<![CDATA[The shadow of diffraction, which account for the growth of trees based on wireless sensors and automatic acquisition of environmental information, were presented to meet the requirements for a wireless sensor network in a forest. there’s a necessity to avoid the dead zone of signal diffraction when laying wireless sensor in the forest, the integration of SBR and UTD is applied to study the impact of 2.4GHz radio-frequency signal on the path loss characteristics in the forest. Shadow fading is studied by considering random variations of trees height and position. Path loss to subscribers located in a forest are found using refraction and diffraction concepts. This paper achieved the ray location from the receive pint to field point by using back-ray tracing method and computed the response electric field relative to each ray by using UTD. This article presents an overview of popular prediction models and describes electric field algorithms that are based on the authors' experience, to improve their accuracy. Take the poplar planted forest for instance. The measured value and simulated value were compared, finding good consistency between them, which indicates that SBR and UTD can effectively predict the path loss characteristics in the forest. DOI: http://dx.doi.org/10.11591/telkomnika.v11i7.2833]]>
