Computationally-effective wideband worst-case model of transmission line radiation

The analytical model for radiation of a rectilinear uniform transmission line placed above a conducting screen is proposed. The model is intended for diagnostics (express analysis) of unintentional interference in large complexes of radio and electronic equipment. The model makes it possible to compute the envelopes of the amplitude-frequency characteristics for electric and magnetic fields in any spatial point above the screen. Single wire above ground plane, coaxial and triaxial lines with various grounding configurations are considered. The model is based on replacement of the complicated transmission line by an equivalent (in terms of the radiated field) single wire over ground plane. Correctness of the proposed model was verified by comparison with numerical simulation results in the frequency band from 10 kHz to 2 GHz for lines of length from 5 cm to 10 m with various load and source impedances, the line height above the ground plane was varied from the radius of the line to 5 m, the observation point position was up to 5 m away from the center of the line in arbitrary direction.