Rohde & Schwarz R&S UPP, Руководство пользователя

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Instrument Functions
R&S
®
UPP
476 User Manual 1411.1055.32 ─ 10
The coefficient file
*.COE
is only valid for the sampling rate determined during the
design stage, i.e. the frequency response of the filter is standardized to this sampling
rate. If a different sampling rate is set in the R&S UPP, the frequency response
changes accordingly.
5.40.5.3 Poles and zeros of the transfer function
The filter is defined by specifying the poles and zeros on the Z level. Four pairs of
poles and zeros are permitted. Unused poles and zeros must be placed at the origin of
the Z level.
The transfer function S(z) is then derived as follows:
 
  
   



 
 
 
3
0
3
0
*
*
i
i
Zpi Z Zpi Z
Zoi Z Zoi Z
gain z S
Equation 5-5: where: z0 = zeros, zp = poles, z* = conjugate complex number.
File format *.zpz
Example:
See
RS_EXAM.ZPZ
in
D:\UPV\USER
The
*.ZPZ
poles/zeros file is only valid for the sampling rate determined during the
design stage, i.e. the frequency response of the filter is standardized to this sampling
rate. If a different sampling rate is set in the R&S
UPP, the frequency response
changes accordingly.
File format *.npz
Example:
See the
RS_EXAM.NPZ
file in the
D:\UPV\USER
directory
Poles and zeros in the
*.NPZ
are standardized to the sampling frequency specified
there. If a different sampling rate is set in the R&S UPP poles and zeros are conver-
ted to this rate so that the frequency response of the filter remains unchanged. A refer-
ence point for the frequency response, defined in terms of a reference frequency and
the reference gain at this frequency, must be specified in the file.
File format *.xpz
This file format is an extension of the "npz" format. The file can contain multiple param-
eter sets for the pole and zero locations. For each parameter set, the associated sam-
pling frequency must be specified, along with the sampling frequency range within
which the pole and zero locations can be transformed such that the frequency
User-Definable Filters