Status and future plans for the VieVS scheduling package

Transcription

1 2th EVGA Meeting March 29-31, 211 Bonn, GERMANY Session 1 Status and future plans for the VieVS scheduling package Jing Sun, Andrea Pany, Tobias Nilsson, Johannes Boehm, Harald Schuh

2 What s the purpose of a scheduling program? skd file Scheduling Program skd file Station DRUDG prc file, snp file FS log file Correlator Current scheduling programs : sked (Goddard) sched (NRAO)...

3 Why is a new scheduling program needed? VLBI21 Goals 1 mm measurement accuracy on global baselines; continuous measurements for time series of station positions and EOP; turnaround time to initial geodetic results of less than 24 hrs. VLBI21 Specifications small fast-moving antennas; broadband frequency (2 14 GHz); two or more antennas at a site;...

4 Structure of VIE_SCHED sources stations VIE_SCHED observing modes 1. Calculate the possible configurations 2. For each possible configuration For each scan in the configuration Calculate the start time Calculate duration for each station Check it and store it by rank End End 3. Select the configuration with the highest rank considering the criteria skd file ngs file 4. Enter the selected configuration into the schedule

5 Calculate the possible --- The source is up at the current time. configurations Structure of VIE_SCHED --- The source is strong enough on each baseline of a scan. --- The same source won t be repeated in a short time. --- If the source is too close to the sun, it won t be considered.

6 Structure of VIE_SCHED Criteria of optimization Criteria of evaluation number of observations sky coverage time between scans covariance analysis station position repeatibilities repeatibilities baseline length repeatibilities repeatibilities RMS of EOP other parameters

7 VLBI21 simulation Schedule Interim network : 18 stations 9 station distribution Latitude [deg] Longitude [deg] --- legacy antennas

8 VLBI21 simulation Schedule Number of observations From SKED (red) From VIE_SCHED (blue) Number of sources number of scans number of observations number of observations slow medium fast

9 VLBI21 simulation Schedule Idling percentage From SKED From VIE_SCHED percentage value obs slew idle percentage value obs slew idle slow medium fast slow medium fast

10 VLBI21 simulation Schedule Mean sky coverage 13 sky coverage distribution 12 sky coverage value from SKED from VIE SCHED slow medium fast

11 VLBI21 simulation Simulation the refractive index structure constant Cn : the effective height of wet troposphere H : 2 [m] the wind velocity vector v (8. m/s) towards east the Allan standard deviation (ASD) of 5 min the white noise : 16 ps per baseline Results 7 6 from VIE SCHED from SKED 5 Median 3D repeatability from SKED = 3.3 mm 3D 4 3 Median 3D repeatability from VIE_SCHED = 3.45 mm slow medium fast

12 The study of NYALES2 station Schedule(IVS-R1464) Network 9 station distribution Latitude [deg] Longitude [deg] Sta index Sta name BADARY HARTRAO KOKEE NYALES2 MEDICINA ONSALA6 TIGOCONC TSUKUB32 WESTFORD WETTZELL Cn

13 The study of NYALES2 station Schedule(IVS-R1464) Number of observations Network1 (9 sta) (original network) Network2 (8 sta) (without NYALES2) Network3 (9 sta) (8 stations + MEDICINA) Number of sources number of scans number of observations number of observations number of observations number of observations

14 The study of NYALES2 station Results(IVS-R1464) ERP & St. dev [uas, uas, us] station position repeatability [mm] Network1 (9 sta) (original network) [ ] [ ] Network2 (8 sta) (without NYALES2) [ ] [ ] Network3 (9 sta) (8 stations + MEDICINA) [ ] [ ] baseline length repeatability [mm] Mean 3D repeatability = 8.5 Mean 3D repeatability = 8.84 Mean 3D repeatability = Baseline length [Mm] Baseline length [Mm] Baseline length [Mm]

15 The study of NYALES2 station Schedule(IVS-R4464) Network 9 station distribution Latitude [deg] Longitude [deg] Sta index Sta name BADARY KOKEE MEDICINA NYALES2 MATERA SVETLOE TIGOCONC WETTZELL ZELENCHK Cn

16 The study of NYALES2 station Schedule(IVS-R4464) Number of observations Network1 (8 sta) (original network) Network2 (7 sta) (without NYALES2) Network3 (8 sta) (7 stations + MATERA) Number of sources number of scans number of observations number of observations number of observations number of observations

17 The study of NYALES2 station Results(IVS-R4464) ERP & St. dev [uas, uas, us] station position repeatability [mm] Network1 (8 sta) (original network) [ ] [ ] 8 6 Network2 (7 sta) (without NYALES2) [ ] [ ] Network3 (8 sta) (7 stations + MATERA) [ ] [ ] Mean 3D repeatability = 8.63 Mean 3D repeatability = 1.2 Mean 3D repeatability = 1.9 baseline length repeatability [mm] Baseline length [Mm] Baseline length [Mm] Baseline length [Mm]

18 Ongoing and planned developments of VIE_SCHED o Covariance analysis optimization criteria o More analyses and comparisons with sked, sched and other scheduling packages o Spacecraft tracking o...

19 Summary VIE_SCHED is a new scheduling program written in Matlab, which is a part of VieVS software. Results of similar quality as from sked package. VIE_SCHED is also available free of charge to registered users.

20 DGFI Munich, R. Heinkelmann THE NICT Japan, T. Hobiger? END Thank You for listening! Jing Sun would like to thank the FWF for funding project SCHED21 (P2149). Andrea Pany is a recipient of a DOC-fFORTE fellowship of the Austrian