lsb_error_new.m

Hierarchical－QAM的程序

function [err_value] = lsb_error_new(theta_input_vector, snr)
% This function calculates the BER for the LSB.

theta_input_vector;
n=length(theta_input_vector);
%if(n>2)
bound_vector=zeros(n-1, 1);
for i=1:n-1
    bound_vector(i,1)=theta_input_vector(i,1);
end

% Creating Boundaries
%bound=zeros(2^(n-1),1);
a=zeros(2^(n),1);
%b=zeros(2^(n),1);
x=1; y=1;
for i=2^(n-2):2^(n-1)-1
    index=i;
    mult=zeros(1, n-1);
    for j=n-1:-1:1
        mult(1,j)=2*mod(index,2)-1;
        index=floor(index/2);
    end;
    a(i+1-2^(n-2),1)=mult*bound_vector;
    
 %   if(mult(n-1,1)==1)
 %       b(x,1)=bound_vector*mult;
 %       x=x+1;
 %   else
 %       a(y,1)=bound_vector*mult;
 %       y=y+1;
 %  end;
end;
%x%
%y
for i=1:2^(n-2)
    a(i+2^(n-2),1)=pi-(a(2^(n-2)+1-i,1));
 %   b(i+2^(n-2),1)=pi-(b(2^(n-2)+1-i,1));
end;
for i=2^(n-1)+1:3*2^(n-2)
    a(i,1)=a(i-2^(n-1),1)-pi;
 %   b(i,1)=b(i-2^(n-1),1)-pi;
end;
for i=1:2^(n-2)
    a(i+3*2^(n-2),1)=-a(2^(n-2)+1-i, 1);
%    b(i+3*2^(n-2),1)=-b(2^(n-2)+1-i, 1);
end;

%%%%% Vectors a and b are ready. Now calculate the actual phi vectors.

phi=zeros(2^(n+1), 1);
phi_0=zeros(2^(n), 1);
phi_1=zeros(2^(n), 1);
%x=1;y=1;
for i=2^(n-1):2^(n)-1
    index=i;
    mult=zeros(1,n);
    for j=n:-1:1
        mult(1,j)=2*mod(index,2)-1;
        index=floor(index/2);
    end;
%    if(mult(n,1)==1)
%        phi_1(x,1)=theta_input_vector*mult;
%        x=x+1;
%    else
%        phi_0(y,1)=theta_vector*mult;
%        y=y+1;
%    end; 
theta_input_vector;
mult;
    phi(i+1-2^(n-1),1)=mult*theta_input_vector;
end;

for i=1:2^(n-1)
    phi(i+2^(n-1),1)=pi-phi(2^(n-1)+1-i,1);
%    phi_1(i+2^(n-2),1)=pi-phi_1(i,1);
end;
for i=1:2^(n)
    phi(i+2^(n), 1)=-phi(2^(n)+1-i, 1);
end;


phi_0(1,1)=phi(1,1);
x=2;y=1;
while(x < 2^(n+1)-2)
   phi_1(y,1)=phi(x,1);
   phi_1(y+1,1)=phi(x+1,1);
   phi_0(y+1,1)=phi(x+2,1);
   phi_0(y+2,1)=phi(x+3,1);
   x=x+4;
   y=y+2;
end;
phi_1(y,1)=phi(x,1);
phi_1(y+1,1)=phi(x+1,1);
phi_0(y+1,1)=phi(x+2,1);

a;
phi;
phi_0;
phi_1;

%%%%% Now the phi vectors are ready. Calculate the Error
err=0;
for j=1:1:2^(n)
    for i=1:2:2^(n)-1  
        err=err+F_func(snr, a(i+1,1)-phi_0(j,1))-F_func(snr, a(i,1)-phi_0(j,1));
    end;
    err;
end;

for j=1:1:2^n
    for i=2:2:2^(n)-1
        err=err+(F_func(snr,a(i+1,1)-phi_1(j,1))-F_func(snr,a(i,1)-phi_1(j,1)));
    end;
    err=err+F_func(snr,a(1,1)-phi_1(j,1))-F_func(snr,a(2^n,1)-phi_1(j,1));
    err;
end;
    
    %else
    %err=F_func(snr, -theta_input_vector(2))+F_func(snr, pi-theta_input_vector(2)) + 0.5*(F_func(snr, 2*theta_input_vector(1)+theta_input_vector(2))-F_func(snr, pi-2*theta_input_vector(1)-theta_input_vector(2)))-0.5*(F_func(snr, 2*theta_input_vector(1)-theta_input_vector(2))-F_func(snr, pi-2*theta_input_vector(1)+theta_input_vector(2)));
    %end;        

err_value=err/(2^(n+1));