"Methods of Theoretically Calculating the Vector Structure of the Electromagnetic Field in the Near Zone of an Aperture Radiator"

"This paper analyzes and compares various methods of analytically calculating the spatial dependence of vectors of the electromagnetic field generated by an aperture antenna in the near zone. A literature review of methods of theoretical computation of aperture radiation with a given boundary field distribution in the frequency domain is performed, on the basis of which they are divided into two large groups. Methods of the first type are based on a separate consideration of each field component using the scalar wave equation, while the second, more extensive, class of methods relies substantially on the vector effects; in addition, all methods are compared in terms of the amount of information required for their use. An example with a specific electrodynamic model is considered, which makes it possible to carry out a quantitative accuracy characteristics comparison for the computational relations listed in the paper. The main results from the field of alternative approaches based on the calculation of impulse responses in the time domain are also given."