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Propagation Analysis of a 900 Mhz Spread Spectrum Centralized Traffic Signal Control System

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Propagation Analysis of a 900 Mhz Spread Spectrum Centralized Traffic Signal Control System PROPAGATION ANALYSIS OF A 900 MH Z SPREAD SPECTRUM CENTRALIZED TRAFFIC SIGNAL CONTROL SYSTEM Brian L. Urban, AS, BS, EIT Thesis Prepared for the Degree of MASTER OF SCIENCE UNIVERSITY OF NORTH TEXAS May 2006 APPROVED: Perry McNeill, Major Professor Michael Kozak, Committee Member Shuping Wang, Committee Member Bernard Vokoun, Committee Member Vijay Vaidyanathan, Departmental Program Coordinator Albert B. Grubbs, Chair of the Department of Engineering Technology Oscar Garcia, Dean of the College of Engineering Sandra L. Terrell, Dean of the Robert B. Toulouse School of Graduate Studies Urban, Brian L., Propagation analysis of a 900 MHz spread spectrum centralized traffic signal control system. Master of Science (Engineering Technology), May 2006, 88 pp., 20 tables, 27 illustrations, references, 25 titles. The objective of this research is to investigate different propagation models to determine if specified models accurately predict received signal levels for short path 900 MHz spread spectrum radio systems. The City of Denton, Texas provided data and physical facilities used in the course of this study. The literature review indicates that propagation models have not been studied specifically for short path spread spectrum radio systems. This work should provide guidelines and be a useful example for planning and implementing such radio systems. The propagation model involves the following considerations: analysis of intervening terrain, path length, and fixed system gains and losses. Copyright 2006 by Brian L. Urban ii ACKNOWLEDGEMENTS I acknowledge the following people for their efforts and contributions to my thesis. It would not have been completed without them. Special thanks to the author’s thesis advisor, Dr. Perry R. McNeill, for his guidance, patience support, encouragement and stimulation in my graduate study and research. I thank Dr. Michael Kozak, member of my thesis committee for his guidance throughout my graduate program and for his suggestions in completing this document. I thank Dr. Shuping Wang for her willingness and graceful acceptance to serve as a committee member on short notice. I thank my industrial advisor, Mr. Bernard Vokoun, P.E. Senior Traffic Engineer for the City of Denton for his guidance, suggestions and comments. I thank Mr. Scott Wilson, Lead Electronic Traffic Signal Technician, City of Denton, for his cooperation and willingness to provide assistance in completing this work. I thank Dr. Albert Grubbs, Chair of the Engineering Technology Department for his continued encouragement and support. I thank all faculty and staff members of the Department of Engineering Technology for their continued encouragement in seeing this work brought to a successful conclusion. I thank my wife, Virginia, and daughter, Carmen, for their encouragement and support in helping me complete my thesis. iii TABLE OF CONTENTS Page ACKNOWLEDGMENTS ...........................................................................................................iii LIST OF TABLES.......................................................................................................................vi LIST OF ILLUSTRATIONS......................................................................................................vii Chapters 1. INTRODUCTION ................................................................................................ 1 Impact of Traffic Signal Control............................................................... 1 Proposed Centralized Signal Control System........................................... 2 Object of the Research.............................................................................. 5 Significance of the Problem...................................................................... 5 Statement of the Problem.......................................................................... 5 Research Question .................................................................................... 5 Hypotheses................................................................................................ 6 Significance of the Research..................................................................... 6 Assumptions.............................................................................................. 7 Limitations ................................................................................................ 7 Definitions................................................................................................. 7 Expected Outcomes .................................................................................. 8 Summary................................................................................................... 8 2. RADIO FREQUENCY PROPAGATION MODELS AND METHODS ............ 9 Basic Propagation Theory....................................................................... 11 Radio Path Signal Strength Budgets....................................................... 14 Signal Strength Losses in RF Propagation.............................................. 15 Fresnel Zones Effects on Signal Strength............................................... 19 Okumura’s Radio Propagation Prediction Model................................... 21 Carey’s Radio Propagation Prediction Model ........................................ 22 Damelin’s Radio Propagation Prediction Model .................................... 25 Bullington’s Radio Propagation Prediction Model................................. 27 Epstein-Peterson Diffraction Method ..................................................... 29 iv Joint Radio Committee Model................................................................ 29 Allsebrooks Model.................................................................................. 30 Lee’s Model ............................................................................................ 31 COST 231-Hata Model........................................................................... 33 Longley-Rice Model ............................................................................... 34 Hata Model.............................................................................................. 35 Conclusion .............................................................................................. 37 3. USING THE HATA MODELIN PREDICTING RADIO FREQUENCY PROPAGATION ................................................................................................ 37 Research Method .................................................................................... 39 Sites Selected for Study .......................................................................... 40 Data Collection Methodology................................................................. 45 Adjusting to Received Signal Data Values............................................. 47 Data Analysis.......................................................................................... 49 Fresnel Zone Considerations................................................................... 52 Terrain Data Extraction and Analysis..................................................... 54 Conclusion .............................................................................................. 57 4. DATA ANALYSIS OF THE HATA MODEL OF PATH PROPAGATION PREDICTION..................................................................................................... 54 Analysis Methodology............................................................................ 59 Hypothesis Testing.................................................................................. 61 5. CONCLUSION AND RECOMMENDATIONS ............................................... 65 Recommendations................................................................................... 65 Appendices A. TERRAIN DATA............................................................................................... 66 B. PATH LOSS CALCULATIONS........................................................................ 79 REFERENCE LIST .................................................................................................................... 85 v LIST OF TABLES Page 1. Propagation Environments.............................................................................................. 16 2. Values of P0 and γ for Selected Environments ............................................................... 32 3. Site Parameter Summary................................................................................................. 44 4. Insite 6i™ Received Signal Strength Data ..................................................................... 49 5. Insite 6i™ Received Signal Strength Data ..................................................................... 50 6. Data Values for Hata Model Variations.......................................................................... 59 7. Lillian Miller at Hickory Creek Terrain Data................................................................. 67 8. Lillian Miller at Teasley Lane Terrain Data ................................................................... 68 9. McKinney at Loop 288 Terrain Data.............................................................................. 69 10. Lillian Miller at IH35E Terrain Data.............................................................................. 69 11. Lillian Miller at Southridge Village Terrain Data .......................................................... 70 12. Lillian Miller at Southridge Terrain
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