How to plot AM Single-sideband modulation with carrier (AM-SSB-WC) and AM Single-sideband modulation suppress carrier (AM-SSB-SC) in MATLAB?

I have found the

fs = 200e3;

y = ssbmod(x,50e3,fs);

x is the audio wavefile.

But i dont know its its wit carrier( WC ) or Suppress carrier (SC).

Answer 1

[Hari]

Hi,

I understand that you want to plot both AM Single-Sideband with Carrier (AM-SSB-WC) and AM Single-Sideband Suppressed Carrier (AM-SSB-SC) modulations in MATLAB, and you are unsure about the modulation type used by the "ssbmod" function.

I assume you have already defined your audio signal x and its sampling frequency fs.

In order to plot both AM-SSB-WC and AM-SSB-SC, you can follow the below steps:

Modulate the Signal using AM-SSB-SC:

Use the "ssbmod" function for AM-SSB-SC modulation. This function inherently performs SSB-SC modulation.

fc = 50e3; % Carrier frequency
ssbSC = ssbmod(x, fc, fs);

Generate AM-SSB-WC Signal:

To include the carrier, add a scaled version of the carrier signal to the SSB-SC modulated signal.

t = (0:length(x)-1)/fs; % Time vector
carrier = cos(2*pi*fc*t);
ssbWC = ssbSC + 0.5 * carrier; % Adjust the scaling factor as needed

Plot the AM-SSB-SC Signal:

Visualize the SSB-SC signal in the time domain.

figure;
plot(t, ssbSC);
xlabel('Time (s)');
ylabel('Amplitude');
title('AM-SSB-SC Modulated Signal');

Plot the AM-SSB-WC Signal:

Similarly, plot the SSB-WC signal to compare the modulation types.

figure;
plot(t, ssbWC);
xlabel('Time (s)');
ylabel('Amplitude');
title('AM-SSB-WC Modulated Signal');

Refer to the documentation of "ssbmod" function to know more about its usage: https://www.mathworks.com/help/comm/ref/ssbmod.html

Hope this helps!