60 GHz CMOS power amplifier with Psat of 11.4 dBm and PAE of 15.8%

A 60 GHz power amplifier (PA) for a direct-conversion transceiver using standard 90 nm CMOS technology is reported. The PA comprises three cascaded common-source stages with inductive load and inter-stage matching. To increase the saturated output power (P-sat) and power-added efficiency (PAE), the output stage adopts a two-way power dividing and combining architecture. Instead of the area-consumed Wilkinson power divider and combiner, a miniature low-loss LC power divider and a combiner are used. This in turn results in further P-sat and PAE enhancement. Over the 57-64 GHz band of interest, the PA consumes 44.4 mW and achieves a power gain (S-21) of 12.04 +/- 1 dB. At 60 GHz, the PA achieves P-sat of 11.4 mW and a maximum PAE of 15.8%. To the authors' knowledge, this is the best PAE ever reported for a 60 GHz CMOS PA. These results demonstrate the proposed PA architecture is very promising for 60 GHz short-range communication systems.