F. Mira

Fast and accurate analysis and design of substrate integrated waveguide (SIW) filters

This paper describes the application of the boundary integral-resonant mode expansion (BI-RME) method to the accurate modelling of substrate integrated waveguides (SIW). The new formulation fully exploits the particular geometry of this class of structures, thus providing a very efficient analysis method to be used within CAD tools of SIW filters. The advantages of this method have been proved with the successful design of two filters operating in the microwave and millimeter-wave bands.

Efficient CAD of Generalized Coaxial Probes in Rectangular Waveguide using the 3D BI-RME Method

An efficient full-wave method based on the 3D BI-RME (boundary integral-resonant mode expansion) technique for the accurate design of generalized probe-excited rectangular waveguides is presented. The flexibility of the developed CAD tool allows to analyze two common configurations frequently used in modern coaxial-fed microwave devices: conventional and disc-ended coaxial probe excitation. This last configuration is used to drastically improve the electrical response of the classical coaxial probe excitation. Moreover, the influence of the distance from the probe to the waveguide shortcircuit is also discussed, and it is shown that it plays a very important role in the design of probe-excited rectangular waveguides. The proposed approach is fully validated by comparing the obtained numerical results with theoretical and experimental data extracted from the available technical literature

Wideband impedance matrix representation of passive waveguide components based on cascaded planar junctions

[1]xa0A very efficient technique for the full-wave analysis of passive waveguide components, composed of the cascade connection of planar junctions, is presented. This novel technique provides the wideband generalized impedance matrix representation of the whole structure in the form of pole expansions, thus extracting the most expensive computations from the frequency loop. For this purpose, the structure is segmented into planar junctions and uniform waveguide sections, which are characterized in terms of wideband impedance matrices. Then, an efficient iterative algorithm for combining such matrices, and finally providing the wideband generalized impedance matrix of the complete structure, is followed. Two waveguide filters have been used to prove the accuracy and efficiency of this novel technique, which is specially suited for modeling complex geometries.

Efficient Pole Expansion of the Generalized Impedance Matrix Representation for Planar Waveguide Junctions

This paper proposes a novel pole expansion of the generalized impedance matrix representation for planar waveguide junctions. Proceeding in this way, we have obtained a very efficient algorithm for the accurate wideband modelling of such junctions, since the most expensive computations are performed outside the frequency loop. For verification purposes, several practical examples are shown in order to prove the numerical efficiency and accuracy provided by this new technique

Efficient Pole Expansion of the Generalized Admittance Matrix Representation of Planar Waveguide Junctions

In this paper, the fast and accurate wideband modeling of planar waveguide junctions in terms of a generalized admittance matrix representation is addressed. For these purposes, an integral equation technique providing a pole expansion of the cited admittance matrix is outlined, thus widely reducing the frequency dependant operations. A convergence study of this novel algorithm has been first performed, and then it has been successfully applied to the full-wave analysis of a real filter involving planar junctions between rectangular waveguides.

Full-wave analysis of coaxial probes in rectangular waveguide: preliminary results for metal-loaded cavities and coaxial to rectangular waveguide transitions

Coaxial probes are widely used as coupling or feeding elements in a great variety of microwave applications. The paper presents a novel full-wave method for the electromagnetic characterization of a coaxial fed rectangular waveguide. It combines the BI-RME 3D method (Bressan, M. et al., Proc. 32nd European Microwave Conf., 2002) and an efficient integral equation technique (Conciauro, G. et al., Advanced Modal Analysis, John Wiley and Sons, 2000) through a segmentation strategy. The accuracy and computational efficiency of the approach are discussed and the excellent behaviour of the obtained results is observed.

Substrate integrated waveguide hybrid coupler with integrated filter for radar applications

This paper proposes a substrate integrated waveguide (SIW) 180 degrees hybrid coupler with an integrated filter. This device operates at 24.1 GHz for radar applications and the filter removes the frequency of 22.1 GHz coming from the local oscillator. This device is the RF passive part of a single balanced diode mixer. The passive part has been designed, fabricated and measured.