LDV，laser doppler vibration

The sampling rate of laser Doppler vibration measurement data is 250MHZ, and the number of sampling points is 20M.A total of 12 frequency bands of 0.5kHZ, 1kHZ, 2kHZ, 3kHZ, 4kHZ, 5kHZ, 6kHZ, 7kHZ, 8kHZ, 9kHZ, 10kHZ, 11kHZ were collected, which ensured that there were at least 5 vibration samples in each frequency band, and 20 samples were collected in some frequency bands.