Techniques that deliberately interfere with electromagnetic frequencies (also known as interference) have been implemented in various devices, which are gradually provided to individuals and organizations. The interference is becoming smaller, more convenient, easier to use and cheaper, although in fact in most countries in the world, the interferencer is illegal. Although certain interferencers will block communication without differentials, there are several dedicated devices that are specifically designed to prevent certain signals. Among them, the most popular is the mobile phone jammer, WiFi interference, drone jammer, and even GPS interference.
In most countries, the authorities mostly disapproving the use of these devices is that they tend to have a greater impact than expected. Even deliberate use, for example to prevent the use of mobile phones in school, theater and hospitals, or prevent drone from flying over private property, or cause interference beyond the expected range. The 911 call is interrupted, the drone has fallen from the air and the air traffic control is damaged. This is some unexpected consequences of human interference. These interference has led to countries such as South Africa and Israel to completely regard these people.
Another reason is that the authorities hope to reserve proprietary control for these measures for law enforcement, security and military purposes. In the United States, Canada and India are some examples of prohibiting certain people (except for certain law enforcement agencies). Italy moves forward, even if these agencies can only operate the interference in the case of obtaining specific authorization. In Pakistan, Singapore and Iran, interferkers are only legal for people holding licenses and can assume that non-government entities do not easily get these licenses. This is not that rules always make sense. In the UK, it is legal if you have but not using a cell phone jammer.
The signal jammer is often used around prisons and detention to prevent prisoners from carrying out unauthorized and unmovable communications with the outside world. Brazil, India, New Zealand and Sweden are exempt or is considering the exemption of countries around the prison, while in the UK, since 2012 has become legitimate behavior.
However, some countries have allowed or have already proposed to expand the use of the interference. For example, in India, you can use an interference in the school, mosque, and theater, which can prove that interference does not exceed its interference range. In a short period of time, the interference was also approved for the theater and concert venue, but the interference was terminated in 2012.
So, what should I do if you finally have a mobile phone jammer? You may consider booking to ... Ukraine next flight. Since the government has taken active actions to prevent students from using mobile phones to check cheating, this is one of several few countries in the world using interference.