HR: 1340h
AN: G43C-1472    [Abstracts]
TI: Accuracy and Stability of the Terrestrial Reference Frame Realized by the Future Network of VLBI2010 Stations
AU: * MacMillan, D S
EM: dsm@leo.gsfc.nasa.gov
AF: NVI, Inc./NASA GSFC, Code 698, Greenbelt, MD 20771, United States
AU: Ma, C
EM: cma@leo.gsfc.nasa.gov
AF: NASA GSFC, Code 698, Greenbelt, MD 20771, United States
AB: To design the future global geodetic network of VLBI2010 stations, the IVS is performing simulations to determine optimal network antenna locations, VLBI station specifications, and antenna observing strategies. The desired goal is a system that will determine the terrestrial reference frame (TRF) with an accuracy of 1 mm and stability of 0.1 mm/yr. We first describe the simulation procedure and its validation using observed data. Validation involves verifying that measures of geodetic precision (e.g., repeatability) derived using simulated geodetic delay data are at the level obtained from analysis of observed data. The current global coverage with VLBI antennas suffers from poor Southern Hemisphere coverage. By analyzing results from simulated networks with different global distributions, one can investigate the systematic effects due to non-uniform geographical distribution of VLBI sites. For instance, one can determine how the precision of TRF scale and Earth orientation of a VLBI network depends on the number and distribution of VLBI antennas. Preliminary analysis shows that Earth orientation parameter and TRF scale precision improves with network size by a factor of about 2 as the network size increases from 8 sites, which is the typical size of current operational VLBI networks, to a network of 32 sites. We use simulation analysis to determine the tradeoffs between number of antennas, VLBI station specifications (e.g., antenna slewing rate and sensitivity), and delay observable precision in realizing the desired TRF accuracy and stability goals.
DE: 1229 Reference systems
DE: 1239 Earth rotation variations
DE: 1294 Instruments and techniques
DE: 6964 Radio wave propagation
SC: Geodesy [G]
MN: 2007 Fall Meeting