RT Dissertation/Thesis
T1 Peer to peer propagation in vegetation media
A1 Gay Fernandez, Jose Antonio
K1 1203.25 Diseño de Sistemas Sensores
K1 2202.09 Propagación de Ondas Electromagnéticas
AB The use of wireless networks have been evolving in the last 5 years to many outdoors environments, as for instance several rural and  forested situations, where, initially, they were not supposed to be used. These wireless networks usually work at two ISM frequency bands, 2.4 and 5.8 GHz, and even in a licensed frequency, such as 3.5 GHz. One of the main characteristics of the wireless networks is that both transmitter and receiver usually work at the same height, and this is normally low. This situation is typically identified as apeer to peer scenario, which seems to be quite different from the classical master-slave scenario, where the transmitter is in a  predominant position over the receiver. Literature contains several papers analyzing the propagation of radio signal throughvegetation, but they generally focused on the classical master-slave scenario, or the frequency band analyzed was very different and results appears to be not valid. Thus, the necessity of propagation models under peer to peer conditions to facilitate the installation of these wireless networks in these new outdoor environments is greater every day. Based on these arguments, this PhD Thesis focuses on the path-loss modeling and short-term variation analysis of the signal propagated in four different kind of forests, and two types of meadows. Measurements were performed under peer to peer conditions with an antenna height below 1.6 meters. In this PhD Thesis a complete mathematical model is presented for a system configuration that was not usually considered until now. This model not only includes the path-loss evolution with the distance between transmitter and receiver, but also defines how the short-term  variations are with the distance. Furthermore, these studies have been performed the three frequency bands previously presented.The obtained results were compared with existing models such as the one from the ITU-R, in order to justify the research performed in this area. Finally, three application examples of these measurement campaigns are presented, including the development of a WSN in a vineyard to predict plagues and diseases, the design and test of anelectronic cowbell for outdoor animal tracking, and the installation of a WSN in a forest for fire monitoring and environmental control.
YR 2013
FD 2013-07-23
LK http://hdl.handle.net/11093/206
UL http://hdl.handle.net/11093/206
LA eng
NO Xunta de Galicia
DS Investigo
RD 03-oct-2024