ReFACE: Efficient Design Methodology for Acceleration of Digital Filter Implementations

Because of the impressive performance and success of artificial intelligence (AI)-based applications, filters as a primary part of digital signal processing systems are widely used, especially finite impulse response (FIR) filtering. Although they offer several advantages, such as stability, they are computationally intensive. Hence, in this paper, we propose a systematic methodology to efficiently implement computing in-memory (CIM) accelerators for FIR filters using various CMOS and post-CMOS technologies, referred to as ReFACE. ReFACE leverages a residue number system (RNS) to speed up the essential operations of digital filters, instead of traditional arithmetic implementation that suffers from the inevitable lengthy carry propagation chain. Moreover, the CIM architecture eliminates the off-chip data transfer by leveraging the maximum internal bandwidth of memory chips to realize a local and parallel computation on small residues independently. Taking advantage of both RNS and CIM results in significant power and latency reduction. As a proof-of-concept, ReFACE is leveraged to implement a 4-tap RNS FIR. The simulation results verified its superior performance with up to 85× and 12× improvement in energy consumption and execution time, respectively, compared with an ASIC accelerator.