Frequency Response graph

The Frequency Response graph is intended to be used with Sv variables that have been recorded in parallel on differing frequencies. It is an XY plot of normalized NASC (Y) against frequency (X). The Frequency Response graph can be linked.

NASC is normalized against a reference value (the reference value is the NASC at one of the displayed frequencies).

To display the Frequency Response graph from an echogram:

On the View menu, point to Graph, then click Frequency Response
The Frequency Response graph properties dialog box will allow you to configure the graph, especially to select the displayed variables and the reference variable
Make a selection, or click on a region (on an echogram you selected in step 2)
Use Graph menu > Linking to select the linking to the graph.

It is only possible to view one Frequency Response graph per EV file.

Reference

Korneliussen, R. and Ona, E (2003). Synthetic echograms generated from relative frequency response. ICES Journal of Marine Science, 60:636-640.

Frequency Response graph

Reference

See also