NGMV Control Toolbox

Z-domain polynomial spectral factorization.

Syntax

• A = SPFZ(B)

  A = SPFZ(B,'method')

  A = SPFZ(B,'method',TOL)

  [A,ERR] = SPFZ(...)

Description

This routine solves the polynomial spectral factorization problem in Z-domain:

B is a right half of a mirror-image polynomial BB positive on the unit circle and A is a stable polynomial.

The string 'method' specifies one of the following algorithms:

'def'              -- based on the factorization of B and selection of stable factors.

'kucera'        -- Vostry / Kucera’s method. This is the default method.

'gauss2'        -- numerical method based on solving a linear polynomial equation (2^nd order)

'gauss3'        -- numerical method based on solving a linear polynomial equation (3^rd order)

The tolerance TOL can be specified as an additional argument. Its default value is TOL = 10*eps.

The error of the solution can be returned in ERR.

.See Also

spfc

Reference

Kucera V, Discrete Linear Control,1979

spfc

thru