Showing papers by "Per-Simon Kildal published in 1995"
01 Jan 1995
TL;DR: This article has considered the rationale and illustrated the application of model-based parameter estimation (MBPE) to achieve reduced-order representations of electromagnetic observables via fitting models, the model- based part of MBPE, that derive from the physics of EM fields.
74 citations
TL;DR: In this article, a corrugated horn antenna with a 60° half beamwidth was optimized by using a moment method for bodies of revolution (BOV) for broadband feeding of e.g. prime focus reflectors in radio astronomy applications.
Abstract: A compact flare angle controlled corrugated horn antenna with a 60° half beamwidth is optimised by using a moment method for bodies of revolution. The horn has corrugations with simple rectangular cross-sections and is excited by a smooth wall circular waveguide. The resulting 15 dB beamwidth varies by <18% and the crosspolar sidelobe levels are more than 26 dB below the mainlobe, both over a 1.8:1 bandwidth. All results are confirmed by measurements. The horn is suited for broadband feeding of e.g. prime-focus reflectors in radio astronomy applications.
45 citations
18 Jun 1995
TL;DR: In this paper, the authors describe a so called hat antenna which is cheap to manufacture, compact, light-weight and in addition has very low sidelobe performance, and an experimental model with 43 cm reflector diameter has been built and measured at 15 and 30 GHz.
Abstract: Reflector antennas with self supported waveguide feeds of swan-neck type are often used in radio link systems. If there are requirements for very low sidelobes, it is common to attach an absorbing cylinder to the rim of the reflector. Both the cylinder and the feed are expensive to manufacture. The paper describes a so called hat antenna which is cheap to manufacture, compact, light-weight and in addition has very low sidelobe performance. An experimental model with 43 cm reflector diameter has been built and measured at 15 and 30 GHz.
31 citations
TL;DR: In this article, the transmission of electromagnetic fields through corrugated slots is studied for TE and TM polarization, where the corrugations or chokes are optimized in order to make the transmission as low as possible over a given bandwidth.
Abstract: The transmission of electromagnetic fields through corrugated slots is studied for TE and TM polarization. A corrugated slot means that the slot is formed by a gap between two plates and that the edge walls of one or both of these two plates have grooves or corrugations running in the direction of the slot. The field solution is obtained by using the method of moments implemented as a successive inversion of the matrices associated with the unknown E-fields at the apertures between the rectangular regions forming the corrugated slot. The computer code is applied to analyze slots with corrugated edges, where the corrugations or chokes are optimized in order to make the transmission as low as possible over a given bandwidth. The results are verified by comparison with previously published results and measurements on three different slot geometries. >
16 citations
TL;DR: The series solution of the electromagnetic scattering from a circular cylinder with an anisotropic surface impedance due to an arbitrary plane-wave incidence is given in this paper, and the solution can be used as a canonical problem, and for validation of more general numerical methods or for exact calculations of the cylinder with the actual dimension of the realization of the surface impedance.
Abstract: The series solution of the electromagnetic scattering from a circular cylinder with an anisotropic surface impedance due to an arbitrary plane-wave incidence is given The solution can be used as a canonical problem, and for validation of more general numerical methods or for exact calculations of the cylinder with the actual dimension of the realization of the surface impedance Examples are given for verification purposes © 1995 John Wiley & Sons, Inc
2 citations