A terahertz on-chip InP-based power combiner designed using coupled-grounded coplanar waveguide lines

This article presents the design and performance of a terahertz on-chip coupled-grounded coplanar waveguide (GCPW) power combiner using a 50 μm-thick InP process. The proposed topology uses two coupled-GCPW lines at the end of the input port to substitute two quarter-wavelength GCPW lines, which is different from the conventional Wilkinson power combiner and can availably minimize the coverage area. According to the results obtained, for the frequency range of 210-250 GHz, the insertion losses for each two-way combiner and four-way combiner were lower than 1.05 dB and 1.35 dB, respectively, and the in-band return losses were better than 11 dB. Moreover, the proposed on-chip GCPW-based combiners achieved a compromise in low-loss, broadband, and small-size, which can find wide applications in terahertz bands, such as power amplifiers and signal distribution networks.