ADDIS ABABA UNIVERSITY ADDIS ABABA INSTITUTE OF TECHNOLOGY SCHOOL OF ELECTRICAL AND COMPUTER ENGINEERING Comparison and Fine Tuning Empirical Pathloss Models at 1800MHZ and 2100MHZ Bands for Addis Ababa, Ethiopia By Esayas Andarge Advisor Dr. -Ing. Dereje Hailemariam A Thesis Submitted to the School of Electrical and Computer Engineering of the Addis Ababa Institute of Technology, Addis Ababa University in Partial Fulfillment of the Requirements for the Degree of Masters of Science in Telecommunications Engineering October, 2018 Addis Ababa, Ethiopia ADDIS ABABA UNIVERSITY ADDIS ABABA INSTITUTE OF TECHNOLOGY SCHOOL OF ELECTRICAL AND COMPUTER ENGINEERING Comparison and Fine Tuning Empirical Pathloss Models at 1800MHZ and 2100MHZ Bands for Addis Ababa, Ethiopia By Esayas Andarge Approval by Board of Examiners _____________________________ ____________ Chairman, School Graduate committee Signature Committee Dr. -Ing. Dereje Hailemariam ____________ Advisor Signature ______________________________ ____________ Internal Examiner Signature _____________________________ ____________ External Examiner Signature Declaration I, the undersigned, declare that this thesis is my original work, has not been presented for a degree in this or any other university, and all sources of materials used for the thesis have been fully acknowledged. Esayas Andarge ______________ Name Signature Place: Addis Ababa Date of Submission: _______________ This thesis has been submitted for examination with my approval as a university advisor. Dr. -Ing. Dereje Hailemariam ______________ Advisor’s Name Signature 3 Abstract Pathloss models play a very important role in wireless communications in coverage planning, interference estimations, frequency assignments, Location Based Services (LBS), etc. They are used to estimate the average pathloss a signal experience at a particular distance from a transmitter. Inaccurate propagation models may result in poor coverage, poor quality of service or high investment cost. Both second generation (2G) and third generation (3G) networks in the city of Addis Ababa (AA), Ethiopia, have problems like poor coverage, low data throughput, call drops and others. One of the root causes of these problems is the use of untuned pathloss model during network planning. So, it is mandatory for the operators to select the best fit pathloss model and tune it according to the specific situation the pathloss model is used. This thesis compares three pathloss models; namely, COST231, ECC-33 and SUI and tunes the one that performs best in the specific area type. At 1800MHZ band, COST231 was best in estimating the measured path loss in urban areas with a Root Mean Squared Error (RMSE) of 3.27dB before tuning and the RMSE could improve to 3.25dB after tuning. COST231 was also best in suburban areas with an RMSE of 5.27dB. Tuning the model could improve the RMSE to 4.18dB. SUI was best in open areas. It has an RMSE value of 6.0dB before tuning. Tuning has improved the RMSE value to 4.91dB. At 2100MHZ, 25 sites are used to collect path loss data. Similar analysis was done in the three path loss models. Based on the analysis, SUI is found to be best in predicting the path loss for all the three morphology types. Although ECC-33 was equally competent for urban area sites, SUI could predict the path loss better for the overall all average measured path loss with an RMSE of 4.27dB. Tuning the model could improve the RMSE to 2.23dB. The measured path loss for suburban areas could also be better predicted by SUI with an RMSE value of 5.75dB before tuning and 2.57dB after tuning. Path loss in open areas can also be better predicted by SUI. It has an RMSE value of 6.53dB before tuning. An improvement in RMSE to 3.38dB could be achieved after tuning. Keywords — Path loss, tuning, prediction, modelling, error, urban, suburban, open. 4 Acknowledgment First and foremost I would like to praise the almighty God for helping me in every regard of my life. Next, I would like to give my heartfelt thanks to Dr. -Ing. Dereje Hailemariam, without whom this thesis would have been only a merely wish. I really appreciate the effort, benevolence and expertize support he showed for all students under his supervision. I would also like to thank Mr. Ashagrie Getinet, Department head of Engineering in ethio telecom, for his idea sharing towards this work and allowing his staffs to support me for data collection. My thanks also go to the manager and supervisors of GSM and UMTS teams in Radio Access Network (RAN) section of engineering department. A lot of their staffs have been supportive and I would like to thank for all. The last but not the least, a special thanks go to Ato Tamiru Gizaw, a staff in GSM team and now an intimate friend, for his support in collecting the majority of the field data and his encouragement. He is one of the most benevolent men I have ever probably met in my life including his family. 5 Table of Content Declaration .................................................................................................................................................... 3 Abstract ......................................................................................................................................................... 4 Acknowledgment .......................................................................................................................................... 5 List of Figures ................................................................................................................................................ 8 List of Tables ............................................................................................................................................... 10 List of Acronyms .......................................................................................................................................... 12 1. Introduction .................................................................................................................................... 13 1.1. Statement of the Problem .......................................................................................................... 14 1.2. Objective ..................................................................................................................................... 15 1.2.1. General Objective ............................................................................................................... 15 1.2.2. Specific Objectives .............................................................................................................. 15 1.3. Scope and Limitation of the thesis .............................................................................................. 16 1.3.1. Scope ................................................................................................................................... 16 1.3.2. Limitation ............................................................................................................................ 16 1.3.3. Literature Review ................................................................................................................ 16 1.4. Methodology ............................................................................................................................... 19 1.5. Contribution of the Thesis .......................................................................................................... 19 1.6. Thesis Layout ............................................................................................................................... 20 2. Cellular Network Coverage Planning .............................................................................................. 21 2.1. Cellular Network Coverage Planning processes.......................................................................... 22 2.2. Pathloss Models Review ............................................................................................................. 25 2.2.1. Empirical Models ................................................................................................................. 27 2.2.2. Semi-empirical Models ....................................................................................................... 27 2.2.3. Deterministic Models .......................................................................................................... 28 2.3. Propagation Models for Cellular Network Planning ................................................................... 34 2.4. Analysis of Propagation Models (COST231, SUI and ECC-33) ..................................................... 36 2.4.1. Stanford University Interim (SUI) Model ............................................................................ 37 6 2.4.2. ECC-33 ................................................................................................................................. 41 2.4.3. COST231 .............................................................................................................................. 45 3. Radio Wave Propagation ................................................................................................................ 50 3.1. Basics of Propagation .................................................................................................................. 51 3.2. Small Scale Effects and Large Scale Effects ................................................................................. 52 3.3. Fading Channels