Thèse de l'Institut National Polytechnique de Toulouse INPT n°

Fabrice Legrand

Description

Niveau: Supérieur, Doctorat, Bac+8
Thèse de l'Institut National Polytechnique de Toulouse (INPT) – n° 1917 Présentée à l'ENAC de Toulouse, le 15 Novembre 2002 par Fabrice LEGRAND MODELES DE BOUCLE DE POURSUITE DE SIGNAUX A SPECTRE ETALE ET METHODE D'AMELIORATION DE LA PRECISION DES MESURES BRUTES Membres du jury : Prof. Dr. Tony PRATT, (rapporteur) Directeur technique GPS chez Parthus Ltd, Northampton, England M. Jean-Luc ISSLER, (directeur) Chef du département Radionavigation du CNES, Toulouse, France Prof. Dr. Francis CASTANIE, (président du jury) Directeur du laboratoire TéSA, Toulouse, France Prof. Dr. Bernd EISSFELLER, (rapporteur) Institut de Géodésie et de Navigation, University of the Federal Armed Forces, Munich, Germany Dr. Dennis AKOS, (rapporteur) Chercheur associé, Stanford University GPS Lab, Stanford, USA Dr. Christophe MACABIAU, (directeur) Chef du laboratoire CNS de l'ENAC, Toulouse, France Version finale du rapport – Janvier 2005

• gps lab


• research associate


• radionavigation department


• cns research


• methode d'amelioration de la precision


• chef du département radionavigation du cnes

Sujets

• Spread
• Institut national polytechnique de Toulouse
• Legrand
• Stanford University

Informations

• Publié par: profil-zyak-2012
• Nombre de lectures: 206
• Langue: Français
• Poids de l'ouvrage: 5 Mo

Extrait

Thèse de l’Institut National Polytechnique de Toulouse (INPT) – n° 1917 Présentée à l’ENAC de Toulouse, le 15 Novembre 2002 par Fabrice LEGRAND MODELES DE BOUCLE DE POURSUITE DE SIGNAUX A SPECTRE ETALE ET METHODE D’AMELIORATION DE LA PRECISION DES MESURES BRUTES Membres du jury : Prof. Dr. Tony PRATT, (rapporteur) Directeur technique GPS chez Parthus Ltd, Northampton, England M. Jean-Luc ISSLER, (directeur) Chef du département Radionavigation du CNES, Toulouse, France Prof. Dr. Francis CASTANIE, (président du jury) Directeur du laboratoire TéSA, Toulouse, France Prof. Dr. Bernd EISSFELLER, (rapporteur) Institut de Géodésie et de Navigation, University of the Federal Armed Forces, Munich, Germany Dr. Dennis AKOS, (rapporteur) Chercheur associé, Stanford University GPS Lab, Stanford, USA Dr. Christophe MACABIAU, (directeur) Chef du laboratoire CNS de l’ENAC, Toulouse, France Version finale du rapport – Janvier 2005

Thesis of the Institut National Polytechnique de Toulouse (INPT), France Presented at ENAC, Toulouse, France, on November 15, 2002 by Fabrice LEGRAND SPREAD SPECTRUM SIGNAL TRACKING LOOP MODELS AND RAW MEASUREMENTS ACCURACY IMPROVEMENT METHOD Examining board: Prof. Dr. Tony PRATT, (thesis reviewer) GPS Technical Director at Parthus Ltd, Northampton, England Mr. Jean-Luc ISSLER, (thesis supervisor) Head of the Radionavigation department of the CNES, Toulouse, France Prof. Dr. Francis CASTANIE, Director of the TéSA Laboratory, Toulouse, France Prof. Dr. Bernd EISSFELLER, (thesis reviewer) Institute of Geodesy and Navigation at the University of the Federal Armed Forces, Munich, Germany Dr. Dennis AKOS, (thesis reviewer) Research associate with the Stanford University GPS Lab, Stanford, USA Dr. Christophe MACABIAU, (thesis supervisor) Head of the CNS Research Laboratory of the ENAC, Toulouse, France Final version of the report – January 2005

Avant-propos

Etant donné que les rapporteurs de cette thèse sont non-francophones, le manuscrit est rédigé en anglais. Néanmoins, l’introduction, la conclusion, la table des matières ainsi que le résumé des chapitres sont rédigés en français.

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Acknowledgments

Author wish to thank the CENTRE NATIONAL D’ETUDES SPATIALES (CNES, theFrench Space Agency) and ALCATEL SPACE INDUSTRIES (ASPI) for having supported this research, and the ECOLE NATIONALE DE L’AVIATION CIVILE (ENAC, theCivil Aviation School French ) for having provided accommodations during these years of work. I specially wish to thank my thesis supervisors M. Christophe MACABIAU and M. Abdelahad BENHALLAM from the ENAC, M. Jean-Luc ISSLER and M. Laurent LESTARQUIT from CNES, M. Christian MEHLEN from ASPI for having put trust in me and given lots of their time to support and help me. I also wish to thank M. Eric CHATRE, M. Jean-Marc LISEZ and M. Cyril DUPOUY from STNA for having provided technical assistance. Thanks to the students, the trainees and the staffs of the ENAC, and of course to my family and friends for their support and help.

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Contents

Avant-propos...............................................................................................................................................................................5 Acknowledgments.......................................................................................................................................................................7 Contents ......................................................................................................................................................................................9 Tables des matières ...................................................................................................................................................................13

INTRODUCTION .................................................................................................................. 17

Introduction ...............................................................................................................................................................................19

CHAPTER I : RANGE MEASUREMENTS ON SPREAD SPECTRUM SIGNALS..... 21

Chapitre I : Mesures de distance sur les signaux à spectre étalé................................................................................................21 I.1INTRODUCTION AND DEFINITIONS ABOUT PSEUDORANGE AND RAW PHASE MEASUREMENTS .............................................................................................................................................22 I.1.1D EFINITION OF THE PSEUDORANGE ...............................................................................2.2................ I.1.1.1R ANGE AND PSEUDORANGE .........................2.....................................................................................2 I.1.1.2E RRORS ON MEASURED PSEUDORANGE ........................................................................................23.... I.1.2I NTRODUCTION ON THE PSEUDORANGE MEASUREMENT TECHNIQUE ...........................................25 I.1.2.1P SEUDORANGE INFORMATION EXTRACTION .......2........6...................................................................... I.1.2.2I NTRODUCTION ON RECEIVER ARCHITECTURE ..................................................................................26 I.2MODEL AND PROPERTIES OF GNSS SPREAD SPECTRUM SIGNALS ...............................28 I.2.1M ODEL OF A RECEIVED SIGNAL ................28...................................................................................... I.2.1.1G ENERAL EXPRESSION ..................................28................................................................................... I.2.1.2D YNAMICS MODEL .................................................................29.......................................................... I.2.1.3C ARRIER TO NOISE RATIO .............................................31.................................................................... I.2.2S IGNAL PROPERTIES ..........................................31.............................................................................. I.2.2.1I NSTANTANEOUS CARRIER FREQUENCY AND D OPPLER FREQUENCY SHIFT .......................................31 I.2.2.2A UTOCORRELATION FUNCTION OF SPREADING SIGNALS ...................................................................32 I.2.2.3C ROSS CORRELATION FUNCTION OF SPREADING SIGNALS .................................................................33 I.2.2.4P OWER SPECTRAL DENSITY ................34.............................................................................................. Appendix of Chapter I...............................................................................................................................................................37 Appendix I-1: Maximal length sequences and Gold codes........................................................................................................39 Appendix I-2: Correlation functions of a PRN signal based on Gold codes..............................................................................41

CHAPTER II : SEQUENTIAL MODELS OF DIGITAL TRACKING LOOPS ............ 45

Chapitre II : Modèles séquentiels des boucles de poursuite numériques ...................................................................................45 II.1CARRIER PHASE TRACKING WITH COSTAS LOOP..............................................................46 II.1.1M IXING WITH THE LOCAL SIGNALS / IQ DECOMPOSITION ............................................................47 II.1.2P REDETECTION FILTERING .............................................................................................47................ II.1.3P HASE DISCRIMINATORS ................................52................................................................................. II.1.4L OOP FILTERING .............................................................................................................................53 II.1.5L OCAL SIGNALS GENERATION ....................................5...........................4......................................... II.1.6D ATA DEMODULATION ................................................................................55....................................

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II.2 II.2.1 II.2.2 II.2.3 II.2.4 II.3

CODE TRACKING WITH DELAY LOCK LOOPS ......................................................................57 C ODE CORRELATORS ..........................................85............................................................................ C ODE PHASE DISCRIMINATORS 95....................................................................................................... L OOP FILTERING ..16........................................................................................................................... L OCAL CODE GENERATION ................................................................1.6............................................ SIMULTANEOUS CODE AND CARRIER PHASE TRACKING LOCK LOOPS.....................63

II.4GAUSSIAN NOISE IN THE LOOPS ...............................................................................................64 II.4.1RF FILTERING EFFECT ..........................................64.......................................................................... II.4.2I N - PHASE AND QUADRATE BASEBAND NOISES .................................................................................65 II.4.3C ORRELATOR OUTPUT NOISES ........................................................................66................................ Appendix of Chapter II .............................................................................................................................................................67 Appendix II-1: Series expansions of sine and cosine functions.................................................................................................69 Appendix II-2: Gaussian noise in the loops...............................................................................................................................73

CHAPTER III : SAMPLED PHASE PROPAGATION MODELS .................................. 79

Chapitre III : Modèles discrets de propagation de la phase .......................................................................................................79 III.1TRADITIONAL DIGITAL CONSTANT-RATE MODEL ............................................................80 III.1.1G ENERIC CLOSED LOOP MODEL 80...................................................................................................... III.1.1.1M ODEL OF THE DISCRIMINATOR ................80....................................................................................... III.1.1.1.1................................................................................................ericnonGenomed.l..l-niaer........80...................... III.1.1.1.2Linear model ....................................................................................................................................................81 III.1.1.2D IGITAL LOOP FILTER .......................................................18................................................................ III.1.1.3NCO MODEL ....................................................18................................................................................ III.1.2L INEAR CLOSED LOOP MODEL .......................................2.8................................................................ III.1.3L INEAR TRANSFER FUNCTIONS .......................................83................................................................ III.2PROPOSED MULTI-RATE MODEL INCLUDING INTEGRATE & DUMP PREDETECTION FILTERS..............................................................................................................................85 III.2.1D ESCRIPTION OF THE MODEL .........................................................................................85................ III.2.1.1G ENERIC CLOSED LOOP MODEL ........................................................................................58................ III.2.1.2M ODEL OF THE DISCRIMINATOR INCLUDING THE I&D PREDETECTION FILTERS ................................85 III.2.1.3M ODEL OF THE NCO WITH A HELD COMMAND SIGNAL ....................................................................86 III.2.1.4C LOSED LOOP MODEL ......................................................................................................................68. III.2.1.5 L INEAR TRANSFER FUNCTIONS AS A FUNCTION OF THE LOOP FILTER ORDER ....................................89 III.2.1.6V ALIDATION OF THE NEW LINEAR MODEL .......................................................................9.1................ III.2.2E VALUATION OF THE TRACKING ERROR ................................................................95........................ III.2.2.1S ENSITIVITY ON NOISE ......9.........5....................................................................................................... III.2.2.1.1Phase noise model ............................................................................................................................................95 III.2.2.1.2Equivalent noise bandwidth of the loop ...........................................................................................................96 III.2.2.1.3Expression of the equivalent noise bandwidth as a function of the loop filter coefficients ..............................99 III.2.2.2S ENSITIVITY TO DYNAMICS ................................................10..3.......................................................... III.2.2.2.1Expression of the steady state error ................................................................................................................103 III.2.2.2.2Definition of the Steady State Error Factor ....................................................................................................105 III.2.2.3T OTAL TRACKING ERROR ..................................01....6......................................................................... Appendix of Chapter III ..........................................................................................................................................................109 Appendix III-1: Multi-rate linear model simplifications .........................................................................................................111 Appendix III-2: Loop filter coefficients expressed as a function of the poles of the loop transfer function – Usual digital constant rate model..................................................................................................................................................................115 th Appendix III-3: Equivalent initial value of themderivative of the averaged input phase.....................................................119 Appendix III-4: Generic Expressions of the linear transfer functions derived from the multi-rate model of loops.................121

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