Ultra-compact X-band SIW filter in LTCC technology using high permittivity substrate for a space application

Substrate Integrated Waveguide (SIW) provides a better Q-factor compared with the other planar techniques. Its integration capabilities and fabrication cost are other benefits that make it attractive. But SIW filters are bulkier than their equivalents achieved in microstrip technology. This paper reports on the association of two solutions to reduce size and make SIW even more attractive: LTCC technology to stack cavities and high permittivity substrate. The objective is to demonstrate the possibility to build high performance X-band filter on a ceramics through a multi-layer approach. The solution is tested on a X-band-dedicated 6th-order filter with drastic specifications for space application.