Slot radiator with tuning vias for circularly polarized SIW linear array

A 16-element circularly polarized (CP) Substrate Integrated Waveguide (SIW) linear array antenna with -26 dB Taylor distribution and 2% residue power at 17 GHz is designed. The single element consists of four crossed inclined radiating slots. In this configuration, reflection goals on the linear array are not fully achieved. For this reason a tuning element is included on some of the individual radiating elements, which consists of a pair of metallic vias that greatly enhances the reflection of longest slots. Therefore, the antenna reflection is also improved. A global antenna prototype is manufacture to check the new slot element performance in an array configuration. The specified operation band is 16.3 to 17.7 GHz.