# A STUDY OF GSM PROPAGATION ON UNILORIN CAMPUS USING WALFISCH-IKEGAMI MODEL

A STUDY OF GSM PROPAGATION ON UNILORIN CAMPUS USING WALFISCH-IKEGAMI MODEL

ABSTRACT

Land terrain and environmental contributors’ data are used extensively to predict propagation conditions, to optimally select locations for installing cellular base stations. There have been several models developed to predict the pattern of the losses attributed to propagated signals between two antennas (one at the cellular base station and the other at the mobile phone receiver). This project focuses on the use of the Walfisch-Ikegami model in predicting path loss of GSM signals within the University of Ilorin campus. This is done by comparing some measured data with calculated values.To determine the location where measurements were taken, the google earth application was used in conjunction with a GPS device. The measurement of the signals getting to the mobile devices was determined through a process of sending Attention commands (AT commands) through a personal computer’s serial port to mobile devices over a period of time as mentioned earlier. The phones are such that they are compatible with the AT commands instruction set (the reason being that not all phones can respond to these commands). An algorithm was developed for the calculation to be done using the theoretical Walfisch-Ikegami model. The measured values were compared with the results of the predictions to determine the suitability of the model for the selected areas within the University of Ilorin campus.

CHAPTER ONEINTRODUCTION                                        11.1 Overview                                        11.2 Motivation                                    2    1.3 Problem Statement                                21.4 Aim and Objectives                                31.4.1    Aim                                    31.4.2    Objectives                                31.5 Project Scope                                    31.6 Methodology                                    41.7Thesis Outline                                    4

CHAPTER TWOBACKGROUND AND RELEVANT LITERATURE                    52.1 Mobile Communication                                52.2GSM (Global System for Mobile Communication)                62.3Propagation Characteristics                            62.4Received signal power and attenuation            72.5Path loss Models                                    82.6The Walfisch-Ikegami Model                            102.7Past Works                                    132.8Base Station Heights Determination                        152.9AT Commands                                    15

CHAPTER THREEMETHODOLOGY AND CALCULATIONS                        183.1    Introduction                                    183.2    Location Selection                                183.3    Field Strength Data Logger                            193.4    Software Program Code                            203.5    System Set up Parameters                            253.6    AnalysisProcess                                25

CHAPTER FOURDATA ANALYSIS AND RESULTS IN 264.1    GPS Coordinates                                264.2    Distance between Points and Base Stations                274.3    Signal Strength Behaviour                            29    4.4    Comparison between Calculated and Measured Path losses        294.5    Discussion                                    33

CHAPTER FIVECHALLENGES, CONCLUSION, AND RECOMMENDATIONS            355.1    Summary and Conclusion                            355.2    Challenges on Studies                            355.3    Recommendations                                36REFERENCES AND BIBLIOGRAPHY                            37APPENDICES                                        I-    Table for Calculating W-I Path loss (GLO)                        41II-    Table for Calculating W-I Path loss (MTN)                        42III-    Table for Calculating W-I Path loss (AIRTEL)                    43IV-    List of Location, Coordinates, Distances, Signal Strengths, and Path Losses        44V-    Tables Used for Fig. 4.4.2 (a), (b) and (c) in order                    45

CHAPTER ONE INTRODUCTION

1.1 OVERVIEW

Growth in mobile telecommunications was met with great enthusiasm in Nigeria at its early stages but later resulted in frustration due to diminished quality of service (QoS)(1).  In Nigeria and many other countries, mobile communication has been troubled with complications spanning across human and technical issues. However, because good quality of service must have been enjoyed before the time of bad receptions, it becomes important to study the underlying reasons for such drop in signal quality delivered(2). Obstacles and surfaces within the vicinity of the device have an effect on the path characteristics (3). Signal propagation models then, are used largely in network planning, most especially for conducting feasibility studies and during initial deployment of mobile communications systems. They are also very useful for performing analyses on interference as the deployment of these networks proceed.

These models may be broadly categorized into three kinds namely; empirical, deterministic and stochastic. Empirical models are those based on observations and measurements alone. These models are mainly used to predict the path loss, but models that predict rain-fade and multipath have also been proposed. The deterministic models make use of the laws governing electromagnetic wave propagation to determine the received signal power at a particular location. Deterministic models often require a complete 3-D map of the propagation environment (e.g. ray-tracing model). Stochastic models, however, see the environment as a collection of random variables making them the least accurate but requiring very minimal information about the environment and make use much less processing power to generate their predictions (4).

The Walfisch-Ikegami model is an empirical model from J. Walfisch and F. Ikegami and was further developed by the COST 231 project. This is now called the COST- Walfisch-Ikegami Model. The accuracy of this model is limited to its consideration of buildings only in the vertical plane and quite high because in urban environments, multiple diffractions over rooftops are predominant. Wave guiding effects due to several reflections are not considered however, in the model(5).

1.2    Motivation

The study is borne out of the need to understand why hitherto good quality of service enjoyed by end users of GSM telecommunications suddenly deteriorates and in a way as to understand how physical and environmental factors play a part in this phenomenon.

1.3   Problem Statement

The problem addressed here is to compare the results of Walfisch-Ikegami model for pathloss with observed path loss by determiningthe strength of GSM signals at different locations of varied site parameters with respect to base stations’ within the University of Ilorin Campus.

1.4Aim and Objectives

1.4.1     Aim

The aim of the studies is to determine the suitability of the Walfisch-Ikegami model in the determination of path-loss and signal strength of mobile communication lines within the University of Ilorin Campus.

1.4.2     Objectives

The objectives in this project work are to:

i.            Measure signal strength and collect data and parameters for the verification of the Walfisch-Ikegami pathloss model.

ii.            Develop an algorithm for an application to calculate the Walfisch-Ikegami prediction model

iii.            Compare predicted with observed signal strength and consequent path-loss hence, identify the criteria determining the suitability and usefulness of the Walfisch-Ikegami path-loss model.

1.5Project Scope

The work done here, is focused on studying the behavior of propagated signals making use of the Walfisch-Ikegami pathloss model to predict the signal strength of which the Unilorin campus (located in Ilorin, Kwara state and covers about 75,000 hectares north and south) (6)serves as a quasi-laboratory to confirm the theory.The area of interest are characterized by sets of two-storey buildings that have evenly spaced pattern within the University of Ilorin campus.

1.6 Methodology

Determine path-loss parameters; Take readings of signal strength obtained from mobiles device using a named method; Compare  readings with the theoretical Walfisch-Ikegami path-loss model calculations; and hence make inferences from results

1.7Thesis Outline

Chapter twopresents essential and related background knowledge including the basics of path loss modelling paying credence to how the GSM works vis-à-vis features and GSM network parameter and workdone on the Walfisch-Ikegami Model. In Chapter three, a more detailed work is presented on the actual methodology employed in the course of the project work.

Chapter four analyses theoretical model calculation with respect to observed values. Comments and judgment are passed on the data obtained from the studies. Finally, chapter five summarizes the project work, avails recommendations and conclusions of the studies.

.

## TESTIMONIES FROM OUR CLIENTS

Please feel free to carefully review some written and captured responses from our satisfied clients.

• "I love what you guys are doing, your material guided me well through my research. Thank you for helping me achieve academic success."

Sampson, University of Nigeria, Nsukka.
• "researchwap.com is God-sent! I got good grades in my seminar and project with the help of your service, thank you soooooo much."

Cynthia, Akwa Ibom State University .
• "Sorry, it was in my spam folder all along, I should have looked it up properly first. Please keep up the good work, your team is quite commited. Am grateful...I will certainly refer my friends too."

Elizabeth, Obafemi Awolowo University
• "Am happy the defense went well, thanks to your articles. I may not be able to express how grateful I am for all your assistance, but on my honour, I owe you guys a good number of referrals. Thank you once again."

Ali Olanrewaju, Lagos State University.
• "My Dear Researchwap, initially I never believed one can actually do honest business transactions with Nigerians online until i stumbled into your website. You have broken a new legacy of record as far as am concerned. Keep up the good work!"

Willie Ekereobong, University of Port Harcourt.
• "WOW, SO IT'S TRUE??!! I can't believe I got this quality work for just 3k...I thought it was scam ooo. I wouldn't mind if it goes for over 5k, its worth it. Thank you!"

Theressa, Igbinedion University.
• "I did not see my project topic on your website so I decided to call your customer care number, the attention I got was epic! I got help from the beginning to the end of my project in just 3 days, they even taught me how to defend my project and I got a 'B' at the end. Thank you so much researchwap.com, infact, I owe my graduating well today to you guys...."

Joseph, Abia state Polytechnic.
• "My friend told me about ResearchWap website, I doubted her until I saw her receive her full project in less than 15 miniutes, I tried mine too and got it same, right now, am telling everyone in my school about researchwap.com, no one has to suffer any more writing their project. Thank you for making life easy for me and my fellow students... Keep up the good work"

Christiana, Landmark University .
• "I wish I knew you guys when I wrote my first degree project, it took so much time and effort then. Now, with just a click of a button, I got my complete project in less than 15 minutes. You guys are too amazing!."

Musa, Federal University of Technology Minna
• "I was scared at first when I saw your website but I decided to risk my last 3k and surprisingly I got my complete project in my email box instantly. This is so nice!!!."

Ali Obafemi, Ibrahim Badamasi Babangida University, Niger State.
• To contribute to our success story, send us a feedback or please kindly call 2348037664978.
Then your comment and contact will be published here also with your consent.

Thank you for choosing researchwap.com.