Research On Key Technologies Of Underground Integrated Energy Monitoring System Based On LoRa Communication

In recent years,with the acceleration of underground space development and the improvement of energy utilization efficiency,underground integrated energy monitoring systems have become more and more important.At the same time,the Internet of Things has developed rapidly,which can meet the needs of more efficient and convenient monitoring.This paper analyzes the needs of application scenarios,and designs an underground integrated energy monitoring system based on LoRa communication for the problems of long underground space distribution,multiple monitoring parameters,multiple working equipment,and blind areas of public network signals.Firstly,the hardware circuit of LoRa communication device based on STM32 is designed.STM32F103C8T6 chip is used as the main control module,SX1278 chip is used as the LoRa radio frequency module,CH340 and MAX485 are used to realize the USB to TTL and 485 to TTL respectively,and AMS1117 is used to realize the voltage stability of the circuit.The software program flow chart,some key codes and hardware circuit schematic diagram of LoRa equipment are described.Secondly,in view of the large number of devices and the large number of LoRa communication nodes in this system,which leads to the easy occurrence of communication data collision,and considering the large increase in the number of time slots caused by the increase in the number of end devices and the poor stability of the system,a new LoRa WAN anti-collision algorithm is designed.By fan-shaped equal division equipment group,in order to achieve a single set of reduce the number of nodes and reduces the probability of the collision,and the unsuccessful communication nodes are estimated and the best number of the slot to adjust to improve the efficiency of the use of time slot.Through simulation comparison,under the scenarios of node number is as high as 2000,compared with LoRa WAN protocol based on DFSA,the proposed algorithm is 27.52% higher in PDR,20.33% higher in throughput rate and 17626 fewer in slot number.PDR is 51.27% higher than standard LoRa WAN protocol,and throughput is 26.93% higher.The effectiveness of the algorithm is proved by three comparisons.Finally,the software program of the monitoring system is designed,and the data is tested in the face of practical application.Specifically,it includes the design and implementation of the configuration interface of the monitoring system,the design and implementation of the configuration interface of the remote monitoring of mobile phones,the software connection of LoRa device,realize the communication between LoRa equipment,and in the experiments in2 km distance still keep 3.5% packet loss rate,at the same time have the experiment data,achieved the communication requirements of this system for LoRa module,meets the requirements of the application of this system.In conclusion,based on signal blind area of underground space and LoRa equipment more packet collision problems,from communication and collision algorithm to improve,and with industrial control software to realize the whole system monitoring platform,and experimental verification,the development of comprehensive energy monitoring system for underground has obvious significance.