@article{article_1892489, title={Comparison of Distance and Physical Obstacle Effects on Real-Time Data Transmission Using Esp32 and LoRa}, journal={Journal of Science, Technology and Engineering Research}, year={2026}, DOI={10.53525/jster.1892489}, url={https://izlik.org/JA78GT98ES}, author={Kolcu, Cafer Ayhan and Doruk, Reşat Özgür}, keywords={ESP32, LoRa, RSSI, İç mekân kablosuz haberleşme, Engel zayıflatması, Biyomedikal veri iletimi}, abstract={Reliable indoor real-time data transmission is essential for biomedical and IoT monitoring applications; however, wireless link quality can vary significantly with distance and the presence of common building materials. This study presents an experimental comparison of ESP32-based Wi-Fi (2.4 GHz) and LoRa RA-02 communication (433 MHz) under indoor conditions, with a focus on the effects of propagation distance and physical obstacles on link performance. In addition to communication analysis, the study also demonstrates the acquisition of analog biomedical signals and environmental data, their wireless transmission, and real-time visualization at the receiver side. To ensure a consistent comparison, both technologies were tested under identical indoor procedures using received signal strength indicator (RSSI) as the primary evaluation metric. Four experimental scenarios were considered, including short-range reference measurement, straight-corridor distance tests, non-line-of-sight L-shaped corridor measurements, and obstacle-based attenuation tests involving commonly encountered construction materials. The experimental results show that ESP32-based Wi-Fi provides satisfactory performance in short-range and relatively unobstructed indoor environments, where higher data exchange capability is advantageous. However, its signal strength decreases more noticeably as transmission distance increases and when obstacles are introduced. In contrast, LoRa exhibits greater resistance to attenuation caused by both distance and indoor obstacles, maintaining more stable RSSI behavior across medium- and longer-range scenarios. Overall, the study provides a practical indoor performance evaluation of two widely used wireless communication technologies and demonstrates that protocol selection should not depend solely on nominal communication range, but also on obstacle sensitivity and application-specific monitoring requirements. The findings offer useful guidance for the design of indoor biomedical and IoT monitoring systems operating in realistic built environments.}, number={1}