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Some agents and dealers who undertake construction or plan to plan mobile phone signal shielding systems often need to conduct project site surveys at the beginning of the project. If they do not have sufficient experience in such similar projects, they will consult our manufacturers. , the first question to be concerned about is: what equipment is needed for the construction survey of the mobile phone signal shielding system project?

The first is the preparatory work before the project survey. The preparation items in this part include but are not limited to: the main requirements of the project demander, the main areas targeted by the mobile phone signal shielding system project, and the building plan, structure diagram or room of the project demander distribution map, etc. In addition to these, it is best to know or master the preparation information in advance, including: the distribution location of base stations around the project site, the distance of base stations, and so on.

Next is the equipment that needs to be prepared for the construction survey of the mobile phone signal shielding system project. If there is a manufacturer who can assist in the site survey, then as an essential tool for signal detection and analysis: a wireless signal frequency band analyzer is definitely essential. If there is a professional engineering mobile phone with detection tools, it will be even better. If the above two points cannot be achieved, the minimum preparation requirements for the detection equipment are: prepare smart phones of several standards, and install signal detection software on the mobile phone in advance. For example, the most common mobile phone signal detection software is "Cellular- Z". The data detected and recorded on the spot by the mobile phone signal detection software can still play a certain auxiliary role in the design of the mobile phone signal shielding system project.

For the project site survey of the mobile phone signal shielding system, in addition to the equipment or mobile phone software that needs to be prepared for testing, if conditions permit, it is best to prepare at least one or two mobile phone signal jammers, so that during the site survey process, preliminary Select several test points, turn on the shielding equipment to work, check and record the actual shielding range of the cell phone blocker at these positions, and use this as reference data to provide practical points for future mobile phone signal shielding system projects Bit reference standard.

The last thing to be reminded is that if you bring a mobile phone signal shield to the field for actual measurement, it is best to prepare a power supply terminal board with sufficient length in advance, so as to avoid finding that the power supply line for the shielding device is too short during the on-site test, resulting in equipment installation. If the height is not enough or the position is not ideal, the reference value in line with the actual shielding effect will be lost.

When the mobile phone is far away from the base station, or in the wireless shadow area, the base station can order the mobile phone to emit higher power, up to 33dBm (GSM900), to overcome the signal loss caused by long-distance transmission or building occlusion. If the mobile phone is very close to the base station and there is no obstruction, the base station can order the mobile phone to emit less power.

As shown in the figure below, when the mobile phone is close to the base station antenna, the received signal is strong (-65dBm), and the transmission is small (8dBm); when the mobile phone is far away from the base station antenna, the received signal is weak (-93dBm). Therefore, the transmit power will be larger (20dBm=100mW=0.1W).