Scattering data in an inverse scattering problem on the semi-axis for a first-order hyperbolic system

The inverse scattering problem for the first-order hyperbolic system on the semi-axis in the case of 2 incident and 2 scattered waves under consideration of 2 problems with the same given incident waves and different boundary conditions is considered. The scattering data on the semi-axis are given in terms of the scattering operator on the whole axis for the same system with the coefficients, which are extended in the whole axis by zero.