Abstract: In view of problems of single function and low positioning accuracy existed in underground personnel positioning system, an intrinsic safety and multi-functional wireless information transmission platform based on 802.11n was designed. The platform is based on 802.11n transmission protocol and uses signal strength measurement module, which not only can realize high speed transmission of data, voice and video, but also can realize real-time positioning of underground personnel through WiFi signal. The actual test results show that wireless transmission rate of the platform reaches 120 Mbit/s, the signal coverage is 500 m, real-time positioning accuracy is 9.68 m, satisfy requirements of coal mine safety information transmission.