Specteral Domain Analysis of Resonant Characteristics and Radiation Patterns of a Circular Disk and Annular Ring Microstrip Antenna on Uniaxial Substrate

Abstract

Abstract-A full-wave analysis for determining the resonant frequency, quality factor and far-zone radiation patterns of a circular disk and annular ring microstrip patches, printed on a uniaxial anisotropic substrate is presented. Green's functions of the structure are determined in Hankel transform domain (HTD) using Hertz potential vectors. Galerkin's method, together with parsval's relation in Hankel transform domain is then applied to compute the resonant frequency and quality factor. The far-zone radiation patterns are expressed in terms of Hankel transforms of the tangential fields on the substrate. Wave equation is solved in cylindrical coordinates for the structure to estimate the basis function. The numerical results show that there are substantial deviations in calculated resonant frequency and quality factor when substrate dielectric anisotropy is considered. Furthermore, significant variations are seen in the radiation patterns of the structures due to substrate anisotropy. The variations of resonant frequency, quality factor and radiation patterns of the structure, with respect to anisotropy ratio of the substrate, for several values of substrate thickness and patch radius are presented.

Full-Wave Analysis of Anisotropic Circular Microstrip Antenna With Air Gap Layer

“…Experimental and numerical evaluations have been performed with a patch for different radius a, printed on single substrate (d 1 = 0) with relative permittivity ε r = 2.43 and thickness d 2 = 0.49 mm. Table 1 summarizes our computed resonant frequencies and those obtained for TM 11 mode via spectral domain formulation [18][19][20]. The comparisons show a good agreement between our results and those of literature [18][19][20].…”

“…Table 1 summarizes our computed resonant frequencies and those obtained for TM 11 mode via spectral domain formulation [18][19][20]. The comparisons show a good agreement between our results and those of literature [18][19][20]. In order to check the accuracy of the spectral domain method described in the previous section for two-layered case, our results are compared with an experimental and theoretical values presented in the previous work [19].…”

“…In order to confirm the computation accuracy of the spectral domain approach, our results are compared with experimental and recent theoretical data [18][19][20]. Experimental and numerical evaluations have been performed with a patch for different radius a, printed on single substrate (d 1 = 0) with relative permittivity ε r = 2.43 and thickness d 2 = 0.49 mm.…”

Theoretical Study of Superconducting Annular Ring Microstrip Antenna With Several Dielectric Layers

“…By substituting (18) into (19), vector Hankel transform of the current basis functions can be given by…”

“…However, the accuracy of these approximate models is limited and only suitable for analysing simple, regularly shaped antenna or thin substrates. The full-wave spectral domain technique is extensively used in microstrip analysis and design [18][19][20][21]. This method gives better results than approximate techniques.…”