Near Field Analysis of the Modal Scattering at Radiating Apertures
Source: AEÜ International Journal of Electronics and Communications, Volume 55, Number 5, October 2001 , pp. 355-362(8)
Publisher: Urban & Fischer
A rigorous method for the determination of the modal scattering at radiating apertures is presented. Near-field boundary conditions to be satisfied on the outer surface of the conducting structure containing the aperture (e.g. a horn antenna) are completely taken into account. The resulting scattering matrix of the radiating aperture can be integrated into any mode-matching technique as a termination for the cascaded structure commonly used to match the aperture to the exciting waveguide. The method is based on a multiple-multipole expansion of the electromagnetic field outside the radiating object in conjunction with a point-matching technique. Horn antennas with elliptical and circular apertures have been analyzed using the suggested method. Excellent agreement with measurement results has been achieved for both the radiation pattern and the aperture scattering parameters.
Keywords: Waveguide radiators; Horn antennas; Near field analysis; Far field analysis; Scattering at apertures; Radiation from apertures; Mode-matching method; Multiple multipole method; Point-matching method
Document Type: Original article
Publication date: 2001-10-01