Cable For High Speed Data Communications

• US 20110290524A1
• Filed: 05/25/2010
• Published: 12/01/2011
• Est. Priority Date: 05/25/2010
• Status: Active Grant

• Current Assignee: Lenovo International Limited (Lenovo Group Ltd.)
• Original Assignee: International Business Machines Corporation
• Inventors: PHAM, NAM H., LINGAMBUDI, ANIL B., SETHURAMAN, SARAVANAN, MUTNURY, BHYRAV M.
• Granted Patent: US 8,552,291 B2
• Time in Patent Office: Days
• US Class Current: 174/102.R
• CPC Class Codes: H01B 11/183 Co-axial cables with at least one helicoidally wound tape-conductor
• CPC Class Codes: H01B 11/203 forming a flat arrangement
• CPC Class Codes: Y10T 29/49117 Conductor or circuit manufacturing

Abstract

A cable for high speed data communications that includes a first inner conductor enclosed by a first dielectric layer and a second inner conductor enclosed by a second dielectric layer, the inner conductors and the dielectric layers disposed within the cable in parallel with a longitudinal axis of the cable; drain conductors disposed within the cable laterally to the inner conductors adjacent to the dielectric layers along the longitudinal axis of the cable and within thirty degrees of a horizontal axis through the inner conductors; and a conductive shield composed of a strip of conductive shield material wrapped in a rotational direction along and about the longitudinal axis around the inner conductors, the dielectric layers, and the drain conductors, including overlapped wraps of the conductive shield material along the longitudinal axis.

Claims

1. A cable for high speed data communications, the cable comprising:

a first inner conductor enclosed by a first dielectric layer and a second inner conductor enclosed by a second dielectric layer, the inner conductors and the dielectric layers disposed within the cable in parallel with a longitudinal axis of the cable;

drain conductors disposed within the cable laterally to the inner conductors adjacent to the dielectric layers along the longitudinal axis of the cable and within thirty degrees of a horizontal axis through the inner conductors; and

a conductive shield comprising a strip of conductive shield material wrapped in a rotational direction along and about the longitudinal axis around the inner conductors, the dielectric layers, and the drain conductors, including overlapped wraps of the conductive shield material along the longitudinal axis.

2. The cable of claim 1 further comprising:

a third inner conductor enclosed by a third dielectric layer and a fourth inner conductor enclosed by a fourth dielectric layer, the third and fourth inner conductors and the third and fourth dielectric layers stacked upon the first and second inner conductors and the first and second dielectric layers parallel with and along the longitudinal axis of the cable; and

drain conductors disposed within the cable laterally to the third and fourth inner conductors adjacent to the third and fourth dielectric layers along the longitudinal axis of the cable and within thirty degrees of a horizontal axis through the third and fourth inner conductors;

wherein the conductive shield material is around all four inner conductors, all four dielectric layers, and all of the drain conductors.

3. The cable of claim 1 further comprising:

a third inner conductor enclosed by a third dielectric layer and a fourth inner conductor enclosed by a fourth dielectric layer, the third and fourth inner conductors and the third and fourth dielectric layers stacked upon the first and second inner conductors and the first and second dielectric layers parallel with and along the longitudinal axis of the cable;

drain conductors disposed within the cable laterally to the third and fourth inner conductors adjacent to the third and fourth dielectric layers along the longitudinal axis of the cable and within thirty degrees of a horizontal axis through the third and fourth inner conductors; and

a conductive shield comprising a strip of conductive shield material wrapped in a rotational direction along the longitudinal axis only around the third and fourth inner conductors, the third and fourth the dielectric layers, and the drain conductors adjacent to the third and fourth dielectric layers, including overlapped wraps of the conductive shield material along the longitudinal axis.

4. The cable of claim 1 wherein the drain conductors further comprise the conductive wires disposed on the horizontal axis through the inner conductors.

5. The cable of claim 1 wherein the drain conductors are disposed within angles defined by lines through the centers of the inner conductors and a horizontal axis through the inner conductors, the angles so defined being equal to or less than thirty degrees from the horizontal axis.

6. The cable of claim 1 wherein the overlapped wraps of the conductive shield material create a bandstop filter that attenuates signals at frequencies in a stopband characterized by a center frequency in the range of 5-10 gigahertz.

7. The cable of claim 1 wherein:

the overlapped wraps of the conductive shield material create a bandstop filter that attenuates signals at frequencies in a stopband; and

the drain conductors comprise uniform current return paths that reduce the attenuation of signals having frequencies in the stopband.

8. The cable of claim 1 wherein:

the overlapped wraps of the conductive shield material create a bandstop filter that attenuates signals at frequencies in a stopband; and

the drain conductors provide a uniform characteristic impedance without disruption throughout the entire length of the cable, circumventing an otherwise disruptive effect of the overlapped wraps of the conductive shield material.

9. The cable of claim 1 wherein the cable further comprises a non-conductive layer disposed parallel to the longitudinal axis and enclosing the inner conductors, the dielectric layers, the drain conductors and the conductive shield.

11. The method of claim 8 wherein the drain conductors are further disposed on the horizontal axis through the inner conductors.

12. The method of claim 8 wherein the drain conductors are further disposed within angles defined by lines through the centers of the inner conductors and a horizontal axis through the inner conductors, the angles so defined being equal to or less than thirty degrees from the horizontal axis.

13. The method of claim 8 wherein the overlapped wraps of the conductive shield material create a bandstop filter that attenuates signals at frequencies in a stopband characterized by a center frequency in the range of 5-10 gigahertz.

14. The method of claim 8 wherein:

the overlapped wraps of the conductive shield material create a bandstop filter that attenuates signals at frequencies in a stopband; and

the drain conductors provide a uniform characteristic impedance without disruption throughout the entire length of the cable, circumventing an otherwise disruptive effect of the overlapped wraps of the conductive shield material.

15. The method of claim 8 further comprising fabricating a non-conductive layer disposed parallel to the longitudinal axis and enclosing the inner conductors, the dielectric layers, the drain conductors, and the conductive shield.

17. The method of claim 15 wherein the drain conductors further comprise the conductive wires disposed on the horizontal axis through the inner conductors.

18. The method of claim 15 wherein the drain conductors further comprise the conductive wires disposed within angles defined by lines through the centers of the inner conductors and a horizontal axis through the inner conductors, the angles so defined being equal to or less than thirty degrees from the horizontal axis.

19. The method of claim 15 wherein the overlapped wraps of the conductive shield material create a bandstop filter that attenuates signals at frequencies in a stopband characterized by a center frequency in the range of 5-10 gigahertz.

20. The method of claim 15 wherein the drain conductors comprise uniform current return paths that reduce the attenuation of signals having frequencies in the stopband.

10. A method of manufacturing a cable for high speed data communications, the cable comprising:

aligning in parallel with a longitudinal axis of the cable and placing adjacent to one another a first inner conductor enclosed by a first dielectric layer and a second inner conductor enclosed by a second dielectric layer;

placing drain conductors in the cable, the drain conductors disposed within the cable laterally to the inner conductors adjacent to the dielectric layers along the longitudinal axis of the cable and within thirty degrees of a horizontal axis through the inner conductors; and

fabricating a conductive shield on the cable by wrapping a strip of conductive shield material in a rotational direction along the longitudinal axis around the inner conductors, the dielectric layers, and the drain conductors, the conductive shield including overlapped wraps of the conductive shield material along and about the longitudinal axis.

16. A method of operation for a cable for high speed data communications, the cable comprising:

a first inner conductor enclosed by a first dielectric layer and a second inner conductor enclosed by a second dielectric layer, the inner conductors and the dielectric layers disposed within the cable in parallel with a longitudinal axis of the cable;

drain conductors disposed within the cable laterally to the inner conductors adjacent to the dielectric layers along the longitudinal axis of the cable and within thirty degrees of a horizontal axis through the inner conductors; and

a conductive shield comprising a strip of conductive shield material wrapped in a rotational direction along and about the longitudinal axis around the inner conductors, the dielectric layers, and the drain conductors, including overlapped wraps of the conductive shield material along the longitudinal axis that create a bandstop filter that attenuates signals at frequencies in a stopband;

the method comprising;

transmitting through the inner conductors a balanced, alternating current signal having a frequency in the stopband, with a return signal path through the conductive shield and the drain conductors;

attenuating the signal by the bandstop filter; and

reducing the attenuation of the signal by the signal return path through the drain conductors.