Abstract: To overcome the shortcomings of high time complexity and long computing time about cross-correlation extrapolation algorithm, an improved GPU-based fast parallel algorithm is presented, which is applied to extrapolate the Cloud-to-Ground flash development trend. First of all, we analyze the serial algorithm flow, and then design the parallel algorithm flow, optimize the algorithm by way of improving the data transfer between device memory and main memory, and optimize the memory access patterns. These optimization measures are based on OpenCL technology and aimed at the hardware architecture of AMD series GPU. Finally, we compare the Cloud-to-Ground flash monitoring data against the extrapolation results computed by this algorithm, and analyze the efficiency of the serial and the parallel algorithms under different precisions. The experimental result indicates that, the algorithm takes advantage of the powerful GPU parallel computing capability, and the calculation speed increases by nearly 17 times.

Key words: GPU, parallel computing, cross-correlation extrapolation, lightning extrapolation, OpenCL