Call On Cell Phone From A Blocked Number Affects Call Quality

Although the time of the college entrance examination this year was affected by the epidemic and was postponed to July 7-8, in order to ensure the security of information in the examination room, the corresponding measures have not been reduced at all. Operators have issued announcements one after another. During the exam, they will turn on wireless Call On Cell Phone From A Blocked Number according to the requirements of the Education Bureau, which will affect the communication quality of mobile phone users around the school. The communication will not return to normal until the end of the exam. What is the effect of opening cell phone jammer during the college entrance examination? The invigilator at the entrance of the examination room is waving a metal detector. Is it really useful? To know what exactly blocking cell phone signals does, let's first understand how mobile communications work. As a mobile communication device, a mobile phone needs to establish a connection with a nearby base station first, and then access the core network to find a communication destination. In the above process, all information is carried and transmitted by electromagnetic waves. The electromagnetic wave frequency band used by the mobile phone is related to the standard and operator of the mobile phone. But in general, the electromagnetic wave frequency bands used by the three operators are distributed in the 850-4900MHz range. If the organizer of the college entrance examination wants to block the mobile phone signals in the examination room, it is impossible for the 2G/3G/4G/5G base stations near the examination room to not work, otherwise all the communication equipment in this area will not be able to communicate normally. That's the only way to block cell phone signals in the exam room.

There is a kind of bad signal, called the two days of the college entrance examination. As a heavy mobile phone user, the battery and signal of the mobile phone are the life tank. For such heavy mobile phone addicts, the most unhappy days of the year are the three days of the college entrance examination. In the short three days of the college entrance examination, in addition to the uninterrupted news reports and the unprovoked crowding when passing the test center, the most impressive thing was the poor mobile phone signal due to the use of Call On Cell Phone From A Blocked Number during the test. What is the sacredness of the mobile phone signal shielding device? Today, let's trace the ins and outs of this artifact together. At first, everyone was happy when the cell phone jammer appeared. At first, the jammer was not actually set up for the exam scene. The original application of cell phone jammers was actually prisons. Prisons need physical and information isolation. In order to ensure the information security and privacy of the prison's high-wall compound, it is necessary for the prison to isolate the communication signals between the prison and the prison. This is the original intention of the cell phone signal jammer. When the signal jammer was first invented, the whole world was only in the 2G era. At that time, although there were three operators in China, all mobile phones used the second-generation network communication technology. The communication frequencies of mobile phones used by manufacturers of different standards are quite different.