High performance telecommunications cable

1. A separator spline for use in a telecommunications cable, the spline comprising:

a principal dividing strip comprised of a middle strip and first and second outer strips; and

first and second subsidiary dividing strips attached longitudinally along said principal strip and on opposite sides thereof, wherein a point of attachment of said first subsidiary strip is between said middle strip and said first outer strip and a point of attachment of said second subsidiary strip is between said second outer strip and said middle strip.

2. The separator spline of claim 1 , wherein, when the cable is viewed in cross section, said middle strip and said first and second outer strips lie in a first plane, said first subsidiary dividing strip lies in a second plane and said second subsidiary dividing strip lies in a third plane and further wherein said first plane is at an angle to said second and third plane.

3. The separator spline of claim 2 , wherein said second and third planes are substantially at rights angles to said first plane.

4. The separator spline of claim 2 , wherein said second and third plane are in parallel.

5. The separator spline of claim 1 , wherein said first subsidiary strip is thicker than said second subsidiary strip.

6. The separator spline of claim 1 , wherein said principal dividing strip is thicker than said subsidiary strips.

7. A telecommunications cable comprising:

four twisted pairs of conductors; and

a separator spline comprised of a principal dividing strip and a first subsidiary dividing strip attached longitudinally along a first side of said principal dividing strip and a second dividing strip attached longitudinally along a second side of said principal dividing strip, said spline separating said four twisted pairs such that they are arranged in a staggered configuration.

8. The cable of claim 7 , wherein said principal strip comprises a middle strip and first and second outer strips and wherein a point of attachment of said first subsidiary strip is between said middle strip and said first outer strip and a point of attachment of said second subsidiary strip is between said second outer strip and said middle strip.

9. A telecommunications cable comprising:

a plurality of twisted pairs of conductors arranged around and running along an axis; and

a cable jacket surrounding said twisted pairs, said jacket comprising an outer surface wherein said outer surface defines a tube having a helical centre path arranged around and running along said axis;

wherein said twisted pairs are arranged helically around said axis and said helical centre path twists helically around said axis in a direction opposite to that of said twisted pairs.

10. The cable of claim 9 , further comprising an elongate filler element wound around said twisted pairs underneath said cable jacket.

11. The cable of claim 9 , wherein a pitch of said helical centre path along said axis is random.

12. The cable of claim 9 , wherein said cable jacket further comprises a protrusion arranged around and running along said outer surface of said jacket and wherein said protrusion is arranged helically around said axis.

13. A telecommunications cable comprising;

a first set of twisted pairs of conductors arranged on opposite sides and running along an axis;

a second set of two twisted pairs of conductors arranged on opposite sides and running along said axis; and

a spline separating each of said twisted pairs;

wherein a first flat surface bounded by said first set and a second flat surface bounded by said second set intersect along said axis at an oblique angle.

14. The cable of claim 13 , wherein said spline comprises a principal dividing strip, a first subsidiary dividing strip attached longitudinally along a first side of said principal dividing strip and a second dividing strip attached longitudinally along a second side of said principal dividing strip.

15. The cable of claim 14 , wherein said principal strip comprises a middle strip and first and second outer strips and wherein a point of attachment of said first subsidiary strip is between said middle strip and said first outer strip and a point of attachment of said second subsidiary strip is between said second outer strip and said middle strip.

16. A telecommunications cable comprising;

a first set of two twisted pairs of conductors arranged on opposite sides and running along an axis and separated by a first distance;

a second set of two twisted pairs of conductors on opposite sides of and running along said axis and separated by a second distance less than said first distance; and

a spline separating each of said twisted pairs;

wherein each of said first set of twisted pairs has a twist lay which is shorter than a twist lay of either of said second set of twisted pairs.

17. A telecommunications cable comprising:

a plurality of twisted pairs of conductors;

an elongate filler element wound helically around said twisted pairs along a length of the cable; and

a cable jacket covering said element and said twisted pairs;

wherein said plurality of twisted pairs are wound helically along the length of the cable and wherein a direction of rotation of said element is opposite to that of said twisted pairs.

18. The cable of claim 17 , wherein a pitch of said element along the cable varies randomly.

19. The cable of claim 17 , wherein a thickness of said element varies along its length.

20. The cable of claim 17 , wherein said element is a rod.

21. The cable of claim 17 , wherein said element is hollow.

22. The cable of claim 17 , wherein said element comprises a conductor.

23. The cable of claim 17 , further comprising a spline separating said twisted pairs.

24. A telecommunications cable comprising;

a first set of two parallel twisted pairs of conductors arranged on opposite sides of and wound helically around a first elongate path;

a second set of two parallel twisted pairs of conductors arranged on opposite sides of and wound helically around a second elongate path; and

a spline separating each of said twisted pairs;

wherein said helically wound first set has a radius greater than said helically wound second set.

25. The cable of claim 24 , further comprising a cable jacket and an elongate filler element wound around said twisted pairs underneath said jacket.

26. The cable of claim 25 , where said element is wound in a direction opposite to that of said first set of twisted pairs.

27. The cable of claim 24 , wherein each of said second set of twisted pairs has a twist lay which is longer than a twist lay of either of said first set of twisted pairs.

28. A telecommunications cable comprising:

a plurality of parallel pairs of conductors arranged helically along an axis;

a cable jacket, said jacket when viewed in transverse cross section comprising an oblong part surrounding said helical parallel pairs and a protruding part extending from an outer surface of the jacket;

wherein said oblong part rotates along said axis and said protruding part winds about said axis and further wherein a pitch of said winding protruding part is variable versus said rotation of said oblong part.

29. The cable of claim 28 , further comprising a spline separating said helical pairs, said spline having an elongate cross section.

30. The cable of claim 28 , wherein said variable pitch is random.

31. The cable of claim 28 , wherein a direction of rotation of said oblong part is opposite to a direction of rotation of said winding protruding part.

32. The cable of claim 28 , further comprising a filler element wound helically about said helical pairs, said element comprising a direction of rotation which is opposite to a direction of rotation of said helical pairs.

33. A method for fabricating a telecommunications cable comprising the steps of:

providing four twisted pairs of conductors; and

placing a separator spline between said twisted pairs, said spline comprising a principal dividing strip and a first subsidiary dividing strip attached longitudinally along a first side of said principal dividing strip and a second dividing strip attached longitudinally along a second side of said principal dividing strip, said spline separating said four twisted pairs such that they are arranged asymmetrically.

34. A method for reducing cross talk between adjacent cables in a telecommunications system, the method comprising the steps of:

for each of the cables:

providing a plurality of twisted pairs of conductors;

winding helically an elongate filler element around said twisted pairs; and

covering said twisted pairs and said element with a cable jacket, said element introducing a visible distortion into an outer surface of said jacket;

wherein said twisted pairs are wound helically around an axis in a first direction and where said helical element has a direction of rotation opposite to that of said helical twisted pairs.

35. The method of claim 34 , wherein said winding step comprises winding said element helically around said twisted pairs.

36. The method of claim 35 , wherein said helical element has a pitch which varies randomly along its length.