A P AP R-Aware Dual-Mode Subgigahertz CM OS Power Amplifier for ShortRange Wireless Communication
Abstract: A peak-to-average power ratio (PAPR)-aware dual-mode power amplifier (PA) for short-range wirelesscommunication in the subgigahertz band is proposed in this brief. By carefully choosing the bias, the dual-mode PA achieves the measured output P1 dB (OP1 dB) of 13.6 dBm with a PAE of 25.5%. Furthermore, a dynamic load modulation network is utilized to optimize the PA's efficiency at back-off power. A power-control loop is proposed to detect the input signal PAPR in real time and flexibly reconfigure the PA's operation modes. With these proposed techniques, the PAE has been improved by Ă—2.61 at 7-dB back-off power. The measurement shows that the subgigahertz-band PA archives an adjacent channel leakage ratio (ACLR1) of -37.3 dBc and an average/peak error vector magnitude of -30.4 dB/-20.5 dB at 8.9-dBm output power for ~5-dB-PAPR 16-quadraturemagnitude-modulation LTE signals with 5-MHz bandwidth with the power control loop enabled. The PAPR-aware dual-mode PA, powered by a 2-V supply, occupies a 2.52-mm2 die area in a 180-nm CMOS.