Analysis of Sub-Giga Band Propagation for Maritime Low Power Wide Area Application

In this paper, we clarify the characteristics of sub-Giga band radio wave propagation at sea for the application of LPWA (Low Power Wide Area) radio in aquaculture. A particular feature of this scenario is high-sensitivity low power communication system (RSSI: received signal strength indicator-142 dBm typical, transmitter power 20 mW at 920 MHz) over a 22 km distance. Additionally, it is determined that the island size (width on a propagation line) has a great influence on the diffraction phenomenon, which can be expressed by a multiple knife-edge model.