Impulse Response

) to a 1D plot group to create an impulse response plot. After defining the characteristics of the impulse response, click (

) to create the impulse response plot. If you want to add color to the impulse response, add a subnode. The impulse response plot reconstructs the impulse response based on a Ray Acoustics simulation.

	For details on setting up a Ray Acoustics model and postprocess the impulse response, see Impulse Response and Receiver in the Acoustics Module User’s Guide.

	Go to Common Results Node Settings for links to information about these sections: Title and Coloring and Style.

From the list, choose an applicable dataset or . The default option, , uses the dataset from the parent plot group node. Only the Receiver 2D and Receiver 3D datasets are valid for this specialized plot.

From the list, choose an interpretation of the frequency: (the default), , or . This selections should coincide with the frequency interpretation used in boundary conditions and sources in the underlying Ray Acoustics simulation. The frequency content and resolution of the impulse response are based on this selection.

Set up the variables that are necessary for reconstructing the impulse response. In practice these variables are used to define and add the contribution of each ray that intersects the receiver dataset to the impulse response.

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Define the density (SI unit: kg/m3) in the field. The default is rac.rho.

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Define the speed of sound (SI unit: m/s) in the field. The default is rac.c.

For all text fields, click the (

) button to select a predefined quantity and replace the entire contents of the field.

From the list, choose a transformation of the data on the x-axis: (the default) for no transformation, or . For a frequency spectrum, the following properties are available:

Select the check box and enter the number in the associated text field.

For a frequency range, select the check box and defined the range using the and fields (SI unit: Hz).

Select the check box to transform the frequency spectrum so that it has the same scale as the original data.

The following settings are available to control the Kaiser-Bessel window functions that are used to reconstruct the frequency content of the impulse response. Each ray contributes with an amplitude, arrival time, and frequency content to the time-domain signal.

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Define a sampling frequency (SI unit: Hz) in the field. The default is 44100.

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Define a passband slope factor in the field. The default is 1.03.

Select to (selected per default). This options removes the unphysical parts of the impulse response signal that appear before the arrival time of the first ray. This part is generated due to the nature of the window functions used for the signal reconstruction.

The check box is selected by default to display the plotted expressions to the right of the plot. In plots where each line represents a certain time value, eigenvalue, or parameter value, these values are also displayed.

When is selected from the list (the default), select or clear the , , and check boxes to control what to include in the automatic legends (by default it includes the description only). You can also add a prefix or a suffix to the automatic legend text in the and fields. If is selected from the list, enter your own legend text into the table.