Propagation of Radio Waves in Wine Cellars

Monitoring, control and management of wine production using sensors, IoT and machine learning methods is becoming more and more common. Wireless connection of sensors requires knowledge of losses due to electromagnetic (EM) wave propagation, and wine cellars represent a specific environment due to their architecture and wine vessels that hinder wave propagation. This paper presents the results of measuring EM wave losses in a basement with characteristics similar to wine cellars, and the measurement results are compared with the corresponding theoretical models. Measurements were performed for frequencies 860 MHz and 2.4 GHz, for LOS and NLOS conditions. It was found that at small distances from the transmitting antenna, losses increase according to the Free space model, and then the waveguide mechanism and multimode propagation begin to dominate. The tunnel model in this region gives a rough approximation of the losses. Furthermore, it was shown that in the NLOS region the losses can be modeled with the knife-edge diffraction loss model.