A novel approach, based on a radix-4 Booth encoding, is presented for constant coefficient multipliers. The major advantage of this approach is that it reduces the amount of reconfiguration time needed to switch between multipliers when compared to the Xilinx constant coefficient multiplier (KCM) core. The approach utilises an existing radix-4 Booth encoding system and gives reductions in the reconfiguration data required to switch multiplier coefficient by an average of 59% and a worst case of 34%. The proposed structure is 4 CLBs smaller and 4% faster than the KCM approach. The approach exploits the MUXes in the Virtex routing network to perform the reconfiguration of the radix-4 Booth encoded multiplier
Tim Courtney, Richard H. Turner, Roger Woods