FFT analysis in Simulink - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to add an FFT block to the Simulink model.

Simulink

add_block('dspsigops/FFT', '[1]');

Drag options to blanks, or click blank then click option'

AmyModel/FFT

BmyModel/Sine Wave

CmyModel/Scope

DmyModel/Gain

Attempts:

3 left

💡 Hint

Common Mistakes

Using a block path that does not exist in the library.

Using a destination path that conflicts with existing blocks.

The FFT block should be added with a unique path like 'myModel/FFT' to the Simulink model.

2fill in blank

medium

Complete the code to set the FFT block's input port to the signal named 'inputSignal'.

Simulink

add_line('myModel/[1]', 'myModel/FFT/1');

Drag options to blanks, or click blank then click option'

AoutputSignal

BcontrolSignal

CinputSignal

DnoiseSignal

Attempts:

3 left

💡 Hint

Common Mistakes

Setting the input to a signal that does not exist.

Using the output signal name instead of the input.

The FFT block input should be set to the signal named 'inputSignal' to analyze that signal.

3fill in blank

hard

Fix the error in the code to correctly run the FFT analysis simulation.

Simulink

simOut = sim('[1]');

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AmyModel.txt

BmyModel

CmyModel.mdl

DmyModel.slx

Attempts:

3 left

💡 Hint

Common Mistakes

Including file extensions in the model name string.

Using a file type that Simulink does not recognize.

The 'sim' function requires the model name without file extension to run the simulation.

4fill in blank

hard

Fill both blanks to extract the FFT magnitude and frequency from the simulation output.

Simulink

fftData = simOut.[1];
frequencies = simOut.[2];

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AfftMagnitude

BfftFrequency

CfftMag

Dfreq

Attempts:

3 left

💡 Hint

Common Mistakes

Using incorrect or non-existent variable names.

Mixing magnitude and frequency variable names.

The simulation output contains 'fftMag' for magnitude and 'freq' for frequency data.

5fill in blank

hard

Fill all three blanks to plot the FFT magnitude versus frequency with labels.

Simulink

plot([1], [2]);
xlabel('[3]');

Drag options to blanks, or click blank then click option'

Afrequencies

BfftData

CFrequency (Hz)

DfftMagnitude

Attempts:

3 left

💡 Hint

Common Mistakes

Swapping x and y data in the plot function.

Forgetting to label the x-axis.

Plot frequency on x-axis and FFT magnitude on y-axis, labeling x-axis as 'Frequency (Hz)'.