Key technology of an identification card for mobile phone positioning

In order to solve the problem that most of the existing mine-used smart phones only have the functions of voice calls, video photos, data transmission and so on, and do not have the functions of precise positioning, position coordinate display, message linkage, an identification card based on UWB technology is designed. The identification card realizes two-way data communication with the smart phone through low-power bluetooth. The identification card completes the precise positioning with the UWB station using the TOF positioning algorithm, obtains the position coordinate information, sends it to the smart phone through the low-power bluetooth (BLE), and displays the current specific position coordinates through the mine GIS roadway map on the smart phone APP. This paper introduces the key technologies of the identification card in detail, including mine roadway position coordinate model, precise positioning algorithm, message linkage reliable transmission mechanism, low power consumption sleep technology. The test results show that the positioning accuracy of the identification card is less than ± 0.3 meters, the positioning distance can reach 400 meters, the message linkage transmission delay is less than 2 seconds, the position coordinate display is accurate, the sleep current of the positioning module is less than 25 uA, and the average current meets the low power consumption design requirements.