Amado-Rey, A.B.A.B.Amado-ReyCampos-Roca, Y.Y.Campos-RocaWeber, RainerRainerWeberMaroldt, S.S.MaroldtTessmann, AxelAxelTessmannMassler, HermannHermannMasslerWagner, SandrineSandrineWagnerLeuther, ArnulfArnulfLeutherAmbacher, OliverOliverAmbacher2022-03-052022-03-052015https://publica.fraunhofer.de/handle/publica/24330610.1109/LMWC.2015.2496778Five different versions of grounded coplanar waveguide (GCPW) branch-line couplers on GaAs were EM simulated, processed and investigated for operation in G-band (140-220 GHz), based on different layer structures (including 2 or 3 metallization layers) and layouts. The best results have been obtained with the structures based on a continuous galvanic metal in the central conductor line and ohmic connections between top ground planes, reducing the insertion losses by 0.8 dB. A measured amplitude imbalance less than 0.5 dB from 160 to 200 GHz (22%), with a coupler insertion loss lower than 1.3 dB was achieved for a 3 metallization layer branch-line coupler.enbranch-lineelectromagnetic (EM) simulatelectromagnetic simulationgrounded coplanar waveguide (GCPW)hybridmillimeter-wave530journal article