Approximate determination of the impulse responses of a system of telegraph equations

Systems of telegraph equations govern the voltages and currents in closely spaced long parallel wires (coupled or multiconductor transmission lines). The impulse response is defined as the waveforms of the voltages and currents produced at the output on applying the deltalike signal at the input. It is proved that the impulse response consists of two terms: a sum of delta functions and a usual function $N$. An explicit formula is given for the first term, and an approximate determination method is proposed for calculating $N$.