Hydraulic support condition monitoring system based on LoRaWA

In view of unstable communication and poor anti-interference ability of the existing hydraulic support condition monitoring system, a hydraulic support condition monitoring system based on LoRaWAN was designed. Sensor nodes use rate adaptive technology to periodically upload data, and can actively upload data in case of abnormal conditions, and use sequential polling to reduce transmission error rate; gateways simultaneously transmit uplink and downlink commands through independent uplink and downlink channels, which reduces collision probability of uplink and downlink commands, and improves data forwarding efficiency. In order to ensure signal coverage of fully mechanized mining face, a gateway is installed at the corner of the roadway, and the LoRa wireless signal of the fully mechanized mining face is forwarded to application platform through a jump transmission. Experimental results show that the system can effectively cover the entire fully mechanized mining face and realize condition monitoring of hydraulic support,when communication distance is 150 m, the data transmission packet loss rate is 0, and the data transmission time of a single sensor node is about 0.29 s,the system acquisition cycle is within 200 s, which meets application requirements.