How to Use the Modulation/Demodulation Simulator

1. Open MATLAB, Select File, Select Open, Browse for Mod_Demod_Sim.m.

2. Select Debug, Select Run                                                                                                       

     NOTE: The graphical user interface will display, if not, see troubleshooting link.

                NOTE:  For the following steps reference Figure 1: GUI label.

3. Choose a signal that you would like to analyze from the Input Signal drop-down menu. The signal will automatically display in the graph labeled, Original Signal.

4. The chosen input signal has a default carrier frequency, which will be displayed in the carrier frequency field.  Enter an alternate carrier frequency, for further analysis. 

5. Choose a Mod/Demod Scheme: AM, FM, SSB.

6. Press Modulated/Plot button to view graph in Modulated Signal.

7. Press Demodulate/Plot button to view graph in Demodulated Signal.

8. Listen to the original, modulated, or demodulated signal by pressing the Play button located above each graph.                        

     NOTE: Speakers or headphones must be activated, to hear the playback.

9. You may change the signal, modulation scheme, or the carrier frequency at any time.

     NOTE: To see the new plots or hear signal you will have to push the Modulate/Plot and      Demodulate/Plot buttons.

          10. Press the Close button to exit the program.

                Optional Channel Characteristics:  1. Check Add Noise to simulate channel noise.

                                                                                2. Check Add Filter to simulate receiver filter.

 

Figure 1: Mod/Demod GUI