[TODO]傅立叶级数叠加合成周期矩形脉冲波形失败

%三角形式
%%使用傅立叶级数合成周期矩形脉冲。todo:失败
clc;
clear ;
close all;
%参数
E = 1;    %幅值
tao = 2;  %脉冲宽度
T = 5;    %总的周期
omega = 2*pi/T;
t = -10:0.01:10;
level = 100; %100阶合成
f = zeros(1,length(t));
for n = 0:level %阶数
    for s = 1 : length(t)
        if( n == 0 ) %第0阶
            f(s) = f(s)+ E*tao/T;
        end
        if( n > 0 ) %非0阶
            f(s) = f(s) + 2*E*tao*sinc(n*omega*tao/2)*cos(n*omega*t(s))/T;
        end
    end
end
figure(1);

plot(t,f);
title(‘三角函数形式100阶模拟\tau = 2 E = 1 T1 = 5‘);
axis([ -10 10 -0.1 1 ]);
set(gca,‘xtick‘,[-10:10]);

%指数形式
clc;
clear;
close all;
E = 1;
tao = 2;
T1 = 5;
w = 2*pi/T1;
t = -10:0.01:10;                %自变量区间
level = 100;                    %阶数
ft = zeros(1,length(t));        %函数值存放位置
for n = -level:level
    for s = 1:length(t);
        fn = E*tao/T1*sinc(n*w*tao/2);
        ft(s)=ft(s) + fn*exp(1i*w*n*t(s));
    end
end
figure();
plot( t , abs(ft));
title(‘指数函数形式100阶模拟\tau = 2 E = 1 T1 = 5‘);
axis([ -10 10 -0.1 1 ]);
set(gca,‘xtick‘,[-10:10]);