C-Band Inductive Post SIW alumina filter for a Space Application. Experimental analysis of the thermal behavior

This paper presents a C-Band Inductive Post Substrate Integrated Ceramic Filter for a Space Application. As a strong rejection is needed, it is a 6^th order folded filter in which a cross-coupling is introduced between non adjacent resonators in order to allow the creation of finite transmission zeros. A technique based on a thick film microstrip line approach to realise the cross-coupling was used. The filter proved to be compatible with planar technology through use of specific transitions. The filter was realized on a ceramic substrate (h = 380 μm, εr = 9.9, tanδ = 0.0003) under industrial process. Simulations and measurements over a large range of temperature are presented.