Georgia Southern University Digital Commons@Georgia Southern Electronic Theses and Dissertations Graduate Studies, Jack N. Averitt College of Fall 2020 Analysis of Antenna Designs for the Maximum Power Transmission Lauryn P. Smith Follow this and additional works at: https://digitalcommons.georgiasouthern.edu/etd Part of the Electromagnetics and Photonics Commons, and the Other Electrical and Computer Engineering Commons Recommended Citation Smith, Lauryn P., "Analysis of Antenna Designs for the Maximum Power Transmission" (2020). Electronic Theses and Dissertations. 2181. https://digitalcommons.georgiasouthern.edu/etd/2181 This thesis (open access) is brought to you for free and open access by the Graduate Studies, Jack N. Averitt College of at Digital Commons@Georgia Southern. It has been accepted for inclusion in Electronic Theses and Dissertations by an authorized administrator of Digital Commons@Georgia Southern. For more information, please contact [email protected]. ANALYSIS OF ANTENNA DESIGNS FOR THE MAXIMUM POWER TRANSMISSION by LAURYN SMITH (Under the Direction of Sungkyun Lim) ABSTRACT Since Nikola Tesla discovered wireless power transmission, it has become a very interesting topic of study in the antennas and wireless propagation community. Various aspects and applications for wireless power transmission are studied today, a few of which are investigated in this work. First, various antenna geometries are analyzed for radiative near-field wireless power transfer in terms of electrical field strength. It is determined that the meander antenna is ideal for maximum power transfer in its radiative near-field region, contrary to its far-field behavior. Next, in the application of radio frequency identification, a directive, UHF RFID tag antenna is designed for pavement embedded applications. The antenna covers 72% of the US required bandwidth (902 – 928 MHz) in measurement and has maximum directivity and read range of 7.38 dBi and 14.2ft (4.3 m), respectively. Although the transmitter and receiver antennas' designs are essential parts of the wireless system, power loss to the wireless channel is another critical factor to consider in ensuring the receiver antenna receives the maximum power. Friis transmission equation is studied in detail, and a section of the Georgia Southern University campus is considered for full cellular coverage in the GSM frequency range. Additionally, using the genetic algorithm in parallel, the optimal position for a 60-GHz wireless router is determined to obtain maximum WIFI coverage in a specific house. Finally, the design procedure for a size-reduced, 15-element Yagi antenna is discussed. A comprehensive comparison is conducted demonstrating the importance of the antenna design, with its similar performance to the full-sized Yagi antenna, while its elements are reduced by 45%. INDEX WORDS: Directive, High gain, Propagation modeling, Radiative near-field wireless power transfer, Radio frequency identification, Wireless power transfer, Wireless power transmission. ANALYSIS OF ANTENNA DESIGNS FOR THE MAXIMUM POWER TRANSMISSION by LAURYN SMITH B.S., Georgia Southern University, 2018 M. S., Georgia Southern University, 2020 A Thesis Submitted to the Graduate Faculty of Georgia Southern University in Partial Fulfillment of the Requirements for the Degree MASTER OF SCIENCE COLLEGE OF ENGINEERING AND COMPUTING © 2020 LAURYN SMITH All Rights Reserved 1 ANALYSIS OF ANTENNA DESIGNS FOR THE MAXIMUM POWER TRANSMISSION by LAURYN SMITH Major Professor: Sungkyun Lim Committee: Mohammad Ahad Fernando Rios Electronic Version Approved: December 2020 2 DEDICATION First and foremost, I would like to thank my amazing parents. Without their love, support and sacrifice this would not be possible. I would also like to thank my family and friends for their support and encouragement throughout my program. 3 ACKNOWLEDGMENTS I would like to thank my research advisor and mentor, Dr. Sungkyun Lim for giving me the opportunity to obtain this degree and for seeing my potential and always pushing me to reach it. I would also like to thank my committee members, Dr. Rios and Dr. Ahad, for taking the time to review my thesis. Finally, I extend my thanks to Kevin Leon for his help with measurements for publications, so that I could focus on my thesis. 4 TABLE OF CONTENTS Page ACKNOWLEDGMENTS . 3 LIST OF TABLES . 6 LIST OF FIGURES . 7 CHAPTER 1 INTRODUCTION . 11 1.1 Wireless Power Transmission . 11 1.1.1 History of Wireless Power Transmission . 11 1.1.2 Wireless Power Transfer Background . 12 1.2 High Gain Antennas . 13 1.3 Electrical Size and Size Reduction . 15 1.4 Radio Frequency Identification . 17 1.5 Wireless Propagation Modelling . 18 1.6 Thesis Objective . 19 2 ANALYSIS OF ANTENNA GEOMETRIES FOR NEAR-FIELD WIRELESS POWER TRANSFER . 21 2.1 Introduction . 21 2.2 Antenna Designs . 22 2.3 Simulation Results . 24 2.4 Summary . 27 3 DESIGN OF A DIRECTIVE, UHF RFID TAG ANTENNA FOR PAVEMENT EMBEDDED APPLICATION . 29 3.1 Introduction . 29 3.2 Initial Antenna Design . 30 5 3.2.1 Design Procedure . 30 3.2.2 Simulation and Measurement Results . 32 3.3 Final Antenna Design. 34 3.3.1 Design Procedure . 34 3.3.2 Simulation and Measurement Results . 35 3.4 Summary . 39 4 INVESTIGATION INTO WIRELESS PROPAGATION . 40 4.1 Friis Transmission Equation . 40 4.2 Maximizing Cellular Coverage on the Georgia Southern University Campus . 43 4.2.1 Introduction . 43 4.2.2 Buildings Simulation . 45 4.2.3 Buildings and Trees Simulation . 48 4.2.4 Implementation of Repeater for Maximum GSM Cell Coverage . 50 4.3 Parallel Optimization for maximum WIFI signal in indoor environment . 52 4.3.1 Introduction . 52 4.3.2 Simulation Framework and Results . 53 4.4 Summary . 56 5 FURTHER ANALYSIS IN A SIZE-REDUCED, 15-ELEMENT PLANAR YAGI ANTENNA.. 57 5.1 Abstract . 57 5.2 Design Procedure. 57 5.3 Current Distribution . 62 5.4 Antenna Comparison . 62 5.5. Summary . 64 6 CONCLUSIONS. 65 REFERENCES . 67 6 LIST OF TABLES Page Table I: Parametric Study of Mult and Feed Location for S11 . 31 Table II: Parametric Study of Mult and Feed Location for Input Impedance . 31 Table III: Comparison Between the Presented and the Commercial Tag Antennas . 38 Table IV: Repeater Position Comparison . 52 Table V: T-Shaped, Top-Loaded Dipoles Comparison . 60 Table VI: Size-Reduced Yagi Comparison with Different Number of Elements . 61 Table VII: Comparison of Size-Reduced Yagi Antennas . 63 Table VIII: Comparison of Proposed Yagi Antenna with LPDA Antennas . 64 7 LIST OF FIGURES Page Fig. 1.1: The Field Regions of an Antenna [7] . 12 Fig. 1.2: The Conventional /2 Yagi Antenna . 14 Fig. 1.3: Effect of an Increased Number if Yagi Antenna Elements on Gain [12] . 15 Fig. 1.4: The Radius of the Smallest Sphere that Encloses the Antenna . 16 Fig. 1.5: Methods of Antenna Size Reduction: (a) Folding [23] and (b) top-loading [31] . 17 Fig. 1.6: (a) Higgs 3 RFID Chip and (b) Commercially Available RFID Tag Antenna . 18 Fig. 2.1: Antenna Geometries Investigated for Radiative Near-Field WPTL (a) Archimedean Spiral Antenna, (b) Patch Antenna, (c) Full-Sized dipole antenna, (d) Full-Sized, Three-Element Yagi Antenna, (e) 0.8 kr Directive Antenna and (f) 0.8 kr Meander Antenna . 23 Fig. 2.2: Simulated S11 for the Antenna Geometries shown in Fig. 2.1 . 25 Fig. 2.3: Simulated E-Field for the Antenna Geometries shown in Fig. 2.1 . 25 Fig. 2.4: The E-Field for the Antennas Included in Group 1: The Spiral Antenna, 0.8 kr Directive Antenna, and the 0.8 kr Meander Antenna . 26 Fig. 2.5: The E-Field for the Antennas Included in Group 2: The Patch Antenna, The Full-Sized Dipole, and the Full-Sized, 3-Element Yagi Antenna . 27.