DESCRIPTION OF THE SUBTRACTION ALGORITHMS

Let us consider a simple model of seismic traces recorded by an N-channel seismic array:

 

X_i(f)=U_i(f)+S_i(f), (1)

where X_i(f) is the Fourier component of the trace i for frequency f, U_i(f) is signal from the source we want to locate, and S_i(f) is the unwanted (interfering) signal. An important assumption is that signals from different sources are uncorrelated with one another, but signals from the same source at different traces are well-correlated.