Figure 9 depicts the soil water content present at
the node 7 location. Peaks at day 7 and 10 indicate
they were rainy days, followed by a 12 days period
almost without rain.
Other sensor data shows, for example, solar
radiation, in Watts per square meter, present at each
node location. (Figure 10).
Figure 10: Solar radiation (W/m
2
) Node 7.
7 CONCLUSIONS
A complete measurement campaign was developed
to model the propagation channel of the links among
elements of a wireless sensor network. This
propagation model has been used for planning an
actual installation in a vineyard close to Ribadavia,
in Galicia. The Eko technology, from Memsic, has
been selected for this deployment. Up to 6 eko nodes
were set up into the vineyard, to cover an area of
approximately 6 km2.
Four different sensors have been plugged into
each eko node, to collect different ambient and soil
parameters, like humidity, temperature, solar
radiation, water content, etc.
With the aid of these sensor data, vineyard
owners could, for instance, predict the appearance of
a plague in their terrains or optimize the terrain
irrigation. Furthermore, the time between sulphate
applications in the vineyard could be extended. This
last improvement may allow farmers to save a lot of
money in material and labour, and reduce the
amount of chemical products applied to the
vineyard.
ACKNOWLEDGEMENTS
This work has been supported by the Autonomic
Government of Galicia (Xunta de Galicia), Spain,
under Project PGIDIT 08MRU045322PR and by
European Union under project “RFID from Farm to
Fork” (CIP-Pilot actions grant number 250444).
The authors would also like to acknowledge
Manuel Leites, who helped during the deployment.
REFERENCES
Egan, D., April-May 2005. “The emergence of ZigBee in
Building Automation and Industrial Controls”,
Computing & Control Engineering Journal, vol. 16,
no. 2, pp.14-19.
Timmons, N. F. and Scanlon W. G., 2004. “Analysis of
the performance of IEEE 802.15.4 for medical sensor
body area networking," First Annual IEEE
Communications Society Conference on Sensor and
Ad Hoc Communications and Networks, 2004. IEEE
SECON 2004, pp.16-24.
LaGrone, A., Chapman, C., 1961. "Some propagation
characteristics of high UHF signals in the immediate
vicinity of trees," Transactions on Antennas and
Propagation, IRE, vol.9, no.5, pp.487-491.
Richter, J., Caldeirinha, R. F. S., Al-Nuaimi, M.O.,
Seville, A., Rogers, N. C., Savage, N., 2005. "A
generic narrowband model for radiowave propagation
through vegetation," Vehicular Technology
Conference, vol.1, pp. 39- 43
Int. Telecommun. Union (ITU-R), 2007, “Attenuation in
Vegetation,” ITU-R Recomm. 833-6.
Hashemi, H., 2008. “Propagation Channel Modeling for
Ad hoc Networks”, European Microwave Week.
Nükhet S. and Haldun A., 2009. “The Importance of
Using Wireless Sensor Networks for Forest Fire
Sensing and Detection in Turkey”; 5th IATS’09,
Karabuk, Turkey.
Hefeeda, M. and Bagheri, M., 2007."Wireless Sensor
Networks for Early Detection of Forest Fires," IEEE
International Conference on Mobile Adhoc and Sensor
Systems, 2007. MASS 2007, pp.1-6.
Cuinas, I., Gay-Fernandez, J. A., Alejos, A., Sanchez,
Manuel, 2010.”A comparison of radioelectric
propagation in mature forests at wireless network
frequency bands,” European Conference on Antennas
and Propagation (EuCAP), 2010, pp.1-5.
Gay-Fernandez, J. A., Garcia Sanchez, M., Cuiñas, I.,
Alejos, A. V., Sánchez, J. G. and Miranda-Sierra, J.
L., 2010, “Propagation Analysis and Deployment of a
Wireless Sensor Network in a Forest”, Progress In
Electromagnetics Research, PIER 106, pp. 121-145.
Crossbow Technology, Inc, 2009, “Eko PRO Series Users
Manual, Rev. C”.
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