clc
t1 = xlsread('Step_20_25.xlsx','N103:N30002');  
VO = xlsread('Step_20_25.xlsx','AH103:AH30002');
Ptop = xlsread('Step_20_25.xlsx','AF103:AF30002');
Pbuff = xlsread('Step_20_25.xlsx','Z103:Z30002');
t2 = xlsread('acc_step_20_25.xlsx','B2:B600002');
acc = xlsread('acc_step_20_25.xlsx','C2:C600002');
figure (1)
clf
subplot(411);
plot(t1,VO,'m'); 
ylabel('Valve Opening','FontSize',14);
title('Step response Test 1','FontSize',14);
grid on
hold on
subplot(412);
plot(t1,Ptop,'r'); 
ylabel('Top Pressure','FontSize',14);
grid on
hold on
subplot(413);
plot(t1,Pbuff,'b');
ylabel('Buffer Pressure','FontSize',14);
grid on
hold on
subplot(414);
plot(t2,acc,'b');
ylabel('Acoustic Signal','FontSize',14);
xlabel('time(s)','FontSize',14);
grid on
hold on