for snr= 1:50
ber = err;
err=0;
No= 1/10^(snr/10);
    for i= 1: 10^6;
        x= sign (randn(2,1));
        h= randn (1,2) * sqrt(1/2) + sqrt (1/2)* 1j* randn(1,2);
        w= sqrt(No/2)* randn (1,2) + sqrt(No/2)*1j* randn(1,2);
        alamh=[ h(1) h(2); conj(h(2)) -conj(h(1))];
        y= alamh * x + transpose(w);
        h_pseudoinverse= inv(ctranspose(alamh)* alamh) ctranspose(alamh);
        r= x + h_pseudoinverse * transpose (w);
        est_x= sign(real(r));
        err= (est_x~=x)+err;
    end
ber(snr)= err/10^6;