A fourth-order CMOS bandpass amplifier with high linearity and high image rejection for GSM receivers

A fourth-order CMOS bandpass amplifier with improved linearity and image rejection using standard CMOS 0.8 /spl mu/m technology is presented. Sources of nonlinearities in the bandpass amplifier are discussed, and linearized tuning circuits are designed. With a quality factor of 38, the overall voltage gain and the image rejection are 28 dB and 36.5 dB respectively. Also, the corresponding noise figure is 5.8 dB. Simulated with the improved tuning circuitries, the IIP/sub 3/ is -18 dBm and the P/sub o-1 dB/ are -18 dBm and -31.5 dBm respectively. The total current dissipation is 32 mA.