A Double Layer Substrate Integrated Waveguide Blass Matrix for Beamforming Applications

In this letter, a double layer Blass matrix based on substrate integrated waveguide (SIW) technology is proposed. A prototype of 4 times 16 Blass matrix is implemented, fabricated and measured with SIW slot antennas installed at the output ports. The measured data are in good agreement with the simulated results. At 16.1 GHz, the measured Side Lobe Level of all individual beams is less than -12 dB. Compared with the conventional waveguide construction, this type of Blass matrix possesses the properties of lower cost, easier fabrication and low profile.