Research And Improvement Of Wireless Meter Reading Method Based On LoRaWAN

With the development of smart city construction,the requirements for IoT technology are increasingly high,which puts forward higher requirements for power consumption and communication distance of network equipment.Long Range technology was born at the right moment.Due to the good application prospect of LoRa technology,many countries have been competing to carry out research on it.Starting from LoRa's Media Access Control layer protocol LoRaWAN,this paper studies and improves the wireless meter reading system based on LoRaWAN's network architecture defined by LoRaWAN protocol.The specific research contents are as follows:First,this thesis establishes a series of models that cover various aspects of a LoRa network.It includes link measurement model and link performance model,among which link measurement model includes path loss,building penetration loss and shadow loss,link performance model includes receiver sensitivity,interference model and gateway model,etc.Then,a new Network Simulator 3 module is introduced to simulate a LoRa-based IoT network in a typical urban scenario,including models of physical layer,link layer,MAC layer,gateway and network server to simulate the Internet of things network.Finally,the performance of the LoRa system is evaluated and analyzed.Simulation results show that LoRaWAN network has higher throughput.In addition,in a network with about 15,000 terminal devices,the success rate of meter reading is over 95%,which proves that LoRaWAN network has good performance.Second,in order to reduce the power consumption of the meter reading system,the hardware and software are optimized respectively.Firstly,low-power devices are designed and selected to ensure low power consumption at the hardware level.Secondly,the software flow of the meter reading system is optimized to maximize the dormancy time of the terminal nodes,thereby reducing the overall powerconsumption of the system and extending the service life of the system.The test results show that the average operating current of the terminal node is about 0.15 mA.If the battery of 20000 mAh is used,the equipment can ideally run for nearly 10 years and meet the application requirements.