Abstract:Due to a large number of metal structures and electromechanical equipment in the plant area,the electromagnetic environment was complex, so the application effect of LPWAN was difficult to judge. This paper studied the ideal deployment mode of LPWAN nodes, and carried out communication test in a representative complex electromagnetic environment,and analyzed the data transmission of LoRa in short distance, medium distance and long distance of NB-IoT. The practical application and test results showed that the main factors affecting the packet loss of LPWAN communication were the shielding property of metal structure and the electromagnetic interference of electromechanical equipment, rather than the communication distance. In order to the apply LPWAN in the plant area with complex electromagnetic environment, measures such as polling reception and dispatch and antenna extension cord suit shielding net should be adopted. In addition, the LPWAN terminal of the sending end should be arranged as tall as possible to achieve reception and dispatch visual, so as to reduce electromagnetic interference.