Multi-dimensional substrate integrated waveguide for high density integration

This paper analyses the main configuration of the substrate integrated waveguide (SIW) allowing spatial arrangement and miniaturization. With the increasing performance demand on wireless systems, high-density millimeter-wave system integration techniques have been under intense development. The performance of the guided-wave structure is crucial for the design of millimeter and sub-millimeter systems. Following the appearance of SIW, many researchers worked to develop an improvement of the standard version. The main known configurations of SIW: half mode SIW, folded C-type SIW, ridge SIW, E-plane SIW and folded L-type SIW are summarized in this paper. The losses and propagation constant are compared. The proposed configurations don´t allow only spatial arrangement and miniaturization but also the control of other characteristics like bandwidth, loss and impedance. To illustrate the advantages and flexibility of these lines, four structures feed by this type of lines are presented.