Figure 6.4: Singular values of the measurement matrices decay very fast.
pins. For each circuit, we have measured the path delays for a number of paths
in the testable basis set, reported in the fourth column. The fifth column shows
the ratio of the ΛΓ∕2-th singular value of the measurement matrix to the 1-st one.
The M/3 and the Λ4∕2-dimensional subspaces—the sizes of which are reported in
the sixth column—were estimated for the ^-regularization, the ^-minimization,
and the TUSC methods were evaluated (M is the number of measurements). The
remaining columns demonstrate the results for 3%, 6%, and 9% measurement
noise. On average, the ^!-regularization and the TUSC perform more than two
times better in estimating the variations.
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