A High-Performance 8-Tap FIR Filter Using Logarithmic Number System

This paper presents an approach for implementing a 8-tap high-performance digital FIR (Finite Impulse Response) filter using Logarithmic Number System(LNS). In the past, FIR filters were implemented by conventional number system; therefore, the speed was limited due to the multiply accumulate operations. We realize a fast FIR filter by utilizing the Logarithmic Number System, which allows simple implementation of multiplication using a fixed-point adder. And the serious demerit of Logarithmic Number System´s algorithm, conversions to and from the conventional number representations is effectively overcome by utilizing our pipeline architecture, so the delay and complexity of the filter is reduced. The critical path was reduced from a multiply-accumulate operation to an adder operation, and our FIR filter can operate at 1.3G Hz under the condition of 1.2 V power supply using SMIC 0.13um CMOS technology, and requires approximate 27 percent lesser area than the original FIR filter.