Detail-Oriented Design of a Dual-Mode Antenna with Orthogonal Radiation Patterns Utilizing Theory of Characteristic Modes
Keywords:
Dual-mode antenna, method of moments (MoM), theory of characteristic modes (TCMs)Abstract
In this paper, theory of characteristic modes (TCMs) is used to perform modal analysis of a trapezium-shaped PEC plate. So it follows that a wide-spread overview about the electromagnetics behavior of the plate is provided. The first seven characteristic currents and corresponding resonance frequencies of the structure are obtained. All modes are orthogonal to each other. By applying the reactive loading, the first two modes are forced to be resonating close to each other at frequency of about 3.5 GHz, which is suitable for WiMax applications. To excite aforementioned modes on the structure, an appropriate configuration of microstrip feed lines is utilized. Due to the orthogonality property of current modes, the created radiation patterns are also orthogonal to each other. Since two characteristic currents are excited on the structure’s body, it is expected to achieve two orthogonal radiation patterns too, which could result in a dual-mode antenna. To carry out the above-mentioned modal analysis, a specific method of moments (MoM) code has been developed and applied. The proposed antenna is simulated by well-known full-wave package Ansoft HFSS and results clarification of the expectations about the orthogonality in patterns.
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References
D. Pozar, Microwave Engineering, John Wiely and Sons, 2005.
M. Swillam, M. Bakr, and X. Li, “Modal sensitivity analysis of guided wave structures using one FDTD simulation,” 25th Annual Review of Progress in Applied Computational Electromagnetics (ACES), pp. 286-290, Mar. 2009.
R. Harrington, “Effect of antenna size on gain, bandwidth and efficiency,” J. Res. Nat. Bur. Stand. Radio Propag., vol. 64, pp. 1-12, Jan. 1960.
D. Wilton and R. Mittra, “A new numerical approach to the calculation of electromagnetic scattering properties of two dimensional bodies of arbitrary cross section,” IEEE Trans. Antennas Propag., vol. 20, no. 2, pp. 310-317, May 1972.
R. Harrington and J. Mautz, “Theory of characteristic modes for conducting bodies,” IEEE Trans. Antennas Propag., vol. 19, no. 5, pp. 622- 628, Sep. 1971.
R. Harrington and J. Mautz, “Computation of characteristic modes for conducting bodies,” IEEE Trans. Antennas Propag., vol. 19, no. 5, pp. 629- 639, Sep. 1971.
E. Antonino-Daviu, M. Cabedo-Fabres, M. Gallo, M. Ferrando-Bataller, and M. Bozzeti, “Design of a multimode MIMO antenna using characteristic modes,” in Proc. 3rd EuCAP, 2009, pp. 1840- 1844.
A. Araghi and G. Dadashzadeh, “Oriented design of an antenna for MIMO applications using theory of characteristic modes,” IEEE Antennas and Wireless Propag. Letters, vol. 11, pp. 1040-1043, Sep. 2012.
R. Harrington and J. Mautz, “Control of radar scattering by reactive loading,” IEEE Trans. Antennas Propag., vol. 20, no. 4, pp. 446-454, July 1972.
R. Harrington, Field Computation by Moment Method, New York: Macmillan, 1968.
E. Newman, “Small antenna location synthesis using characteristic modes,” IEEE Trans. Antennas Propag., vol. 27, no. 4, pp. 622-628, July 1979.
M. Cabedo-Fabres and A. Valero-Nogueira, “Systematic design of antennas using the theory of characteristic modes,” Ph.D. dissertation, Univ. Politec. Valencia, Valencia, Spain, 2007.
S. Rao, D. Wilton, and A. Glisson, “Electromagnetic scattering by surfaces of arbitrary shape,” IEEE Trans. Antennas Propag., vol. 30, no. 3, pp. 409-418, May 1982.
M. Cabedo-Fabres, E. Antonino-Daviu, A. ValeroNogueira, and M. Ferrando-Bataller, “The theory of characteristic modes revisited: A contribution to the design of antennas for modern applications,” IEEE Antennas Propag. Mag., vol. 49, no. 5, pp. 52-68, Oct. 2007.
