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Spatial Positioning with Wireless Chirp Spread Spectrum Ranging

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JACOBS UNIVERSITY BREMEN Spatial Positioning with Wireless Chirp Spread Spectrum Ranging by Hamed Bastani A thesis submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Smart Systems School of Engineering and Science Defense date: 13 November 2009 ii Spatial Positioning with Wireless Chirp Spread Spectrum Ranging by Hamed Bastani thesis submitted in partial fulfillment for the degree of Doctor of Philosophy in Faculty of Smart Systems School of Engineering and Science Jacobs University Bremen APPROVED: Prof. Dr. Andreas Birk Supervisor, Dissertation Committee Head (Jacobs University Bremen, Germany) Prof. Dr. J¨urgenSch¨onw¨alder Dissertation Committee Member (Jacobs University Bremen, Germany) Dr. Holger Kenn Dissertation Committee Member (European Microsoft Innovation Center, Aachen, Germany) Electronic Version (10 Dec. 2009), Information Resource Center, Jacobs University. Declaration of Authorship This dissertation is submitted in partial fulfillment of requirements for a PhD degree in Smart Systems from the School of Engineering and Science at Jacobs University Bremen. The author declares that the work presented here is his own, to the best of his knowledge and belief, is written independently and has not been submitted substantially or as a whole at another University or institution for con- ferral of any other degree. The effort was done mainly while in candidature for a professional degree at this university. Where any part of this material has previ- ously been submitted in the form of a journal or conference contribution, it has been stated. Respecting the copyright boundaries, the author may use partially some parts of this thesis in the future for potential publications, investigations or improvements. Experimental results and analysis are original and achieved through pure implementation. Occasionally in the surveys, for comparison or as basic definitions, the presented material might have consulted the published ef- forts of others, this is always clearly attributed by proper citations. Meanwhile, all sources of help are clearly acknowledged. On the other hand, brief quotations from this dissertation are allowable without special permission, provided that accurate acknowledgment of the source is made. Requests for permission for extended quo- tation from or reproduction of this manuscript in part may be granted by the Dean of the School in his judgment for the proposed use of the material limited to the interests of education. In all other instances, however, permission must be obtained from the author. Hamed Bastani Bremen, 30 October 2009. i \Whoever acquires knowledge and does not practice it resembles him who plows his land and leaves it unsown." -- Muslihudin Sadi Shirazi (1184 { 1283) \The world stands aside to let those pass who know where they are going." -- Dottie Walters JACOBS UNIVERSITY BREMEN School of Engineering and Science Doctor of Philosophy, Faculty of Smart Systems by Hamed Bastani Spatial Positioning with Wireless Chirp Spread Spectrum Ranging Abstract Euclidean distance ratios between networked nodes can be represented by the weight values of a subset of multidimensional graph edges. Through acquiring the real world data measures, our approach aims to accurately realize the spatial relationship of such layout elements. In particular, this solution is tremendously useful for mobile robotics relative localization, geo-location dynamic data manage- ment platforms, wireless sensor networking, smart routing, and so forth. In this research, we employ chirp spread spectrum modulation enabled radio transceivers for proximity measurement of the network nodes as the bidirectional weight in- formation of the graph edges. Physical link experiments confirm that this recent technology is adequately reliable against environmental distortions when employed for asynchronous round trip time of flight measurements. In order to achieve the best affordable accuracy and reach a high level of robustness against the esti- mation noise, the multidimensional scaling method is utilized. Implementation phase's outcome is a cooperative and proprioceptive self-constructive infrastruc- ture, for a flexible any-time localization application. Indoor and outdoor inves- tigations considering also the non line of sight conditions, provide the approach with an adaptive model to overcome the non Gaussian inevitable estimation error influences. In addition, based on the realistic model of the wireless links, scala- bility of the approach is investigated for larger logical and physical network sizes with a high likelihood of unambiguous realization throughout high fidelity simula- tions. Mobility of the topology is also considered in a developed motion estimation model, which enhances the accuracy and time complexity, and leads to a strategic movement management design. The solution shows promising robustness against communication corruption, environmental distortion and network nodes variant densities. Acknowledgements My sincerest moral appreciation first of all goes to Klaus J. Jacobs (1936-2008), whom his generosity was vital soul to keep the research goal and productivity of the Jacobs University alive. His name, role, and contribution will be always alive. Throughout finalizing this Thesis, there have been some very special people who have inspired, guided and supported me in various ways and so deserve mention and credit. In particular, I am honestly grateful to my supervisor Prof. Dr. Andreas Birk for his very insightful and encouraging comments and suggestions on this work, for our long discussions at the beginning of the project right through the end. Freedom, independency and self confidence he always inducted into my academic and research career, offered me an incredible atmosphere for development. My work and accomplishments were significantly possible because of his help and encouragements, and for letting me implementing and experiencing my ideas. I feel debt not to deeply appreciate the Jacobs University's generous scholarship during my studies, as well as the European Space Agency for partially funding my research. I also owe a great gratitude to the dissertation committee members; Prof. Dr. J¨urgenSch¨onw¨alderand Dr. Holger Kenn for their engagement, support and contribution. I am not forgetting the special moments that they played as a model for me during the past years, giving me a different sight of understanding, wether working or for my personal life. I want to take the opportunity to express my gratitude to all professors of the Smart Systems program at Jacobs University Bremen, whom continuously had a constructive contribution in my higher education. Very special thanks have go to my colleagues at the Robotics Research Group at Jacobs University Bremen for their inspiring and essential assistance and most importantly, friendship. And ... my beloved ones and the nicest friends, whom I can not even count. You made my life joyful, and gave me the great feeling of being active, energetic and not lonely. At the department, I am not forgetting Ms. Sigrid Manss for not hesitating any slight help I needed, as well as Ms. Marta M¨ullerfor her kindest supports. And indeed, I would love to show my feelings for the most memorable three persons who were there for me, always, in all moments of personal or professional frustrations; Dr. Anke-Maria Allner, Dr. Svenja Frischholz and Ms. Rosario Santos. I am sending very special and emotional appreciation to my uncles' families, whom were like my parents here. Without them and their moral support, my life could not have been as easy. At last but not the least, I am wordless to express my deep feelings and love for my unique parents and brothers. I could not have reached where I am today without having them, their continual encouragement, true support in any of my endeavors, and reminding me always the most beautiful meanings of life. iv Contents Declaration of Authorshipi Abstract iii Acknowledgements iv Nomenclaturex Acronyms xiv 1 Introduction2 1.1 Motivation and Background......................2 1.2 Objectives of the Research.......................7 1.3 Organization of this Dissertation................... 10 2 Positioning 13 2.1 Mobile Robotics Perspective...................... 14 2.2 RF Networks Perspective........................ 18 2.2.1 Wireless Media......................... 18 2.2.2 Infrastructure Principles.................... 26 3 Ranging and Cooperation 31 3.1 Ranging Categories........................... 32 3.2 Synchronous Resolution........................ 35 3.3 Networked Robots........................... 36 3.4 Networked Nodes............................ 38 3.5 Network Layout............................. 39 4 RSS Techniques in WLAN 43 4.1 Properties................................ 44 4.2 Techniques................................ 47 v Contents vi 4.3 Evaluation................................ 49 5 Problem Formulation 58 5.1 Coordinates............................... 59 5.2 Graph Theory.............................. 62 5.3 Spatial Realization........................... 65 5.3.1 Basics of classical MDS..................... 67 5.3.2 Computing distances using matrix algebra.......... 68 5.3.3 Finding the coordinates.................... 69 5.3.4 Coordinate system fitting................... 70 6 Wireless Link Characteristics 74 6.1 CSS Modulation............................. 75 6.2 Hardware................................ 77 6.3 Link's Statistical Properties...................... 78 6.3.1 Raw euclidean data......................
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