现有矿井人员定位方法定位误差大,难以满足煤矿事故救援、运输和机电事故防治等需求。为提高矿井人员定位精度,提出了异步测时矿井人员精确定位方法:在井下巷道中间隔一定距离安装定位分站,保证相邻分站可相互无线通信,定位卡可与两个邻近分站同时进行通信。任一定位发起分站向通信范围内的定位卡和相邻分站发送测距信号,相邻分站收到测距信号后也向定位卡发送测距信号,定位卡分别向定位发起分站和相邻分站回复应答信号。定位发起分站收到定位卡回复的应答信号后,计算收发测距信号时间。相邻分站收到定位卡回复的应答信号后,计算收发测距信号时间,并将其发送给定位发起分站。定位发起分站根据本分站和相邻分站收发测距信号时间、本分站与相邻分站间距和信号传输速度,计算出定位卡距本分站和相邻分站距离。异步测时法测距仅与分站收发测距信号时间有关,与信号强度无关,定位精度不受信号发送功率、接收灵敏度和信号传输衰减影响。异步测时法与定位卡时钟无关,大大降低了定位卡复杂度和成本,同时也不需要定位分站之间同步,降低了定位分站复杂度和成本。仿真实验表明,在时钟频率偏移相同等实验条件下,TWR和SDS-TWR等其他矿井人员精确定位方法的定位误差是异步测时法定位误差2倍以上。

The existing underground coal mine personnel positioning methods always have a large positioning error,and it is difficult to meet the needs of coal mine accident rescue,transportation,and electromechanical accident prevention and control. To improve the accuracy of underground coal mine personnel positioning,an underground coal mine accu- rate personnel positioning method based on asynchronous time-measuring was proposed:some locating substations are installed at certain distance in the underground roadway to ensure that the two neighboring locating substations can communicate with each other wirelessly and the positioning card can communicate with two neighboring locating sub- stations at the same time. Any one initial locating substation sends a ranging signal to the positioning card and the neighboring locating substation in the communication range. The neighboring locating substation receives the ranging signal and at the same time it sends a ranging signal to the positioning card. The positioning card replies response sig- nals to the initial locating substation and the neighboring locating substation separately. After receiving the response signal replied from the positioning card,the initial locating substation calculates the time between sending and receiv- ing the ranging signal. After receiving the response signal replied from the positioning card,the neighboring substation calculates the time between sending and receiving the ranging signal,and sends the time to the initial locating substa- tion. According to the time between sending and receiving the ranging signal calculated by the initial locating substa- tion and the neighboring substation separately,and the distance and signal transmission speed between the initial loca- ting substation and the neighboring substation,the initial locating substation calculates the distance between the posi- tioning card and the initial locating substation and the distance between the positioning card and the neighboring sub- station. Measuring distance using the underground coal mine accurate personnel positioning method based on asyn- chronous time-measuring is only related to the time of sending and receiving ranging signal from the substation and not related to the signal strength. The accuracy of positioning is not affected by the signal transmission power,receiving sensitivity and signal transmission attenuation. The underground coal mine accurate personnel positioning method based on asynchronous time-measuring is not related to the clock of the positioning card,which greatly reduces the complexi- ty and cost of positioning cards,eliminates the need for synchronization between locating substations,and reduces the complexity and cost of locating substations. The main performance indicators of the underground coal mine accurate personnel positioning method based on asynchronous time-measuring are superior to other underground coal mine posi- tioning methods. Simulation experiments show that under the same experimental conditions such as the same clock fre- quency offset,the positioning error of other underground coal mine accurate personnel positioning methods such as TWR and SDS-TWR is more than twice of the positioning error of the underground coal mine accurate personnel posi- tioning method based on asynchronous time-measuring.