National Instruments 373873C-01 Running Multidimensional Sweeps

Chapter 6 Performing Sweep Measurements

3. Click the Run Once button again to execute the sweep.

The frequency response of the Filter step plots on the new graph while

the project runs. The graph displays the transfer function of the filter,

or the amplitude output expressed in decibels versus the frequency.

4. Double-click the Filter step to display the filter specifications in the

Step Setup dialog box.

The frequency response of the filter in the Filter Magnitude

Response graph matches the graph in the Data View.

5. Select File»Save Project As and save the project as

My Sweep.seproj in the SignalExpress\Examples\Tutorial

directory.

You can use the Sweep step to sweep multiple parameters simultaneously

by adding additional parameters on the Sweep Configuration tab of the

Sweep Step Setup dialog box. Sweeping two or more parameters

simultaneously is called a parallel sweep. For example, if you want to vary

the amplitude of a stimulus signal, you can run a parallel sweep. You can

use a parallel sweep to maximize the precision of the acquisition by varying

the input range of a digitizer or MIO device as you vary the signal level. As

the signal level increases, you can increase the input range of the

measurement device to ensure you use the entire resolution for the

measurement.

Running Multidimensional Sweeps

Use multidimensional, or nested, sweeps to iterate through one range while

you vary another range. For example, if you want to sweep through

frequencies of a stimulus signal at different amplitudes, run a nested sweep.

You can set the amplitude to level 1 and sweep through frequencies, and

then set the amplitude to level 2 and sweep through frequencies, and so on.

You can build a nested sweep by right-clicking a Sweep step in a project

and selecting Add Dimension from the shortcut menu to add another

sweep loop.

Complete the following steps to run a sample nested sweep project.

1. Select File»Open Project, navigate to the SignalExpress\

Examples\Tutorial directory, and double-click Nested

Sweep.seproj.

2. Click the Run button, shown at left, to run the project.

Each iteration of the inner sweep loop sweeps the frequency of the

stimulus signal. The outer sweep loop varies the low and high cutoff