VLSI Implementation of FIR Filter Using Computational Sharing Multiplier Based on High Speed Carry Select Adder

Abstract

Recent advances in mobile computing and multimedia applications demand high-performance and low-power VLSI Digital Signal Processing (DSP) systems. One of the most widely used operations in DSP is Finite-Impulse Response (FIR) filtering. In the existing method FIR filter is designed using array multiplier, which is having higher delay and power dissipation. The proposed method presents a programmable digital Finite Impulse Response (FIR) filter for high-performance applications. The architecture is based on a computational sharing multiplier which specifically doing add and shift operation and also targets computation re-use in vector-scalar products. CSHM multiplier can be implemented by Carry Select Adder which is a high speed adder. A Carry-Select Adder (CSA) can be implemented by using single ripple carry adder and add-one circuits using the fast all-one finding circuit and low-delay multiplexers to reduce the area and accelerate the speed of CSA. An 8-tap programmable FIR filter was implemented in tanner EDA tool using CMOS 180nm technology based on the proposed CSHM technique. In which the number of transistor, power (mW) and clock cycle (ns) of the filter using array multiplier are 6000, 3.732 and 9 respectively. The FIR filter using CSHM in which the number of transistor, power (mW) and clock cycle (ns) are 23500, 2.627 and 4.5 respectively. By adopting the proposed method for the design of FIR filter, the delay is reduced to about 43.2% in comparison with the existing method. The CSHM scheme and circuit-level techniques helped to achieve high-performance FIR filtering operation.