MIT ICAT GPS XYZT The Global Positioning System Measurements of code-Phase arrival times from at least four satellites are used to estimate four quantities: position in three dimensions (X, Y, 4)and GPS time( T) Courtesy of Peter Dana. Used with permission. P: H: Dana: 540.98 Fromhttp://www.colorado.Edulgeographylgcraft/noteslgpslgpsf.htmlMIT ICAT GPS From http://www.Colorado.Edu/geography/gcraft/notes/gps/gps_f.html (Courtesy of Peter Dana. Used with permission.)