SWD signal processing based on wavelet domain correlation algorithm

Due to the low vibration energy of drill-bit and the high energy of rig noise along with some other reasons,conventional cross-correlation can not extract the information effectively.Put forward wavelet transform domain correlation algorithm,reference channel and receiving channel was done by wavelet transform respectively,and the delay information was detected by cross-correlation of time-frequency information,and then,the direct wave or the reflected wave information was extracted.Numerical simulation and field experiments show that,compared with the traditional cross-correlation technique,the wavelet transform correlation algorithm has a better ability to suppress the noise,and detect the wave delay of SWD information accurately and clearly.