main_03_pjm

######  시간/주파수 베이스 Power Sum 구하기 및 hanning window에 의한 비교
######  2025. 04. 07. pjm, 5th, ECO
clc; clear; close all;

dt = 1e-4;
N = 2e4;
t = [1:N]*dt;
df = 1/t(end);


#### Org.
acc = Rand_Harm_Sigs( t , 5 );            ## acc( 1,N ary )
[ Acc_mir, f ] = two_side_fft( acc, t );  ## Acc_mir( 1,N ary )  / ## f( 1,N ary )
Auto_PS_mir = conj(Acc_mir) .*Acc_mir;    ## Auto_PS_mir( 1,N ary )

PS_time = PowerSum( acc,dt );
PS_freq = PowerSum( Acc_mir,1/df );
ratio_PS_org = PS_freq/PS_time;

#### hanning wind w/o coef.
acc_hann = acc .* hanning(N).';
[ Acc_mir_hann, f ] = two_side_fft( acc_hann , t );   ## Acc_mir_hann( 1,N ary )  / ## f( 1,N ary )
Auto_PS_mir_hann = conj(Acc_mir_hann) .*Acc_mir_hann; ## Auto_PS_mir_hann( 1,N ary )

%PS_time_hann = PowerSum( acc_hann,dt );
PS_freq_hann = PowerSum( Acc_mir_hann,1/df );
ratio_PS_hann_wo = PS_freq_hann/PS_time;


#### hanning wind w. coef.
Acc_mir_hann_ecf = sqrt(8/3)*Acc_mir_hann;   ## Acc_mir_hann( 1,N ary )  / ## f( 1,N ary )
Auto_PS_mir_hann_ecf = conj(Acc_mir_hann_ecf) .*Acc_mir_hann_ecf; ## Auto_PS_mir_hann( 1,N ary )

%PS_time_hann = PowerSum( acc_hann,dt );
PS_freq_hann_ecf = PowerSum( Acc_mir_hann_ecf,1/df );
ratio_PS_hann_ecf = PS_freq_hann_ecf/PS_time;

#### Power Sum 결과 비교  ( Sum of PowerSpectrum / raw_data )
#### raw_data가 랜덤이므로 오차율 변동할 수 있음
%ratio_PS_org      = 1.0000
%ratio_PS_hann_wo  = 0.3751
%ratio_PS_hann_ecf = 1.0004


figure(1,'position',[300 200 800 600],'defaultaxesfontsize',14)
hold on; grid on; grid minor;
plot(t,acc,';no wind;')
ylabel('Acc. [m/s^2]'); xlabel('Time [sec]')
hold off

figure(2,'position',[300 200 800 600],'defaultaxesfontsize',14)
hold on; grid on; grid minor;
plot(f,Auto_PS_mir,';no wind;','linewidth',3)
plot(f,Auto_PS_mir_hann,';hanning w/o coef.;','linewidth',2)
plot(f,Auto_PS_mir_hann_ecf,';hanning w. coef.;','linewidth',1)
ylabel('Mag. [(m/s^2).^2]'); xlabel('Freq. [Hz]')
hold off