Análise de propagação de rádiofrequência na banda de 900 MHz

Abstract

The process of implementing wireless communication networks assumes that a detailed survey of the attenuation factors are carried out for the channel in use, so that the best efficiency in communication between its points can be achieved. To determine the characteristics of a channel, several propagation models exist, which can be large or small, theoretical or empirical, in order to consider as many attenuating factors as possible, such as the Okumura model, COST 231 and log-distance. In the present work, the large-scale log-distance propagation model will be explored and then the behavior of the small-scale channel will be analyzed through the Nakagami-𝑚 propagation model. Using the large-scale log-distance propagation model, a propagation loss coefficient equal to 1.841 was calculated, for the free space condition and with the antennas under line of sight, and for the condition without line of sight considering effects of shading, the value of the path loss coefficient was 3.778. Using the small-scale propagation model Nakagami-𝑚, it was possible to determine the Nakagami parameter through two different methods, obtaining values of 1.49 and 1.57. To carry out the tests, development kits were used with transceiver modules produced by the company Texas Instruments together with the SmartRF Studio 7® wireless network configuration software also from the company Texas Instruments.