clc
clear
close?all
choosetype=1;
%??1?BOXCAR;2?BARTLETT;?3?HANN;4?HAMMING;?5?BLACKMAN;
?choose=4;
?%1?lp;2?hp;3bp;4bs
switch?choose
case?1????
wp=2*pi;
ws=4*pi;
s=20;
width=（ws-wp）/pi/s;
wc=（wp+ws）/2/pi/s;
case?2
?wp=4*pi;
ws=2*pi;
s=20;
width=（wp-ws）/pi/s;
??wc=0.5-（wp+ws）/2/pi/s;
case?3
????wsl=2*pi;
????wsh=12*pi;
????wpl=4*pi;
????wph=8*pi;
????s=25;
????wcl=（wsl+wpl）/2/pi/s;
????wch=（wsh+wph）/2/pi/s;
????F0=（wpl+wph）/2/pi/s;
???wc=（wsh+wph）/2/pi/s-F0;
????width=min（（wpl-wsl）（wsh-wph））/pi/s;
case?4
????wpl=2*pi;
????wph=8*pi;
????wsl=4*pi;
????wsh=6*pi;
????s=10;
????wcl=（wsl+wpl）/2/s;
????wch=（wsh+wph）/2/s;
????F0=（wsl+wsh）/2/pi/s;
????wc=（wsh+wph）/2/pi/s-F0;
????width=min（（wsl-wpl）（wph-wsh））/pi/s;
end


switch?choosetype
???????case?1
?????????N=13;
????????type=BOXCAR（N）;?
????????titl=‘BOXCAR‘;
????????f=abs（fft（type1024））;
?????????f=10*log（f）;
?????????
????????case?2
????????N=31;
????????type=BARTLETT（N）;
????????titl=‘BARTLETT‘;
????????f=abs（fft（type1024））;
?????????f=10*log（f）;
????????case?5
????????N=ceil（5.71/width）;
????????type=BLACKMAN（N）;
????????titl=‘BLACKMAN‘;
????????f=abs（fft（type1024））;
?????????f=10*log（f）;?????
????????case?4
?????????N=ceil（3.47/width）;
????????type=HAMMING（N）;
????????titl=‘HAMMING‘;
????????f=abs（fft（type1024））;
?????????f=10*log（f）;???
????????case?3
?????????????N=ceil（3.21/width）+1;
????????type=HANN（N）;
????????titl=‘HANN‘;
?????????f=abs（fft（type1024））;
?????????f=10*log（f）;????????
end

window=type.‘;
n=0:N-1;
tao=（N-1）/2;
switch?choose
case?1
hd=?2*wc*sinc（2*wc*（n-tao））;
case?2
????hd=2*wc*（-1）.^（n-tao）.*sinc（2*wc*（n-tao））;
case?3
????hd=4*wc*sinc（2*（n-tao）.*wc）.*cos（2*pi*（n-tao）.*F0）;
case?4
%??????hd=（n==tao）-4*wc*sinc（2*（n-tao）.*wc）.*cos（2*pi*（n-tao）.*F0）;
hd=sin（pi/3*（n-tao+eps））./（pi*（n-tao+eps））+sin（pi*（n-tao+eps））./（pi*（n-tao+eps））-sin（2*pi/3*（n-tao+eps））./（pi*（n-tao+eps））;
end
h=hd.*window;
H=abs（fft（h1024））;
mag=abs（H）;
db=20*log10（（mag+eps）/max（mag））;
%?figure
%?subplot（211）
%?stem（type）
%?grid?on
%?subplot（212）
%?plot（f）
%?grid?on
figure
plot（[0:1023]/1024db）
grid?on
title（titl）;

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----

?????文件???????2201??2006-06-19?10:30??FIRwin.m

-----------?---------??----------?-----??----

?????????????????2201????????????????????1