In the last decades, the use of mobile telephone have become of great importance because of the growing on the use, this become its study very relevant to solve the problems brought from the increase of demand. In this Thesis, it is developed a model for the study of electromagnetic waves propagation loss, using the formalism of parabolic equation applied to mobile communication in an semi-confined and mixed environment. Crank-Nicolson’s finite differences schema is applied to calculate the parabolic equation (PE) solution. The fifteen degrees in the direction paraxial propagation and the complex refractive index were considered respectively. In other to validate the method a campaign of measurement was carried out in different cities in Para state. In Belém,at Braz de Aguiar Avenue, and in Benfica and Marituba, the frequency used was 900 MHz, and in Barcarena and Abaetetuba the frequency was 1,8 GHz. The results were validated by comparison between the simulations via Parabolic Equations and the measurements obtained at those environments. Besides that, the proposed model was compared with others models in the literature, and presented a good performance. An extension to the model was the consideration for angles in the paraxial direction up to 90º. In this case, was used the Fourier transform to solve the parabolic equation. The obtained results presented a good performance with improvement in the results for big angles up to 90°. The computational processing time using the formalism of EP is rather small.
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