T. P. Traitement du Signal Maîtrise E.E.A. - LASC

6 SPTool: A Signal Processing GUI Suite
L
∏
Hz () = H k () z =
k = 1
L
b 0k + b 1k z – 1 +
∏
b z–
2
--------------------------------------------------------- 2k
1 + a 1k z – 1 + a z–
2
2k k = 1
The SOS Matrix field specifies a variable name or a value for the L-by-6 SOS
matrix
b 01 b 11 b 21 1 a 11 a 21
sos =
b 02 b 12 b 22 1 a 12 a 22
M M M M M M
b 0L b 1L b 2L 1 a 1L a 2L
whose rows contain the numerator and denominator coefficients b ik and a ik of
the second-order sections of H(z).
Note If you import a filter that was not created in SPTool, you can only edit
that filter using the Pole/Zero Editor.
Importing Spectra
When you import a power spectral density (PSD), you specify:
• A variable name or a value for the PSD vector in the PSD field
• A variable name or a value for the frequency vector in the Freq. Vector field
The PSD values in the PSD vector correspond to the frequencies contained in
the Freq. Vector vector; the two vectors must have the same length.
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