GPS Observables Today's class we start discussing the nature of GPS observables and the methods used to make range and phase measurements Start with idea of remotely measuring distances
GPS Groups/Gs There are many international and national groups involved in the deployment of GPS The international organization is the International GPs Service(IGs)
Treat the basic description and dynamics of satellite orbits Major perturbations on GPS satellite orbits · Sources of orbit information: -SP3 format from the International GPS service Broadcast ephemeris message
Primary research programs Geophysical research GPS analysis packages GAMIT (GPS at MIT): Uses double differences GYPSY: Jet Propulsion Laboratory (JPL) processing packages: Uses one-way observables and explicitly estimates clocks Bernese: Developed at Astronomical Institute
Today's Lecture Examine specifics of GPS signals Multiple modulations on same carrier signal Structure of signals GPS receiver operation and satellite acquistion
