Assessing the Accuracy of Geodetic Measurements for the VLBI2010 Observing Network

We have previously investigated the precision of geodetic estimates made by the next generation VLBI2010 observing network by using simulations to show that the planned network yields high precision results. In this presentation we seek to determine the expected accuracy of the results. To do this, we have simulated the performance of the network using known input contributions, such as troposphere and clock delays, measurement noise, and troposphere mapping functions. These contributions propagate to the estimates of desired geodetic parameters, including station coordinates, baseline lengths, and Earth orientation parameters. By comparing the estimated values of parameters with the known input values, we can evaluate biases that might result from the modeling. We also consider how network geometry can lead to biases. For comparison, we also investigate the accuracy and precision of current VLBI observing networks using the same simulation model and parameters. We also study the impact of alternative estimation strategies on the accuracy of VLBI estimates.