Evaluating effect of foliage on link reliability of wireless signal

Applications of low cost wireless sensor nodes in precision agriculture are being gradually adopted by commercial agricultural cooperatives as part of the continuing industrialisation of commercial agriculture. Current applications require extensive testing and experimentation to ensure reliable message transmission, because the transmitted wireless signal is scattered by the surrounding foliage. Network topology and node density is not optimized. In this paper, experiments to determine the effect of surrounding vegetation on the wireless signal in terms of link reliability, and signal strength for three different types of agricultural crops, namely, ground foliage, medium height and density vegetation, and very dense types of foliage is analyzed and discussed. The objective is to demonstrate that current radio propagation foliage loss models are not optimised for use in precision agriculture.