7 
Submitted in partial fulfilment for the degree of Master of Engineering in 
Electronics & Telecommunications 
K.S.M. VISHAKHA TfeeSkS Coll 
University of Moratuwa 
77708 
August 2002 
77708 
11108 
The work presented in this dissertation has 
not been submitted for the fulfillment 
of any other degree 
Prof. I.J. Dayawansa 
Supervisor 
Acknowledgement 
Dr. (Mrs.) Dileeka Dias deserves many thanks for spending her invaluable time 
from her busy schedule to supervise this and also to suggest solutions for the 
problems which could otherwise lead to a total failure. 
I am deeply indebted to Prof. (Mrs.) Dayawansa in most of all for her kind 
guidance and encouragement to proceed with this project. 
My special thanks go to Telecommunication Regulatory Commission for 
providing me the opportunity and necessary equipment to carry out this project 
and also to my colleagues who helped me a lot in numerous ways . 
Quite number of people who helped in numerous ways are also acknowledged 
even though it's hard to mention individually. 
Last but not least, my deep gratitude is extended to my family and close friends 
for their encouragement and helps right throughout the time without that this 
won' t be a reality. 
Contents 
Abstract i 
List of Figures ii 
List of tables iii 
1 Introduction 1 
2 Propagation in Mobile Environment 3 
2.1 Introduction 3 
2 2 Propagation Models y 
2.2.1 Statistical Models 7 
2.2.2 Deterministic Models 12 
2.2.3 Power-Law Model 13 
2.2.3.1 Propagation Constant 13 
2.2.4 Calculation of Distance 14 
3. Overview of the Work Carried Out 15 
3.1 Objective and Procedure 15 
3.2 Measuring Equipment and Selection of technical parameters 15 
3.2.1 Measuring Equipment 15 
3.2.2 Selection of Measurement sites 17 
3.2.3 Technical Parameters 20 
3.3 Measurements and Observations 22 
4 Results and Analysis 23 
4.1 Calculations from the observations 23 
<0 4.1.1 Calculation of Distance 23 
4.1.2 Calculation of Propagation Constant 37 
4.2 Results from ITU-R P.529 Model 37 
4.3 Comparison of Propagation Constant and Field Strength with ITU-R model 39 
4.4 Discussion of Results 40 
5 Conclusion 42 
References 45 
Appendix 1 46 
Appendix 2 ^ 7 <x 50 
Abstract 
Propagation in land mobile services including cellular is affected in 
varying degrees by topography, vegetation, man made structures, ground 
constants, the troposphere and the ionosphere. Also propagation of 
energy is strongly influenced by several factors including the natural and 
artificial relief, propagation frequency, antenna heights and others. 
The mobile radio signal varies in time and with spatial displacement. 
Even in the static case where the transmitter and receiver are fixed, the 
channel can be dynamic, since scatterers and reflectors are likely to be in 
motion. Thus multipath arises from the fact that through reflection, 
diffraction and scattering radio waves can travel from a transmitter to a 
receiver by many paths. Hence a precise estimation of signal 
characteristics in this environment constitutes a hard task. 
The thesis describes exercises in the estimation of the characteristics of 
cellular mobile signals operating in 900 MHz band through the real 
measurements obtained in different environments in Sri Lanka and the 
results of these exercises. Even though similar researches have been 
conducted in places like Europe, North America and Japan to derive 
empirical formulae such as Okomura- Hata Model, ITU-R P.529, 
COST231, no study has been done as yet to check the suitability of these 
models to the Sri Lankan environment. 
List of Figures 
1. Prediction Curve for Okomura-Hata Model 2.1 
2. ITU - R Curve 2.2 
3. Configuration of test Equipment 3.1 
4. Map of Borella 3.2 
5. Map of Kurunegala 3.3 
6. Map of Kottawa 3.4 
7. Graph of Field Strength Vs Distance for Borella Tx in Orugodawatta 4.1 
Direction 
8. Graph of Field Strength Vs Distance for Borella Tx in Narahenpita 4.2 
Direction 
9. Graph of Field Strength Vs Distance for Borella Tx in Rajagiriya 4.3 
Direction 
10. Graph of Field Strength Vs Distance for Kottawa Tx. 4.4 
11. Graph of Field Strength Vs Distance for Kurunegala Tx in 4.5 
Colombo Road Direction 
12. Graph of Field Strength Vs Distance for Kurunegala Tx. in 4.6 
Dambulla Road Direction 
13. Graph of Field Strength Vs Distance for Kurunegala Tx in 4.7 
Kandy Road Direction 
14. Graph of Field Strength Vs Distance for Kurunegala Tx in 4.8 
Negombo Road Direction 
15. Graph of Field Strength Vs Distance for Kurunegala Tx in 4.9 
Puttalam Road Direction 
16. Graph of Field Strength Vs Distance for Kurunegala Tx in 4.10 
Kandy Road Direction after removing points 
17. Map of Kurunegala shown with removed points 4.11 
List of Tables 
1. Technical Parameters of the Borella Base Station 3.1 
2. Technical Parameters of the Kottawa Base Station 3.2 
3. Technical Parameters of the Kurunegala Base Station 3.3 
4. Field Strength for Borella Transmitter in Orugodawatta Direction 4.1 
5. Field Strength for Borella Transmitter in Narahenpita Direction 4.2 
6. Field Strength for Borella Transmitter in Rajagiriya Direction 4.3 
7. Field Strength for Kottawa Transmitter 4.4 
8. Field Strength for Kurunegala Transmitter in Colombo Road Direction 4.5 
9. Field Strength for Kurunegala Transmitter in Dambulla Road Direction 4.6 
10. Field Strength for Kurunegala Transmitter in Kandy Road Direction 4.7 
11. Field Strength for Kurunegala Transmitter in Negombo Road Direction 4.8 
12. Field Strength for Kurunegala Transmitter in Puttalam Road Direction 4.9 
13. Results from the measurements 4.10 
14. Results from the ITU model 4.11 
15. Comparison of Propagation Constant 4.12 
16. Comparison of Field Strength 4.13 
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