|1||Open a new project with File > New > Single Fiber.|
|2||Choose Calculation > Inverse Scattering Solver to get the Inverse Problem Solver dialog box.|
|3||Set the From and To wavelength fields to 1.5498 and 1.5502.|
|4||Set the grating length at 20 cm in the Length field.|
|5||Click on the Ref/Trans Define button to define the reflection spectrum.|
|6||Set the bandwidth to 0.4 nm and the reflectivity to 0.9 within this band.|
|8||Select the Disp radio button and click the adjacent Define button to define the dispersion spectrum.|
|9||In this screen, set the dispersion to -1800 ps/nm for all wavelengths, as seen above.|
|11||Click the Causality button to see the impulse response of the specified spectrum.|
|1||Click Start in the Inverse Problem Solver dialog box to start the layer peeling algorithm..|
|2||Select the Delay tab.|
|3||Select the red and light blue curves to show the transmitted and reflected delays. The dark blue curve shows the target delay.|
|4||Click in the graph window and go to Tools > Group Delay|
- The window displays the reconstructed group delay with a second order fitting.
The dispersion is reported in the Results frame as -1773.79 ps/nm, in close
agreement with the desired response.