Requested Attenuation
*.ucf
Interpretation
less than 0 dB
Truncated to 0 dB
0 - 30 dB
Guaranteed accuracy according to the WaveShaper specification
30.1 - 40 dB
WaveShaper attempts to set attenuation to requested value. No guarantee of accuracy
greater than 40 dB
Signal set to ‘Block’
Note:
Excluding the WaveShaper 100A Tuneable Optical Filter which does not provide attenuation control.
Phase
The phase control range available in the WaveShaper is 0-2
π
. (Not available for 100A and 500A models.) The User Configured Filter
may specify a phase outside of this range; however this will be re-calculated by the WaveShaper software as input phase mod 2
π
.
Parameter
Units
*.ucf
Interpretation
Frequency
THz
Interpolated to fit defined filter bandwidth
Attenuation
dB
Value dependent
Phase
Rad
Modulo 2
π
Examples of
*.ucf files are provided with the software and should be studied to understand the structure of the file.
Note:
There is a degree of inter-linking between the amplitude and phase contouring and varying one will have some effect on the
other. In particular, applying large amounts of dispersion to a channel can have a significant impact on the channel amplitude
shape. For full details, see M.A.F. Roelens, J. Bolger, G. Baxter, S. Frisken, S. Poole and B.J. Eggleton, “Dispersion Trimming in a
Reconfigurable Wavelength Selective Switch”, in Journal of Lightwave Technology, vol. 26, p.73, 2008.
Using Microsoft Excel to generate
*.ucf files
When using Microsoft Excel to generate a
*.ucf file, the following points should be noted.
The file should be saved as Text (Tab delimited,
*.txt) file and subsequently renamed to have the suffix “.ucf”.
Before saving as a
*.txt file, the format of all columns should be set to ‘Number’ with at least three (3) decimal places. If
the number format is set to less than three decimal places, Excel may misinterpret the data during the translation to a
tab delimited file.
4.3
WaveShaper Presets (*.wsp)
Preset files provide a way to fully define the filter/switch profile of a WaveShaper across all Frequencies and Ports. As such it is a
very powerful tool to easily configure a WaveShaper to a required complex spectrum.
To ensure data integrity, the WaveShaper software parses the .wsp files to ensure the requested filter shape is calculated to
conform to the limits set by the WaveShaper capabilities. The following rules for preparing and interpreting
.wsp files therefore
apply.
File Structure
The format of a .wsp file is a tab delimited text file with four columns: Absolute Frequency (THz), Attenuation (dB), Phase (Rad) and
Port. The file can be generated using a spreadsheet program, such as Microsoft Excel (saving the document as a tab delimited text
file). The file extension must be “.wsp” for the file to appear in the File Open dialog box.
Number of Frequency Data Points
Unlike .ucf files, every GHz must be specified for the whole available spectrum in every .wsp file. The first and last points in the file
must be must be within the operating frequency range for the respective WaveShaper model. A partial definition that covers a
WaveShaper A Series User Manual
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