Pipelined Scaling of Signed Residue Numbers with the Mixed-radix Conversion in the Programmable Gate Array

In this work a scaling technique of signed residue numbers is proposed. The method is based on conversion to the Mixed-Radix System(MRS) adapted for the FPGA implementation. The scaling factor is assumed to be a moduli product from the Residue Number System (RNS) base. Scaling is performed by scaling of terms of the mixed-radix expansion, generation of residue representations of scaled terms, binary addition of these representations and generation of residues for all moduli. The sign is detected on the basis of the value of the most significant coefficient of the MRS representation. For negative numbers their residues are adequately corrected. The basic blocks of the scaler are realized in the form of the modified two-operand modulo adders with included additional multiply and modulo reduction operations. The pipelined realization of the scaler in the Xilinx environment is shown and analyzed with respect to hardware amount and maximum pipelining frequency. The design is based on the LUTs(26x 1) that simulate small RAMs serving as the main component for the look-up realization.