ION GNSS+ Tutorials

ION GNSS+ pre-conference tutorials have been organized to provide in-depth learning of specific GNSS-related disciplines and will be taught in a classroom setting. Course notes will be provided to registered attendees via a link provided for advance download.

In-Person Attendance: For those attending the conference in-person, AC power will not be made available for individual laptop computers; please come prepared with adequate battery power if required. It is recommended that attendees dress in layers to accommodate varying temperatures in the classroom.

Virtual Learning: The course will be recorded. Registered students may view the recorded course one time within 30 days. The recording will be made available to eligible tutorial registrants 24 hours after the course's conclusion. Those viewing the recording will not have real-time access to instructor(s) for live chat or question and answer. Note that the virtual learning option allows you to register for tutorials scheduled at the same time.

Tutorial Costs and Registration:
$450 per course if registered and paid by August 11
$500 per course if payment is received after August 11

Register using the ION GNSS+ Registration Form (see the registration page for additional information and policies). ION reserves the right to cancel a tutorial. If cancelled, the full cost of the course will be refunded via the original payment method.

Tuesday, September 12: 9:00 a.m. - 12:30 p.m.
Multi-constellation GNSS Signals and Systems ( Video Preview)	Dr. Chris G. Bartone, P.E.
GNSS Integrity ( Video Preview)	Dr. Mathieu Joerger
Factor Graphs ( Video Preview)	Dr. Ryan Watson / Dr. Clark Taylor
Tuesday, September 12: 1:30 p.m. - 5:00 p.m.
GNSS in the National Airspace	Dr. Todd Walter
PNT for sUAVs	Dr. Robert Leishman
Introduction to Cryptography with Navigation	Dr. Joe J. Rushanan

Multi-constellation GNSS Signals and Systems

Date/Time: Tuesday, September 12, 9:00 a.m. - 12:30 p.m. MDT
Recording: Course registrants who do not attend the live course in-person may view a recording of the course one time within 30 days.
Room: Granite (Third Floor)

Registration fee:
$450 if registered and paid by August 11
$500 if payment is received after August 11

Course Level: Beginner

This course emphasizes the fundamentals of multi-constellation GNSS. The course begins with an overview of GNSS followed by presentations on each of the GNSSs in operation and/or development today. The course will highlight common features of the various GNSSs and point out key differences between them. Topics to be covered include:

GNSS segments; space, ground, user segments
GNSS link budget
Fundamental concept of GNSS position and time determination
GNSS coordinate frames, datums and time
GNSS signal structure formats: carrier, code, data
- Direct sequence spread spectrum; auto and cross correlation
GNSS antenna & receiver technologies - overview
GPS Legacy: C/A, P(Y) code and NAV formats
GPS Modernized: L2C, L5, L1C, CNAV and CNAV-2 formats
GLONASS
- GLONASS SV versions
- Legacy C/A, P codes and FDMA signals
- Modernized CDMA codes and frequencies
Galileo, E1, E6/E6P, E5a, E5b, AltBOC, SAR Codes, frequencies and data formats
BeiDou, BDS I, BDS II, BDS III, B1, B2, B3 signals and formats
SBAS used throughout the globe
QZSS, L1, L2, L5, L6 signals, codes and services
NAViC: L5, S band signals, message types
GNSS corrections for clock, code, atmospheric, transit time, etc.
GNSS user solutions

Dr. Chris G. Bartone, P.E., is a professor at Ohio University with over 35 years of professional experience and is an ION Fellow. He received his Ph.D.EE from Ohio University, a M.S.EE from the Naval Postgraduate School, and B.S.EE from Penn State. Dr. Bartone has developed and teaches a number of GPS, radar, wave propagation and antenna classes. His research concentrates on all aspects of navigation.

GNSS Integrity

Registration fee:
$450 if registered and paid by August 11
$500 if payment is received after August 11

Course Level: Intermediate

This course will describe (Part 1) fundamental concepts in GNSS integrity, (Part 2) successful implementations in aviation applications, and (Part 3) major challenges in future autonomous navigation for air, ground, and sea transportation. This year’s version of the course will emphasize Receiver Autonomous Integrity Monitoring (RAIM); it will include a handout on RAIM theory and a set of problems with solutions and MATLAB codes.

In Part 1, we will define navigation safety metrics and requirement parameters including integrity and continuity risks, alert limit, time to alert, and exposure period. We will identify the three major over-bounding methods used to derive high-integrity signal-in-space error models. We will show the impact a GNSS fault such as, for example, an excessive satellite clock drift. We will outline how integrity-monitoring responsibilities can be allocated between reference and user receivers and how prior probabilities of satellite faults are evaluated.

In Part 2, we will briefly describe the major implementations used in aviation applications: the Ground-Based Augmentation Systems (GBAS), the Space-Based Augmentation Systems (SBAS) and the Aircraft-Based Augmentation System (ABAS). We will focus on RAIM and Advanced RAIM; we will use graphical tools of failure mode curves and parity space representations to identify differences between solution separation and chi-squared approaches. We will show recent developments in ARAIM intended to optimize ARAIM integrity and continuity monitoring performance while limiting computational load.

In Part 3, we will review recent efforts in standard developments and performance evaluations to achieve safe navigation in aviation, maritime, railway, and automotive applications. We will discuss recent research on robust modeling of measurement error time correlation that enables high-integrity Kalman filtering of combined GNSS and inertial data. We will identify major challenges in implementing precise point positioning (PPP) and real time kinematic (RTK) to simultaneously achieve high accuracy and high integrity.

Dr. Mathieu Joerger is an assistant professor at Virginia Tech, recipient of ION’s Parkinson Award (2009) and Early Achievement Award (2014). He is the senior editor on Navigation for IEEE TAES and a member of EU/US ARAIM Working-Group-C and of RTCM’s Integrity Monitoring for High Precision Applications (SC-134). He received his PhD from Illinois Institute of Technology.

Factor Graphs

Registration fee:
$450 if registered and paid by August 11
$500 if payment is received after August 11

Course Level: Intermediate (attendees should have an introductory knowledge of filtering)

While the Kalman Filter (KF) family (linear KF, EKF, UKF, etc.) has been the workhorse of navigation systems for several decades, the factor graph is a generalization of the Kalman Filter that offers improved performance for non-linear systems and is more easily applied to complex systems. The goal of this tutorial is to take a practitioner who is familiar with the Extended Kalman filter and introduce them to factor graphs. By the end of the tutorial, the attendants should be able to create a simple factor graph system and will have been exposed to some of the more advanced concepts that make factor graphs an exceptional choice for navigation problems.

More specifically, this tutorial will introduce the factor graph representation of dynamic systems and how this representation is equivalent to a weighted least squares problem that can be solved with sparse matrix computational tools. We will demonstrate the (surprisingly low) computational costs of factor graphs and methods used to keep those costs low. We will also introduce popular software packages that can be used to solve factor graph problems, including GTSAM. Complex estimation problems that can be difficult to handle with other estimation frameworks will be introduced in the factor graph framework and example solutions to these problems will be demonstrated.

Dr. Ryan Watson currently works at Xona Space Systems enabling integrity for their LEO satellite navigation constellation. He previously worked at the NASA Jet Propulsion Laboratory and the Johns Hopkins University Applied Physics Laboratory on problems related to state estimation/data fusion for robotic and space missions. He holds a PhD from West Virginia University.

Dr. Clark Taylor is an assistant professor in the ANT Center at the Air Force Institute of Technology. He received his PhD from University of California, San Diego, and previously worked as a senior research engineer with the Air Force Research Laboratory and an assistant professor in electrical engineering at Brigham Young University.

GNSS in the National Airspace

Date/Time: Tuesday, September 12, 1:30 p.m. - 5:00 p.m. MDT
Recording: Course registrants who do not attend the live course in-person may view a recording of the course one time within 30 days.
Room: Granite (Third Floor)

Registration fee:
$450 if registered and paid by August 11
$500 if payment is received after August 11

Course Level: Beginner

This course will describe the use of the Global Navigation Satellite System (GNSS) to support air navigation. Particular attention will be paid to challenges that can affect the availability and safety of GNSS based navigation. The currently operating systems that augment the Global Positioning System (GPS) will be described. These are Aircraft Based Augmentation Systems (ABAS), Ground Based Augmentation Systems (GBAS), and Satellite Based Augmentation Systems (SBAS). They support differing flight operations and different levels of operations. Each method is described in detail and how it overcomes the challenges to provide suitable guidance.

The main challenges that must be overcome are satellite faults, ionospheric effects, tropospheric effects, local reflections of the signals at the aircraft, and radio frequency interference. This course will describe each effect in detail and how they are addressed. Aircraft navigation is judged by four criteria: accuracy, integrity, continuity, and availability. How well each system performs on these metrics will be described. The course will also describe how these systems have been and are being integrated into the national airspace. The course will conclude with a discussion on the future direction of these augmentation systems utilizing new signals and new GNSS constellations.

This course is suitable for all interested parties who have at least an introductory knowledge of satellite navigation. A brief review of the elements of GNSS most relevant to augmentation systems will be provided. No previous knowledge of differential GNSS, augmentation systems, or integrity algorithms is needed.

Dr. Todd Walter received his Ph.D. in Applied Physics from Stanford University. He is a research professor in the Department of Aeronautics and Astronautics at Stanford University. His research focuses on implementing high-integrity air navigation systems. He has received the ION’s Thurlow and Kepler awards. He is an ION Fellow and past president.

PNT for sUAVs

Registration fee:
$450 if registered and paid by August 11
$500 if payment is received after August 11

Course Level: Beginner to Intermediate

Small Unmanned Aerial Vehicles (sUAVs) are becoming increasingly ubiquitous. While their utilization may not have quite hit projections offered by venture capitalists over the last decade, these vehicles have found utility and have been incorporated into products in a wide variety of ways, for example: remote-control flying, photography and videography, infrastructure/agriculture/construction site inspection, product/medical delivery, racing, mapping, intelligence, surveillance and reconnaissance (ISR), and defense.

sUAVs have been and will continue to be fantastic platforms for enabling research in GNC, PNT, and many other disciplines. A key reason is that sUAVs offer the unique constraint of coupling low size, weight, and power (SWAP) with a critical need for urgency and timeliness of PNT and control information. This class will review the consequences of this unique constraint and the influences on both sensors and algorithms.

This course is a hands-on introduction and review of PNT for sUAVs and will provide in-depth information on current sensors, autopilots, software architectures, and algorithms for PNT. One key algorithm for navigation for sUAVs has been visual-inertial odometry (VIO). This modality, often enabled by machine learning approaches, has been optimized to strike the unique balanced required for the SWAP-timeliness constraint mentioned. This class will provide a hands-on, deeper dive into VIO methods and provide python examples to promote further understanding.

This course is applicable for those wanting to utilize UAVs for research, as well as those desiring to better understand the current state of the art in PNT for sUAVs. Pre-requisites and equipment: a basic understanding of PNT topics, including estimation and sensor fusion and object-oriented programming and Python programming language familiarity for the VIO software projects. Attendees will need their own charged laptops if they want to work on the projects in-class. Relevant course materials/notes and software examples are provided to registered attendees in advance.

Dr. Robert Leishman Dr. Rob Leishman is currently the PNT area lead with Draper. Formerly, he was director of the Autonomy and Navigation Technology (ANT) Center at the Air Force Institute of Technology. There Dr. Leishman led a team of researchers and students in developing cutting-edge, defense-focused autonomy and navigation technologies, primarily for sUAVs.

Introduction to Cryptography with Navigation

Registration fee:
$450 if registered and paid by August 11
$500 if payment is received after August 11

Course Level: Beginner

This tutorial offers a brief, broad, and benign overview of cryptography. We will begin with the three main cryptographic methods: symmetric ciphers, hashes, and public key cryptography. These methods will be illustrated using a variety of non-navigation examples, along with a discussion of how to implement them in practice, such as using OpenSSL. We will describe the necessary enablers of cryptography, such as key management. Finally, we will show the various places cryptography is used in navigation applications, including current implementations.

Dr. Joe J. Rushanan is a principal mathematician in the Communications, SIGINT, & PNT department of The MITRE Corporation. He was part of the M-code signal design and the L1C signal design teams and was the 2019 recipient of ION’s Capt. P.V.H. Weems award for his sustained contributions to the design on GPS. Additionally, he currently teaches cryptography for Northeastern University’s Khoury College Cybersecurity graduate program. He received his BS/MS and PhD in mathematics respectively from The Ohio State University and the California Institute of Technology.

ION GNSS+ 2023
September 11-15
Tutorials: Sept. 12
Denver, CO

ION GNSS+ Tutorials