Dual‐layer frequency beam‐scanning antennas without specifically designed radiation elements by using tile‐configured power‐dividers

Abstract

In this article, two dual‐layer frequency beam‐scanning antennas (FBSAs) without specifically designed radiation elements are proposed. For the realization of such FBSAs, two tile‐configured stripline power‐dividers with in‐phase outputs are designed. These power‐dividers enable conventional radiation elements such as the Yagi‐Uda antenna to be usable in a FBSA with the dual‐layer configuration, and therefore reduce the complexity of the overall array that is one major issue in our previous work. In the first design, the input of the array is constructed by a bilateral broadside‐coupled suspended stripline (BBSS). Specific substrate thickness is required for the connection between an SMA and the BBSS and therefore, an improvement is conducted by using a proposed broadside‐connected double‐layer coplanar waveguide (BD‐CPW) as the input. For both power‐dividers, the insertion loss is smaller than 0.25 dB, together with a phase imbalance smaller than 1°. For validation, two 20‐element FBSAs centered at 8.75 GHz with Yagi‐Uda radiation elements are designed, fabricated, and also verified in the measurement.