Signal Processing Toolbox |
Scale the roots of a polynomial
Syntax
Description
b
scales the roots of a polynomial in the z-plane, where =
polyscale(a,alpha)
a
is a vector containing the polynomial coefficients and alpha
is the scaling factor.
If alpha
is a real value in the range [0 1]
, then the roots of a
are radially scaled toward the origin in the z-plane. Complex values for alpha
allow arbitrary changes to the root locations.
Remark
By reducing the radius of the roots in an autoregressive polynomial, the bandwidth of the spectral peaks in the frequency response is expanded (flattened). This operation is often referred to as bandwidth expansion.
See Also
poly2rc | polystab |
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