Virtual instrument applied in seismic time delay signal process

It is very important to do some preliminary analysis and processing of the time delay signal before the time delay estimation for the target orientation of the multi-sensor network. In this paper, a virtual instrument time delay analysis system is designed, which contains: a virtual oscilloscope, a virtual spectrum analyzer, a virtual filter and a virtual time delay analyzer. By the use of this analysis system, the spectrum of the seismic target signal collected in the field is analyzed. Analysis shows the main frequency of the target signal: 13Hz, 85Hz, 170Hz, 125Hz. Distinctness of the time delay peak is proposed to describe the validation of the cross-correlation result. Based on the three main frequency components, signals were filtered by five filters and analyzed separately. Results were shown in figures of time delay vs. time, distinctness vs. time. Each curve in a figure corresponds to a certain number of points of cross correlation. According to the results, the frequency component from 8Hz to 30Hz is much more suitable for practical use. The regular pattern of the time delay curve is consistent with the target motion. Application reveals that the system is helpful in the research of time delay estimation.