echo on
T=1;M=8;Es=T/2;fc=6/T;
N=120;delta_T=T/(N-1);t=0:delta_T:T;
u0=sqrt(2*Es/T)*cos(2*pi*fc*t);
u1=sqrt(2*Es/T)*cos(2*pi*fc*t+2*pi/M);
u2=sqrt(2*Es/T)*cos(2*pi*fc*t+4*pi/M);
u3=sqrt(2*Es/T)*cos(2*pi*fc*t+6*pi/M);
u4=sqrt(2*Es/T)*cos(2*pi*fc*t+8*pi/M);
u5=sqrt(2*Es/T)*cos(2*pi*fc*t+10*pi/M);
u6=sqrt(2*Es/T)*cos(2*pi*fc*t+12*pi/M);
u7=sqrt(2*Es/T)*cos(2*pi*fc*t+14*pi/M);
u=u0.*u1.*u2.*u3.*u4.*u5.*u6.*u7;
subplot(5,1,1);plot(t,u0);
subplot(5,1,2);plot(t,u1);
subplot(5,1,3);plot(t,u2);
subplot(5,1,4);plot(t,u3);
subplot(5,1,5);plot(t,u);