The paper presents a unified approach to the design of analoguenfinite impulse response (FIR) filters. As an analogue realisation thenmultiphase switched-capacitor technique was chosen owing to its highnprecision and high packing density in CMOS technology. The proposednmethod allows different structures of the filters containing differentnnumber of amplifiers to be controlled by different clock signals,nproviding the best solution taking into account the maximum frequencynrange and the cost of the chip. Four prototypes of the filters werendesigned as one integrated circuit using 2 Μm double-poly CMOSntechnology. Measurements made on the test chip confirm the computernsimulations. Implementation of interpolation units for analogue FIRnfilters derived from transversal direct diagram of digital FIR filtersnis discussed. The linear interpolator provides an improvement to thenfrequency characteristic of the prototype analogue FIR filter. Computernsimulation of the resulting filter has been performed
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