FPGA-BASED COHERENT DOPPLER PROCESSOR FOR MARINE RADAR APPLICATIONS Dissertation Submitted to The School of Engineering of the UNIVERSITY OF DAYTON In Partial Fulfillment of the Requirements for The Degree of Doctor of Philosophy in Engineering By Hamdi Eltayib Abdelbagi Dayton, Ohio May 2016 FPGA-BASED COHERENT DOPPLER PROCESSOR FOR MARINE RADAR APPLICATIONS Name: Abdelbagi, Hamdi Eltayib APPROVED BY: __________________________________ ________________________________ Michael C. Wicks, Ph.D. Eric Balster, Ph.D. Advisory Committee Chairman Committee Member Ohio Research Scholar Endowed Chair in Associate Professor, Department of Sensor Exploitation and Fusion; Electrical and Computer Engineering Distinguished Research Engineer, Department of Electrical and Computer Engineering ___________________________________ _______________________________ Guru Subramanyam, Ph.D. Lorenzo Lo Monte, Ph.D. Committee Member Committee Member Chairperson of Department of Adjunct Professor, Department Electrical and Computer Engineering of Electrical and Computer Engineering ____________________________________ ________________________________ John G. Weber, Ph.D. Eddy M. Rojas, Ph.D., M.A., P.E. Associate Dean, School of Engineering Dean, School of Engineering ii © Copyright by Hamdi Eltayib Abdelbagi All Right Reserved 2016 iii ABSTRACT FPGA-BASED COHERENT DOPPLER PROCESSOR FOR MARINE RADAR APPLICATIONS Name: Abdelbagi, Hamdi Eltayib University of Dayton Advisor: Dr. Michael C. Wicks The goal of this research is to develop a method for affordable and reliable sampling and coherent processing of measurement data collected via a modified magnetron oscillator based marine radar system. Non-coherent low-priced marine radar systems offer limited surveillance in clutter rich environments as compared to more expensive and complex coherent solid state radar systems. The approach used herein leverages modern analog to digital converters (ADC) and field programmable gate array (FPGA) technology to affordably and effectively sample the radiated and received signals for further analysis using FFT-based Doppler processing or cross correlation analysis. Track processing of moving targets is fundamental to any advanced radar and is a further focus of this research. The marine radar hardware is modified to capture the transmit signal at the source, and the receive signal at the aperture, for processing via FPGAs. The receive pulse train is cross-correlated with the transmit pulse train reference to remove the uncertainties in the phase history of the collected data. This operation ultimately makes the radar fully coherent on receive. Once the receive signal is made coherent, classical iv Doppler processing is used to differentiate moving targets from clutter and electromagnetic interference. A real time system has been built on a board with ADCs, FPGAs, and a microprocessor. Mixing of the Transmit (TX) and the Receive (RX) signals, Fourier transform analysis, and Pulse Compression are all executed digitally in the FPGA whereas Doppler Processing is performed on the microprocessor. This paper presents the underlying principles of cohering signals on receive, and it will show a real- time implementation of such algorithms using FPGAs. v To my loving parents, my family, and my friends vi ACKNOWLEDGEMENTS First, I would like to thank Dr. Michael C. Wicks, my advisor, for his expert guidance and encouragement. His dedication and insightful guidance have significantly contributed to the successful completion of this work. My thanks also go to Dr. Lorenzo Lo Monte, Dr. Eric Blaster, Dr. Guru Subramanyam for helping me through my Ph.D. journey and serving as Ph.D. committee members, and also to Mansour Aljohani for his help in experimentation and data collection. I would like to thank the Electrical and computer engineering department for offering the convenient and the suitable atmosphere to accomplish this work. Finally, I would like to thank my parents, my brothers, my wife and my friends for their love and support. They have been a great source of inspiration and encouragement throughout my life. vii TABLE OF CONTENTS ABSTRACT ................................................................................................................................... iv ACKNOWLEDGEMENTS ........................................................................................................... vii LIST OF FIGURES ........................................................................................................................ ix LIST OF ABBREVIATIONS AND NOTATION .......................................................................... xi CHAPTER 1 INTRODUCTION AND LITERATURE REVIEW .................................................. 1 1.1 Introduction ......................................................................................................................... 1 1.2 Literature Review ............................................................................................................... 3 CHAPTER 2 BACKGROUND AND BRIEF DESCRIPTION OF INVENTION ......................... 5 2.1 Background ......................................................................................................................... 5 2.1.1 Non-coherent radar ....................................................................................... 5 2.1.2 Coherent radar ............................................................................................... 8 2.2 Brief Description of Invention .......................................................................................... 10 CHAPTER 3 INVENTION APPROACH .................................................................................... 12 3.1 Details Invention Approach .............................................................................................. 12 CHAPTER 4 PROOF OF CONCEPT .......................................................................................... 20 4.1 Proof Of Concept .............................................................................................................. 20 CHAPTER 5 THE INVENTION’S DESIGN ............................................................................... 32 5.1 The Analog Part ................................................................................................................ 32 5.2 The FPGA Part ................................................................................................................. 34 5.3 The Resources and Schematics: ........................................................................................ 38 CHAPTER 6 FINDING AND RESULTS .................................................................................... 49 6.1 Findings ............................................................................................................................ 49 6.2 Results .............................................................................................................................. 69 CHAPTER 7 CONCLUSION ....................................................................................................... 72 BIBLIOGRAPHY ......................................................................................................................... 73 viii LIST OF FIGURES Figure 1: Standard Marine Radar System ....................................................................................... 5 Figure 2: Standard coherent radar system ............................................................................8 Figure 3: Our invention, modified marine radar ........................................................................... 10 Figure 4: Modified Marine Radar hardware ................................................................................. 14 Figure 5: The captured TX signal. ................................................................................................ 15 Figure 6: 2-D Data Matrix of coherent, baseband returns for M pulses and L range bins. ........... 17 Figure 7: FFT of the received signal to expound a Doppler shift. ................................................ 17 Figure 8: Moving Target Indication (MTI) Filter. ........................................................................ 18 Figure 9: Doppler spectrum after Moving Target Indication filtering process. ............................ 19 Figure 10: The oscilloscope's capture for the transmitter and the receiver. .................................. 22 Figure 11: 3D for the transmitted signal. ...................................................................................... 23 Figure 12: 3D for the received signal. ........................................................................................... 24 Figure 13: 3D for the received signal. ........................................................................................... 25 Figure 14: 3D for the received signal. ........................................................................................... 25 Figure 15: I TX data. ..................................................................................................................... 26 Figure 16: I RX data. .................................................................................................................... 26 Figure 17: Q TX data. ................................................................................................................... 27 Figure 18: Q RX data. ..................................................................................................................