In framework of the perturbed "sine-Gordon" equation and its nonlinear two-phase nonlinear wave solutions with slowly changing parameters (wave vectors and frequencies) we have described magnetic and electric properties of the tunnel junction consisting of two superconductors separated by an insulate barrier (SIS structure). On basis of the energy balance equation we have built the current-voltage characteristic of the tunnel junction. It is shown that the current-voltage curve consists of a system of spikes at the resonance voltages with their amplitudes modulated by the external magnetic field.