A Compact Transformer-Based E-Band CMOS Power Amplifier with Enhanced Efficiencies of 15.6% PAE1dB and 6.5% PAE at 6 dB Power Back-Off

Abstract

This paper presents a compact E-band power amplifier (PA) implemented in a 40 nm CMOS process. The neutralization technique is adopted to improve reverse isolation, stability and power gain. The linearity of the PA is improved by operating the output stage in the deep class-AB region. Transformer-based matching networks (TMNs) are used for impedance transformation, and optimized for output power and efficiency. At 81 GHz, the presented PA achieves a maximum output 1 dB compressed power (P1dB) of 11.2 dBm and a saturated output power (Psat) of 12.7 dBm with 1 V supply. The power-added efficiencies at P1dB (PAE1dB) and 6 dB power back-off (PBO) are 15.6% and 6.5%, respectively.