A transformer-based CMOS power amplifier （PA） is linearized using an analog predistortion technique for a 2.5-GHz m-WiMAX transmitter. The third harmonic of the power stage and driver stage can be cancelled out in a...A transformer-based CMOS power amplifier （PA） is linearized using an analog predistortion technique for a 2.5-GHz m-WiMAX transmitter. The third harmonic of the power stage and driver stage can be cancelled out in a specific power region. The two-stage PA fabricated in a standard 0.18-#m CMOS process delivers 27.5 dBm with 27% PAE at the 1-dB compression point （PldB） and offers 21 dB gain. The PA achieves 5.5 % EVM and meets the spectrum mask at 20.5 dBm average power. Another conventional PA with a zero-cross-point of gm3 bias is also fabricated and compared to prove its good linearity and efficiency.展开更多
This paper describes a new approach for designing analog predistorters that can compensate for the nonlinear distortion of laser drivers in a radio-over-fiber （RoF） system. In contrast to previous works, this paper ...This paper describes a new approach for designing analog predistorters that can compensate for the nonlinear distortion of laser drivers in a radio-over-fiber （RoF） system. In contrast to previous works, this paper analyzes the transfer characteristics of CMOS transistors, by combining parallel currents of CMOS transistors in various W/L and negative bias voltages to realize the tunable analog predistortion function. The circuit is fabricated by a standard 0.18txm CMOS technology. The core circuit current consumption is only 15mA and the entire driver circuit works in a band-pass from 1 - 2.2GHz. Experimental results of two-tone tests have shown that with an analog predistortoer the IIP3 of the laser driver circuit has an improvement of 4.91 dB.展开更多
文摘A transformer-based CMOS power amplifier （PA） is linearized using an analog predistortion technique for a 2.5-GHz m-WiMAX transmitter. The third harmonic of the power stage and driver stage can be cancelled out in a specific power region. The two-stage PA fabricated in a standard 0.18-#m CMOS process delivers 27.5 dBm with 27% PAE at the 1-dB compression point （PldB） and offers 21 dB gain. The PA achieves 5.5 % EVM and meets the spectrum mask at 20.5 dBm average power. Another conventional PA with a zero-cross-point of gm3 bias is also fabricated and compared to prove its good linearity and efficiency.
基金Supported by the National Natural Science Foundation of China(No.61036002)
文摘This paper describes a new approach for designing analog predistorters that can compensate for the nonlinear distortion of laser drivers in a radio-over-fiber （RoF） system. In contrast to previous works, this paper analyzes the transfer characteristics of CMOS transistors, by combining parallel currents of CMOS transistors in various W/L and negative bias voltages to realize the tunable analog predistortion function. The circuit is fabricated by a standard 0.18txm CMOS technology. The core circuit current consumption is only 15mA and the entire driver circuit works in a band-pass from 1 - 2.2GHz. Experimental results of two-tone tests have shown that with an analog predistortoer the IIP3 of the laser driver circuit has an improvement of 4.91 dB.
