Design of Delay Efficient Distributed Arithmetic Based Split Radix FFT

Abstract — In this paper a Split Radix FFT without the use of multiplier is designed. All the complex multiplications are done by using Distributed Arithmetic (DA) technique. For faster calculation parallel prefix adder is used. Basically high radix algorithms are developed for efficient calculation of FFT. These algorithms reduces overall arithmetic operations in FFT, but increases the number of operations and complexity of each butterfly. In Split Radix FFT, mixed-radix approach helps to achieve low number of multiplications and additions. DA is basically a bitserial computational operation that forms an inner (dot) product of a pair of vectors in a single direct step. The advantage of DA is its efficiency of mechanization. A method is incorporated to overcome the overflow problem introduced by DA method