Personnel position method in underground coal mine

The characteristics of the underground coal mine personnel positioning are analyzed and summarized: the coverage is much larger than the indoor environment; the transmission of the positioning signal should be not line of sight; the attenuation of electromagnetic wave is serious; the attenuation of wireless transmission is affected by the gallery branching, bending, inclination, the area and shape of cross-sectional, the medium of surrounding rock, the roughness of gallery surface, support, longitudinal conductors, transverse conductors, equipment and etc; theelectrical equipment must be explosion-proof; the underground coal mine environment is harsh because of dust, moisture, water and etc.It is proposed that the radio transmission is suitable for the underground coal mine personnel positioning; while ultrasonic, laser, and infrared transmissions are not suitable for underground coal mine personnel positioning.And, it is proposed that the positioning method based on received signal strength indication(RSSI) is not suitable for underground coal mine accurate personnel positioning; the positioning method based on angle of arrival(AOA) measurement is not suitable for underground coal mine accurate personnel positioning; the positioning method based on time of arrival(TOA) and the positioning method based on time difference of arrival(TDOA) within similar signal source are suitable for underground coal mine accurate personnel positioning, and the positioning system based on time difference of arrival(TDOA) within similar signal source costs less than the positioning method based on time of arrival(TOA); the positioning method based on time difference of arrival(TDOA) within different types of signal source is not suitable for underground coal mine accurate personnel positioning.