Design of W-band coplanar waveguide power amplifier in 0.1μm Gallium arsenide process

The widespread use of modern technologies is fueling demand for faster, more efficient and greater capacity wireless networks for which the millimeter-wave frequency range such as W-band (75-110 GHz) is explored. There are several design challenges in W-band like substantial path loss, atmospheric interference, and poor obstacle penetration. Therefore, at W-band a power amplifier (PA) will play an important role in determining the distance of signal travel. Some microstrip W-band PAs are reported in the literature. However, only a few coplanar waveguide (CPW) based PAs are available in the literature, although in general CPW technique has certain advantages over microstrip lines at high frequencies such as W-band. In this thesis, a W-band CPW amplifier design is targeted. It is noted that the ground planes occupy a large area. To make the size compact, different layout options are explored. A simple CPW line is studied in HFSS. Then different layouts of a simple CPW FET and a Cascode unit cell are investigated in AWR to reduce the circuit size. Finally, a compact CPW amplifier design is presented and its suitability for the W-band application is determined. The designs are implemented in WIN Semiconductor’s 0.1 μm Gallium Arsenide (GaAs) process codenamed PP10-20.