Propagation characteristics of 2.4GHz wireless channel in cornfields

Researches on propagation characteristics of wireless channel in cropland environments will lay the foundation for network deployments of wireless sensor network (WSN) for agricultural information acquirement. In this study, cropland with corn in maturity stage was selected as the representative of worst-case scenarios for radio propagation within cropland, and the propagation mechanisms and the impact factors on the propagation characteristics of wireless channel in this environment were analyzed. In addition, the power strength Radio Signal Strength Indicator (RSSI) and Packet Loss Rate (PLR) were measured in cornfields, and the node´s coverage was further obtained. The experimental results were analyzed to provide the guidance and suggestion for the WSN deployments. In the engineering practice, the nodes shall be placed in open area such as wide walkways when it is possible in order to minimize propagation loss and increase the node´s coverage effectively. And the antenna height of 1.4m to 1.6m is a good option, which will be more economic and feasible. Furthermore, experimental results also verified that rainfall doesn´t have much effect on the propagation of 2.4GHz wireless signal. And although raising the transmitted power can increase the transmission range significantly, both the power usage of battery and the radio surveillance regulations have to be taken into account.