Dual-band predistortion power amplifier for digital cellular and IMT-2000 base-station application

This paper proposes a dual-band predistortion power amplifier using diplexer for digital cellular (f/sub 0/=880MHz) and IMT-2000(f/sub 0/=2140MHz) base station. Each high power amplifier is linearized by using predistortion method. The implemented predistorter uses reflection type IM generator with 3dB hybrid coupler for good reflection characteristic. The diplexer is composed of low pass filter using defected ground structure(DGS) microstrip line and high pass filter using high-Q lumped capacitors and distributed elements. For a forward link one-carrier CDMA IS-95 and WCDMA signal, the proposed dual-band predistortion power amplifier shows ACPR improvement of about 10dBc and 9.36dBc for cellular and IMT-2000 band of operation, respectively.