The full guide to using Calc/Solve is here. The following information describes the process used at Hobart and is aimed at
routine processing of post-correlation data.
Level 2 databases have an updated clock model applied (using calc11), replacing the model used by the correlator. To generate new databases, edit the
up11.inputs file with the new database names (note the leading
and then run
up11 up11.inputs AU. After completion, you should have
Level 3 databases have cable cal and MET data added to provide an apriori atmosphere model. This is usually only applied to the X-band data. First, download the station log files with
wget http://lupus.gsfc.nasa.gov/ivs/ivsdata/aux/2014/aust19/aust19hb.log, etc. Then run
pwxcb aust19hb.log. You will be prompted to confirm some details of the experiment, and optionally edit the recorded MET data. When running pwxcb for the first log of an experiment, you will be prompted to give name of the database that this experiment is linked to - use the same syntax as in the up11 file (e.g
$14FEB05XT). Repeat pwxcb for all stations in the experiment and then apply the calibrations by running
dbcal /data/vlbi/wxcb/aust19.dbcal. After completion, you should now have a
14FEB05XT_V003 file in
First start Calc/Solve with the command
enter AU. Once inside the Calc/Solve system, be extremely careful with your typing as almost any keypress can and will be quietly interpreted to change various settings. Also, default settings may not always be displayed, or displayed correctly on start-up. A last warning - Calc/Solve always starts up with the same data & settings loaded as when it was last run. To restart an analysis you should re-load the data, overwriting any previous databases in memory.
Gto get some data through the SDBH program. Tap
*to toggle the mode between between the append and replace modes. Use replace if starting afresh. Type
Kto enter the X-band database and version number (
$14FEB05XT 03). Press enter to read the history file and a list of aprioris until you get back to the SDBH window. NB - you msy see some Warnings about Hart15 not being in the Flyby file - these are benign. Toggle the mode to append with
*, and then use
Kto load in the S-band database. Again, review the information by pressing enter until you reach the SDBH window again & then return to the main window by pressing
#. Then press
Nto change to the S-band database and repeat. Return to the main menu with
3to use Group Delays only, and make sure that no EOPs are being estimated - you can move around the text menus with the arrow keys and toggle some variables by pressing the space bar. The screen should look like this:
Polar motion and UT1: Polynomial Parameterization SETFL Ver. 2007.07.30 14/02/05 19:00 XWOB Coefficients 0 0 0 0 14/02/05 19:00 YWOB Coefficients 0 0 0 0 14/02/05 19:00 UT1 Coefficients 0 0 0 0 Select:(/)G.Rate & Segments (%)Only Segments (|)Sine Style (@)Reset Poly Epoch Gamma, Precession rate 0 0 Nutation(.): Dpsi, Deps 0 0 Print residu(A)ls: OFF Print corr. (M)atrix: OFF Print (N)ormal Matrix: OFF (Z)ero Normal Matrix: OFF (^)Elev. cutoff: None Pick parameters: (!)Sites OFF (#)UT1/PM Wea(K) Station Constraints: OFF (R)Use rate: Yes Use normally (W)eighted delays Select: Baseline-(C)lock offsets (:)Delay Group (;)Rates Off Select: (B)aselines, (X)Data bases Page: (E)Site (S)ource (O)ptions (")Constraints (Q)Run least squares (T)erminate SOLVE (<)A priori clock (+)Change data type Group delay only (')Change suppression method SUPMET__PRE98 (-) Singularity check Last page Parms used / Max parms available: 20/ 2000
E to set up the site parameters. For the initial solution, set the Clock Polynomials line to
1 1 1 0 0 * * * for every station bar one (the reference station - choose the same one as was used for a reference in fourfit). You can change between the stations with the
P button. Make sure that all other parameter estimations are set to zero for all stations & beware of errant keypresses. Once ready, you can geenerate a solution by pressing
The solution will be writtento the screen. Check that the Weighted RMS in delay is < 1 microsecond (if greater, suggests strong outliers or systematic problems). Also, check the second page where the clock solutions are listed:
1. HART15M CL 0 14/02/05 06:59 -7063.162 ns 1.95 ns 2. HART15M CL 1 14/02/05 06:59 76.263 D-14 9.44 D-14 3. HART15M CL 2 14/02/05 06:59 14.85-14/d 9.13-14/d 4. HART15M NG 14/02/05 06:59 -44.17 mm 48.37 mm 5. HART15M EG 14/02/05 06:59 -140.18 mm 41.28 mm 6. HART15M NG 14/02/06 06:59 138.50 mm 46.24 mm 7. HART15M EG 14/02/06 06:59 -151.57 mm 36.44 mm
CL 0 is greater than 100000 ns (100 microsec) or
CL 1 > 100000 D-14 in rate then you will need to apply an apriori clock model or, better yet, recorrelate the data. See the solve guide for instruction on applying a priori model. If the solution is ok, return to the main menu with
A. Change the minumum quality code to 5 by pressing
5. Start the process by pressing
Aand check the printed results. You will sometimes encounter warnings like this:
GAMB S-band: r.m.s. of whole solution is OK GAMB $b$ group ambiguities are resolved, but solution looks bad Are you sure, that you really need to save these results in scratch file ?
These are usually caused a few bad sources/observations - press
S to save the results and return to the main window.
C. Set the reference clock by entering the station number, and then press
M. Generate a new solution by pressing
Q. The weighted RMS of the solution should be in the range of 550-1500 ps and the magnitude of the baseline clocks should be < 1 ns. If now, refer to the guide on how to deal with permanmet ambiguities (this hasn't been necessary yet). Retun to the main page with
Pto start the plotting program. Press
Xin the pgplot window to return to the main window.
Eto get to the
Nto select the correct station and then press
*to reveal and change the method until you get
Insert(other options are
Automaticwhich is the default). Then press
C, and enter the time of the clock break. Press enter on an empty line when all the clock breaks have been inserted. You should now have additional entries for clock polynomials - use the arrow keys to highlight the first three zeroes and use the pace bar to toggle them to ones. The section below shows the set up for Katherine in aust19 which had two clock breaks at 035-133000 and 035-191200.
Clock polynomials 14/02/05 06:59 1 1 1 0 0 * * * 14/02/05 13:30 1 1 1 0 0 * * * 14/02/05 19:12 1 1 1 0 0 * * *
7to set the solution type to
3to change the suppression method to SUPMET__COMB1.
4(press enter) to set up the singularity check with the recommended parameters. Press
Sto save & return.
Eand toggle mode to Automatic with
Cand set the time interval to 300 minutes (
300), polynomial order to 2 (
2), and use Batch mode (
B). Set the reference station as before.
Ato estimate the atmosphere. Use an interval of 300 minutes and batch mode
Oand then go to the Weighting menu with
Cto add a noise floor to the weights, then save areturn to the main menu with
Q. If the weighted RMS is < 150 ps, things are likely ok. You should be able to produxe a version 4 database and NGS file at this stage if you want to work on the data in VieVS/OCCAM/etc. This avoids calc/solve flagging
outliersautomatically. To proceed on to obtain a final solution, read on.
\. Set recommended parameters with the following commands:
C(press enter). When ready, the screen should look like this:
Automatic outliers elimination utility ELIM Ver. 2007.08.01 ����������� $14FEB05XT <3> 'SUPMET__COMB1' Information about residuals is not available yet (X) Maximum uncertainty: 1000. psec (A) Acceleration factor: 1 (U) Upper threshold for outlier detection: 400. psec (E) EQM speed-up: No (C) Cutoff limit for outlier detection: not specified (Y) Type: baseline (Q) Quality code limit: 5 (D) Update residuals (-) Singularity check (') Change suppression method (V) Verbosity level: 1 (N) Confirm each action: no (S) Return to Optin and save results (O) Return to Optin without saving (P) Proceed for outliers elimination (T) Toggle elimination/restoration (W) Weights update (H) On-line help
Pto proceed with detection & elimination & press
Sto save the results & generate a new solution. If the wrms is between 15 and 100 psec with the
used observationsprecetage > 80%, then it's regarded as good. Significantly worse wrms/low acceptance suggests mishanded clock breaks, un- or mis-applied calibration, or maybe a bad station.
Lto enter the estimation menu. Press
.to esimate nutation and press
#to estimate EOPs. Use the arrow keys to change the UT1 coefficients line to
UT1 Coefficients 0 1 0 0
Eto enter the site menu. Toggle mode to Automatic with
*and then set up both blocks (
C) and atmosphere (
A) using batch a 1 hour interval and batch mode. Set up gradient estimation with
Gand choose a 50 hour interval.
Q. Check the text listing makes sense and inspect the residuals (
P) and estimated parameters (
You can do this at any stage after running GAMB which handles the ambiguity resolution & ionospheric correction process. It's a two-tage process of creating an updated database & the running a DOS script to convert it to NGS format.
U. Make sure that only the X-band database is selected and then press
7to set the options as shown below. Press
Database update NEWDB Ver. 2007.06.05 ------------------------------------------------------------------------------- Database to be updated: $14FEB05XT Reweighting: (G)roup (P)hase (B)oth (#)None (1) Clk & atm parms, constraints, data configuration-->Yes No (2) Group delay editing and ambiguities--------------->Yes No (3) Group ionosphere calibration:--------------------->Yes No (4) Met., cable, phase cal status:-------------------->Yes No (5) Ocean, relativity, pole tide status:-------------->Yes No (6) Phase delay editing and ambiguities--------------->Yes No (7) Phase ionosphere calibration:--------------------->Yes No (N)ext Menu (O)PTION (R)efresh Screen (D)efault standard (T)erminate SOLVE Re(S)elect Databases
” or “key not found”, etc, this is usually due to the database having already been updated. If this fails, you'll need to exit calc/solve , delete the offending file from /data/vlbi/mark3_dbh/ and from the catalogue. You can do this with the
catlg program. Use the
de command (with
-1 as the “password”), select
e for entry and then confirm the deletion of the most recent version. Once deleted, you should be able to run the update as per normal.
wine cmd.exe. Then run
MK3NGS2.EXE /data/vlbi/mark3_dbh/14FEB05XT_V004. The output file will be written into the current directory as 140205XT.NGS and is now ready. Note that VieVS expects a filename like 14FEB05XT_N004 though.