A fast radix-4 division algorithm and its architecture

In this paper we present a fast radix-4 division algorithm for floating point numbers. This method is based on Svoboda´s division algorithm and the radix-4 redundant number system. The algorithm involves a simple recurrence with carry-free addition and employs prescaling of the operands. In the proposed divider implementation, each radix-4 digit (belonging to set {-3,...,+3}) of the quotient and partial remainder is encoded using two radix-2 digits (belonging to the set {-1,0,+1}) and this leads to hardware simplicity. The quotient digits are determined by observing three most-significant radix-2 digits of the partial remainder and independent of the divisor. The architecture presented for the proposed algorithm is faster than previously proposed radix-4 dividers, which require at least four digits of the partial remainder to be observed to determine quotient digits