Attempts of singular value decomposition in the separation of the simultaneous vibroseis sweep data
Ni Yudong, Yunshan Lei, Wang Jingfu, Yangsheng Li, Lv Zhejian, Ma Weining · 2012
Using different phase encoding schemes, a composite record comprising of different single-shot data can be acquired at different locations through simultaneous sweep with multiple vibrators. There are many ways to decompose this composite record into independent single-shot records. This paper analyzes the cause that leads to ill-conditioned matrix during data separation, introduces the basic principles of the singular value decomposition(SVD) method and gives a real case of data separation using the method. Other methods such as Gauss-Jordan elimination method can also achieve data separation; however comparison of the data separation results between the singular value decomposition method and Gauss-Jordan elimination method in this paper shows that compared to the later, the S/N ratio of the single-shot record obtained with the former is much higher. A 90-degree phase shift of the original data is performed using Hilbert transform before data separation operation.