Topraklanmış düzlemsel ve silindirsel dielektrik yüzeyler üzerindeki faz dizilimli ve sonlu baskı devre antenlerin incelenmesi

Printed structures, in the form of a single printed antenna (printed dipole, patch,etc.) or an array of printed antennas on planar and cylindrical grounded dielectricslabs, are investigated. Full-wave solutions based on the hybrid method of mo-ments (MoM)/Green?s function technique in two different domains, the spectraland the spatial domains are used to analyze these types of geometries. Several nu-merical problems, encountered in the evaluation of both the spectral and spatialdomain integrals are addressed and solutions for these problems are presented.Among them the two important ones are: (1) The infinite double integrals whichappear in the asymptotic parts of the spectral domain MoM impedance matrixand the MoM excitation vector elements for planar grounded dielectric slabs areevaluated in closed-form in this thesis, resulting an improved efficiency and accu-racy for the rigorous investigation of printed antennas. (2) In the space domainMoM solution of printed structures on planar grounded dielectric slabs, an ac-curate way of treating the singularity problem of the self-term and overlappingterms as well as the MoM excitation vector is presented along with a way to halvethe order of space domain integrals by employing a proper change of variablesand analytical evaluation of one of the integrals for each double integral.Finally two different studies which use these improved methods are presentedin order to asses their accuracy and efficiency: (1) Investigation of scan blindnessphenomenon for finite phased arrays of printed dipoles on material coated electri-cally large circular cylinders, and its comparison with the same type of arrays onplanar platforms. In this study effects on the scan blindness mechanism of sev-eral array and supporting structure parameters, including curvature effects, arediscussed. (2) A discrete Fourier transform (DFT) based acceleration algorithmis used in conjunction with the generalized forward backward method (GFBM)ivvto reduce the computational complexity and memory storage requirements of theaforementioned full-wave solution method for the fast analysis of electrically largefinite phased arrays of microstrip patches. As a result both the computationalcomplexity and memory storage requirements are reduced to O(N) (of order N),where N is the number of unknowns.Keywords: Microstrip antennas and antenna arrays, Method of moments, Green?sfunction, Scan blindness.