Novel multi-layer SIW broadband coupler for Nolen matrix design in Ku band

All the components needed for a 4 times 4 Nolen matrix have been presented for application in multi-layer SIW technology. In particular, a novel 2-layers SIW broad-band coupler has been introduced. The wide coupling dynamic range of this coupler, being stable over a relatively wideband (up to 2 GHz in the Ku-Band), makes it a reliable element for building multiple beam-forming matrix like the one specified. The components can also be of interest for other beam forming networks, like Butler matrices. Moreover, an original low-loss, 2-layers waveguide transition is developed for the realization of such matrices in multi-layers topology in SIW technology. It is expected that these multi-layer components will lead to compact beam forming network topologies. Further investigations are on going, mainly to simulate and realize the foreseen 4x4 Nolen matrix.