Step 1

1 Open a new project with File > New > Single Fiber.
2 Choose Calculation > Inverse Scattering Solver to get the Inverse Problem Solver dialog box.

Optical Grating - 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.

Optical Grating - User Defined Function

6 Set the bandwidth to 0.4 nm and the reflectivity to 0.9 within this band.
7 Click OK.
8 Select the Disp radio button and click the adjacent Define button to define the dispersion spectrum.

Optical Grating - User Defined Function

9 In this screen, set the dispersion to -1800 ps/nm for all wavelengths, as seen above.
10 Click OK.
11 Click the Causality button to see the impulse response of the specified spectrum.

Optical Grating - View 2d graph

12 Click Close.

Step 2

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

Optical Grating - 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.