User`s guide
Spectral Analysis Example
Testing the Add-
In
Before distribu
ting the add-in, test it with a sample problem.
Spectral analys
is is commonly used to find the frequency components of a
signal buried in
a noisy time domain signal. In this example you will create a
data represent
ation of a signal containing two distinct components and add
to it a random co
mponent. This data along with the o utput will be stored in
columns of an Ex
cel worksheet, and you will plot the time-domain signal
along with the p
ower s pec tral density.
Creating the Test Problem
Follow these s
teps to create the test problem:
1 Start a new session of Excel with a blank workbook.
2 FromthemainmenuclickTools > Add-Ins.
3 When the Add-I
ns dialog box appears, select Browse .
4 Browse to the <project-directory>\distrib directory, select
Fourier.xla,andclickOK.
The Spectral Analysis add-in appears in the available Add-Ins list and
is selected.
5 Click OK to load the add-in.
This add-in installs a menu item under the Excel Tools menu. You can display
the Spectral Analysis GUI by selecting Tools > Spectral Analysis. Before
invoking the add-in, create some data, in this case a signal with components
at 15 and 40 H z. Sample the signal for 10 seconds a t a sampling rate of 0.01 s.
Put the time points into column A and the signal points into column B.
Creating th
eData
Follow these steps to create the data:
1 Enter 0 for c
ell A1 in the current w orksheet.
2 Click cell A2 and type the for mula "= A1 + 0.01".
3-27