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Application of Phase Result

We now extend the result in equation 14 to discrete time. This equation thus becomes:
$\displaystyle \left(\frac{K}{2\pi}\right)^2\frac{\Delta^2 Y^{\mathrm{Hann}}(k)}{\Delta k^2} \Big\vert _{k=0}
= \frac{-j}{2\alpha}(Y^{\mathrm{Hann}}(0)).$     (16)

where we note that second order differencing operation with respect to frequency bin $k$ must be normalized by twice multiplying by $\frac{K}{2\pi}$. This expression may be solved for alpha to obtain:
$\displaystyle \fbox{$\displaystyle \alpha \approx
\frac{-jY^{\mathrm{Hann}}(0)}...
...frac{\Delta^2
Y^{\mathrm{Hann}}(k)}{\Delta k^2} \Big\vert _{k=0}\right)^{-1}.$}$     (17)

This estimator in general yields excellent results for cases where

Aaron S. Master 2002-10-17