Andrea Vallecchi

Publications (2)0 Total impact

• Conference Proceeding: Entwined spirals for ultra compact wideband frequency selective surfaces

  Andrea Vallecchi, Alex G. Schuchinsky
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  ABSTRACT: The application of a suitable intertwining scheme to planar periodic quadrifilar spiral frequency selective surfaces (FSSs) is shown to dramatically decrease operating frequencies while greatly expanding the bandwidth. At both normal and oblique incidence the proposed intertwined spiral FSSs provide a very sub-wavelength response at wavelengths 40 times larger than the unit cell size. The high packing density of the array ensures the stability of stopband frequency response at oblique incidence. Negligible variations of the resonant frequency are observed for incidence angles up to 45°, and the bandwidth common to TE and TM incidence polarizations is about 40%.
  Antennas and Propagation (EuCAP), 2010 Proceedings of the Fourth European Conference on; 05/2010
• Conference Proceeding: Dual-polarized cylindrically conformal microstrip patch antennas and arrays

  Andrea Vallecchi, Guido Biffi Gentili
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  ABSTRACT: The design of conformal antenna arrays consisting of dual-polarized microstrip patches with a series-type feed mounted on a finite cylindrical ground is addressed. First, we discuss the characteristics of a single dual-polarized cylindrically conformal microstrip patch focusing on the effect of the cylinder curvature on the antenna performance. Then, we present small radius cylindrical arrays made of few conformal patch elements capable of producing either an omnidirectional coverage or sectoral patterns with the radiated field oriented indistinctly along any of two orthogonal polarizations. Preliminary numerical results show that reasonably wide bandwidth operation and good isolation of radiated polarizations can be achieved in both omnidirectional radiation and switched-beam operations.
  Antennas and Propagation (EuCAP), 2010 Proceedings of the Fourth European Conference on; 05/2010