Abstract
Abstract The quadrature power amplifier (QPA) is used in a CMOS radio frequencies (RF) amplifier for wireless communication system such as WLAN and mobile communication(W-CDMA).Because of its high efficiency at high frequency operation and good linearity.This paper presents a design and analysis in the timeand frequency domains for quadrature power amplifier based on 90-nm CMOS technology.The Class D power amplifier is used in the QPA configuration, because ofthe switch mode amplifiers provide amplification for modulated signals at RF with high efficiency and linearity. The quadrature signals are to be directly amplified by using a QPA without decomposing these signal to a phase and amplitude signal because of the lack of its separate avoid and the linearity and bandwidth requirements, thus reducing power consumption. The results obtained show that the QPA can be used in a wide band spectrum. The amplifier has very good power added efficiency (PAE%) about (70.5%)and IDM3 is (-62.6dBm) at maximum output power (24.35dBm) and input power greater than (20dBm). The amplitude distortionhas been obtained in this work about (1.36 dB/dB), and phase distortion about(0.27 degree/dB).
