Modified High-Speed FIR Filter Using DA-RNS Architecture
This paper presents a new architecture for high-speed Finite Impulse Response (FIR) filter based on Distributed Arithmetic-Residue Number System (DA-RNS) approach. Input is represented in Binary Code (BC) while the output is depicted using Look-up Tables (LUTs) in the proposed method. It is beneficial to use LUTs as it avoids logic complexity due to 2k modulo factor. The Existing approach based on shifters uses Thermometer Code (TC) and One Hot Code (OHC) respectively for input and output representation. Although this technique avoids the complex 2k modulo operation, the number of input TC bits are increased proportionally to the modulo size which results in degradation of the performance when the actual implementation of the circuit is considered. In the proposed solution, the BC is used at the input for its shorter word-lengths and the complexity introduced due to modulo 2k terms is eliminated by modulo 2k LUTs. It is observed from the results of different filter experiments that the proposed method using the LUT based Modulo Adder outperforms other architectures.