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Anil Pandey : Electronics Design and Simulations

Printed Conformal Antennas Design

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In many applications pertaining to missile, satellite, spacecraft and aircraft a directive antenna mounted on a curved body is required. Conforming the antenna to the surface save space and is often essential for structural reasons. An antenna that conforms to a surface whose shape is determined by considerations other than electromagnetic; for example, aerodynamic or hydrodynamic called conformal Antenna. Microstrip antenna technology is most suitable for conformal applications because of their ability to conform to non-planar structures. Microstrip antenna patches are placed above what may be characterized as a conducting plane with a dielectric substrate separating the patch from the conducting plane. The properties of such an array depend strongly on whether it is small compared to the radius of curvature of mounting body, in which case it behaves nearly like a planner array or whether it is comparable or large to the radius.

Conformal antenna may be put in the belly of aircraft then there is no need of radome. Besides this, shaping and resolution can be improved by using conformal antenna as more elements can be accommodated. In conformal antenna it is found that resonance frequency is same for various curvatures. However as curvature increases the pattern broadens. The aperture design of the conformal array is predicted on the knowledge of the patterns and coupling coefficients in the mutual coupling environment. The analysis and synthesis of conformal array is slightly more complicated than linear array with uniform spacing because the array elements point in different directions.

Updated 3rd October 2018 at 07:42 by anilkrpandey

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  1. asgant's Avatar
    hii anil.
    i have done conformal patch antenna.first i designed in rectangular shape and the gain is 6 dB.returnloss was also good..after that i wraped it on a cylinder.but the gain im getting is -5 dB.the returnloss got degraded.can i know the reason for that.
  2. anilkrpandey's Avatar
    Hi Asgant,

    It's quite possible. Usually, these antennas are designed assuming a planar surface. A characteristic phenomenon of patch antennas conformal to curved platforms is the dependence of resonant input impedance on surface curvature.Understanding how surface curvature affects the input impedance and resonant frequency is crucial for matching with the feed network and efficient radiation.This is especially important for highly resonant antennas, such as patches, due to their narrow bandwidth. The physical effects of surface curvature are introduced into the model in the boundary integral term by means of a specially formulated dyadic Green’s function in numerical analysis.