EP0848390B1 - Contact-pairs assembly of double lines and of multi-conductor cable-lines for cross-talk reduction - Google Patents

Description

The invention relates to an arrangement of contact pairs of double lines and cables of a multicore cable to reduce crosstalk.

Due to a magnetic and electrical coupling between two adjacent ones Contact pairs induce a contact pair in adjacent contact pairs a current or influenziert electrical charges, so that it to a Crosstalk comes.

To reduce crosstalk, there are basically several approaches conceivable. Thus, e.g. the individual contact pairs shielded against each other become. A disadvantage of this solution is the increased production costs and the associated costs. Another possibility is the Contact pairs at a great distance to each other to arrange and at the same time To choose distances between the contacts of a couple very small, since the Amounts of field strengths decrease with increasing distance. adversely in such arrangements is that they are very bulky and demands run counter to a compact design. It is also known that compensate for existing crosstalk, but technically very is complex and encounters physical limits.

Another possibility is the arrangement of the contact pairs such that due the field conditions crosstalk is reduced. It was suggested arrange the contact pairs of double lines in such a way that spanned by the contact pairs of a respective double line Surfaces are perpendicular to each other. Becomes certain symmetry conditions due to the field distribution, can be a contact pair on the electrical equipotential surfaces of its adjacent contact pair can be arranged so that the contact pairs electrically and magnetically decoupled are. The contact pairs can be arranged so that cut the areas spanned by the contact pairs. This leads to, that the lines in the connection area to the transmissions interlaced are what causes extra crosstalk. Therefore, be Preferred arrangements in which the spanned surfaces of the contact pairs do not cut. A disadvantage of the known arrangements with it non-cutting surfaces is the large footprint and the changing Connection levels. In principle, similar problems occur due to crosstalk even with multi-core cables.

The invention is therefore based on the problem of an arrangement of contact pairs of double cables and cables of a multi-core cable too create that compact and easily accessible with minimal crosstalk are arranged.

The solution to the problem results from the features of the claims 1 and 4. The arrangement of the contact pairs such that the spanned by them Plane are parallel and the pairs of contacts on electrical equipotential lines their adjacent contact pairs are arranged, is a compact, easily accessible arrangement of the contact pairs to each other possible at the adjacent contact pairs are electrically and magnetically decoupled, so that crosstalk is avoided. The same applies to the multi-core Cable, in which the adjacent pairs of cables on an electrical Equipotential surface of a pair of wires are arranged. Further advantageous Embodiments of the invention will become apparent from the dependent claims.

Due to the formation of the contact pairs, each with the same distance a is a simplified mechanical connection of the double lines to subsequent ones Cable possible. In a further preferred embodiment, all of them are all return conductors arranged in one plane.

Fig. 1

ein Feldbild einer Doppelleitung,

Fig. 2

eine Kontaktanordnung einer zweiten parallelen Doppelleitung im Feldbild der ersten Doppelleitung,

Fig. 3

eine Kontaktanordnung eines 4 x 2-Steckers und

Fig. 4

eine schematische Darstellung zur Berechnung des optimalen Winkels.

The invention is explained in more detail below with reference to a preferred embodiment. The figures show:

Fig. 1

a field picture of a double line,

Fig. 2

a contact arrangement of a second parallel double line in the field image of the first double line,

Fig. 3

a contact arrangement of a 4 x 2 connector and

Fig. 4

a schematic representation for calculating the optimum angle.

wobei in diesem skalaren Vektorprodukt von der magnetischen Feldstärke H nur die zur Fläche F_3,4 senkrechte Komponente einen Beitrag liefert. Das Flächenintegral stellt den magnetischen Fluß dar, der zwischen den beiden Leitern 3, 4 hindurchgeht. Dieser ist gleich Null, wenn die beiden Leiter 3, 4 auf einer gemeinsamen magnetischen Feldlinie H liegen. Durch das elektrische Feld E der Doppelleitung 1, 2 werden auf den Leitern 3, 4 Influenzladungen erzeugt, die über den Lastwiderstand abfließen können und somit ein Übersprechen erzeugen. Das elektrische Feld E der Doppelleitung 1, 2 erzeugt zwischen den beiden Leitern 3, 4 eine Potentialdifferenz von

In Fig. 1, the field image of a double line 1, 2 with the magnetic field lines H and the electric field lines E is shown. The magnetic crosstalk from the first double line 1, 2 to a second double line 3, 4 is directly proportional to the mutual inductance M of this arrangement. The mutual inductance is due to the integration of the magnetic field strength H of the double line 1, 2 over the surface F _3.4 , which is spanned by the line conductors of the double line 3, 4 to

wherein in this scalar vector product of the magnetic field strength H only the component perpendicular to the surface F _3.4 provides a contribution. The area integral represents the magnetic flux passing between the two conductors 3, 4. This is equal to zero, when the two conductors 3, 4 are on a common magnetic field line H. By the electric field E of the double line 1, 2 are generated on the conductors 3, 4 Influenzladungen that can flow through the load resistor and thus generate a crosstalk. The electric field E of the double line 1, 2 generates between the two conductors 3, 4, a potential difference of

This is a line integral on an electric field line E from conductor 3 to conductor 4, the potential difference being zero when the electric field strength E is perpendicular to the surface F _3.4 spanned by the conductors 3, 4. The vectorial electric field E can also be described by the scalar potential, wherein the potential lines are perpendicular to the electric field lines E. In the case of electrical decoupling then the two conductors 3, 4 must be arranged on an equipotential surface of the electrical potential. Since the electric and magnetic field lines E and H are perpendicular to each other, the course of the potential lines is identical to the course of the magnetic field lines H. This in turn means that in Linienleitem an arrangement with magnetic decoupling also has an electrical decoupling. Due to the finite extent of the lines, the electric field E is distorted in the vicinity of the line, since the surface represents an equipotential surface. However, these deviations are negligible at larger distances.

In Fig. 2, the magnetic field H of the double line 1, 2 is shown, wherein the contact spacing of the lines 1, 2 a. 2 shows possible arrangements of the second double line 3, 4, in which the contact spacing is also a. There are therefore an infinite number of possible arrangements of the double lines 3, 4, in which the area F _{3.4 spanned} by the lines 3, 4 is parallel to the surface F _1,2 and the distance of the contact pairs 1, 2 or 3, 4 is the same size, since the double line 3, 4 is located on a magnetic field line H, the two double lines 1, 2 and 3, 4 are both electrically and magnetically decoupled.

FIG. 3 shows a contact arrangement for a 4 × 2 plug. Of the Distance between the lines of each double line 1, 2 or 3, 4 or 5, 6 or 7, 8 is a. In addition, the leads 1, 3, 5, 7 and the return conductors 2 are located, 4, 6, 8 each in a plane, wherein the distance of a return conductor 2, 4, 6 to the adjacent Hinleiter 3, 5, 7 is also a. The resulting Angle α can be calculated using an invoice with the aid of Fig. 4 as calculate follow:

The forward conductor 3 describes in dependence on angle α = 90 ° + β a circle around the return conductor 2 with the radius 2 A = a and the center point shift A. The circle equation for this circle K 1 is: (XA) 2 + Y 2 = (2A) 2 ,

For complete decoupling, the conductors 3, 4 must lie on a magnetic field line which is described by a circle K 2 with the radius R ² = M ² - A ² and the center M: (XM) 2 + Y 2 = M 2 -A 2

The intersection of the two circles K 1, K 2 is obtained by solving the equation system ( X - A ) 2 - ( X - M ) 2 = (2 A ) 2 - M 2 + A 2 ⇒X = 2 · A 2 M - A

From the Fig. 4 takes for the center M = X + A, so that the following relationship results for the X coordinate of the conductor 3: x = 2 * A ,

From the X coordinate of the conductor 3, the angle β can be calculated to:

This results in the desired angle α = β + 90 ° to 101.95 °. sinβ = X - A 2 · A = 2 -1 2 ⇒β = 11.95 °

In the arrangement of FIG. 3, the double lines 5, 6 and 7, 8 are not more exactly on a magnetic field line of the double line 1, 2 so that a Crosstalk is induced. But this crosstalk is due to the large Distance very low. According to the same principle of FIG. 3 can be a multi-core cable e.g. build as a ribbon cable. where the neighboring Line pairs on an electrical equipotential line of a line pair are arranged.

LIST OF REFERENCE NUMBERS

Claims (4)

1. Arrangement of contact pairs of twin conductors for the purpose of reducing crosstalk, characterized in that the contact pairs of the twin conductor (1, 2; 3, 4; 5, 6; 7, 8) define mutually parallel, non-congruent areas (F_1,2; F_3,4; F_5,6; F_7,8), and the twin conductors (1, 2; 3, 4; 5, 6; 7, 8) are arranged on electric equipotential lines of their neighbouring twin conductors (1, 2; 3, 4; 5, 6; 7, 8).
2. Arrangement according to Claim 1, characterized in that the contact pairs of the twin conductors (1, 2; 3, 4; 5, 6; 7, 8) have the same spacing a in each case.
3. Arrangement according to Claim 2, characterized in that all the forward conductors (1, 3, 5, 7) and all the return conductors (2, 4, 6, 8) of the arrangement are arranged in one plane in each case.
4. Multi-core cable having a multiplicity of conductors, characterized in that the conductor pairs define mutually parallel, non-congruent areas, and the conductor pairs are arranged on electric equipotential surfaces of their neighbouring conductor pairs.

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