How can I make a square wave using Fourier synthesis?

I'm can't seem to figure out how to plot this.

f(t)=4/π ∑_n^∞ 1/n*sin(nωt)

n=1,3,5....

n=1=1Hz

t=0:0.001:3

Any help would be much appreciated, thanks.

Answer 1

[Image Analyst]

Try this:

clc;    % Clear the command window.
close all;  % Close all figures (except those of imtool.)
workspace;  % Make sure the workspace panel is showing.
format long g;
format compact;
fontSize = 20;

t=0:0.01:3;
omega = 2*pi;
f = zeros(1, length(t));
for n = 1 : 2 : 201
  f = f + (4/pi) .* 1 ./ n * sin(n * omega * t);
end
plot(t, f, 'b*-', 'LineWidth', 2, 'MarkerSize', 10);
grid on;
xlabel('t', 'fontSize', fontSize);
ylabel('f', 'fontSize', fontSize);
title('Square Wave Approimation', 'fontSize', fontSize);

% Set up figure properties:
% Enlarge figure to full screen.
set(gcf, 'Units', 'Normalized', 'OuterPosition', [0 0 1 1]);
% Get rid of tool bar and pulldown menus that are along top of figure.
set(gcf, 'Toolbar', 'none', 'Menu', 'none');
% Give a name to the title bar.
set(gcf, 'Name', 'Demo by ImageAnalyst', 'NumberTitle', 'Off')

[Image Analyst]

Jimmy, is this what you were looking for?

[JimmyJazz]

Yeah, that's great! Thanks man!

Answer 2

[Walter Roberson]

You need an infinite number of points to synthesize a square wave using fourier synthesis.

[JimmyJazz]

I'm trying to plot a pseudo continuous wave, say n=1:2:200.

[Walter Roberson]

for loop. or arrayfun. Or bsxfun. Or ndgrid.

Answer 3

[Aditya Sharma]

%% Generation of squarewave from Fourier Synthesis
close all
clear all
clc
Fs = 400; %samples per second
Ts = 1 / Fs; % sampleing interval
t = 0; Ts:3-1*Ts;
fm= 3;
%squarewave using MATLAB function
x = square(2*pi*fm*t);
plot(t,x);
axis( [0 1 -2 2 ] )
hold on
y=0;
n= input(' enter no of samples ');
for i =1:2:n
    y = y+ sin( 2*pi*fm )

[Walter Roberson]

Your code is missing an end statement.

You should be taking sin(2*pi*fm*t)