Numerical Electromagnetic Field Analysis of High-Frequency Wave Propagation on an Overhead Conductor

The wave propagation characteristics on an overhead conductor in a high-frequency band were investigated based on the Wise's earth-return admittance and modified Pollaczek's (accurate) earth-return impedance in a previous paper. In this paper, the characteristics are studied using the numerical electromagnetic code (NEC), which is based on the method of moments in the frequency domain. Results computed using NEC show quite similar characteristics to those described in the previous paper, i.e., a transition between transverse electromagnetic and transverse magnetic propagation called Sommerfeld-Goubau propagation. Thus, the mode transition has been confirmed. Also, observation indicates that Wise's admittance and an accurate impedance (transmission line approach) are applicable to investigating high-frequency wave propagation on an overhead horizontal conductor, as Kikuchi pointed out.