Evaluation Of Radiated Electromagnetic Immunity Of The IoT LoRa Protocol

Background: With the advancement of Industry 4.0, the automation of industrial processes has shifted from wired communication technologies to wireless networks, enabling greater flexibility, efficiency, and scalability. Technologies such as LoRaWAN and NB-IoT have been widely adopted due to their low energy consumption and long-range communication capabilities, which are essential for industrial applications. However, the increasing density of connected devices has introduced new challenges, particularly related to electromagnetic interference (EMI), which can degrade network performance, cause packet loss, and delay communication. EMI, caused by various sources such as electronic devices and natural phenomena, is a critical issue in industrial environments. EMI simulations and analyses allow for network parameter adjustments and the implementation of mitigation techniques, ensuring robust communications. This study's primary objective is to test the radiated electromagnetic immunity of the LoRa protocol, assessing its ability to operate in environments subject to electromagnetic interference. The research emphasizes the importance of understanding EMI impacts to preserve data accuracy, improve communication performance, and ensure regulatory compliance, fostering a safe, reliable, and efficient industrial environment. Materials and Methods: The study evaluates the radiated electromagnetic immunity of Heltec LoRa ESP32 V2 boards, essential for IoT applications, in compliance with the IEC 61000-4-3 standard, which establishes methods for testing immunity to high-frequency electromagnetic fields. The boards were tested in an anechoic chamber to analyze the impact of radiated fields on LoRa communication. During the tests, conducted at frequencies from 80 MHz to 6 GHz and with a field intensity of 10 V/m, a transmitting board continuously sent LoRa packets while the receiving board recorded RSSI values and packet reception rates. The results demonstrated the sensitivity of the LoRa protocol to electromagnetic interference, evidenced by RSSI variations and packet losses under certain conditions. The tests highlighted the importance of robust configurations to maintain data integrity and device functionality in challenging industrial environments. The study provides valuable insights for improving electromagnetic compatibility in Industry 4.0 and IoT applications, meeting the criteria established by the IEC 61000-4-3 standard. Results: The study identified critical communication disruptions in the LoRa system at specific frequencies (305 MHz and 730 MHz) under radiated electromagnetic fields with a power of 1.5 dBm, characterized by packet loss and performance degradation. At 3 dBm, total communication failure occurred, attributed to internal resonances in the RF components and insufficient shielding or filtering of the modules. The interference likely overlapped with harmonics of the LoRa signal, reducing its ability to distinguish useful signals from noise. These findings highlight the system's vulnerability to specific EMI conditions, emphasizing the need for improved filtering, shielding, and protocol adjustments to enhance robustness in industrial environments. Conclusion: The study finds LoRa unstable at 305 MHz and 705 MHz with 1.5 dBm, causing packet loss and potential communication failure, highlighting the need for mitigation in high-interference environments.