function?[input_signal?error_signal?desired_signal?filter_output?impulse?filter_current?mse?db?db_avg]=LMS（filter_size?step_size?input_file?iterations）
%?Function?to?perform?the?LMS?algorithm?on?an?input?file.
%?Inputs:???Filter?order?step?size?input?wav?file?number?of?iterations.
%?Outputs:??Input?signal?error?estimation?signal?（echo?cancelled）?desired?signal?（echoed?signal）?adaptive?filter?output?real?impulse?response
%???????????Estimation?of?impulse?response?mean?sqaure?error?attenuation?（dB）?average?attenuation.

%Read?in?the?input?file
input_signal?=?wavread（input_file30000）;
%?Create?the?impulse?response?for?the?desired?signal
impulse=zeros（filter_size1）;
for?（i=1:5）?%#ok
????impulse（（（i-1）*filter_size/5）+1）=3/i;????
end

%?Convolve?the?impulse?with?the?input?signal?to?generate?the?desired?signal
desired_signal?=?conv（input_signal?impulse）;

%?initialise?adaptive?filter?impulse?and?input?vector?to?zero?vector?of?length?specified?at?command?line
filter_current?=?zeros（filter_size1）;
input_vector?=?zeros（filter_size?1）;

%?Loop?for?number?of?iterations?specified?in?command?line.
for?i=1:iterations;
????%i;#ok
????input_vector（1）=input_signal（i）;?????????%?insert?new?sample?at?beginning?of?input?vector.
????filter_output（i）=dot（filter_current?input_vector）;??????????%#ok?%Caluclate?adaptive?filter?output
????error=?desired_signal（i）-filter_output（i）;???????%?Calculate?estimation?error
????filter_current?=?filter_current?+?2*step_size*error*input_vector;???????%?Update?filter?taps?by?LMS?recursion
????
????%?Shfit?values?ion?vector?along.
????for?j=filter_size:-1:2;
????????input_vector（j）=input_vector（j-1）;????
????end
????
????error_signal（i）=error;??????%#ok?%?store?estimation?error
????cost（i）=error*error;????????%#ok?%?calculate?instantaneous?cost?sqaure?error
????
????if?（i==1）
?????????fc0=filter_current;?????%#ok
????end
????if?（i==7500）
?????????fc1=filter_current;?????%#ok
????end
????if?（i==15000）
?????????fc2=filter_current;?????%#ok
????end
????if?（i==22500）
?????????fc3=filter_current;?????%#ok
????end
????if?（i==30000）
?????????fc4=filter_current;?????%#ok
????end
end

%?Find?moving?average?of?error?squared.
for?i=1:iterations-100;
????mse（i）=mean（cost（i:i+100））;?%#ok
?????%i#ok
end

%find?moving?avarage?of?db?attenuation?（averaged?to?smooth?output）.
for?i=1:iterations-2500;
????db（i）=-20*log10（mean（abs（desired_signal（i:i+2500）））‘./mean（abs（error_signal（i:i+2500））））;?%#ok
?????%i;#ok
end

%find?total?avarage?db?attenuation
db_avg=mean（db）;

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

?????文件?????204346??2010-12-07?20:19??自適應算法\自適應算法\ll.wav

?????文件???????2693??2010-12-07?20:31??自適應算法\自適應算法\LMS.m

?????文件???????2122??2010-12-07?20:48??自適應算法\自適應算法\NLMS.m

?????文件???????2507??2010-12-07?20:54??自適應算法\自適應算法\RLS.m

?????文件???????2847??2010-12-07?21:06??自適應算法\自適應算法\VSLMS.m

?????文件???????2834??2010-12-07?21:14??自適應算法\自適應算法\VSNLMS.m

?????文件?????308424??2011-01-15?17:00??自適應算法\自適應算法\Adaptive_Filter_Design（NO.3）.pptx

?????目錄??????????0??2011-01-15?16:54??自適應算法\自適應算法

?????目錄??????????0??2011-01-15?16:59??自適應算法

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

???????????????525773????????????????????9