A micro compact coplanar power divider at X-band with finite-width ground plane based on GaAs MMIC technology

A micro coplanar Wilkinson power divider at X-band on GaAs substrate is presented in this paper. The proposed power divider introduces a size reduction method, and the length of the transmission line is reduced to λ/8 (at 10 GHz). Since the two segments of the two edge coupled quarter-wave asymmetric coplanar striplines (ACPSs) with finite-width ground plane are closed to each other, their characteristic parameters, such as characteristic impedance and attenuation coefficient, are obtained using the quasi-static conformal mapping technique (CMT) of coupled coplanar waveguide (CCPW) with finite-width ground plane. S-parameters for the power divider are deduced in the case of quasi-static TEM even–odd mode. The fabrication process is compatible with the GaAs MMIC process. The measured S-parameters are compared with the simulated results of HFSS v.11 and the calculated results of TEM even–odd analysis. Simulated results show that it has reflection loss less of 16.5 dB and insertion loss less of 3.6 dB. Measured results show that the divider has reflection loss less of 15.0 dB and insertion loss less of 3.5 dB. Compared with conventional Wilkinson power divider, the length of the power divider is shortened from 2,620 to 1,570 μm.