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Linear plus cork-screw

An improvement to the linear interpolation technique can be made by multiplying the linear interpolator by $\exp {(-i \pi \delta n)}$, which, in the time-space domain, corresponds to moving the center of the sinc2 function to T/2, so that the original values between T/2 and T are stronger than the wraparound between -T/2 and . The linear plus cork-screw operator is

\begin{displaymath}
C_{n+ \delta n}=\exp {(-i \pi \delta n)}[(1- \delta n)C_n +(\delta n) C_{n+1}]\end{displaymath} (4)

In Figure 3, we show the implement of this operator. This result is better than Figure 1 and Figure 2, i.e. the artifacts are still obvious for the top and bottom impulse responses, because the amplitude of the sinc2 function varies with time and space. Only the original value at the center of the section is not affected by the artifact because for $n*T+T \over 2$, the wraparound is multiplied by a zero value of the sinc2 function.


previous up next print clean
Next: Harlan's 10-point interpolation Up: DESCRIPTION OF THE FIVE Previous: Linear interpolation
Stanford Exploration Project
11/16/1997