%LMS自適應濾波器性能分析?
clear?
clc
close?all
%%%%%%%%%%%%%%參數設置%%%%%%%%%%%%%%%%%%%%%%%
w=3;
%?step_len=0.075;%步長
step_len=0.05;%步長

variance_v=0.01;%方差
repeat_times=20;%重復次數
iteration_times=500;%迭代次數
filt_len=2;%濾波器長度
delay=fix（filt_len/2）-1;
delay1=1;



%%%%%%%%%%%%%%%%%%%%變量及數組初始化%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
Chan_factor=（1+cos（2*pi*（[1:1:3]-2）/w））/2
Square_err=zeros（repeat_timesiteration_times）;
%?Chan_factor1=[-0.195?0.95]
Chan_factor1=[-0.195?0.95]
X=zeros（filt_len1）;
W1=[];
W2=[];
Wm1=[repeat_timesiteration_times];
Wm2=[repeat_timesiteration_times];


%%%%%%%%%%%%%外循環，重復做repeat_timws次實驗，平均值%%%%%%%%%%%%%%%%

for?loop1=1:repeat_times%循環次數
????
%%%%%%%%%%%%%%內循環變量及數組初始化%%%%%%%%%%%%%%%%%%%%%%%%
Source=zeros（iteration_times1）;
W=zeros（filt_len1）;

%%%%%%%%%%%%%內循環，做iteration_times次迭代%%%%%%%%%%%%%%%%%%%%%%%%%%%%
???for?i=1:iteration_times
%%%%%%%%%%%%%%信源，產生等概率分布的正負1%%%%%%%%%%%%%%%%%%%%%%%%%%%%
??????if?rand<0.5
??????????Source（i）=-1;
??????else
??????????Source（i）=1;
??????end
???end
%%%%%%%%%%%%%%信道，濾波和加噪聲%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
?Revdata=filter（Chan_factor11Source）+randn（iteration_times1）*sqrt（variance_v）;
%??Revdata=filter（Chan_factor1Source）+randn（iteration_times1）*sqrt（variance_v）;??
%????Revdata=filter（Chan_factor11Source）;
???
%?RT=filter（Chan_factor11Source）;
%%%%%%%%%%%%%%均衡器，基于LMS算法%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%????
????for?loop2=1:iteration_times-filt_len+1
????????
%?????????U=Revdata（loop2:loop2+filt_len-1）;
%??????????y（n）=W‘*U=W‘*x（n）U=x（n）=輸入
%??????????d為輸出
????????U=Source（loop2:loop2+filt_len-1）;
????????d=Revdata（loop2+1）;
%?????????d=Source（loop2+delay）;
%?????????X=?x（3）=v（3）-a1*x（2）-a2*x（1）;
????????
%???????????d=RT（loop2+delay1）;
%?????????Y（loop2）=W‘*U;
????????e=d-W‘*U;
%?????????e=d-W‘*U;
????????W=W+step_len*U*e;
????????
????????Wm1（loop2loop1）=W（1）;
????????Wm2（loop2loop1）=W（2）;
%?????????W1（loop2）=W（1）;
%?????????W2（loop2）=W（2）;
????????Square_err（loop1loop2）=e.^2;
????end
????
????
end



%%%%%%%%%%%%%%作圖，顯示結果%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
Square_err_mean=sum（Square_err（::））/repeat_times;
%?Wm2
W1=Wm1（:repeat_times）;
W2=Wm2（:repeat_times）;
meanW1=mean（Wm1‘）;
meanW2=mean（Wm2‘）;
Square_err;
%semilogy（Square_err_mean）;
figure（1）;
plot（Square_err_mean）;
hold?on;
plot（Square_err（1:）‘r‘）;
legend（‘20次重復試驗平均誤差‘‘單次誤差‘）;
xlabel（‘迭代次數‘）;
ylabel（‘均方誤差‘）;
title（‘步長為0.075，500次迭代均方誤差變化曲線‘）;
grid?on;
hold?on;

figure（2）;
plot（W1）;
hold?on;
plot（W2‘r‘）;
hold?on;
plot（meanW1‘k‘）;
hold?on;
plot（meanW2‘--k‘）;
legend（‘W1‘‘W2‘‘20次重復試驗W1‘‘20次重復試驗W2‘）;
xlabel（‘迭代次數‘）;
ylabel（‘抽頭權值‘）;
title（‘步長為0.075，500次迭代權值學習曲線‘）;
grid?on;

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

?????文件???????2939??2017-12-17?16:08??LMS濾波程序.m

?????文件???????2731??2017-12-17?16:09??RLS濾波程序.m

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

?????????????????5670????????????????????2