On the measurement of far field intensities generated by cables shielded with composites showing electromagnetic losses

Abstract

Electromagnetic compatibility is a significant problem for electronic system developers, especially cabling, which is often the weakest link of the assembly, therefore a bigger emphasis is put on its securing. Recently, a significant progress has been achieved in synthetic electromagnetically lossy materials. Therefore, new cable designs using these cable sheath materials can be soon expected both in applied research and in development. At the same time, reliable measurements of such shielding effectiveness are needed, especially in terms of the far field. While most publications about synthetic electromagnetic lossy materials deal with their measurement via coaxial transmission lines (the ASTM method), far-field measurements have not been sufficiently discussed. In this paper, several phenomena related to this topic are discussed, further, an experiment testing two different cable specimens is realized and the results are compared. The paper discusses fundamental issues of far EM field generated by power supply cables fed by radio frequency interferences.