clc close all clear all fs1002000 ts1fs t01ts01ts Nolengtht

clc

close all;

clear all;

fs=100*2000;

ts=1/fs;

t=-0.1:ts:0.1-ts;

No=length(t)

x=2*cos(2*pi*2000*t);

y=fmmod(x,100000,100*2000,10000);

Y=abs(fftshift(fft(y)/No));

f=[-No/2:No/2-1]/(No*ts);

figure(1)

plot(x)

title(\'x(t) in time domain\')

ylabel(\'Amplitude\')

xlabel(\'Time(s)\')

figure(2)

subplot(221)

plot(f,Y)

title(\'y(w) in frequency domain\')

ylabel(\'Magnitude\')

xlabel(\'Frequency(Hz)\')

subplot(222)

plot(y)

title(\'y(t) in time domain\')

ylabel(\'Amplitude\')

xlabel(\'Time(s)\')

if i have a code as above how can i use cumsum() command instead of fmmod to get the same result ?

Solution

clc

close all;

clear all;

fs=100*2000;

ts=1/fs;

t=-0.1:ts:0.1-ts;

N=length(t);

x=2*cos(2*pi*2000*t);

%%%%%%%%%%%%%%%%%%%%%%%%

len=size(x,1);

int_x = cumsum(x)*ts;

y = cos((2*pi*100000*t )+ (2*pi*10000*int_x) + 0);

if(len == 1)

y = y\';

end

%%%%%%%%%%%%%%%%%%%%%%%%%%%

Y=abs(fftshift(fft(y)/N));

f=[-N/2:N/2-1]/(N*ts);

figure(1)

plot(x)

title(\'x(t) in time domain\')

ylabel(\'Amplitude\')

xlabel(\'Time(s)\')

figure(2)

subplot(221)

plot(f,Y)

title(\'y(w) in frequency domain\')

ylabel(\'Magnitude\')

xlabel(\'Frequency(Hz)\')

subplot(222)

plot(y)

title(\'y(t) in time domain\')

ylabel(\'Amplitude\')

xlabel(\'Time(s)\')

%Please feel free to ask any problem. This code will give you exactly the same .. Please rate me if u like the response. Thanks