ABSTRACT
In order to propose a reasonable prediction for radioclimatic study, a reliable radio propagation data is required. This radio propagation data can be either primary or secondary. The secondary data can be estimated from a relevant primary data which include temperature, pressure and humidity or water vapour pressure, while secondary radioclimatic data includes refractivity (N), refractive index (n) and effective earth’s radius (k-factor). The main concern of this work is secondary data, of which the measurement were made at Nsukka 6o 45N latitude and 7o 30E longitude, South –Eastern Nigeria, using an automatic wireless weather station Vantage Pro2, positioned at the surface level installed at National Center for Basic Space Science (NCBSS) Nsukka. The measurements of the primary variables were made at time interval of 30 minutes daily from August 2013 to July 2014. The results obtained show seasonal variation of the temperature and relative humidity. This leads to the increase in the values of radio refractivity and refractive index. The result also, show that the k-factor values for those months were at the range of 1.555 – 1.653, which is above the global standard value 1.333. The effect of this result leads to major propagation condition known as super- refraction which affects radio waves and lead to signal interference over Nsukka.
TABLE OF CONTENTS
Title Page
Approval
Certification
Dedication
Acknowledgement
Abstract
Table of Contents
List of figure
List of Tables
CHAPTHER ONE: INTRODUCTION 1.1 Preamble 1
1.2 Layers of the Atmosphere 3
1.2.1 The Troposphere 3
1.2.2 Stratosphere 4
1.2.3 The Ionosphere 4
1.2.3.1 D Region 5
1.2.3.2 E Region 6
1.2.3.3 F Region 7
1.3 Problem Statement 8
1.4 Objectives 8
1.5 Scope of the Work 8
CHAPTHER TWO: LITERATURE REVIEW 2.1 Preamble 9
2.2 Basic Theory 11
2.2.1 Ground Wave or Surface Wave 12
2.2.2 Space Wave Propagation 13
2.2.3 Sky Wave Propagation 13
2.2.4 Tropospheric scatter Wave 14
2.3 Refraction of Waves 15
2.4 Diffraction (Fresnel Zone) 16
2.4.1 Diffraction Fading Application 17
2.4.2 Fade Depth Application 18
2.5 Electromagnetic wave Propagation 19
2.6 Signal Loss 21
CHAPTHER THREE: MATERIALS AND METHODS3.1 Method of Measurement 28
3.2 Calculation of the Radio Refractivity 29
3.3 Estimation of Refractive Index (n) 31
3.4 Calculation of Effective Earth’s Radius (k-factor) 33
CHAPTHER FOUR:
RESULTS 37
CHAPTHER FIVE: DISCUSSION 45
CHAPTHER SIX:
SUMMARY, CONCLUSION AND RECOMMENDATION
6.1 Summary 49
6.2 Conclusions 49
6.3 Recommendations 50
References 51
Appendices
