volume | PIER Journals

Abstract

Rigorous mathematical Method of Moments (MoMs) for analyzing various radiating spherical structures is presented in this paper by using Dyadic Green's Functions (DGFs) in conjunction with Mixed Potential Integral Equation (MPIE) formulation. With the aid of linear Rao-Wilton-Glisson (RWG) triangular basis functions and by converting spherical DGFs to Cartesian DGFs, a conformal dipole antenna in free space and over a Perfect Electric Conductor (PEC) sphere is analyzed. The characteristics of such antennas are computed by applying multilayer spherical DGFs and asymptotic approximation methods. Mutual couplings between elements of a conformal dipole antenna array in free space and over a conducting sphere are also investigated. Good agreement between the computational results obtained by the proposed methods and those obtained from commercial simulator packages shows accuracy and high convergence speed of the presented methods.

1. Chew, W. C., Waves and Fields in Inhomogeneous Media, IEEE Press Series on Electromagnetic Waves, 1995.

2. Tai, C. T., Dyadic Green's Functions in Electromagnetics Theory, IEEE Press Series on Electromagnetic Waves, 1994.

3. Okhmatovsk, V. I. and A. C. Cangellaris, "Efficient calculation of the electromagnetic dyadic Green's function in spherical layered media," IEEE Trans. Antennas Propag., Vol. 51, No. 12, 3209-3220, Dec. 2003.
doi:10.1109/TAP.2003.820952 Google Scholar

4. He, M. and X. Xu, "Closed-form solutions for analysis of cylindrically conformal microstrip antennas with arbitrary radii," IEEE Trans. Antennas Propag., Vol. 53, No. 1, 518-525, Jan. 2005.
doi:10.1109/TAP.2004.838772 Google Scholar

5. Tam, W. Y. and K. M. Luk, "Resonance in spherical-circular microstrip structures," IEEE Trans. Microw. Theory Tech., Vol. 39, No. 4, 700-704, Apr. 1991.
doi:10.1109/22.76435 Google Scholar

6. Huia, H. T. and E. K. N. Yungb, "Dyadic Green's functions of a spherical cavity filled with a Chiral medium," Journal of Electromagnetic Waves and Applications, Vol. 15, No. 9, 1229-1229, 2001.
doi:10.1163/156939301X01138 Google Scholar

7. Khamas, S. K., "Asymptotic extraction approach for antennas in a multilayered spherical media," IEEE Trans. Antennas Propag., Vol. 58, No. 3, 1003-1008, Mar. 2010.
doi:10.1109/TAP.2009.2039333 Google Scholar

8. Li, L. W., P. S. Kooi, M. S. Leong, and T. S. Yeo, "Electromagnetic dyadic Green's function in spherically multilayered media," IEEE Trans. Microw. Theory Tech., Vol. 42, 2302-2310, Dec. 1994. Google Scholar

9. Macon, C. A., K. D. Trott, and L. C. Kempel, "A practical approach to modeling doubly curved conformal microstrip antennas," Progress In Electromagnetics Research, Vol. 40, 295-314, 2003.
doi:10.2528/PIER02122903 Google Scholar

10. Arakakia, D. Y., D. H. Wernerb, and R. Mittrac, "A technique for analyzing radiation from conformal antennas mounted on arbitrarily-shaped conducting bodies," Journal of Electromagnetic Waves and Applications, Vol. 14, No. 11, 1505-1523, 2000.
doi:10.1163/156939300X00266 Google Scholar

11. Gibson, W. C., The Method of Moments in Electromagnetics, Chapman & Hall/CRC, Taylor & Francis Group, 2008.

12. Rao, S. M., D. R. Wilton, and A. W. Glisson, "Electromagnetic scattering by surfaces of arbitrary shape," IEEE Trans. Antennas Propag., Vol. 30, 409-418, May 1982.
doi:10.1109/TAP.1982.1142818 Google Scholar

13. Harrington, R. F., Field Computation by Moment Methods, IEEE Press Series on Electromagnetic Waves, 1991.

14. Khamas, S. K., "Electromagnetic radiation by antennas of arbitrary shape in a layered spherical media," IEEE Trans. Antennas Propag., Vol. 57, No. 12, 3827-383, Dec. 2009.
doi:10.1109/TAP.2009.2033444 Google Scholar

15. Harrington, R. F., Time-Harmonic Electromagnetic Fields, IEEE Press, John Wiley & Sons, Inc., 2001.
doi:10.1109/9780470546710

16. Pozar, D. M., "Microwave Engineering," John Wiley & Sons, Inc., Vol. 3rd, 2005. Google Scholar

17. "CST Reference Manual,", Computer Simulation Technology, Darmstadt, Germany, 2008. Google Scholar

18. Hansen, R. C., Geometrical Theory of Diffraction, IEEE Press, 1981.

Dr. Javad Soleiman-Meiguni

Dr. Manouchehr Kamyab

Dr. Ahmad Hosseinbeig