Bernese GPS Software Version 5.0 - Bernese GNSS Software

22. Data Structure
Used by: ORBGEN (”Menu>Orbits/EOP>Create standard orbits”) in the UPDATE mode and
STDPRE (”Menu>Orbits/EOP>Convert standard to precise orbits”) to derive approximated
rms values of the orbit quality for each satellite.
Example: Figure 22.22: In the example file each arc is characterized by 18 orbital
elements (6 Keplerian elements, 9 radiation pressure coefficient parameters,
and 3 pseudo-stochastic parameters at the middle of the arc).
${X}/DOC/EXAMPLE.ELE is also available.
Information concerning the orbit parameterization is given in Chapter 15.
The first column contains the a priori orbital parameters, column 2 and 3 the improved values
and their rms. An asterisk “*” indicates that a parameter was not estimated, ORBSYS 2
in the last column defines the orbital system (ORBSYS 1: B1950.0, ORBSYS 2: J2000.0), and
the string T950101B characterizes, if present, the a priori model for radiation pressure and
the orbit model used (orbit model flag “B”). Pseudo-stochastic orbit parameters are listed
at the end of the file.
22.7.7 Pole File in IGS/IERS Format
Type: ASCII
Directory: Campaign-specific directory ORB.
Extension: IEP
Content: Pole coordinates, UT1-UTC, and nutation offsets together with statistical
information.
Created by: Parameter estimation program GPSEST (”Menu>Processing>Parameter estimation”)
or ADDNEQ2 (”Menu>Processing>Normal equation stacking”) or by other IGS analysis
centers.
Used by: Extraction programs POLUPD (”Menu>Orbits/EOP>Handle EOP files>Convert IERS to
Bernese format”), POLXTR (”Menu>Orbits/EOP>Handle EOP files>Concatenate IERS pole
files”), submission format of Earth rotation parameters for IERS and IGS.
Example: Figure 22.23 shows Earth rotation estimates in theIEP format stemming from
a 3-days arc. The right-most columns listing the correlations and nutation
estimates are not reproduced. ${X}/DOC/EXAMPLE.IEP is also available.
This file is only used to send pole, UT1-UTC, and nutation information from global Earth
rotation parameter estimations to the IERS Bureau. ERP information is provided in this
format by the IGS. Note that starting on GPS week 0966 a new version of the format (version
2) was implemented for all official IGS products in order to get an increased resolution
for the polar motion coordinates, their rates, UT/LOD, and their respective sigmas (see
IGSMAIL #1943). The reading routines in the Bernese GPS Software read the old and the
new format (together with about 13 different pole fileformats).
Files from external sources have the extension ERP. In order to avoid confusion with Bernese
ERP files rename external files to names with extension IEP.
Page 508 AIUB