X-band RF switch implementation in substrate integrated waveguide

Thesis Type: Doctorate

Institution Of The Thesis: Orta Doğu Teknik Üniversitesi, Faculty of Engineering, Department of Electrical and Electronics Engineering, Turkey

Approval Date: 2012


Supervisor: ŞİMŞEK DEMİR


An RF switch in substrate integrated waveguide (SIW) technology for X-band is designed and demonstrated. Design is based on embedding shunt pin diodes of the switch in an evanescent mode waveguide filter. At reverse bias, pin diodes formed a part of filter's capacitances. Thus switch also functions as a filter when it is in “on” state. At forward bias of diodes, capacitances of the filter are short circuited to obtain a good isolation. The same circuit structure is used to design a tunable filter and an RF power limiter which also functions as a filter. Several RF functions usually used in RF frontends (power limiting, filtering, switching) are combined in a single circuit which helps miniaturization of the frontend. The circuit can be produced with standard PCB and chip&wire technology. The circuits developed have comparable performances with microstrip counterparts and they are advantageous to use in microwave systems using SIW as the basic transmission medium and need filtering functionality.