3g gps tracker needs to insert a SIM card into the tracker to achieve positioning and tracking of vehicles. Why? First of all, let's briefly understand the positioning and tracking principle of the 3g gps tracker. In fact, the working principle of the 3g gps tracker is relatively simple, that is, the locator receives the data sent by GPS satellites, and then transmits these data to the ground server for analysis, and we can view the vehicles installed in the 3g gps tracker in real time through mobile phones or computers the location. 3g gps tracker needs to transmit the data received by the device to the server in the process of positioning and tracking. Only after this step can we see the location, and how to realize the transmission of these data, then we need to use SIM stuck. We all know that the SIM card has the function of communication. We usually call it traffic, which is GPRS. If the sim card is not inserted in the 3g gps tracker, the positioning data cannot be transmitted to the server, and we cannot see the location of the vehicle on the map. If you are more concerned about the 3g gps tracker, you may have heard of the card-free 3g gps tracker, so how do these devices transmit data? In fact, these so-called card-free 3g gps trackers do not mean that SIM cards should not be installed, but these devices directly paste the SIM card chip on the PCBA board (that is, the main board) during the production process, so they are declared to be Card free! Having said so much, you should understand why the 3g gps tracker needs to install a SIM card.

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