An 84 GHz DAT-based power amplifier with 18 dBm P_sat utilizing an ultra-symmetric dual-differential power divider

An ultra-symmetric dual-differential power divider based on the low loss CPW and transformer for the distributed active transformer (DAT) based power amplifiers (PA) has been introduced in this Letter. Two millimeter-wave PAs with different power dividers are compared. Experimental results show that the PA2 with the proposed power divider achieves 18 dBm saturated output power (Psat) at 84 GHz, which exceeds that of the PA1 with the typical dual-differential power divider by 1.35 dB. The power gain and power-added efficiency (PAE) of PA2 are 24.4 dB and 12.63%, respectively. The PA2 occupies a die area of 0.48 mm2.