A New Miniaturized Type of Three-Dimensional SiGe 90° Hybrid Coupler at 20 GHz using The Meandering TFMS and Stripline Shunt Stub Loading

This paper proposes a new scheme for realizing a compact 3-D 90deg hybrid coupler based on the compact meandered thin-film microstrip (TFMS) transmission line and stripline shunt stub loading, and successfully demonstrated by using the multi-layer 0.35 mum SiGe HBT Jazz process. The proposed coupler takes advantage of the multi-level metallization processes offered in SiGe technology. The intrinsic area of the fabricated 3-D hybrid coupler is significantly reduced and has shown a size reduction of 92% in circuit area at 20 GHz compared to that of a conventional hybrid coupler using the TFMS configuration. Experimental results are presented in support of the novel miniature coupler.