A 28-GHz High Linearity and High Efficiency Class-F Power Amplifier in 90-nm CMOS Process for 5G Communications

A 28-GHz Class-F power amplifier fabricated in 90-nm CMOS process for 5G communications is presented in this paper. This PA is a differential pair topology consisted of two common-source cells. The harmonic-tuned network is constructed to enhance the efficiency. The proposed Class-F PA achieves a 12-dB small-signal gain with 7.4-GHz 3-dB bandwidth (25.1-32.5 GHz), saturated output power (Psat) of 14.9 dBm with 43.8 % peak PAE, and output 1-dB compression point (OP
1dB
) of 14.0 dBm with 42.0 % PAE
1dB
at 28 GHz. With the modulation measured results using the single-carrier 64-QAM signal, this PA achieves 2.1/4.2 Gb/s data rate, 10.6-dBm/8.1-dBm average output power, and 29.5
^%
/22.6
^%
average PAE, while maintaining root-mean-square (rms) error vector magnitude (EVM) better than −25 dB. Among all the published mm-Wave CMOS PAs, this PA shows outstanding large-signal performances and exceptional modulation capability