A system for generating and utilizing a look-up mechanism consisting of one or more phase difference error maps, tables and/or mathematical models calculates the respective maps, tables and/or models by placing a short baseline or ultra-short baseline antenna array in a known location and known orientation, determining angles of incidence of incoming GNSS satellite signals with respect the antenna array and calculating expected carrier phase differences between respective pairs of antennas, calculating measured carrier phase differences between the respective pairs of antennas, and determining carrier phase difference errors using the expected and measured carrier phase differences. The carrier phase difference errors are then recorded in the look-up mechanism, with the maps and, as appropriate, look-up tables for the respective pairs of antennas being indexed by angles of incidence. Thereafter, the system utilizes the look-up mechanism when determining the unknown orientation of the antenna structure. For respective pairs of antennas, the system enters the look-up mechanism based on angles of incidence determined from a calculated orientation, and uses the retrieved values in the calculation of a corrected orientation, to compensate for phase distortion.