function VTB7_1

%VTB7_1 is an example of taking a power spectral density
% of data. The power spectral density of a signal containing
% .5 Hz and 1.59 Hz signals is plotted.

t=0:.1:100;t=t';

y=sin(pi*t)+sin(10*t);

plot(t,y);

title('Sin(pi*t)+Sin(10*t) versus Time')

xlabel('Time')

ylabel('F(t)')

x=fft(y,512);

text(0,0,'Press Return To Continue','sc')

pause

Pyy=x.*conj(x)/512;

f=10*(0:255)/512;

plot(f,Pyy(1:256))

title('Power Spectral Density of F(t)')

xlabel('Frequency (Hz)')

ylabel('Power Spectral Density')

text(0,0,'Press Return To Continue','sc')

pause