function plot_power_spectrum(ps,points,new,col);
%function plot_power_spectrum(ps,points,new,col);
%ps: power spectrum to be plotted
%points: number of pulse samples in [0,T)
%new: 1=build a new figure, 0 plot on existing one
%col: color (a character)
warning off
f=0:points/(length(ps)+1):points/4;
if new
	h0=figure;
    length(ps)
	f=0:points/(length(ps)+1):points/4;
	h1 = axes('Parent',h0, ...
          'YLimMode','manual', ...
          'YLim',[-80, 0], ...
          'XLimMode','manual', ...
          'XLim',[0, f(length(f))]);

   hold;
else
   hold;
end
fi=1:length(f);
plot(f,10*log10(ps(fi)/max(ps)),col)
xlabel('fT');
ylabel('power spectrum [dB]'); 
warning on
hold;