buy.com/cell-phone-jammer/c-24.html

The benefits of home wifi mobile phone signal jammers are to ensure network security on the one hand, and on the other hand, it can also control the time that children use the Internet.The wireless network facilitates people to access the Internet, but the problems caused by it cannot be ignored. This is not only a problem of accessing the network, but also a problem of network security. In order to maintain a good network environment, many places have installed wifi shields to prevent excessive use of the network. This equipment has been widely used in countries and regions around the world. Schools, prisons, libraries, reading rooms and gas stations are typical representatives.
http://www.jammer-buy.com/wifi-jammer/c-29.html

To understand how the GPS blocker works, it will be helpful to be familiar with how GPS works. GPS stands for Global Positioning System and works through the GNSS network (Global Navigation Satellite System). The GPS tracker is connected to the GNSS network. GPS signal jammers send out radio signals at exactly the same frequency as GPS devices, which overwrite the signals sent by satellites. In this case, the GPS tracking device cannot determine its exact location because the scrambler is interfering with its signal.
http://www.jammer-buy.com/gps-jammer/c-25.html