The Antenna group has for two decades carried out original research on changing the boundary conditions of a metal conductor by loading its surface by periodic elements. The surface can thus acquire artificial magnetic properties. This work has been published under the terms soft and hard surfaces, using an analogy with acoustics. The soft surfaces are used in, for example, hat-fed reflector antennas for Ericsson’s MINI-LINK product. The hat-fed reflectors have been a product for more than 10 years in the spin-off company Comhat AB which now is part of Arkivator AB.
As a result of this general research we have proposed a new waveguide for millimeter and submillimeter waves, referred to as “Gap waveguide” (patent pending). This technology offers lower losses and lower manufacturing cost than microstrip lines and normal waveguides at high frequency, thus meeting the demand for commercial development of frequencies above 30 GHz. The gap waveguide technology find also advantages as an efficient technology for packaging of microstrip circuits as well as active microwave, mm- and submm-wave circuits and MMICs.
The research is done in collaboration with four other European universities – Siena, Zagreb, Valencia and Carlos III – as well as research groups at Department of microelectronics and nanoscience at Chalmers. Dr. Eva Rajo-Iglesias participates as Aff. prof. from Carlos III Univ., Madrid.
Figure: Examples of gap waveguide components: Filter & two couplers.