An Implementation of Parallel 1-D Real FFT on Intel Xeon Phi Processors

In this paper, we propose an implementation of a parallel one-dimensional real fast Fourier transform (FFT) on Intel Xeon Phi processors. The proposed implementation of the parallel one-dimensional real FFT is based on the conjugate symmetry property for the discrete Fourier transform (DFT) and the six-step FFT algorithm. We vectorized FFT kernels using the Intel Advanced Vector Extensions 512 (AVX-512) instructions, and parallelized the six-step FFT by using OpenMP. Performance results of one-dimensional FFTs on Intel Xeon Phi processors are reported. We successfully achieved a performance of over 91 GFlops on an Intel Xeon Phi 7250 (1.4 GHz, 68 cores) for a 2(29)-point real FFT.