Signal Modulation

This repository contains solution to assignment for Principal of Communications Systems course at VJTI, Mumbai

Generate sample data

• To generate a sample signal as the input signal, run the following command:

  python3 generate_signal.py

  Output of the file, enter the number of data points to generate, we take 1000 data points for this example

  Press 1 for sin wave
  Press 2 for cosine wave
  Press 3 for using custom audio file (wav format)
  Enter option: 2
  Enter number of elements: 1000

• To use custom audio file as input

  Press 1 for sin wave
  Press 2 for cosine wave
  Press 3 for using custom audio file (wav format)
  Enter option: 3
  Enter audio file name: custom.wav

  This will generate a file called data.txt with float values on each line.

Amplitude Modulation

Write a program in MATLAB/Python/Scilab (any) to generate an AM wave for a given modulation index and modulating signal. The modulation index, carrier frequency and modulating signal must be taken as input from user.

Plot one signal below the other in a single figure as subparts, for convenient visualization.

To generate AM output signal, run the following command:

python3 amplitude_modulation.py

Sin signal as input

Output of python file

Enter File Name: data.txt
Enter value of modulation index (0-1): 0.9
Enter value of carrier frequency: 10000

Cosine signal as input

Output of python file

Enter File Name: data.txt
Enter value of modulation index (0-1): 0.4
Enter value of carrier frequency: 100000

Custom Audio file as input

Output of python file

Enter File Name: data.txt
Enter value of modulation index (0-1): 0.6
Enter value of carrier frequency: 1000

Frequency Modulation

Write a program in MATLAB/Python/Scilab (any) to generate an FM wave for a given deviation ratio and modulating signal. The deviation ratio, carrier frequency and modulating signal must be taken as input from user.

Plot one signal below the other in a single figure as subparts, for convenient visualization.

To generate FM output signal, run the following command:

python3 frequency_modulation.py

Sin signal as input

Output of the python file

Enter File Name: data.txt
Enter value of deviation ratio: 10
Enter value of carrier frequency: 1000

Cosine signal as input

Output of the python file

Enter File Name: data.txt
Enter value of deviation ratio: 10
Enter value of carrier frequency: 1000000

Custom audio file as input

Output of the python file

Enter File Name: data.txt
Enter value of deviation ratio: 10
Enter value of carrier frequency: 10000