A Millimeter-Wave Variable-Gain Power Amplifier With $P_{{1,dB}}$ Improvement Technique in 65-nm CMOS

Authors：Luo, Xiongyao; Feng, Wenjie; Zhu, Haoshen; Wu, Liang; Che, Wenquan; Xue, Quan^*

Source：IEEE Microwave and Wireless Components Letters, 2022, 32(12): 1427-1430.

DOI：10.1109/LMWC.2022.3177656

• Gain
• 5G mobile communication
• Wireless communication
• Power generation
• Logic gates
• Frequency measurement
• Transistors
• CMOS
• fifth generation (5G)
• millimeter wave (MMW)
• postdistortion
• variable-gain power amplifier (VGPA)

A millimeter-wave (MMW) variable-gain power amplifier (VGPA) with $P_{{1,dB}}$ improvement technique is proposed. The proposed VGPA consists of a postdistortion power amplifier (PDPA) and a variable-gain amplifier (VGA), for realizing high output power 1-dB compression point ( $P_{{1,dB}})$ and variable gain, respectively. To improve the $P_{{1,dB}}$ performances, a postdistortion technique with peaking-mode gain response shaping is proposed. This new approach has less amplitude-to-amplitude (AM-AM) distortion. Fabricated in 65-nm CMOS process, the proposed VGPA achieves 16-dBm output $P_{{1,dB}}$ with 29.5% power added efficiency (PAE) and 16.7-dBm saturated output power ( $P_{{sat}})$ with 34% peak PAE. The maximum gain reaches 33.1 dB with 3-dB bandwidth from 23.1 to 29 GHz and 31.1-dB dynamic range of gain adjustment.