Recently, the college entrance examination has been over for a while, and many candidates must know their scores. When reviewing the exam, will you find that there is no signal near the exam room during the exam? Cheating has always existed since ancient times, especially in ours. With the advancement of science and technology, cheating methods are emerging in an endless stream and become more sophisticated. Of course, we see more and more anti-cheating work. Our common ones include metal detectors, examiner checks, signal jammers and even fingerprint unlocking.
In fact, in the editor's opinion, signal jammers can be said to be the most sophisticated means. Especially in our era, the continuous advancement of electronic equipment can even evade detection. Nowadays, almost all cheating methods are people in the examination room carrying electronic equipment to talk about. The questions are output to the outside world, and then people outside the examination room answer the questions to achieve the purpose of cheating, and these all need to be spread through the network, at this time signal shielding is particularly important.
Of course, we see that signal cell phone jammer are actually not popular. They are only used in some important exams, such as college entrance examinations, national exams, and civil servants. The editor believes that signal jammers have good effects and low cost. In fact, they can be popularized. After all, metal detectors can't fully detect it in many cases. So how does a signal jammer shield the signal in this area? What is its working principle?
In fact, to put it simply, if we treat these cheating electronic devices as a two-way radio, playing the reception outside the exam room in the exam room, then the signal jammer is a jammer that makes your radio sound inaudible. Our mobile phones are these electronic devices. It needs to communicate with other devices through a base station, while wireless communication requires electromagnetic waves. According to the characteristics of electromagnetic waves, our devices need to be received within a certain frequency range, so the signal jammer is the electronic device that interferes with you The frequency of the two sides is different, so as to achieve the shielding effect.
Some people think that I don’t need a data network and I use Bluetooth and Wi-Fi. In fact, today’s signal jammers can be shielded from these networks. Bluetooth and Wi-Fi frequency bands have already been included in the scanning range, because in fact the data of each network And the Bluetooth wireless network is in different frequency ranges, and these are all included in the scanning range of the signal jammer, and this can be shielded.
The original signal jammer was designed to fight crime and serve law enforcement agencies and the military. So in fact, buying signal shielding on your own is also suspected of breaking the law. After all, the Powerful function of signal jammers may become a bad idea in the hands of criminals. In fact, we simply look at the principle of signal shielding, which is very simple and easy to understand. The shielding effect is achieved by interfering with different frequency bands.