Linear Transmitter Architecture Using BAW Filter

A bulk acoustic wave filter, which can be used in EDGE transmitter, is presented in this paper. It attenuates power amplifier harmonic frequencies and out-of-band noise generated by sigma-delta modulator needed in linear architecture. This filter achieves 2.4 dB insertion loss including matching network to 50 Omega and more than 15 dB of return loss. Power handling capability and linearity performance of bulk acoustic wave devices are detailed and satisfy to power application requirements. Antenna mismatch effect has been evaluated using an active load-pull bench. This filter is connected in series to power amplifier to form a prototype of power amplifier module for GSM/EDGE standard in the DCS frequency band. The power amplifier is realized using STMicroelectronics 0.25 mum BiCMOS technology