Analysis of Large-Scale Phased Antenna Array With Generalized Transition Matrix

This paper presents a numerical method to evaluate the electromagnetic radiating characteristics of a large-scale phased antenna array by using generalized transition matrix modules. Choosing an appropriate reference surface to contain an antenna element, an associated generalized transition matrix (GTM) is defined to establish the relationships between the rotated tangential components of incident field and scattered field on the reference surface. Meanwhile, a mapping vector is constructed to map the excitation sources onto the reference surface as the rotated tangential radiation field components. A GTM module for an antenna unit with feeding source consists of a GTM, a mapping vector, and a specified reference surface. The radiation pattern and mutual coupling effects among units can be analyzed by using the GTM modules of all units, in conjunction with the generalized surface integral equations (GSIEs). The interaction of the excitation port information is included in the field transmission process between the GTM modules as well. For a phased antenna array with fixed element structure and array size, the GTM modules and the coupling matrices among units do not change with the amplitude or phase of the feeding sources. The proposed method is particularly efficient to analyze the property of beam scanning and sidelobe level adjustment of a large-scale phased antenna array. Numerical results are provided to verify the high efficiency and precision of the method.