Application of Phase Information in Processing Acoustic Emission Signal

Acoustic emission signal needs high sample rate with large numbers of data and its energy is weak. According to these, the power spectral density analysis method basedon phase enhancement technique was studied. The signaltonoise ratio was increased with second FFT on the signal after highspeed sampling process without losing useful information. Simulation and practice diagnostic application verified the effectiveness of the method. Applied to detect the crack growth on the crank shoulder of septumpump in running condition, the weak acoustic emission signal due to crack growth was detected easily.