Twin-axial cable with novel structure and method for testing intra-pair transmission skew

Abstract

The invention provides a twin-axial cable with novel structure and a method for testing intra-pair transmission skew. The twin-axial cable comprises a wire pair and a sheath layer. The wire pair comprises two conductive core wires, each of the conductive core wires comprises an inner conductor and an insulating layer outside the inner conductor, and the wire pair is characterized in that a shielding layer is arranged outside the insulating layer of each of the conductive core wires. A drain wire is arranged in a gap between the wire pair, a wire pair shielding unit is arranged outside the wirepair, and a sheath layer is arranged outside the wire pair shielding unit. Single core wires which form the wire pair has shielding respectively, and the intra-pair transmission skew is optimized. The invention provides the method for testing the intra-pair transmission skew, and in order to simulate the possible change of the intra-pair transmission skew in actual use, a test procedure is simplified. The twin-axial cable has the advantages of low attenuation, small intra-pair transmission skew, uniform differential impedance and good social and economic benefits.

Description

technical field [0001] The invention relates to a parallel double-conductor cable for digital communication in the field of communication transmission, in particular to a parallel double-conductor cable with low attenuation, small transmission delay difference between pairs of wires, and uniform differential impedance. The core wire conductors of the wire pairs in the cable are silver-plated round copper Wire or tinned copper wire or bare round copper wire, core wire insulation can be solid, foam or microporous PTFE insulation, drain wire conductor is silver plated round copper wire or tinned round copper wire or bare round copper wire, The single-core shielding layer is a metal composite tape inside, and a metal wire braiding layer is added, and a layer of metal composite tape is wrapped longitudinally outside the wire as a wire pair shield. The sheath layer can be directly extruded with an 8-shaped sheath, and finally made into a Parallel twin-conductor cable of new construc...

AI Technical Summary

Problems solved by technology

[0004] Since the effective dielectric constant of the core wire insulation depends not only on the manufacturing level of a single core wire (mainly the uniformity of core wire foaming, the thickness and eccentricity of the insulating layer, and the uniformity of the conductor diameter), it is also affected by the shielding of the wire pair and the grounding of the shielding of the wire pair. The influence of the line on the capacitance and inductance of a single core wire, that is, the distance between the two core wires and the wire pair shield, the distance between the wire pair shield and the ground wire is different, the position of the two core wire pairs is asymmetrical, and the air gap between the core wire and the shield is different. Both will cause the difference in the effective dielectric constant of the insulation of the two core wires, which is an important reason for the delay difference within the line pair, and also makes the differential impedance of the line pair deviate from 100Ω

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