Tuesday, September 20: 9:00 a.m. - 12:30 p.m.
Multi-constellation GNSS Signals and Systems ( Video Preview)	Dr. Chris G. Bartone, P.E.
Indoor Navigation and Positioning ( Video Preview)	Dr. Li-Ta Hsu
Ionospheric Effects, Monitoring, and Mitigation	Dr. Y. Jade Morton
Tuesday, September 20: 11:00 a.m. - 12:00 p.m.
Maximizing Your ION GNSS+ Presentation (Free!)	Dr. André Hauschild
Tuesday, September 20: 1:30 p.m. - 5:00 p.m.
Introduction to Multiband and Multi-Constellation Satnav Receivers using Python ( Video Preview)	Dr. Sanjeev Gunawardena / Mark Carroll
Factor Graphs ( Video Preview)	Dr. Ryan Watson / Dr. Clark Taylor
GNSS Integrity ( Video Preview)	Dr. Mathieu Joerger
GNSS in the National Airspace	Dr. Todd Walter

Multi-constellation GNSS Signals and Systems

Date/Time:
In-Person and Virtual Attendees: Tuesday, September 20, 9:00 a.m. - 12:30 p.m. MDT
Recording: Course registrants who do not attend the live course (either in-person or virtually) may view a recording of the course one time within 30 days.
Room: Capitol Ballroom 1 (Fourth Floor)

Registration fee:
$400 if registered and paid by August 19
$450 if payment is received after August 19

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 antenna & receiver technologies - overview
• GNSS signal structure formats: carrier, code, data
  • Direct sequence spread spectrum; auto and cross correlation
• GPS legacy and modernized signals:
• GPS SV blocks
• Legacy GPS: C/A, P(Y) code and NAV formats
• Modernized GPS: 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.

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Indoor Navigation and Positioning

Date/Time:
In-Person and Virtual Attendees: Tuesday, September 20, 9:00 a.m. - 12:30 p.m. MDT
Recording: Course registrants who do not attend the live course (either in-person or virtually) may view a recording of the course one time within 30 days.
Room: Mineral Hall DE (Third Floor)

Registration fee:
$400 if registered and paid by August 19
$450 if payment is received after August 19

Course Level: Beginner to Intermediate

This course will provide an overview of the Indoor Positioning and Indoor Navigation (IPIN) system. Starting from the markets and applications using IPIN, we will introduce the popular technologies and sensors related. Then, an IPIN framework will be introduced that consists of the source space, algorithm space, and integration. After introducing the single point positioning (SPP), we will discuss dead reckoning (DR).

Regarding the data sources of SPP, we separate the sources into homogeneous (geometry based) ones and heterogeneous (scene matching/analysis based) ones. The former ones contain the measurements model of RSS-ranging, AOA, TOA and TDOA while the latter ones contain the fingerprint and other transformed data sources that used to match with pre-surveyed databases. The error and limitation of the SPP will be discussed. The popular DR, using inertial, LIDAR, and visual sensors, namely PDR, LO, and VO, is also introduced before the sensor integration. Finally, the integration based on EKF and FGO is briefly introduced.

The course is suitable for the entry-level R&D students, researchers and engineers who will be working on the projects of IPIN. This course will also appeal to the managers and executives who wish to start a new project and application based on IPIN. The course will conclude with a discussion on the future direction of the indoor positioning system with the coming IoT and 5G era.

Dr. Li-Ta Hsu, born in Taiwan, is an associate professor in The Hong Kong Polytechnic University where he directs the Intelligent Positioning and Navigation Lab focused on the navigation for pedestrian and autonomous driving in urban canyons. His research interest is positioning in GNSS challenged environments.

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Ionospheric Effects, Monitoring, and Mitigation

Date/Time:
In-Person and Virtual Attendees: Tuesday, September 20, 9:00 a.m. - 12:30 p.m. MDT
Recording: Course registrants who do not attend the live course (either in-person or virtually) may view a recording of the course one time within 30 days.
Room: Agate (Third Floor)

Registration fee:
$400 if registered and paid by August 19
$450 if payment is received after August 19

Course Level: Beginner to Intermediate

Ionospheric effects are major threats to the availability, continuity, and accuracy of GNSS solutions. Models, global networks of GNSS stations, and LEO satellite-based radio occultation constellations have been established to monitor and predict the ionospheric effects.

This course will present an overview of the current state-of-art understanding of the various ionospheric effects on GNSS-based navigation systems and their mitigation techniques. The course consists of five parts. The first part is a review of the fundamental properties of the ionosphere that impact satellite navigation signals and PVT solutions. The second part discusses the ionospheric refractive effects, their contributions to the GNSS measurement model, Total Electron Content (TEC) estimation techniques and TEC products, higher order refraction errors, and refractive effect correction techniques. Part three covers the ionospheric scintillation effect, including a brief overview of radio wave propagation through the plasma irregularities, followed by climatology and morphology of scintillation occurrences, and the impact of scintillation on RTK and PPP systems. Part four takes a deeper look into GNSS receiver carrier tracking algorithms designed to combat ionospheric scintillation for ground- and LEO satellite-based receivers. Part five will provide an update on the latest development in space weather monitoring and forecasting using machine learning algorithms and worldwide GNSS observations. We will finish the course with an outlook for outstanding challenges in the field.

Dr. Jade Morton is an Aerospace Engineering professor at the University of Colorado, Boulder. Her research interests lie at the intersection of satellite navigation technologies and remote sensing of Earth’s ionosphere, atmosphere, and surface. She is a recipient of ION Thurlow, Burka, Kepler, and IEEE Kershner award and a Fellow of IEEE, ION, and RIN.

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Maximizing Your ION GNSS+ Presentation

Date/Time:
In-Person: Tuesday, September 20, 11:00 a.m. - 12:00 p.m. MDT
Recording: This course will not be live streamed. However, it will be recorded and made available for all attendees.
Room: Mineral Hall FG (Third Floor)

Presentations do not always come easily, so we invite you to attend our in-person instruction to learn how to maximize your 20-minute presentation time to ensure you deliver an informative and engaging presentation. General presentation delivery and chart presentation guidelines will be reviewed, as well as additional details specific to ION conferences. Don’t miss our exclusive tips and tricks to ensure success and opportunities to foster engagement with your professional peers and the rest of the PNT community.

This interactive course will be presented by Dr. André Hauschild, a scientific staff member with the German Aerospace Center (DLR). Dr. Hauschild has served as an ION program chair for both the ION GNSS+ and ION’s International Technical Meeting in the past as well as actively participating as a session chair, member of Council, and ION conference speaker on numerous occasions. He is the 2019 recipient of the Institute of Navigation’s Tycho Brahe Award.

To view a condensed video highlight of the course, visit https://www.ion.org/gnss/author-resource-center-presentation.cfm.

This course is provided complimentary to any registered conference attendee. Separate registration will not be required.

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Introduction to Multiband and Multi-Constellation Satnav Receivers using Python

Date/Time:
In-Person and Virtual Attendees: Tuesday, September 20, 1:30 p.m. - 5:00 p.m. MDT
Recording: Course registrants who do not attend the live course (either in-person or virtually) may view a recording of the course one time within 30 days.
Room: Agate (Third Floor)

Registration fee:
$400 if registered and paid by August 19
$450 if payment is received after August 19

Course Level: Beginner to Intermediate

Click here to view the paper referenced in this video abstract

This hands-on course aims to provide attendees with a solid understanding of the fundamentals of satellite timing and navigation (satnav) software receivers and associated signal processing. The course is divided into multiple modules, each comprised of a short lecture followed by the completion of a Python demo project that reinforces the concepts and techniques covered. By the end of the course, attendees will have an easy-to-use satnav software receiver running on their laptop that takes multiband live-sky sampled data files, acquires and tracks visible open satnav signals and outputs signal observables. This open-source Python code may be further extended to support numerous advanced research applications.

Topics covered:

• Overview of satnav bands, signal structures, link budget, and receiver architecture
• FFT-based signal acquisition engines
• Correlation across satellite-referenced time epochs on data referenced to receiver epochs: the split-sum correlator
• Carrier tracking loops: FLL, PLL and FLL-aided-PLL
• Code tracking loops: DLL, non-coherent vs. coherent tracking, correlator spacing and carrier aiding
• Tracking of open satnav signals: GPS, GLONASS, Galileo and BeiDou
• Internal decision making and control procedures based on signal environment and application
• Measurement computation (pseudorange, accumulated Doppler range/carrierphase)
• (New!) Direct instantiation for multi-frequency tracking (e.g. Galileo E1 to E5a/b)
• (New!) Inter-frequency aiding and duty cycling techniques for low power applications

Pre-requisites and equipment: Basic understanding of digital signal processing, object-oriented programming concepts and the Python programming language are helpful but not required to attend this course. Numerous fully-functional demo projects will be provided. If intending to run the demos during the course, attendees must supply their own laptop computers with adequate battery power. The instructors will provide relevant information and software to registered attendees in advance of the course.

Dr. Sanjeev Gunawardena is a research associate professor with the Autonomy & Navigation Technology (ANT) Center at the Air Force Institute of Technology (AFIT). He has over 20 years of experience in RF, digital and FPGA-based system design. His expertise includes satnav receiver design, advanced satnav signal processing and implementation. Dr. Gunawardena received a BS in engineering physics and a BSEE, MSEE and PhD EE from Ohio University.

Mark Carroll is an electronics engineer with the Air Force Research Laboratory Sensors Directorate. He received his BS in Computer Engineering and MS in Computational Science and Engineering from Miami University, Oxford Ohio. His research interests include satnav, satnav SDRs, and machine learning.

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Factor Graphs

Date/Time:
In-Person and Virtual Attendees: Tuesday, September 20, 1:30 p.m. - 5:00 p.m. MDT
Recording: Course registrants who do not attend the live course (either in-person or virtually) may view a recording of the course one time within 30 days.
Room: Mineral Hall FG (Third Floor)

Registration fee:
$400 if registered and paid by August 19
$450 if payment is received after August 19

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 received a PhD from West Virginia University with a primary focus on robust estimation for navigation applications (e.g., GNSS process in signal degrading environments). Ryan currently works at the Johns Hopkins University Applied Physics Laboratory where his focus is on estimation for robotic and space missions.

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.

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GNSS Integrity

Date/Time:
In-Person and Virtual Attendees: Tuesday, September 20, 1:30 p.m. - 5:00 p.m. MDT
Recording: Course registrants who do not attend the live course (either in-person or virtually) may view a recording of the course one time within 30 days.
Room: Mineral Hall DE (Third Floor)

Registration fee:
$400 if registered and paid by August 19
$450 if payment is received after August 19

Course Level: Beginner to 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.

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GNSS in the National Airspace

Date/Time:
In-Person and Virtual Attendees: Tuesday, September 20, 1:30 p.m. - 5:00 p.m. MDT
Recording: Course registrants who do not attend the live course (either in-person or virtually) may view a recording of the course one time within 30 days.
Room: Capitol Ballroom 1 (Fourth Floor)

Registration fee:
$400 if registered and paid by August 19
$450 if payment is received after August 19

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.

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