Separation of Blended Impulsive Sources using an Iterative Approach

Traditional data acquisition practice dictates the existence of sufficient time intervals between the firing of sequential impulsive sources in the field. However, much attention has been drawn recently to the possibility of shooting in an overlapping fashion. Numerous publications have addressed the issue from different scopes (de-noising, compressing, blind signal separation etc.) while others have defined the theoretical background. The term 'blending' has been introduced to describe this new trend in acquisition designs, the time-overlapping data acquisition. In turn, the term 'deblending' refers to an algorithm that recovers the data as if they were shot in the traditional way. Such an algorithm is presented in this paper, specially designed for the case of impulsive sources that fire with small time-delays. This algorithm is based on iterative interference estimation and subtraction. The key to signal extraction from blended data is the incoherency of the interference (as opposed to the coherency of the signal) accomplished by resorting the data into a different than the common source domain. The method is applied on a real marine dataset, where the blending process has been simulated numerically.