Files needed Station information that gives position of ARP relative to ground mark. Strictly this should be in RINEX file header but is often incorrect. Getting this information correct is often the biggest problem in campaign GPS processing. Information is ecorded on paper log sheets that need to be transcribed correctly. Often referred to as meta-data for RINEX file priori coordinates and velocities for sites(can extract position from RINEX header but these are often not very Apriori orbit information for satellites. If working near real-time than maybe use"yesterdays"orbit extrapolated forward Atmospheric and water loadi available although some grou a local press when comp results) Specific programs The files before are generic that all programs need. Specific programs use other files to control them We will examine gamit which the mit developed GPS program. There are two basic modules: GaMit and gloBK04/30/03 12.540 Lec 20 7 Files needed ground mark. Strictly this should be in RINEX file header but is often incorrect. Getting this information correct is often the biggest problem in campaign GPS processing. Information is recorded on paper log sheets that need to be transcribed correctly. Often referred to as meta-data for RINEX file. position from RINEX header but these are often not very good) If working near real-time Not normally used or available although some groups use a local pressure admittance model (need to be careful when comparing results). 04/30/03 12.540 Lec 20 8 Specific programs need. – Station information that gives position of ARP relative to – Apriori coordinates and velocities for sites (can extract – Apriori orbit information for satellites. than maybe use “yesterdays” orbit extrapolated forward. – Atmospheric and water loading. • The files before are generic that all programs Specific programs use other files to control them. • We will examine GAMIT which the MIT developed GPS program. There are two basic modules: GAMIT and GLOBK 4