Course 551: Using Advanced GPS/GNSS Signals and Systems (3.0 CEUs) On-Site Course
This 5-day course will enable attendees to achieve proficiency, not merely familiarity, with the essential aspects of using GPS / GNSS signals. (Course 551 includes discussions on Kalman fItering not covered in Course 541, a 4-day course). will not only thoroughly address current and future GPS signals, but also drill deeply into available details of signals from other satellite-based positioning and timing systems. As attendees understand similarities and distinctions between different systems and signals, they will become equipped to take advantage of signals from multiple systems.
Receiver processing techniques are described along with ways to characterize the performance of receiver processing. These processing techniques are customized to specific characteristics of signals from GPS and other satnav systems. Specialized topics, including dealing with interference and with multipath, differential satnav, and assisted satnav, are also addressed.
Attendees will be given review questions each evening that will be reviewed in class each morning. Working the review problems in class helps attendees understand and apply key concepts.
To develop proficiency with advanced receiver processing of modernized and new signals from GPS, GLONASS, Galileo, BeiDou, and QZSS, supplemented by systems engineering skills, integrated with techniques for assessing performance and performing design trades concerning receiver processing.
Attendees should already have a solid background in GPS and be ready to develop advanced skills. Previous exposure to basic signal processing techniques and terminology and to matrix algebra as well as familiarity with engineering mathematics is needed.
This extensive, fast-moving course is targeted to engineers, scientists and professionals who already have a solid background in GPS and are ready to develop advanced skills in using GPS and other satellite-based navigation and timing systems. Attendees should have previous exposure to basic signal processing techniques and terminology. Familiarity with engineering mathematics is needed.
Objectives: Review basics of satellite-based positioning and timing, establish common terminology and notation, explore satellite orbits and constellations, understand satnav signal fundamentals.
Introduction and Overview of the Course
SatNav Orbits and Constellations
● Kepler's laws
● Constellation design considerations
● Useful geometry calculations
● Signal overview
● Spreading modulations
Objectives: Establish rigorour mathematical models of satnav signals, become proficient with systems engineering tools
● Signal components
● Space to Earths
● Building and vegetation effects
Errors in Satnavs
● Error sources and error budgets
● Dilution of precision
● Error measures and relationships among error measures
Objectives: Review Day 1 material, begin to explore details of GPS and its signals, both original and modernized.
Day 1 Review Questions and Answers
GPS and SBAS Overview
● C/A signal
● L2C signal
● M signal
● L5 signal
Objectives: Complete exploring details of GPS signals and SBAS signals, begin receiver engineering with an overview, followed by details of receiver front end design.
● L1C signals
● Summary of GPS signal characteristics
● L1 SBAS
● L5 SBAS
Overview of Receiver Processing
Receiver Front End Design
● Noise figure
● Receive Antennas and filters
● Active components
Objectives: Review Day 2 material, address details of analog-to-digital conversion, introduce initial synchronization.
Day 2 Review Questions and Answers
Analog to Digital Conversion
● Linear ADC
● ADC for the digitizing correlator
● Replica aliasing
Initial Synchronization Overview
● Receiver states
● Time-frequency search and the cross ambiguity function
● Widening BOC correlation functions
Objectives: Describe approaches for massively parallel initial synch and evaluating initial synch performance, describe procedures for tracking loop design and implementation, followed by carrier tracking
Initial Synchronization Details
● Architectures for massively parallel computation
● Code Doppler
● Initial synchronization performance assessment
● Other aspects of acquisition
● Implementation and trade-offs
● Carrier tracking
● Frequency-locked loop design and performance
●Costas loop design and performance
●Phase-locked loop design and performance
Objectives: Review Day 3 material, address details of code tracking and data message demodulation.
Day 3 Review Question and Answers
● RMS bandwidth and its influence on code tracking performance
● Signal processing and discriminators for code tracking
● Implementation and trade-offs
● Performance prediction
● False lock points
Data Message Demodulation
Objectives: Describe algorithms and considerations for calculating position, velocity, and time; provide integrated view of dealing with interference; introduce Galileo system and signals
Position, Velocity, Time Calculation
● Generating and refining observables
● Correcting ionospheric, tropospheric, and clock errors
● Position calculation
● Underdetermined solutions
Dealing with Interference
● Interference effects
● Interference mitigation
Galileo system and Signals
● E1 OS
● E1 PRS
● E6 CS
● E6 PRS
Objectives: Review Day 4 material, complete description of Galileo signals, describe Galileo receiver processing.
Day 4 Review Questions and Answers
Galileo System and Signals
● E5, E5a, E5b
● E1 OS receiver processing
● E5 receiver processing
Objectives: Summarize other satnav systems and signals (GLONASS, BDS, QZSS), provide overviews of differential satnav, assisted satnav, and multipath considerations, wrap-up course.
Other Satnav Systems and Signals
Block Processing and Assisted Satnav
Dealing with Multipath