SRK 2026

POVZETEK
V tem delu predstavimo eno izmed novejših tehnologij na področju antenske tehnike: valovode z zračno režo. Valovodi z zračno režo so sestavljeni iz enega ali več slojev, ki so lahko tudi ločeni z zračno režo. Njihova posebna značilnost je vodenje elektromagnetnega vala s postavitvijo periodičnih struktur na robu valovoda, ki ustvarijo prepovedano elektromagnetno vrzel in tako preprečujejo uhajanje signala. Zaradi tega je ta tehnologija posebej primerna za frekvence z valovnimi dolžinami v milimetrskem pasu, kjer lahko pri izdelavi prihaja do rež med ploščami. Prvi korak v načrtovanju takih struktur je analiza razširjanja valov v neskončno periodični strukturi. Tako lahko izberemo geometrijo, ki ima zaželeno elektromagnetno vrzel. Naslednji korak je praktična implementacija v končnem valovodu. V predavanju predstavljamo več primerov uporabe z različnimi tehnikami izdelave. Kot primer izpostavljamo valovod za avtomobilski radar, izdelan z zlaganjem tiskanih vezij. Ta metoda proizvodnje je zaradi že uveljavljenega načina izdelave še posebej nizkocenovna. Predstavljen je tudi valovod, izdelan z jedkanjem tankih kovinskih plošč s srebrno prevleko. Tako je celotna struktura popolnoma iz kovine in ima nizke izgube ter sposobnost prenašanja visokih moči zaradi dobrih termičnih lastnosti.

ABSTRACT
In this section, we present one of the newer technologies in the field of antenna engineering: gap waveguides. Gap waveguides consist of one or more layers, which may also be separated by an air gap. Their distinctive feature is the guidance of electromagnetic waves by means of periodic structures placed along the edges of the waveguide, which create an electromagnetic bandgap and thus prevent signal leakage. As a result, this technology is particularly suitable for frequencies with wavelengths in the millimeter-wave band, where gaps between plates may occur during fabrication due to manufacturing tolerances. The first step in designing such structures is the analysis of wave propagation in an infinitely periodic structure. This allows us to select a geometry that exhibits the desired electromagnetic bandgap. The next step is the practical implementation in a finite waveguide. In the lecture, we present several application examples using different manufacturing techniques. As an example, we highlight a waveguide for automotive radar, manufactured by stacking printed circuit boards. Due to the already well-established manufacturing process, this production method is particularly low-cost. Also presented is a waveguide manufactured by etching thin metal plates with a silver coating. In this case, the entire structure is made entirely of metal, resulting in low losses and the capability to handle high power levels due to good thermal properties.