Psi(t) Umod(t). ( ) Mp = 15.
3.7 -
Mp = 15;
Uo = 1; Um = 2; T = 1e-3;Un = 1; Fn = 4e4;
t =(0:1e-3:0.3)*1e-3;
Umod = cosinobn1(t,Um,T,Uo); Up = Un*cos(Psi);
Psi = 2*pi*Fn*t+Mp*Umod'; plot(t,Up,t,Umod)
( 3.8) . MATLAB fft, 2N, 210 = 1024 .
3.8 -
K = 1024; t = linspace(0,4*T,K);
df = 1/(4*T);
Umod = cosinobn1(t,Um,T,Uo);
Psi = 2*pi*Fn*t+Mp*Umod';
Uph = Un*cos(Psi);
Sph = fft(Uph)/K;
plot(df*(1:512),abs(Sph(1:512)))
3.9 -
Eph=cumsum(abs(Sph(1:512)).^2);
Gr1=0.95*Eph(end)*ones(1,512); % 0.95
plot(df*(1:512),Eph,df*(1:512),Gr1)
. . , 1/4 = 250 , 0.95 58.9 , 0.05 21 .
5% 95% ( 2.9) : , , .