Department of Computation, Federal University of Pará, Belém, Pará, Brazil.
Department of Mathematics, Federal University of Pará, Belém, Pará, Brazil.
PLoS One. 2018 Mar 29;13(3):e0194511. doi: 10.1371/journal.pone.0194511. eCollection 2018.
The establishment and improvement of transmission systems rely on models that take into account, (among other factors), the geographical features of the region, as these can lead to signal degradation. This is particularly important in Brazil, where there is a great diversity of scenery and climates. This article proposes an outdoor empirical radio propagation model for Ultra High Frequency (UHF) band, that estimates received power values that can be applied to non-homogeneous paths and different climates, this last being of an innovative character for the UHF band. Different artificial intelligence techniques were chosen on a theoretical and computational basis and made it possible to introduce, organize and describe quantitative and qualitative data quickly and efficiently, and thus determine the received power in a wide range of settings and climates. The proposed model was applied to a city in the Amazon region with heterogeneous paths, wooded urban areas and fractions of freshwater among other factors. Measurement campaigns were conducted to obtain data signals from two digital TV stations in the metropolitan area of the city of Belém, in the State of Pará, to design, compare and validate the model. The results are consistent since the model shows a clear difference between the two seasons of the studied year and small RMS errors in all the cases studied.
传输系统的建立和完善依赖于考虑到(除其他因素外)该地区地理特征的模型,因为这些特征可能导致信号降级。在巴西,这一点尤为重要,因为巴西的地貌和气候种类繁多。本文提出了一种用于超高频 (UHF) 频段的户外经验无线电传播模型,该模型可以估算可应用于非均匀路径和不同气候的接收功率值,这对于 UHF 频段来说是一个创新特征。不同的人工智能技术在理论和计算基础上被选择,使得可以快速高效地引入、组织和描述定量和定性数据,从而在广泛的环境和气候条件下确定接收功率。所提出的模型应用于亚马逊地区的一个城市,该城市的路径具有异质性,城市区域有树木,还有淡水等。进行了测量活动,以从帕拉州贝伦市大都市区的两个数字电视站获取数据信号,以设计、比较和验证模型。结果是一致的,因为模型显示了研究年份两个季节之间的明显差异,并且在所有研究案例中均具有较小的 RMS 误差。