Implementation of switched-current FIR filter using distributed arithmetic technique: exploitation of digital concept in analogue domain

Abstract

Recently, a distributed arithmetic (DA) technique has been employed in digital implementation of finite impulse response (FIR) filters, since it can significantly reduce hardware resources at the cost of higher clock frequency. In this paper, we show that the concept of DA can be efficiently exploited in an analogue domain. Specifically, a switched-current (SI) FIR filter is realized based upon the concept of DA. In addition, it is revealed that the DA SI FIR filter offers extended maximum achievable resolution normally dictated by transistor matching. The technique also helps reduce silicon area and power requirements. Two examples of FIR filter design according to WCDMA and cdma2000 specifications are presented to demonstrate the feasibility of the novel technique. Simulation results are shown to confirm the circuit functions.