www.pudn.com > zxb.rar > sepfilter.m

function [BT1,BT2]=sepfilter(S,P,V,NFFT) 
 
NF = NFFT/2+1; 
 
for f=1:NF, 
  f1=2*f-1; f2=2*f; 
  if S(f)==1, 
    TMPV=inv(V(f1:f2,:)); 
    if P(f)==1, 
      TMPV=flipud(TMPV); 
    end 
    TMPINV=inv(TMPV); 
    BF1=TMPINV(:,1)*TMPV(1,:); BF2=TMPINV(:,2)*TMPV(2,:); 
  else 
    if P(f)==0, 
      BF1=eye(2); BF2=zeros(2); 
    else 
      BF1=zeros(2); BF2=eye(2); 
    end 
  end 
 
  BF1_11(f)=BF1(1,1); BF1_12(f)=BF1(1,2); 
  BF1_21(f)=BF1(2,1); BF1_22(f)=BF1(2,2); 
 
  BF2_11(f)=BF2(1,1); BF2_12(f)=BF2(1,2); 
  BF2_21(f)=BF2(2,1); BF2_22(f)=BF2(2,2); 
end 
 
BF1_11(NF+1:NFFT)=conj(fliplr(BF1_11(2:NF-1))); 
BF1_12(NF+1:NFFT)=conj(fliplr(BF1_12(2:NF-1))); 
BF1_21(NF+1:NFFT)=conj(fliplr(BF1_21(2:NF-1))); 
BF1_22(NF+1:NFFT)=conj(fliplr(BF1_22(2:NF-1))); 
   
BF2_11(NF+1:NFFT)=conj(fliplr(BF2_11(2:NF-1))); 
BF2_12(NF+1:NFFT)=conj(fliplr(BF2_12(2:NF-1))); 
BF2_21(NF+1:NFFT)=conj(fliplr(BF2_21(2:NF-1))); 
BF2_22(NF+1:NFFT)=conj(fliplr(BF2_22(2:NF-1))); 
   
BT1(1,:)=ifft(BF1_11); BT1(2,:)=ifft(BF1_12); 
BT1(3,:)=ifft(BF1_21); BT1(4,:)=ifft(BF1_22); 
BT2(1,:)=ifft(BF2_11); BT2(2,:)=ifft(BF2_12); 
BT2(3,:)=ifft(BF2_21); BT2(4,:)=ifft(BF2_22); 
   
BT1=real(BT1); BT2=real(BT2);