  The robustness of Bell's inequality (in CHSH form) violation by entangled
state in the simultaneous presence of colored and white noise in the system is
considered. A twophoton polarization state is modeled by twoparameter density
matrix. Setting parameter values one can vary the relative fraction of pure
entangled Bell's state as well as white and colored noise fractions. Bell's
operator-parameter dependence analysis is made. Computational results are
compared with experimental data [quant-ph/0511265] and with results computed
using a oneparameter density matrix [doi: 10.1103/PhysRevA.72.052112], which
one can get as a special case of the model considered in this work.
