Analysis of 4-way divider MMICs in GaAs technology for H-band applications

A 4-way Wilkinson and a 4:1 Dolph-Chebyshev divider MMIC based on grounded coplanar waveguide technology on GaAs are presented, analyzed and compared. The Dolph-Chebyshev structure was simulated by using electromagnetic software, whereas the 4-way Wilkinson divider was simulated by a schematic CAD tool. Both dividers are processed and experimentally evaluated for operation in H-band (220-330 GHz). The 4-way Wilkinson MMIC achieves the best insertion losses, which are lower than 107 dB between 235 and 255 GHz (8 2 % of relative bandwidth, RBW). Input return losses better than 12 dB, an amplitude imbalance between outer and inner branches lower than 0.7 dB and a phase difference of (1.5 ± 0.1)° is achieved by the Dolph-Chebyshev from 235 to 257 GHz (RBW=8.9 %). The 4-way Wilkinson divider is very compact with a size of 0.09 × 0.22 mm
²
.