By the annual exam season, all parties have begun to prepare for the exam, and the invigilator has various tricks to prevent high-tech fraud. Among them, the shielding device used in the examination room is still an anti-fraud shielding device. However, Chengdu Saiyue Communication reminds that there are many types of shielding devices, and users should clarify their needs before purchasing them to avoid test room accidents due to poor shielding effects, and pay attention to the correctness of the method of use.
First of all, I want to clarify the place of use. Most schools use test room-type mobile phone shields that are suitable for long-term work and are durable. The second is how big are we in the shielded area? For example, if it is a room of 100 square meters or a venue of thousands of square meters, if the area is large, the power must be larger, and if the area is small, the shielding power must be considered small. Then there is which frequency bands need to be shielded. Are all China Mobile, China Unicom, Telecom and CDMA shielded? Still only need to shield part of the frequency band.
At this time, we remind everyone that if you want to buy a suitable shielding device to achieve the effect, it depends on the method used. The main points are as follows:
1. It is recommended that the indoor shielding device be placed at a height of about 180cm-220cm above the ground, with a forward angle.
2. Whether there are obstructions (such as walls, metal products, etc.) between the wireless jammer and wireless communication equipment (mobile phones, etc.). The interference signal emitted by the jammer will be attenuated to different degrees after passing through the obstruction, please try to avoid it.
3. The weaker the wireless communication signal strength in the use environment, the stronger the theoretical shielding effect of the shielding device.
4. The farther the jammer application environment is from the signal tower, the stronger the theoretical shielding effect of the jammer.