Modeling of Wi-Fi signal propagation under tree canopy in a college campus

E-governance and real time monitoring of regular activities and devices connected in a network using Wi-Fi are becoming part of any campus infrastructure. Hence, optimizing any Wi-Fi campus area network by characterizing the propagation channels becomes necessary. Even though accurate evaluation of onsite performance is possible with direct measurements, it requires considerable amount of time and efforts. Therefore, modeling the electromagnetic wave propagation using a computer tool and characterizing the wireless channel from the building plans and material properties would be a good solution. This paper considers an approach for developing such a simulation tool for propagation prediction of electromagnetic waves in a Wi-Fi network of 2.4 GHz and to predict the path loss characteristics. Assuming that the scattering objects are much larger than their wavelength, the electromagnetic waves are modeled as rays. In addition, as most of the college campuses are covered with trees in India, the signal variation due to tree canopy has also been studied.

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