Tunable bulk acoustic wave filters using active inductors

Abstract

Many ways of reconfiguring Bulk Acoustic Wave-Solidly Mounted (BAW-SMR) filters are applied nowadays. Some of them are using passive components, others use RFMEMS, and others use capacitors controlled by decoder or MOS transistors. To overcome the problems of the passive inductors used to reconfigure this type of filters, this thesis will present a new technology of reconfiguring BAW-SMR filters by adding active inductors to the shunt resonators. The tunable BAW-SMR filter is realized in a ladder topology used for WLAN 802.11 b/g standard (2.40 – 2.48 GHz). Based on the proposed structure, a prototype active filter is designed and simulated in a 0.18u CMOS technology. Simulation of the overall circuits are performed using Advanced Design System software (ADS).