Co-integration of filters and waveguide to microstrip transitions using the foam technology

In this paper, we discuss about original designs of passive structures integrated within a common housing foam material. Milling and pressed moulding techniques are used to produce particular shapes (ridge, cavities,..) then allowing a complete integration and simultaneous association of passive functions (filter, waveguide, microstrip line, polariser..). The foam material is considered either as a supporting structure or as a grooved cavity with internal elements. Experimental as well as simulated results are presented, with original association of volumic and planar functions.