A 24GHz, +14.5dBm fully-integrated power amplifier with 50Q input and output matching is fabricated using 0.18pm CMOS transistors. To enable this, a shielded-substrate coplanar waveguide transmission line structure is used to achieve low loss and small area. The power amplifier achieves a power gain of 7dB and a maximum single-ended output power of +14.5dBm with a 3dB bandwidth of 3.1GHz, while drawing lOOmA from a 2.8V supply. The chip area is 1.26mm2.