How to do frequency scaling in Frequency spectrum?

disp('%=================================================%')

disp('%~~~~~~~~ `` Assalamualaikum `` ~~~~~~~~~%')

disp('% ```` Principle of Communication ( MATLAB ) ````%')

disp('')

disp('%`````````` *GROUP MEMBERS* ``````````%')

disp('%`` 1. ONG JIA EEK - A17MB0157 ``%')

disp('%`` 2. MAISARAAH YUZLAN - A17MB0078 ``%')

disp('%`` 3. NUR RAIHAN NAJAH BINTI TURIMAN - A17MB0137 ``%')

disp('')

disp('%=================================================%')

z=1

while z==1

A = menu('Please, select one! ','1.FULL AM','2.DSB-SC','3.SSB-SC','4.DSBSC & SSBSC SPECTRUM')

switch A

case 1

%>>>>>>>>>>>>>>>>>>>> 1.AM Modulation Simulation <<<<<<<<<<<<<<<<<<<<<<<<<<

clc;

close all;

%XXXXXXXXXXXXXXXXX modulating signal generation XXXXXXXXXXXXXXXXXXXXXXXXXX

disp('fc value must be larger than fm value.');

Em=input('Enter the value of amplitude modulation, Em ='); %amplitude of modulating signal

fm=input ('Enter the value of frequency modulation, fm ='); % Frequency of modulating signal

Tm=1/fm; % Time period of modulating signal

t=0:Tm/999:6*Tm; % Total time for modulated signal simulation (6 cycles will be displayed)

tm=0:Tm/999:6*Tm; % Total time for modulating signal simulation (6 cycles will be displayed)

ym=Em*cos(2*pi*fm*tm); % Equation of modulating signal

%XXXXXXXXXXXXXXXXXXXXX carrier signal generation XXXXXXXXXXXXXXXXXXXXXXXXXX

Ec=input('Enter the value of carrier signal amplitude, Ec =');% Amplitude of carrier signal

fc=input('Enter the value if carrier signal frequency, fc =');% Frequency of carrier signal

Tc=1/fc; % Time period of carrier signal

tc=0:Tc/999:6*Tc; % Total time for carrier signal simulation (6 cycles will be displayed)

yc=Ec*cos(2*pi*fc*tc);% Equation of carrier signal

%XXXXXXXXXXXXXXXXXXXXXXXXXXXXXX AM Modulation XXXXXXXXXXXXXXXXXXXXXXXXXXXXX

m=Em/Ec; % modulation index

y= Ec*(1+m*cos(2*pi*fm*t)).*cos(2*pi*fc*t); % Equation of Amplitude modulated signal

figure(1);

subplot(3,1,1);

plot(t,ym, 'g'), grid on;% Graphical representation of Modulating signal

title ( ' Modulating Signal ');

xlabel ( ' time(sec) ');

ylabel (' Amplitude(volt) ');

subplot(3,1,2);

plot(t,yc, 'r'), grid on;% Graphical representation of carrier signal

title ( ' Carrier Signal ');

xlabel ( ' time(sec) ');

ylabel (' Amplitude(volt) ');

subplot(3,1,3);

plot(t,y, 'm');% Graphical representation of AM signal

title ( ' Amplitude Modulated signal ');

xlabel ( ' time(sec) ');

ylabel (' Amplitude(volt) ');

grid on;

case 2

%>>>>>>>>>>>>>>>>>>>> 2.Double-Sideband Suppressed-Carrier Transmission (DSB-SC) <<<<<<<<<<<<<<<<<<<<<<<<<<

clc;

clear all;

Em = input ('Enter the message signal amplitude = ');

Ec = input ('Enter the carrier signal amplitude = ');

fm = input ('Enter the message frequency = ');

fc = input ('Enter the carrier frequency = ');

m = Em/Ec;

%T=input('enter the duration over which the signal is to be plotted= ')

%fs=input('enter the sampling frequency= ')

%t=0:T/fs:T;

% Representation of the Message Signal

t = 0:0.0001:0.05;

Message_Signal = Em*cos (2*pi*fm*t);

subplot (3,1,1);

plot (t,Message_Signal,'b');

xlabel ('Time');

ylabel ('Amplitude');

title ('Message Signal');

legend ('Message Signal');

% Representation of the Carrier Signal

Carrier_Signal = cos(2*pi*fc*t);

subplot (3,1,2);

plot (t,Carrier_Signal,'r');

xlabel ('Time');

ylabel ('Amplitude');

title ('Carrier Signal');

legend ('Carrier Signal');

% Representation of the DSBSC Signal

DSBSC_Signal=Ec*m.*cos (2*pi*fm*t).*cos (2*pi*fc*t)

subplot (3,1,3);

plot (t,DSBSC_Signal,'m');

xlabel ('Time');

ylabel ('Amplitude');

title ('Double Sideband Suppressed Carrier Wave');

legend ('DSB-SC Signal');

% Add title to the Overall Plot

ha = axes ('Position',[0 0 1 1],'Xlim',[0 1],'Ylim',[0 1],'Box','off','Visible','off','Units','normalized', 'clipping' , 'off');

text (0.5, 1,'\bf Analog Modulation Technique: Double Sideband Suppressed-Carrier Transmission (DSB-SC)','HorizontalAlignment','center','VerticalAlignment', 'top')

case 3

%>>>>>>>>>>>>>>>>>>>> 3.Single-Sideband Suppressed-Carrier Transmission (SSB-SC) <<<<<<<<<<<<<<<<<<<<<<<<<<

clc;

clear all;

close all;

fm=input('enter the message frequency fm = ')

fc=input('enter the carrier frequency fc = ')

T=input('enter the duration over which the signal is to be plotted = ')

fs=input('enter the sampling frequency = ')

t=0:T/fs:T;

%t = 0:0.0001:0.05;

%generation of Modulating and Carrier signals and their Hilbert Transforms

m=cos(2*pi*fm*t) %modulating signal

m1=cos(2*pi*fm*t-(pi/2)) %Hilbert signal

n=cos(2*pi*fc*t) %carrier signal

n1=cos(2*pi*fc*t-(pi/2)) %Hilbert signal

%%generation of Two AM-DSB-SC signals

M=m.*n;

M1=m1.*n1;

%%generation of AM-SSB-SC signal

ssb=M+M1; %modulated signal

subplot (3,1,1);

plot (t,m,'b');

xlabel ('Time');

ylabel ('Amplitude');

title ('Message Signal');

subplot (3,1,2);

plot (t,n,'r');

xlabel ('Time');

ylabel ('Amplitude');

title ('Carrier Signal');

subplot (3,1,3);

plot (t,ssb,'m');

xlabel ('Time');

ylabel ('Amplitude');

title ('Single Sideband Suppressed Carrier Wave');

ha = axes ('Position',[0 0 1 1],'Xlim',[0 1],'Ylim',[0 1],'Box','off','Visible','off','Units','normalized', 'clipping' , 'off');

text (0.5, 1,'\bf Analog Modulation Technique: Single Sideband Suppressed-Carrier Transmission (SSB-SC)','HorizontalAlignment','center','VerticalAlignment', 'top')

case 4

%>>>>>>>>>>>>>>>>>>>> 4.DSBSC AND SSBSC FREQUENCY SPECTRUM <<<<<<<<<<<<<<<<<<<<<<<<<<

clc;

close all;

%XXXXXXXXXXXXXXXXX modulating signal generation XXXXXXXXXXXXXXXXXXXXXXXXXX

disp('fc value must be larger than fm value.');

Em=input('Enter the value of amplitude modulation, Em ='); %amplitude of modulating signal

fm=input ('Enter the value of frequency modulation, fm ='); % Frequency of modulating signal

Tm=1/fm; % Time period of modulating signal

t=0:Tm/999:6*Tm; % Total time for modulated signal simulation (6 cycles will be displayed)

tm=0:Tm/999:6*Tm; % Total time for modulating signal simulation (6 cycles will be displayed)

ym=Em*cos(2*pi*fm*tm); % Equation of modulating signal

%XXXXXXXXXXXXXXXXXXXXX carrier signal generation XXXXXXXXXXXXXXXXXXXXXXXXXX

Ec=input('Enter the value of carrier signal amplitude, Ec =');% Amplitude of carrier signal

fc=input('Enter the value if carrier signal frequency, fc =');% Frequency of carrier signal

Tc=1/fc; % Time period of carrier signal

tc=0:Tc/999:6*Tc; % Total time for carrier signal simulation (6 cycles will be displayed)

yc=Ec*cos(2*pi*fc*tc);% Equation of carrier signal

%XXXXXXXXXXXXXXXXXXXXXXXXXXXXXX AM Modulation XXXXXXXXXXXXXXXXXXXXXXXXXXXXX

m=Em/Ec; % modulation index

y= Ec*(1+m*cos(2*pi*fm*t)).*cos(2*pi*fc*t); % Equation of Amplitude modulated signal

%XXXXXXXXXXXXXXXXXXXXXXX Frequency Spectrum Of Modulated Signal XXXXXXXXXXX

N = length(y); %Number of samples

fs= 2*fc; % Sample frequency (Hz)

f =(0:N-1)*(fs/N); %frequency range(Hz)

% Double-sided amplitude spectrum

figure(2);

subplot(3,1,1);

Amp = abs(fftshift(fft(y))); %Amplitude of spectrum

plot(f, Amp, 'g')

xlabel('Frequency (Hz)')

ylabel('Amplitude');

title('Double-sideband frequency spectrum (Hertz)');

% Single-sided amplitude spectrum with frequency axis in Hertz

subplot(3,1,2);

Amp = abs(fft(y)); %Amplitude of modulated signal in Frequency spectrum

plot(f, Amp,'b');

xlabel('Frequency (Hz)')

ylabel('Amplitude');

title('Single-sideband frequency spectrum (Hertz)');

%>>>>>>>>>>>>>>>>>>>>>> end of program <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<

end

B = menu('Do you want to continue?','1.Yes','2.No');

switch B

case 1

z=1;

case 2

z=0;

end

end

As above is my code, I wish to obtain the correct frequency spectrum code for ssb and dsb but unfortunately, I couldn't get it.