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X Band Substrate Integrated Horn Array Antenna For X BAND SUBSTRATE INTEGRATED HORN ARRAY ANTENNA FOR FUTURE ADVANCED COLLISION AVOIDANCE SYSTEM by AMEYA RAMADURGAKAR B.S., Drexel University, 2011 A thesis submitted to the Graduate Faculty of the University of Colorado Colorado Springs in partial fulfillment of the requirements for the degree of Master of Science Department of Electrical and Computer Engineering 2015 © Copyright By Ameya Ramadurgakar 2015 All Rights Reserved ii iii To my parents, Surésh and Alka, for their infinite love, support, and to my sister Aditi for her everlasting love and encouragement iv ACKNOWLEDGMENTS: My paramount appreciation goes to my academic advisor Dr. Heather Song (University of Colorado Colorado Springs) for her non-stop advice over the progress of my thesis research and providing all conditions to keep my work running. I equally appreciate the valuable feedback, guidance and help from Dr. James Lovejoy (Lockheed Martin) for his stellar comments, critic and ideas throughout the thesis. I would also appreciate my deepest gratitude to Dr. T.S. Kalkur (University of Colorado Colorado Springs) for his overarching support throughout the completion of my degree. Last but in no ways the least, I most appreciate the help of Kevin Quillen (ANSYS) for showing me the ropes and tricks of using the HFSS software over many sessions. v TABLE OF CONTENTS CHAPTER I. INTRODUCTION __________________________________________________ 1 1.1. Overview of Collision Avoidance System _________________________________________________________ 2 1.1.1 Automated Dependent Surveillance - broadcast(ADS-B) _____________________________________ 2 1.1.2 Traffic Collision Avoidance System (TCAS) __________________________________________________ 4 1.2 State of the Art UAV Collision Avoidance System _________________________________________________ 6 1.3 Literature Search and Review _______________________________________________________________________ 7 1.4 Novelty of the Proposed Thesis Work ______________________________________________________________ 8 1.5 Scopes and Motivations of Thesis ___________________________________________________________________ 9 II. BACKGROUND AND THEORY ___________________________________ 13 2.1. Horn Antenna ______________________________________________________________________________________ 14 2.1.1 H-Plane sectoral horn __________________________________________________________________________ 14 2.2 Array Antenna ______________________________________________________________________________________ 19 2.2.1 Broadside Array Antenna ______________________________________________________________________ 21 2.2.1 End fire Array Antenna ________________________________________________________________________ 23 2.3 Dielectrically Filled Waveguide____________________________________________________________________ 24 2.4 Radar Range Equation ______________________________________________________________________________ 29 2.5 Microstrip ___________________________________________________________________________________________ 33 2.6 Summary of Theory ________________________________________________________________________________ 34 III. DESIGN _______________________________________________________ 35 3.1 Radar Range Equation (RRE) Calculations ________________________________________________________ 36 3.1.1 Design Calculations and Plots ________________________________________________ 36 3.2 Computer Design and Simulation __________________________________________________________________ 44 3.2.1 Waveguide Design and Simulation ___________________________________________ 44 3.2.2 Antenna Design and Simulation ______________________________________________ 46 3.2.3 Microstrip to SIW Feed Transition and Network Design __________________________ 49 3.2.4 Single Antenna Element Design and Simulation ________________________________ 50 3.3 Array Antenna Design and Simulation _____________________________________________________________ 52 3.4. Feeding Network Technique Analysis and Application ___________________________________________ 59 3.5. Methods to Enhancing Performance in Array Antennas __________________________________________ 76 IV. MEASUREMENT AND RESULT DISCUSSION _____________________ 80 4.1 Antenna Gain Measurement Techniques ___________________________________________________________ 80 4.1.1 Three Antenna Gain Measurement Technique __________________________________ 83 4.2 Calculated, Simulated and Measured Array Facto _________________________________________________ 84 4.3 Experiment Setup ___________________________________________________________________________________ 86 4.3.1 S11 Measurement Test _________________________________________________________________________ 86 4.3.2 Radiation Pattern Setup _______________________________________________________________________ 90 4.3.3 Gain Measurement Setup ______________________________________________________________________ 94 V. CONCLUSION AND FUTURE WORK ______________________________ 98 REFERENCES ____________________________________________________ 101 APPENDICES _____________________________________________________ 104 RADAR RANGE EQUATION ____________________________________________________________________ 104 Subsrate Integrated Waveguide Dimension Calculator Code ___________________________ 116 Array Factor calculator and radiation pattern plotter ______________________________________________ 120 vi TABLES Table 1-1: Basic system requirement (compatible with 1090 ES) ..................................... 2 Table 1-2: Link Budget calculation for ADS-B system..................................................... 2 Table 1-3: TCAS Levels of Protection ............................................................................... 4 Table 1-4: Previous and currently related research and work. ............................................ 9 Table 1-5: Final specification of the proposed design thesis array antenna ..................... 12 Table 2-1: Constant K1 in a Two Way Radar Range Equation ........................................ 22 Table 2-2: Constant K2 in a Two Way Radar Range Equation. ....................................... 22 Table 3-1: Gain Range vs Scan Range. ............................................................................ 33 Table 3-2: Simulated Antenna Elements vs. Gain and Scan Range. ................................ 47 Table 3-3: Number of Elements vs Element Spacing Study Results. ............................... 66 Table 4-1: Return Loss Test Measurement Equipment Used ........................................... 87 Table 4-2: Details of Components Used in Radiation Pattern Measurement ................... 90 Table 4-3: Antennae Dimensions and Far Field Criterion ................................................ 93 Table 4-4: Component Listing for Gain Measurement Experiment ................................. 97 Table 4-5: Main Lobe Measured Absolute Gain .............................................................. 98 vii FIGURES Figure 1-1: TCAS II Block Diagram .................................................................................. 6 Figure 2-1: H-Plane horn .................................................................................................. 14 Figure 2-2: H-Plane (x-z) cut of an H-plane sectorial horn .............................................. 15 Figure 2-3: E and H normalized plane patterns for H plane sectoral horn ....................... 17 Figure 2-4: E and H normalized plane patterns for H plane sectoral horn ....................... 18 Figure 2-5: Array Factor/Pattern Multiplication ............................................................... 20 Figure 2-6: Broadside Array Radiation pattern ................................................................ 21 Figure 2-7: Array factor patterns of a 10-element uniform amplitude broadside array .... 22 Figure 2-8: Three-dimensional amplitude patterns for end-fire arrays toward 0 and 180 degrees .............................................................................................................................. 23 Figure 2-9: Array Factor patterns for ordinary end fire array at different phase excitation ........................................................................................................................................... 24 Figure 2-10: Geometry of the dielectric slab waveguide (a) Perspective view (b) Side View .................................................................................................................................. 25 Figure 2-11: Substrate Integrated Waveguide .................................................................. 26 Figure 2-12 Dimension definition of rectangular waveguide ........................................... 27 Figure 2-13: Pitch ‘p’ and Diameter‘d’ of the SIW .......................................................... 29 Figure 2-14: Monostatic Array Antenna System .............................................................. 30 Figure 2-15: Equivalent Circuit Model of the RRE .......................................................... 30 Figure 2-16: A typical cross section view of a microstrip line ......................................... 33 Figure 3-1: Thesis Design Cornerstones ........................................................................... 35 Figure 3-2: MATLAB generated value for Range ............................................................ 37 viii Figure 3-3: MATLAB plot of Range vs. Receiver Sensitivity with TX and RX Gain = 10dB .................................................................................................................................
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