Wireless Propagation in the Near-Ground Forest Environment

Abstract

This thesis presents propagation measurements for a peer-to-peer wireless network for near-ground sensor networks, in the forest environment. Measurements were performed for Deciduous, Coniferous and Mixed forest species in the winter and summer seasons, as well as measuring the propagation characteristics of a cutline. Results indicate dual path-loss behaviour, typical of Fresnel zone obstructions. The small scale Rician K-factor was found to increase in the summer months, due to the presence of foliage. The cut line environment exhibited an oscillatory decay, suggesting the presence of a strong ground reflection. Antenna correlation was found to be dependent on the topology of the forest, and frequency diversity was limited due to a lack of scattering objects. The results were used to simulate the physical layer performance of a fixed wireless link, using SISO, SIMO and frequency hopping diversity schemes.