Sensitivity Analysis of Shielded Cables

摘要

Using a shielded pair design as an example, the normalized sensitivities of cable propagation properties are calculated for selected dimensional and material parameters of the cable. It is demonstrated that higher impedance cables are less sensitive to all dimensional parameters and can be manufactured with higher manufacturing tolerances at lower costs. Targeting higher impedances of the allowable impedance range produces a better cable, with less copper, lower attenuation and more stable parameters. For the selected geometry and materials, the 115 Ohm design offered an optimal balance between the characteristic impedance and resistance with the lowest attenuation. A method for estimation of expected tolerance of cable propagation properties based on available manufacturing tolerances and calculated sensitivities is suggested.