σCu D

The attenuation of a coaxial cable can be calculated by means of transmission line theory1, which extends the description of discrete electronic components to distributed elements. For a coaxial cable with resistance Rtot [Ω/m], given by the sum of inner and outer conductor resistance RIC and ROC, with inductance L [H/m], capacitance C [F/m] and shunt conduc-tance G [S/m] (note that all parameters are per length), the attenuation in units of decibel as a function of frequency ν reads: Attenuation(ν) = 20 log ∣∣e−γz∣ ∣ , γ = √(Rtot + 2piiνL)(G+ 2piiνC) (1) Here, z denotes the wire length in units of m. Parameters Rtot, L, C and G may be calculated from geometric dimensions of the coaxial cable (inner conductor diameter D, thickness dIns. of the polyurethane insulation and depoxy for the epoxy outer conductor), and material properties such as the dielectric constant Ins. of the polyurethane insulation and the conductivity σCu, σepoxy, σIns. of inner conductor, outer conductor and the insulator, respectively