Comparative Analysis of Propagation Pathloss and Channel Power of VHF and UHF Wireless Signals in Urban Environment

International Journal of Research and Innovation in Social Science (IJRIAS) | Volume IV, Issue VII, July 2019 | ISSN 2454–6194

Comparative Analysis of Propagation Pathloss and Channel Power of VHF and UHF Wireless Signals in Urban Environment

Aremu Olaosebikan Akanni^1*, Odepidan Kolawole Omeiza²., Makinde Oluniyi Samuel³, Azeez Waheed Adebayo^4
1,2,3,4Physics Department, The Polytechnic, Ibadan. P.M.B 22, UI Post Office, Ibadan, Nigeria

Abstract: The paths loss propagation model is an important tool in wireless network planning but inaccurate models normally leads to networks co-channels interference and a waste of power. Hence, it is important to investigate the radio path loss and the channel power behaviour for working out radio and LTE technology. In this work, a comparative analysis of path loss prediction models with measured data and channel power is presented. Three different propagation path loss models (Free space, Okumura and Egli) have been analyzed and compared with measured data. The experimental campaign took place in Ogbomoso, south western, Nigeria (8.1227oN, 4.2436oE) and the measured data were obtained at two frequency bands; 150 MHz (VHF) and 900 MHz (UHF). The results and statistical analysis revealed that, for the two frequency bands considered, Okumura model is in good agreement with measured path loss having root mean square errors (RMSE) 3.98 and 5.86 for VHF and UHF band respectively while free space and Egli overestimated the measured path loss. The RMSE values obtained are within the acceptable minimum standard limit, 6 dB for good radio signal propagation. It was also noted that, the channel power decreases with increase in distance. The mean channel power and the pathloss exponent obtained for 150 MHz are -72 dBm and 2.189 respectively while for 900 MHz it was -85 dBm and 2.650 respectively. These values will assist the communication engineers for proper planning in this environment.

Key words: Channel power, Path loss, radio signal, VHF, UHF.

I. INTRODUCTION

Understanding the effects of varying conditions on radio propagation has many practical applications; from choosing frequencies for international shortwave broadcasters, to designing reliable mobile telephone systems, to radio navigation, to operation of radar systems [1] [2]. Precise estimation of radio propagation path loss is a major factor for the good design of mobile and radio systems. In terrestrial cellular radio systems, radio signals generally propagate by means of any or a combination of these three basic propagation mechanism: reflection, scattering and diffraction. Path loss is the difference (in dB) between the effective transmitted power and the received power and may or may not include the effects of the antenna gains but it is influenced by terrain contours, environments (urban, sub-urban and rural), vegetation and foliage.

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