Integrated circuits with specialized processing blocks for performing fast Fourier floating point transforms and complex multiplication

摘要

Integrated circuits with specialized processing blocks are provided. A specialized processing block may include a real adder and a real multiplier. The multiplication stage can simultaneously feed its output to the adder stage and directly into a neighboring specialized processing block. The adder can also generate sum and difference outputs in parallel. A group of four such specialized processing blocks may be connected in a chain to implement a Radix-2 Fast Fourier Transform Butterfly. Several Radix-2 Butterflies can be stacked to make the butterflys of a radix of even greater potency. If desired, the specialized processing block may also be used to implement a complex multiply operation. Three or four specialized processing blocks may be chained together and together with one or more adders outside the specialized processing blocks, real and imaginary parts of a complex product may be generated.