Application of Weissberger Model for Characterizing the Propagation Loss in a Gliricidia sepium Arboretum

Simeon Ozuomba,Emmanuel Nsese Udoiwod,Enyenihi Henry Johnson

doi:10.13189/ujcn.2018.060202

Abstract

In this paper, the Weissberger and the Early ITU propagation loss models were used to characterize the propagation loss for a 3G cellular network. Particularly, the 3G network operates at a frequency of 1800 GHz and the case study site is a Gliricidia sepium arboretum which is a Gliricidia sepium Tree Park planted and maintained mainly for scientific study in the annex campus of University of Uyo. Cellmapper app installed on Tecno i5 mobile phone was used to capture the received signal strength; the latitude and longitude of the data capture points, as well as the time and the key cellular network base station data. The relevant mathematical models used to process the measured data and for tuning the Weissberger and the Early ITU propagation loss models were also presented. The Weissberger and the Early ITU propagation loss models were tuned using foliage depth tuning constant. The tuned models prediction performances were evaluated using cross-validation dataset. With the training dataset, the un-tuned Weissberger model had a root mean square (RMSE) value of 21.098 dB while the tuned Weissberger model had a RMSE of 3.375 dB. Similarly, with the training dataset, the un-tuned Early ITU model had a RMSE of 21.970dB while the tuned Early ITU model had a RMSE of 4.019dB. The tuned Weissberger model with the lowest RMSE was adopted for the prediction of the propagation loss in the case study Gliricidia sepium arboretum. Furthermore, the Weissberger model was evaluated using the cross-validation dataset and it had RMSE of 4.507dB.

Highlights

When wireless signal propagates through the atmosphere without any obstruction, it suffers the spreading or free space propagation loss 4,5,6]
ITU propagation loss models while the second dataset, referred to as the validation dataset was used for cross-validation of the tuned propagation loss models
The prediction performances in terms of root mean square (RMSE) are shown in Table 1 for the Weissberger and the Early ITU propagation loss models

Summary

Introduction

When wireless signal propagates through the atmosphere without any obstruction, it suffers the spreading or free space propagation loss 4,5,6]. Determination of the received signal strength at any location within the arboretum can be done using some foliage propagation loss models [12, 13, 14]. The Weissberger and the Early ITU foliage propagation loss models are used to characterize the propagation loss within an arboretum that consists of mainly Gliricidia sepium trees [15, 16, 17, 18, 19]. In this paper, the focus is to conduct empirical field measurements of the received signal strength within the gliricidia sepium arboretum and use the field measured data to tune the Weissberger and the Early ITU foliage propagation loss models so that they will provide more accurate estimation of the expected foliage propagation loss that can be experienced by the 1800 GHz wireless signal

The Case Study Site and Data Collection

The Weissberger–Based Propagation Loss for an Area Covered with Vegetation

The Early Itu –Based Propagation Loss for an Area Covered with Vegetation

Results and Discussion

Conclusions