Analysis and simulation of system phase errors in planar near-field measurements on ultra-low sidelobe antennas

System phase errors are one of the main error sources to influence the precision of planar near-field antenna measurements, especially for planar near-field measurements on ultra-low sidelobe antennas. In this paper, the effect of system phase errors on the results of planar near-field measurements on ultra-low sidelobe antennas is studied by means of theoretical analysis and computer simulation. The analytical expression of the error spectrum in the sidelobe region due to system phase errors is derived and some basic laws and useful results are obtained.