GPS Geodesy

mongolia gps

In the late 90's, space-based geodetictechniques such as the Global Positioning System (GPS)reached a level where millimeter-level positioning becameachievable globally. In geophysics, GPS measurements havebeen widely used over the past decade to monitor crustaldisplacements, with precision levels on the order ofa few mm/yr now routinely achieved.

In addition to science applications, GPS has becomean essential part of the infrastructure of today's societyand represents a significant commercial and job market.Application range from surveying, navigation, transportation,GIS, to geophysics. GPS is now one of several positioningsystems grouped under the "Global Navigation Satellite System"(GNSS).

This course will provide a fundamental understandingof the theory and practice of GNSS, with an emphasis onhigh-precision applications using GPS. Other space geodetictechniques (VLBI, SLR, DORIS) will be mentioned andreference frame issues will be addressed.

The labs will provide hands-on experience in field anddata processing techniques, including programming a simpleGPS data processing software and learning to use a high-endresearch software (GAMIT). Prerequisites are working knowledgeof Matlab (or fluency in a programming language such as Cor Fortran), and a course in linear algebra.


Lectures



Labs (findsolutions here)

  1. Lab 1:Getting used to Unix/Linux and Matlab[pdf]
    See also:Matlab introduction
    See also:very short Matlab intro
  2. Lab 2Coordinate systems[pdf]
  3. Lab 3:Manipulating sp3 orbits[pdf]
    Find igs11376.sp3.Zhere
    Or download it fromSOPAC
  4. Lab 4:From GPS ephemerides to ECEF positions[pdf]
    Find epgga2.010.Zhere
    Find igs11484.sp3.Zhere
  5. Lab 5:GPS data quality control[pdf]
    Find sjdv0100.02ohere
    Find PU07200910160000.09ohere
  6. Lab 6:Surveying with GPS: field measurements, rinexing and quality control[pdf]
    A typicallog sheet for campaign measurements
    A typicallog sheet for continuous measurements
    Find TEQC web sitehere
  7. Lab 7:Pseudorange position solution[pdf]
  8. Lab 8:Processing a 24-hour RINEX observation file[pdf]
  9. Lab 9:High-precision processing of GPS data: GAMIT/GLOBK (1/3)
  10. Lab 10:High-precision processing of GPS data: GAMIT/GLOBK (2/3)
  11. Lab 11:High-precision processing of GPS data: GAMIT/GLOBK (3/3)
  12. Lab 12:Term project oral presentations



Term project

Must involve handling and processing of GPS data for a high-precision (cm-level or better) application. You may choose a topic related to your graduate research or something new you are interested in learning more about.


Grading system

Grading will be based on:

  1. Lab and home work, 30% of grade:Assignments will be given at the beginning of each lab. Any part of the assignment not finished during the lab will be done as homework and must be returned to the TA by the beginning of the next lab session.
  2. Term project, 30% of grade:
    • Written report in the form of a 4-page paper including figures (e.g., format ofGeophysical Research Letters). Project reports must include (1) an Introduction section describing the problem to be addressed and its broader significance, (2) a Data section describing the selected GPS data set, (3) an Analysis section describing the analyses of the data set, (4) a Discussion section, describing the results of the data analyses and their implications for the studied problem, and (5) a Conclusion section, summarizing project results.
    • 10-minute talk in class at the end of the term (e.g., in the style of an AGU oral presentation).
  3. Midterm exam, 20% of grade
  4. Final exam, 20% of grade



Suggested reading

Some fundamental papers on the basics of GPS:


Books:

  • GPS, Theory and Practice, B. Hofmann-Wellenhof et al., Springer-Verlag.
  • GPS Satellite Surveying, A. Leick, John Wiley and Sons.
  • Linear Algebra, Geodesy, and GPS, G. Strang and K. Borre, Wellesley-Cambridge Press.
  • Understanding GPS, Principles and applications,Kaplan, Artech House Publishers.
  • GPS for Geodesy, Kleusberg and Teunissen (Eds), Springer, 1996.
  • A guide to GPS positioning, Wells and coll., Canadian GPS Associates, Univ.New Brunswick, 1996.


A few WWW sites: