This paper presents a digital amplitude modulator for a polar transmitter. The instantaneous output power is modulated by adjusting the amplifier's load through a digitally controlled impedance transformation network. The modulator is suited for modulation schemes with moderate peak-to-average power ratio (PAPR), such as π/4 DQPSK The modulator may also be used for fine gain control in constant envelope modulation schemes. A class E amplifier with digital impedance amplitude modulation is integrated in 90nm CMOS. It achieves a peak output power of 9dBm with a PAE of 30% when powered from a 1.2V supply. The measured EVM is 2.6% for a 6dBm π/4 DQPSK modulated signal with 2Mb/s signal rate at 2.4GHz RF frequency. © 2011 IEEE.
Ingels, M., Chironi, V., Debaillie, B., Baschirotto, A., Craninckx, J. (2011). An impedance modulated class-E polar amplifier in 90 nm CMOS. In 7th IEEE Asian Solid-State Circuits Conference, A-SSCC 2011; Jeju; South Korea; 14-16 November 2011 (pp.285-288). IEEE [10.1109/ASSCC.2011.6123567].
An impedance modulated class-E polar amplifier in 90 nm CMOS
BASCHIROTTO, ANDREA;
2011
Abstract
This paper presents a digital amplitude modulator for a polar transmitter. The instantaneous output power is modulated by adjusting the amplifier's load through a digitally controlled impedance transformation network. The modulator is suited for modulation schemes with moderate peak-to-average power ratio (PAPR), such as π/4 DQPSK The modulator may also be used for fine gain control in constant envelope modulation schemes. A class E amplifier with digital impedance amplitude modulation is integrated in 90nm CMOS. It achieves a peak output power of 9dBm with a PAE of 30% when powered from a 1.2V supply. The measured EVM is 2.6% for a 6dBm π/4 DQPSK modulated signal with 2Mb/s signal rate at 2.4GHz RF frequency. © 2011 IEEE.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.