function Fre_Est=Base_Esprit_1_Ls(x,p,array_n,num)
%x:input real signal
%p:the numble of the signal
%m:the numble of the array attena
N=length(x);
r=xcorr(x,'biased');
R_xx=zeros(array_n,array_n);
R_xy=zeros(array_n,array_n);
for m=0:array_n-1
    R_xx(m+1,:)=r(N-m:N-m+array_n-1);
	R_xy(m+1,:)=r(N-m+1:N-m+array_n);
end 
rank=p;
[u,s,v]=svd(R_xx);
m=mean(diag(s(rank+1:end,rank+1:end)));
s=s-m*eye(array_n);
C_xx=u*s*v.';
z=[zeros(1,array_n);eye(array_n-1,array_n)];
C_xy=R_xy-m*z;
v=eig(R_xx,R_xy);
frequency=abs(angle(v)/2/pi);
Fre_Est=Find_Numble(frequency,num);