Fourier-domain dedispersion

We present and implement the concept of Fourier-domain dedispersion (FDD) algorithm, a brute-force incoherent algorithm. This algorithm corrects frequency-dependent dispersion delays in arrival time radio emission from sources such as pulsars fast bursts. Where traditional time-domain algorithms correct using shifts, FDD performs these shifts by applying phase rotations to Fourier-transformed time-series data. Incoherent many trial measures (DMs) is compute, memory-bandwidth I/O intensive have been implemented on Graphics Processing Units (GPUs) achieve high computational performance. However, low arithmetic intensity are therefore often limited. The avoids this limitation compute limited, providing path exploit potential current upcoming generations GPUs. an extension DEDISP software. compare performance energy-to-completion implementation NVIDIA Titan RTX GPU against standard well optimized version DEDISP. already provides factor 1.5 2 speedup at only 66% energy utilization compared original find that outperforms another 20% 5% when large number DMs (>=512) required. additional improvements for FFT-based periodicity surveys pulsars, FFT back domain can be omitted. expect gain will further improve future.