General synthesis of complex analogue filters

摘要

General methods for the synthesis of complex band-pass and band-stop analogue filters are developed for implementation by active-RC, gm-C, switched-capacitor (SC) and switched-current (SI) techniques. These principles are extended to synthesis procedures for log-domain complex realisations. Circuits for filters and group delay equalisers are presented for both ladder and cascade-biquad realisations. These have been incorporated into the filter design software XFILTER. Various designs are compared, noise and sensitivity responses being shown.