Coupling between coaxial cables at radio and microwave frequencies

The work reported here is concerned with measuring and trying to predict coupling between coaxial cables. The surface transfer impedance per unit length, ZT, is the parameter that determines how the signal gets into and out of the coaxial cables: this is measured in the frequency range from 100 kHz to several GHz in some cases. The third circuit, outside the coaxial cables, consists of the outers of the sending and victim cables and any other conducting and dielectric material in the vicinity. A lumped representation of the tertiary serves well at frequencies for which the length is less than a tenth of a wavelength; distributed circuit models are useful at all frequencies.