Etude de la Performance du Contrôle Autonome d'Intégrité pour les Approches à Guidage Vertical Performance of Receiver Autonomous Integrity Monitoring (RAIM) for Vertically Guided Approaches

Walter Todd

Description

Niveau: Supérieur, Doctorat, Bac+8
THÈSE En vue de l'obtention du DOCTORAT DE L'UNIVERSITÉ DE TOULOUSE Délivré par l'Institut National Polytechnique de Toulouse Discipline ou spécialité : Signal, Image, Acoustique JURY Professeur Francis Castanié Professeur Penina Axelrad Professeur Igor Nikiforov Docteur Todd Walter Docteur Audrey Giremus Docteur Christophe Macabiau Ecole doctorale : Mathématiques, Informatique et Télécommunications de Toulouse Unité de recherche : Laboratoire de Traitement du Signal et des Télécommunications de l'Ecole Nationale de l'Aviation Civile Directeur(s) de Thèse : Christophe Macabiau et Igor Nikiforov Rapporteurs : Penina Axelrad, Todd Walter et Audrey Giremus Présentée et soutenue par Anaïs Martineau Le 14 Novembre 2008 Titre : Etude de la Performance du Contrôle Autonome d'Intégrité pour les Approches à Guidage Vertical Performance of Receiver Autonomous Integrity Monitoring (RAIM) for Vertically Guided Approaches

• télécommunications de toulouse


• l?ecole nationale de l?aviation civile


• european satellite


• global positioning


• castanié professeur


• satellite constellations


• professeur igor


• président prof

Sujets

• The Songs Lennon and McCartney Gave Away
• Université de Toulouse
• Martineau
• École nationale de l'aviation civile

Informations

• Publié par: profil-zyak-2012
• Publié le: 01 novembre 2008
• Nombre de lectures: 73
• Langue: Français
• Poids de l'ouvrage: 3 Mo

Extrait

THÈSE


En vue de l'obtention du

DOCTORAT DE L’UNIVERSITÉ DE TOULOUSE DOCTORAT DE L’UNIVERSITÉ DE TOULOUSE

Délivré par l'Institut National Polytechnique de Toulouse
Discipline ou spécialité : Signal, Image, Acoustique


Présentée et soutenue par Anaïs Martineau
Le 14 Novembre 2008

Titre :

Etude de la Performance du Contrôle Autonome d’Intégrité
pour les Approches à Guidage Vertical

Performance of Receiver Autonomous Integrity Monitoring (RAIM)
for Vertically Guided Approaches

JURY

Professeur Francis Castanié
Professeur Penina Axelrad
Professeur Igor Nikiforov
Docteur Todd Walter
Docteur Audrey Giremus
Docteur Christophe Macabiau

Ecole doctorale : Mathématiques, Informatique et Télécommunications de Toulouse
Unité de recherche : Laboratoire de Traitement du Signal et des Télécommunications
de l’Ecole Nationale de l’Aviation Civile
Directeur(s) de Thèse : Christophe Macabiau et Igor Nikiforov
Rapporteurs : Penina Axelrad, Todd Walter et Audrey Giremus



THESE

en vue
de l‟obtention du


DOCTORAT DE L‟UNIVERSITE DE TOULOUSE

délivré par
l‟Institut National Polytechnique de Toulouse

Ecole Doctorale Mathématique Informatique et Télécommunication

Spécialité Signal, Image et Acoustique

par

Anaïs Martineau


Etude de la Performance du Contrôle Autonome d‟Intégrité
pour les Approches à Guidage Vertical


Performance of Receiver Autonomous Integrity Monitoring (RAIM)
for Vertically Guided Approaches


Soutenue le 14 Novembre 2008 à l‟Ecole Nationale de l‟Aviation Civile (ENAC) devant le
jury composé de :


Prof. Dr Francis Castanié Président
Prof. Dr Penina Axelrad Rapporteur
Dr Todd Walter Raur
Dr Audrey Giremus Rapporteur
Dr Christophe Macabiau Directeur de thèse
Prof Dr Igor Nikiforov Directeur de


Thèse préparée au Laboratoire de Traitement du Signal et des Télécommunications
de l‟Ecole Nationale de l‟Aviation Civile





Abstract


The International Civil Aviation Organization (ICAO) has recognized the Global Navigation
Satellite System (GNSS) as a key element of the Communications, Navigation, and
Surveillance / Air Traffic Management (CNS/ATM) systems as well as a foundation upon
which States can deliver improved aeronautical navigation services. But civil aviation
requirements can be very stringent and up to now, the bare systems cannot alone be used as a
means of navigation. Therefore, in order to ensure the levels required in terms of accuracy,
integrity, continuity of service and availability, ICAO standards define different architectures
to augment the basic constellations. Some of them use control stations to monitor satellite
signals and provide corrections, others only use measurement redundancy. This study focuses
on this last type of augmentation system and more particularly on Receiver Autonomous
Integrity Monitoring (RAIM) techniques and performance.

RAIM is currently a simple and efficient solution to check the integrity of GNSS down to
Non Precision Approaches. But the future introduction of new satellite constellations such as
the European satellite navigation system Galileo or modernized Global Positioning System
(GPS) will imply great improvements in the number as well as the quality of available
measurements. Thus, more demanding phases of flight such as APproaches with Vertical
guidance could be targeted using RAIM to provide integrity monitoring. This would result in
some interesting safety, operational and environmental benefits. This Ph.D. evaluates the
potential capacity of RAIM algorithms to support approach and landing phases of flight with
vertical guidance.

A thorough bibliographic study of civil aviation requirements is first presented; some
candidate LPV200 signal in space performance requirements not yet included in the ICAO
standards are also provided.

To evaluate GNSS positioning performance, pseudorange measurements have to be modeled
as precisely as possible and especially the different errors that affect them. The main sources
of error are signal propagation delays caused by the ionosphere and the troposphere, space
vehicle clock error, satellite position estimation error, multipath, receiver errors which main
source is code tracking loop noise. Thus, these errors can be due to the space segment, the
control segment or the user segment. Systematic errors are gathered in the fault free case
measurement model; unusual errors, that may cause a dangerous positioning failure and that
may have to be detected, are gathered in the faulty case measurement model. Finally, a
complete model of pseudo range measurements, including interference effects and satellite
failures, is given. A special attention is put on the User Equivalent Range Error (UERE)
variance computation. Indeed, among all input parameters of RAIM availability simulator,
UERE has, by far, the most significant impact on the estimated availability.

Three distinct classes of RAIM algorithms are studied in this thesis. The Least Square
Residual method in which the sum of the squares of the pseudorange residuals plays the role
of the basic observable is first recalled. The Maximum Solution Separation method which is
3
Abstract
based on the observation of the separation between the position estimate generated by a full-
set filter (using all the satellite measurements) and the position estimate generated by each
one of the subset filters (each using all but one of the satellite measurements) is then
discussed and an improved way of computing the associated protection level is proposed.
Finally, a new promising method based on the Generalized Likelihood Ratio test is presented
and several implementations are described.

The way these different methods are implemented to take into account both civil aviation
requirements and threat model is then detailed. In particular some methods to obtain the inner
probability values that RAIM algorithms need to use are presented. Indeed, high level
requirements interpretation for RAIM design is not clearly standardized.

Finally simulations results are presented. They permit to evaluate RAIM ability to provide
integrity monitoring for approaches with vertical guidance operations considering various
scenarios.

The main contributions of this thesis are a detailed computation of user equivalent range error
variance, an analysis of the effect of interferences on pseudorange measurement, an
adaptation of LSR RAIM algorithm to nominal biases, an improvement of MSS protection
levels computation, the implementation of GLR algorithm as a RAIM including the
computation of an analytical expression of the threshold that satisfies the false alarm
probability and the prediction of the probability of missed detection, design of a sequential
GLR algorithm to detect step plus ramp failure and an analysis of the amplitude of smallest
single biases that lead to a positioning failure.

Least Squared Residual, Maximum Solution Separation and constrained Generalized
Likelihood Ratio RAIM availabilities have been computed for APVI and LPV200 approaches
using both GPS L1/L5 and Galileo E1/E5b pseudorange measurements. It appears that both
APV I and LPV200 (VAL=35m) operations are available using GPS/Galileo + RAIM to
provide integrity as an availability of 100 % has been obtained for the detection function of
the three studied algorithms. An availability of 100 % has also been obtained for the LSR
exclusion function. On the contrary, LSR RAIM FDE availabilities seem not sufficient to
have Galileo + RAIM or GPS +RAIM as a sole means of navigation for vertically guided
approaches.


4

Résumé


L‟Organisation de l‟Aviation Civile Internationale (OACI) a reconnu la navigation par
satellite, Global Navigation Satellite System (GNSS), comme un élément clé des systèmes
CNS/ATM (Communications, Navigation, and Surveillance / Air Traffic Management) et
comme une base sur laquelle les Etats peuvent s‟appuyer afin de délivrer des services de
navigation aérienne performants.

Mais l‟utilisation des systèmes de navigation par satellites pour des applications de type
aviation civile ne va pas sans répondre à des exigences en terme de précision, de continuité,
d‟intégrité et de disponibilité. Ces exigences opérationnelles liées aux différentes phases de
vol requièrent pour les systèmes GNSS l‟appui de moyens d‟augmentation tels ceux utilisant
des stations de surveillance sol