A Full-Wave-Transmission-Line Hybrid Method for Vertically Laid Shielded Cable Illuminated by HEMP

A hybrid method of full-wave-transmission-line approach is established to calculate the transient response of the shielded cable vertically laid to the ground when illuminated by a high-altitude electromagnetic pulse. In the approach, the induced current on the external sheath is evaluated by Holland's thin-wire finite-difference time-domain method, while the response of the inner conductor is solved by the classic transmission-line method at the same time. Using the proposed approach, the termination currents of both conductors are computed and analyzed to conclude the general rules and waveform characteristics in the specified situation. Evaluated results show that the hybrid method gets good accuracy and efficiency, and the variations of the currents with several parameters are studied.