Article

Microstrip antennas integrated with electromagnetic band-gap (EBG) structures: a low mutual coupling design for array applications

Dept. of Electr. Eng., Univ. of California, Los Angeles, CA, USA
IEEE Transactions on Antennas and Propagation (Impact Factor: 2.33). 11/2003; DOI: 10.1109/TAP.2003.817983
Source: IEEE Xplore

ABSTRACT Utilization of electromagnetic band-gap (EBG) structures is becoming attractive in the electromagnetic and antenna community. In this paper, a mushroom-like EBG structure is analyzed using the finite-difference time-domain (FDTD) method. Its band-gap feature of surface-wave suppression is demonstrated by exhibiting the near field distributions of the electromagnetic waves. The mutual coupling of microstrip antennas is parametrically investigated, including both the E and H coupling directions, different substrate thickness, and various dielectric constants. It is observed that the E-plane coupled microstrip antenna array on a thick and high permittivity substrate has a strong mutual coupling due to the pronounced surface waves. Therefore, an EBG structure is inserted between array elements to reduce the mutual coupling. This idea has been verified by both the FDTD simulations and experimental results. As a result, a significant 8 dB mutual coupling reduction is noticed from the measurements.

1 Bookmark
 · 
258 Views
  • [Show abstract] [Hide abstract]
    ABSTRACT: Design consideration of a closely spaced antenna pair with polarization and pattern diversity is presented in this paper. Mutual coupling between the antennas causes pattern distortion and increases cross polarization, and thus it degrades the pattern and polarization diversity and increases the envelope correlation. Two configurations of antenna pair are proposed to examine their mutual coupling and envelope correlation. Each configuration is composed of two perpendicular electrical and magnetic dipoles because, theoretically, it should have higher polarization and pattern diversity. Using two noted formulas of envelope correlation for both configurations, it is found that the values calculated by the two formulas for the same configuration may differ significantly when the antenna pair has larger mutual coupling and cross polarization. Although the calculation of envelope correlation via S-parameters is more time-saving, it is necessary to check the other formula via pattern integration when noticeable amount of mutual coupling exists in a closely spaced antenna pair.
    Antennas and Propagation Society International Symposium (APSURSI), 2012 IEEE; 01/2012
  • [Show abstract] [Hide abstract]
    ABSTRACT: The reduction of mutual coupling between closely spaced antenna elements is attractive in the electromagnetic and antenna community. An efficient approach to suppress the mutual coupling between microstrip patch antennas is proposed using waveguided metamaterials. The waveguided metamaterials are designed and realized by crossed-meander-line slits, which exhibit magnetic resonances and further the band-gap property. By inserting the waveguided metamaterials between two H-plane coupled rectangular patch antennas with the edge-to-edge distance less than $\lambda _{0}/8$, about 6 dB reduction of mutual coupling throughout the $-$10-dB bandwidth has been achieved, which is verified by measurement results.
    IEEE Antennas and Wireless Propagation Letters 01/2012; 11:389-391. · 1.67 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: In this paper, a novel and simple analytical method for analysis of AMC and EBG properties of a typical lossless artificial impedance surface (AIS) is investigated. The main con-tribution of the paper is to demonstrate that AMC and EBG behaviorsof an artificial impedance surface can be characterized analytically with using reflection coefficient for both TE and TM polarized oblique incidence plane waves. It is shown that the AMC properties (when the reflec-tion phase varies in between +90 and −90 degrees) of an impedance surface can be obtained from reflection phase and EBG properties (stop bands for TE and TM surface wave modes) from poles of reflection coefficient. We have derived closed analytical formulas for the impedance surface and reflection coefficient for TE and TM waves for two conventional impedance surfaces such as: grounded dielectric slab and grounded dielectric slab with embedded metallic vias (wired media). The analytical results are verified with numerical simulations.

Full-text

View
10 Downloads
Available from