A priori guaranteed accuracy evaluation in determining spacecraft orbit by least squares method

In an a priori estimation of the expected accuracy of orbit determination, it is assumed that all the initial data (measurements and a priori information concerning the parameters of the mathematical model) can be divided into groups between which and within which are specified different constraints on the correlation coefficients between errors. Formulas are derived for calculating the guaranteed value of the error of the estimate variance of any estimated parameter when performing single or repeated measurements.