Accelerate the Time-Reversal Computing of Lightning Location Using GPU and Phase-Difference Filter

Time-reversal (TR) technique has been proved to be an effective method to locate the lightning sources, which could get much more accurate results and is capable of finding the weak radiation sources. However, the huge amount of calculation makes it not meet the fast localization requirement of the lightning map array. To accelerate the localization speed of TR, this article proposes to use graphics processing unit (GPU) parallel computing and shared memory to calculate the radiation source directions. Then, the phase difference is combined with TR to filter out the less relevant direction points thus to further speed up the computation. Finally, as for the real lightning data received by the antennas, not every sliding window contains the radiation signals during the TR calculation, we use the signal-interference energy ratio to judge whether a sliding window has the radiation signal, thus, we only need to calculate the windows of which the ratios are above the threshold. Experiments show that, in simulation, by using the first two skills, the computing speed is greatly improved by more than 1700 times than a single CPU serial computing; in 500 ms real lightning data localization, our method is 263 times faster than the original CPU methods, meanwhile, the location result is as good as the latter.