Nonlinear unequal error-protection codes are sometimes better than linear ones

The parameters of some binary nonlinear two-level unequal error-protection (UEP) codes are evaluated and compared with nonexistence bounds for linear UEP codes. The major points is that for UEP codes linearity is an essential restriction. The results demonstrate that at least in certain cases nonlinear codes perform better than linear ones. This is in contrast to the situation for ordinary codes, when in most cases the best possible result can be obtained even with the restriction of linearity