Radiation efficiency and surface waves for patch antennas on inhomogeneous substrat

In this paper the surface wave characteristics, as well as the radiation efficiency and the directivity of a patch antenna, with a given current distribution, located on top of an inhomogeneous, isotropic substrate are calculated. The substrate is infinite in the lateral directions and inhomogeneous with respect to the height coordinate. The surface waves in the substrate are analyzed using the propagator technique and residue calculus. The propagators and the residues are found by solving two sets of systems of ordinary differential equations (ODEs). Several dispersion curves of the surface waves for inhomogeneous substrates are calculated. The radiation efficiency and the directivity are compared with the corresponding quantities of a printed antenna on a homogenized substrate. Moreover, some alternative ways of calculating the reflection dyadic of an inhomogeneous substrate are presented in a series of appendices. (Less)

[1]  S. Long,et al.  Resonant frequency of a circular disc, printed-circuit antenna , 1977 .

[2]  Guy A. E. Vandenbosch,et al.  Study of gain enhancement method for microstrip antennas using moment method , 1995 .

[3]  Alessandro Toscano,et al.  Full-wave analysis of planar stratified media with inhomogeneous layers , 2000 .

[4]  L. Felsen,et al.  Radiation and scattering of waves , 1972 .

[5]  D. Rutledge,et al.  Substrate Optimization for Integrated Circuit Antennas , 1982, 1982 IEEE MTT-S International Microwave Symposium Digest.

[6]  Johnson J. H. Wang Generalized Moment Methods in Electromagnetics: Formulation and Computer Solution of Integral Equations , 1991 .

[7]  A. Derneryd,et al.  Analysis of the microstrip disk antenna element , 1979 .

[8]  R. Boix,et al.  Resonant modes of circular microstrip patches over ground planes with circular apertures in multilayered substrates containing anisotropic and ferrite materials , 2000 .

[9]  Scattering from a frequency selective surface supported by a bianisotropic substrate , 2000 .

[10]  W. Chew,et al.  Resonance of nonaxial symmetric modes in circular microstrip disk antenna , 1980 .

[11]  Stuart A. Long,et al.  Theory of the circular-disc printed-circuit antenna , 1978 .

[12]  David M. Pozar,et al.  Rigorous closed-form expressions for the surface wave loss of printed antennas , 1990 .

[13]  Y. Lo,et al.  Theory and experiment on microstrip antennas , 1979 .

[14]  E.D. Denman,et al.  An introduction to invariant imbedding , 1977, Proceedings of the IEEE.

[15]  J. Watkins,et al.  Circular resonant structures in microstrip , 1969 .

[16]  Gerhard Kristensson,et al.  Propagation in bianisotropic media - reflection and transmission , 2001 .

[17]  G. Kristensson,et al.  Homogenization of woven materials , 1998 .

[18]  Radiation modes in circular patch antennas , 1994 .

[19]  A. K. Bhattacharyya Characteristics of space and surface waves in a multilayered structure (microstrip antennas) , 1990 .

[20]  Nirod K. Das,et al.  A Generalized Spectral-Domain Green's Function for Multilayer Dielectric Substrates with Application to Multilayer Transmission Lines , 1987 .

[21]  R. Bansal,et al.  Antenna theory , 1983, IEEE Antennas and Propagation Society Newsletter.

[22]  W. Chew Waves and Fields in Inhomogeneous Media , 1990 .

[23]  Alessandro Toscano,et al.  Microstrip Disk Antennas With Inhomogeneous Artificial Dielectrics , 2000 .

[24]  R. Collin Field theory of guided waves , 1960 .

[25]  Henry C. Thacher,et al.  Applied and Computational Complex Analysis. , 1988 .

[26]  R. Kaul,et al.  Microwave engineering , 1989, IEEE Potentials.

[27]  V. Losada,et al.  Resonant modes of circular microstrip patches in multilayered substrates , 1999 .

[28]  Guy A. E. Vandenbosch,et al.  Effect of superstrate on radiated field of probe fed microstrip patch antenna , 2001 .

[29]  J. Roebuck,et al.  Waves in layered media , 1981 .

[30]  Editors , 1986, Brain Research Bulletin.

[31]  W. Chew,et al.  Resonance of the axial-symmetric modes in microstrip disk resonators , 1980 .

[32]  R. Collin Antennas and Radiowave Propagation , 1985 .

[33]  H. J. Hagger,et al.  Electromagnetic Waves in Stratified Media , 1996 .

[34]  Gerhard Kristensson,et al.  Propagators and scattering of electromagnetic waves in planar bianisotropic slabs - an application to frequency selective structures , 2001 .

[35]  R. Boix,et al.  Full-wave analysis of circular microstrip resonators in multilayered media containing uniaxial anisotropic dielectrics, magnetized ferrites, and chiral materials , 2000 .

[36]  A. Giarola,et al.  Microstrip disk antennas, Part I: Efficiency of space wave launching , 1984 .

[37]  D. M. Kokotoff,et al.  On improving the surface wave efficiency of microstrip patches , 1997, IEEE Antennas and Propagation Society International Symposium 1997. Digest.

[38]  Radiation by an aperture antenna of arbitrary shape , 2000 .

[39]  Sailing He,et al.  Time domain wave-splittings and inverse problems , 1998 .

[40]  W. Y. Tam,et al.  Analysis of circular microstrip antennas with superstrate , 1989 .

[41]  Irene A. Stegun,et al.  Handbook of Mathematical Functions. , 1966 .