WO2022208264A1

WO2022208264A1 - Transmission cable

Info

Publication number: WO2022208264A1
Application number: PCT/IB2022/052770
Authority: WO
Inventors: John T. Cowher; Alexander W. Barr; Jr. James G. Vana; Steven D. Solomonson; Richard Yufeng Liu; Catherine A. Leatherdale
Original assignee: 3M Innovative Properties Company
Priority date: 2021-03-31
Filing date: 2022-03-25
Publication date: 2022-10-06

Abstract

A cable assembly is disclosed. The cable assembly includes an electrically conductive wire and a dielectric layer at least partially circumscribing the wire, the dielectric layer defining an internal cavity and the wire being disposed within the internal cavity. A shield layer is disposed at an opposed side of the dielectric layer than is the wire. A plurality of projections are formed on the dielectric layer, the projections extend outwardly toward the shield layer, and a length of a first projection along a corresponding first projection axis is greater than a length of a second projection along a corresponding second projection axis.

Description

TRANSMISSION CABLE

Background

Servers in data centers have ever-increasing data rates. Improved cables and connectors offer superior electrical performance over current connector assemblies.

Summary

In some aspects of the present disclosure, a cable assembly is disclosed. The cable assembly can include an electrically conductive wire and a dielectric layer at least partially circumscribing the wire. The dielectric layer can define an internal cavity and the wire can be disposed within the internal cavity. A shield layer can be disposed at an opposed side of the dielectric layer than is the wire and a plurality of projections can be formed on the dielectric layer. The projections can extend outwardly toward the shield layer, and a length of a first projection along a corresponding first projection axis can be greater than a length of a second projection along a corresponding second projection axis.

In some aspects of the present disclosure, a cable assembly is disclosed. The cable assembly can include an electrically conductive wire and a dielectric layer at least partially circumscribing the wire. The dielectric layer can define an internal cavity and the wire can be disposed within the internal cavity. A shield layer can be disposed at an opposed side of the dielectric layer than is the wire and a projection can be formed on the dielectric layer. The projection can extend outwardly toward the shield layer, and a width of the projection at a projection base can be at least equal to a width of the projection at a projection distal end.

In some aspects of the present disclosure, a cable assembly is disclosed. The cable assembly can include two electrically conductive wires and a dielectric layer at least partially circumscribing the wires. The dielectric layer can define an internal cavity and each wire can be disposed within the internal cavity. A shield layer can be disposed at an opposed side of the dielectric layer than are the wires and at least one projection can be formed on the dielectric layer. The at least one projection can extend outwardly toward the shield layer. Brief Description of the Drawings

FIG. 1 is an upper cross-sectional perspective view of a cable assembly according to exemplary embodiments of the present disclosure.

FIG. 2. is an upper cross-sectional perspective view of a cable assembly, different from that shown in FIG. 1, according to exemplary embodiments of the present disclosure.

FIG. 3 is an upper perspective view of a dielectric layer according to exemplary embodiments of the present disclosure.

FIG. 4 is an upper perspective view of a dielectric layer, different from that shown in FIG. 3, according to exemplary embodiments of the present disclosure.

FIG. 5 is a cross-sectional view of a cable assembly according to exemplary embodiments of the present disclosure.

FIG. 6. is a cross-sectional view of a cable assembly, different from that shown in FIG. 5, according to exemplary embodiments of the present disclosure.

FIG. 7 is an upper perspective view of a dielectric layer according to exemplary embodiments of the present disclosure.

Detailed Description

In the following description, reference is made to the accompanying drawings that form a part hereof and in which various embodiments are shown by way of illustration.

The drawings are not necessarily to scale. It is to be understood that other embodiments are contemplated and may be made without departing from the scope or spirit of the present description. The following detailed description, therefore, is not to be taken in a limiting sense.

All scientific and technical terms used herein have meanings commonly used in the art unless otherwise specified. The definitions provided herein are to facilitate understanding of certain terms used frequently herein and are not meant to limit the scope of the present disclosure. Unless otherwise indicated, all numbers expressing feature sizes, amounts, and physical properties used in the specification and claims are to be understood as being modified in all instances by the term “about.” Accordingly, unless indicated to the contrary, the numerical parameters set forth in the foregoing specification and attached claims are approximations that can vary depending upon the desired properties sought to be obtained by those skilled in the art utilizing the teachings disclosed herein.

As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” encompass embodiments having plural referents, unless the content clearly dictates otherwise. As used in this specification and the appended claims, the term “or” is generally employed in its sense including “and/or” unless the content clearly dictates otherwise.

Spatially related terms, including but not limited to, “lower,” “upper,” “beneath,” “below,” “above,” and “on top,” if used herein, are utilized for ease of description to describe spatial relationships of an element(s) to another. Such spatially related terms encompass different orientations of the device in use or operation in addition to the particular orientations depicted in the figures and described herein. For example, if an object depicted in the figures is turned over or flipped over, portions previously described as below or beneath other elements would then be above those other elements.

As used herein, when an element, component or layer for example is described as forming a “coincident interface” with, or being “on” “connected to,” “coupled with” or “in contact with” another element, component or layer, it can be directly on, directly connected to, directly coupled with, in direct contact with, or intervening elements, components or layers may be on, connected, coupled or in contact with the particular element, component or layer, for example. When an element, component or layer for example is referred to as being “directly on,” “directly connected to,” “directly coupled with,” or “directly in contact with” another element, there are no intervening elements, components or layers for example.

As used herein, “have”, “having”, “include”, “including”, “comprise”, “comprising” or the like are used in their open-ended sense, and generally mean “including, but not limited to.” It will be understood that the terms “consisting of’ and “consisting essentially of’ are subsumed in the term “comprising,” and the like.

Electrical cables are used in many applications. As communications protocols in data centers extend to ever-greater signal speeds, the ability of cable assemblies to span the reach between elements in data centers becomes increasingly difficult with conventional cables. Improved solutions, such as those disclosed herein, can provide the needed reach while still enabling the use of industry-standard connectors such as QSFP, QSFP-DD, and OSFP. Generally, larger gauge wire and lower loss dielectrics are both desirable in a cable to reduce losses and send intelligible data across required distances at high speeds, such as 100 Gb/s. Such features are enabled by the present disclosure

The introduction of air within a cable assembly provides a dual benefit to cable performance. First, the included air reduces the effective dielectric constant and loss tangent for the cable dielectric, which directly reduces dielectric losses in the cable. Second, the included air also reduces a required distance between a cable shield and the wires while maintaining characteristic impedance. Thus, with the same wire gauge, a smaller cable can be constructed with similar or improved conductor losses over a solid dielectric cable. Similarly, disclosed embodiments also enable an increased wire gauge than would otherwise be possible with a conventional cable of the same size, thus enabling lower conductor losses.

Foaming dielectrics is a well-established technology for introducing air into cable dielectrics. However, several drawbacks exist with foamed dielectric cable constructions. First, these cables typically cannot be bent tightly without the foam collapsing and creating a large impedance discontinuity in the cable. Second, controlling the inclusion of air into the dielectrics of these cables such that the resulting foam exhibits a uniform dielectric constant can be challenging. Embodiments and technologies of the present disclosure provide a structured cable construction that introduces air and low-dielectric elements for effective dielectric loss minimization, and enables the use of larger wire gauges in a same sized cable while providing the precision needed to avoid mode conversion losses.

Turning to the figures, FIG. 1 is an upper cross-sectional perspective view of a cable assembly and FIG. 2. is an upper cross-sectional perspective view of a cable assembly, different from that shown in FIG. 1, according to exemplary embodiments of the present disclosure. FIGS. 1 and 2 generally show a cable assembly 100 and various cross-sections thereof. As can be seen in the figures, an X axis can be orthogonal to a Y axis, and each of the X axis and the Y axis can be orthogonal to a Z axis. For clarity, moving upwardly along the Z axis can indicate moving upward vertically in FIG. 1, while moving downwardly along the Z axis can indicate the opposite direction. Moving from the upper right to the lower left along the cable assembly in FIG. 1 can indicate moving forwardly along the X axis, whereas moving in the opposite direction can indicate moving rearwardly along the X axis. Finally, moving towards the right in FIG. 1 can indicate moving forwardly along the Y axis, whereas moving in the opposite direction can indicate moving rearwardly along the Y axis.

FIG. 1 illustrates an exemplary cable assembly (or a transmission cable) 100, along with some features of the cable assembly 100 including wires (or cables) 110, drain wires 190, an interior cavity 125, a dielectric layer 130, a projection 134, an air pocket or air gap 150, and a land or trough 146. FIG. 2 also illustrates an exemplary cable assembly 100 embodiment, having multiple interior cavities 125a, 125b and a wire 110 disposed in each interior cavity 125a, 125b. As can be understood by one skilled in the art, the cable assembly 100 can extend along the X axis, or any other axis, for any length and can include curves, folds, bends, or any other suitable modification. Additionally, the cable assembly 100 can be of any cross-sectional shape or size and can include connectors of any type at any point along the cable assembly 100.

FIG. 3 is an upper perspective view of an exemplary dielectric layer 130 and FIG.

4 is an upper perspective view of another exemplary dielectric layer 130, different from that shown in FIG. 1, according to exemplary embodiments of the present disclosure. As can be seen in FIG. 3, the dielectric layer 130 can include a plurality of projections 134a, 134b, 134c, 134d, 134e, 134f, 134g, 134h, 134i, 134j, 134k, 1341 extending from a base portion 132 of the dielectric layer 130. In some embodiments, one or more of the projections 134a-l 341 can be parallel, substantially parallel, parallel with the X axis and/or substantially parallel with the X axis. As can be seen, heights (as measured along the Z axis) of at least two of the projections 134a-l 341 are equal or are substantially equal. In some embodiments, heights (as measured along the Z axis) of each of the projections 134a-1341 are equal or are substantially equal. In various embodiments, at least two or all of the projections 134a-1341 are equally spaced, or are substantially equally spaced, as measured along the Y axis.

Turning to FIG. 4, another embodiment of a dielectric layer 130 is shown. Similar to the embodiment shown in FIG. 3, the dielectric layer 130 can include a plurality of projections 134a, 134b, 134c, 134d, 134e, 134f, 134g, 134h, 134i, 134j, 134k extending from a base portion 132 of the dielectric layer 130. In some embodiments, one or more of the projections 134a- 134k can be parallel, substantially parallel, parallel with the X axis and/or substantially parallel with the X axis. In various embodiments, at least two or all of the projections 134a- 134k are equally spaced, or are substantially equally spaced, as measured along the Y axis. As can be seen, heights (as measured along the Z axis) of at least two of the projections 134a- 134k are different. In some embodiments, a height (as measured along the Z axis) of a given projection 134a- 134k is different from that of one or more adjacent projections 134a- 134k. In some embodiments, heights (as measured along the Z axis) of projections across some of all of the dielectric layer 130 along the Y axis can increase, decrease, increase linearly, decrease linearly, increase non-linearly, decrease non-linearly, alternate between relatively large heights and relatively low heights, increase then decrease, decrease then increase, increase then decrease in an arcuate fashion, increase then decrease in a parabolic fashion and/or form a sinusoidal sequence.

Turning to FIG. 5, a cross-sectional view of a cable assembly 100 according to exemplary embodiments of the present disclosure is shown. Starting from an outer perimeter of the cable assembly 100, a protective layer 180, a shield layer 170, an adhesive layer 160 and drain wires 190 are visible. The protective layer 180 can include a polymer, polyester, polyethylene, Low-Density Polyethylene (LDPE), High-Density Polyethylene (HDPE), polyethylene terephthalate (PET), a thermoplastic, or any other flexible, thermally-insulating and/or electrically-insulating material known to those skilled in the art. The protective layer 180 can provide physical and electrical protection for the cable assembly 100, as well as provide a substrate on which to adhere the shield layer 170. In various embodiments, a thickness of the protective layer 180 can be, be about, be at least, or be at most 0.00005 inches, 0.0001 inches, 0.0005 inches, 0.001 inches or 0.005 inches.

The shield layer 170 can be proximate, adjacent, and/or in contact with the protective layer 180. The shield layer 170 can include a metal, metal alloy, or any other suitable material known to those skilled in the art. In some embodiments, the shield layer 170 can include aluminum or copper. In various embodiments, a thickness of the shield layer 170 can be, be about, be at least, or be at most 0.00005 inches, 0.0001 inches, 0.0003 inches, 0.0005 inches, 0.001 inches or 0.005 inches. Further, an adhesive or fastener (not shown) could be disposed between the shield layer 170 and the protective layer 180 and could join the shield layer 170 and the protective layer 180.

The adhesive layer 160, or hot-melt layer, can be proximate, adjacent, and/or in contact with one or both of the shield layer 170 and the dielectric layer 130. In various embodiments, a thickness of the adhesive layer 160 can be, be about, be at least, or be at most 0.0001 inches, 0.0005 inches, 0.001 inches, 0.005 inches or 0.01 inches. The adhesive layer 160 can include any polymer, plastic, thermoplastic, Low-Density Polyethylene (LDPE), High-Density Polyethylene (HDPE), PET, or another hot melt.

The dielectric layer 130, can be proximate, adjacent, and/or in contact with one or more of the adhesive layer 160, the wire 110, the cable adhesive layer 114 and the interior cavity 125. The dielectric layer 130 can include any polymer, plastic, thermoplastic, Low- Density Polyethylene (LDPE), High-Density Polyethylene (HDPE), PET, or another hot melt. In various embodiments, the dielectric layer 130 (or the material thereof) can define a relative permittivity or dielectric constant of, of about, of at least, or of at most, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.05, 2.1, 2.15, 2.2, 2.25, 2.27, 2.3, 2.32, 2.35, 2.4, 2.45, 2.5, 2.55, 2.6, 2.65, 2.7, 2.8, 2.9 or 3.0. In some embodiments, the dielectric layer 130 (or the material thereof) can define a relative permittivity or dielectric constant between 2.25 and 2.27, or between about 2.25 and about 2.27.

The dielectric layer 130 can define one or more projections 134, 134b- 134f and a base portion 132. The projections 134b-134f can extend outwardly from the base portion 132 towards an exterior of the cable assembly 100. In some embodiments, the projections 134b-134f can extend outwardly from the wire 110, cable adhesive layer 114, interior cavity 125, 125a, 125b, base portion 132, and/or from a geometric center 127 of the cable assembly 100, and further can extend towards one or more of the adhesive layer 160, shield layer 170, protective layer 180, drain wire 190, and an exterior of the cable assembly 100. One or more of the projections 134b-134f (as can also be seen in FIGS. 3 and 4) can be formed in parallel with one another and can be formed along a longitudinal direction of the cable assembly 100, or the X axis. The projections 134b- 134f can be machined, molded, micro-replicated, extruded, or formed through any suitable process known to those skilled in the art. Although projections 134b-134f are shown in FIGS. 5 and 6, it is to be understood that any descriptions or features of any one or more projections 134, 134a-1341 in this disclosure can apply to any projection 134, 134a-1341 in any figure or description thereof, whether specifically labeled or not. As can be seen, a distal end 142 of each projection 134b- 134f can contact, be proximate and/or be adjacent the adhesive layer 160. A land 146, or a trough or an intermediate portion, can be formed on the base portion 132 between projections 134, 134b-134f. Additionally, a pocket 150 can be formed between the dielectric layer 130 and the adhesive layer 160. Specifically, the pocket 150 can be formed between, adjacent and/or in contact with one or more of the dielectric layer 130, base portion 132, land 146, projection 134, 134a-1341, adhesive layer 160 and shield layer 170. The pockets 150 can be filled with air, a gas, a fluid, a solid, a liquid, or any other suitable material having a low dielectric constant. In some embodiments, at least one pocket 150 is disposed between the dielectric layer 130 or base portion 132 and one or more of the shield layer 170 and the adhesive layer 160. In some embodiments, the dielectric layer 130 and/or projections 134, 134b-134f directly contact the shield layer 170.

The wire 110 can be wholly or partially surrounded by a cable adhesive layer 114. The cable adhesive layer 114 can include Low-Density Polyethylene (LDPE), High- Density Polyethylene (HDPE), PET, or any other adhesive or thermoplastic. In some embodiments, the cable adhesive layer 114 includes the same material as the dielectric layer 130. The cable adhesive layer 114 can serve to protect and/or insulate the wire 110, and further can keep the wire 110 in place relative to the adhesive layer 160, shield layer 170, another wire 110, and/or the cable assembly 100. In some embodiments, the wire 110 directly contacts the dielectric layer 130.

The wire 110 can be an electrical conductor and can include a metal, metal alloy, plurality of materials including a metal, or any other suitable conducting material known to those skilled in the art. The wire 110 can be of any suitable gauge, and in some embodiments can be 24AWG. In various embodiments, the wire 110 can include copper, silver, tin, aluminum, steel, or gold. In various embodiments, the cable 100 can include a first conductive material or metal (such as copper) and can be plated with another conductive material or metal (such as gold, silver, aluminum, or tin).

One or more drain wires 190 can be included with the cable assembly 100. The drain wire 190 can include any conductive material, metal, or metal alloy. In various embodiments, the drain wire 190 can include copper, silver, tin, aluminum, steel, or gold. The drain wire 190 can work in concert with the shield layer 170 to enable effective grounding and carry undesirable electrical noise to ground away from elements of the cable assembly 100. In some embodiments, the shield layer 170 can be in direct electrical contact with, in physical contact with, or proximate the drain wire 190 such that electrical current can flow from the shield layer 170 to the drain wire 190, which can occur via induction (AC coupling). The drain wire 190 can be of any gauge, and in some embodiments is 30AWG.

In various embodiments, the cable assembly 100, wire 110, dielectric layer 130, drain wire 190 and/or shield layer 170 can exhibit a continuous, constant, or substantially constant down-web cross-section, which can be defined as being parallel to the X axis.

The interior cavity 125 can be formed within various elements of the cable assembly 100 In particular, the interior cavity 125 can be formed within the adhesive layer 160, shield layer 170, dielectric layer 130, and/or protective layer 180. The wires 110 and cable adhesive layer 114 can be disposed within, or substantially within, the interior cavity 125. The interior cavity 125 can be (wholly or partially) hollow, filled with air, or filled with any fluid, gas, liquid, or solid. In some embodiments, the one or more wires 110 can be the same size as the interior cavity 125, 125a, 125b, while in other embodiments, the one or more wires 110 are smaller than the interior cavity 125, 125a, 125b. In some embodiments, the volume fraction of air within the adhesive layer 160 and/or shield layer 170 is, is about, is at least, or is at most 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65% or 70%.

A geometric center 127 of a cross-section (taken perpendicular to the X axis) of the cable assembly 100 can also be defined. The geometric center 127 can be located within the interior cavity 125, or within the dielectric layer 130 as can be seen in FIG. 6. In some embodiments, the geometric center 127 can be located at a middle point of the cable assembly 100 as measured along one or both of the Y axis and the Z axis.

In various embodiments, the projections 134, 134a-l 341 can protrude outwardly along a projection axis 144. It is to be understood that a projection axis 144, 144a, 144b, 144c, 144d, 144e, 144f, 144g, 144h, 144i, 144j, 144k, 1441 can correspond to a given projection 134, 134a- 1341. A projection axis 144, 144a-1441 can extend through the wire 110 and/or the geometric center 127. Further, two or more projection axes 144, 144a-1441 can be parallel or non-parallel, and two or more adjacent projection axes 144, 144a-1441 can be parallel or non-parallel. In some embodiments, one or more projection axes 144, 144a-1441 can be entirely disposed within a corresponding projection 134, 134a-1341 when viewed cross-sectionally down the X axis (as exemplarily shown in FIGS. 5 and 6). In some embodiments, one or more projection axes 144, 144a-1441 can pass through one or both of a base portion 138, 138a-1381 and a distal end portion 142, 142a-1421 of a corresponding projection 134, 134a-1341 when viewed cross-sectionally down the X axis (as exemplarily shown in FIGS. 5 and 6).

In certain embodiments, a length of a given projection 134, 134b- 134f can be measured between, or along a respective projection axis 144, 144b- 144f between, the base portion 132 or projection base 138, 138b-138f and the adhesive layer 160, the shield layer 170 or the distal end 142, 142b-142f.

In various embodiments, at least two or all of the projections 134b-134f are equally spaced, or are substantially equally spaced, as measured along the Y axis. As can be seen, lengths of at least two of the projections 134b- 134f can be different. In some embodiments, a length of a given projection 134b-134f is different from that of one or more adjacent projections 134b-134f. In various embodiments, lengths of projections 134b-134f moving from one side of the cable assembly 100 to the other across the Y axis, increase, decrease, increase linearly, decrease linearly, increase non-linearly, decrease non-linearly, alternate between relatively large heights and relatively low heights, increase then decrease, decrease then increase, increase then decrease in an arcuate fashion, increase then decrease in a parabolic fashion and/or form a sinusoidal sequence.

Additionally, the wires 110 and/or the drain wires 190 can be solid or stranded, and can have any cross-sectional shape (taken perpendicular to the X axis) such as circles, squares, triangles, ovals, rectangles, pentagons, hexagons, heptagons, octagons, organic shapes, partially-organic shapes, parallelograms, polygons and non-polygonal organic shapes.

In various embodiments, heights of projections 134, 134b-134f, as measured along a projection axis 144, 144b -144f between a projection base 138, 138b-138f and a distal end 142, 142b-142f can be, can be about, can be at most, or can be at least 0.7 0.8, 0.9,

1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.1, 2.2, 2.3, 2.4 or 2.5 times a diameter of a wire 110 or of a greatest width of a wire 110 taken perpendicularly to the X axis.

FIG. 6. is a cross-sectional view of a cable assembly 100, different from that shown in FIG. 5, according to exemplary embodiments of the present disclosure. The embodiment of FIG. 6 is similar to that shown in FIG. 5, however the dielectric layer 130 is joined towards the center of the cable assembly 100. This effectively forms two interior cavities 125a, 125b, each including one wire 110. Additionally, a geometric center 127 of the cable assembly 100 is now defined within the dielectric layer 130. Further, the joining of the dielectric layer 130 also alters the directions and lengths (and other properties) of some of the projections 134, such as 134e and 134f. Other properties and characteristics of the embodiment of FIG. 5 are generally shared with the embodiment shown in FIG. 6.

FIG. 7 is an upper perspective view of a portion of a dielectric layer 130 according to exemplary embodiments of the present disclosure. Projections 134b, 134c, 134d can be seen in the figure extending upwardly along the Z axis from the base portion 132. WB indicates the width (as measured along the Y axis) of the projection base 138c and WDE indicates the width (as measured along the Y axis) of the projection distal end 142c. The projection axis 144c can be perpendicular to, or substantially perpendicular to, the Y axis. In some embodiments, WB is greater than WDE. In some embodiments WB is equal to, or substantially equal to, WDE. In some embodiments, WB is greater than or equal to WDE. In some embodiments, the projection axis 144c is perpendicular, or substantially perpendicular, to the projection base 138c, or to an axis along which WB is measured. In some embodiments, the projection axis 144c is perpendicular, or substantially perpendicular, to the projection distal end 142c, or to an axis along which WDE is measured. In various embodiments, the projection distal end 142c is parallel to, or substantially parallel to, the projection base 138c. In various embodiments, a ratio of WB/WDE for one or more projections 134, 134a-1341 can be, can be about, can be at most, or can be at least 0.70.8, 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, 3.0, 3.1, 3.2, 3.3, 3.4, or 3.5.

In some embodiments, one or more of the cable assembly 100, cable adhesive layer 114, dielectric layer 130, adhesive layer 160, shield layer 170, protective layer 180, or drain wire 190, or any constituent element thereof, can be cast, molded, extruded, micro- replicated, machined or otherwise formed as a single, integral component. In some embodiments, one or more of the cable assembly 100, cable adhesive layer 114, dielectric layer 130, adhesive layer 160, shield layer 170, protective layer 180, or drain wire 190 can be formed of or can include a metal, metal alloy, polymer, LDPE, HDPE, PET, composite material, ceramic, organic material, electrically-conductive material, electrical insulator, or any other material known to those skilled in the art. Additional details of transmission cables including air pockets and dielectric layers are disclosed in WO 2012/138729, which is incorporated herein by reference for all that it contains.

The disclosed embodiments provide numerous benefits and mechanisms for the efficient, effective, and stable operation of a cable assembly 100. The present disclosure provides a novel structured cable construction that introduces and structures air content for effective dielectric loss minimization and enables a larger wire gauge in the same size cable assembly. The disclosed embodiments further provide the precision needed in the cable assembly to avoid generating appreciable mode conversion losses in the cable and their accompanying drawbacks. These features are important in advanced data centers where the band rate can be 26.56 GHz or 28 GHz or higher.

The terms and expressions that have been employed are used as terms of description and not of limitation, and there is no intention in the use of such terms and expressions of excluding any equivalents of the features shown and described or portions thereof, but it is recognized that various modifications are possible within the scope of the embodiments of the present disclosure. Thus, it should be understood that although the present disclosure has been specifically disclosed by specific embodiments and optional features, modification and variation of the concepts herein disclosed may be resorted to by those of ordinary skill in the art, and that such modifications and variations are considered to be within the scope of embodiments of the present disclosure. The complete disclosures of the patents, patent documents, and publications cited herein are incorporated by reference in their entirety as if each were individually incorporated. To the extent that there is any conflict or discrepancy between this specification as written and the disclosure in any document that is incorporated by reference herein, this specification as written will control.

Claims

What is claimed is:

1. A cable assembly, comprising: an electrically conductive wire; a dielectric layer at least partially circumscribing the wire, the dielectric layer defining an internal cavity and the wire being disposed within the internal cavity; a shield layer disposed at an opposed side of the dielectric layer than is the wire; and a plurality of projections formed on the dielectric layer, the projections extending outwardly toward the shield layer, wherein a length of a first projection along a corresponding first projection axis is greater than a length of a second projection along a corresponding second projection axis.

2. The cable assembly of claim 1, wherein two sequential projections have different lengths as measured along their projection axes, and the projection having the longer length is disposed closer to the electrically conductive wire than is the projection having the shorter length.

3. The cable assembly of claim 1, wherein two adjacent projections have different lengths as measured along their projection axes, and the projection having the longer length is disposed closer to a geometric center of the cable assembly than is the projection having the shorter length.

4. The cable assembly of claim 1, wherein lengths of projections along their respective projection axes, when moving from one side of the cable assembly to the other along the Y axis, increase and subsequently decrease.

5. The cable assembly of claim 1, wherein the dielectric layer defines a second internal cavity and a second wire is disposed within the second cavity.

6 The cable assembly of claim 1, wherein the shield includes aluminum.

7. The cable assembly of claim 1, wherein the dielectric layer includes polyethylene.

8. The cable assembly of claim 1, further including an air pocket formed between the dielectric layer and the shield layer.

9. A cable assembly, comprising: an electrically conductive wire; a dielectric layer at least partially circumscribing the wire, the dielectric layer defining an internal cavity and the wire being disposed within the internal cavity; a shield layer disposed at an opposed side of the dielectric layer than is the wire; and a projection formed on the dielectric layer, the projection extending outwardly toward the shield layer, wherein a width of the projection at a projection base is at least equal to a width of the projection at a projection distal end.

10. The cable assembly of claim 9, wherein the shield includes aluminum.

11. The cable assembly of claim 9, wherein the dielectric layer includes a thermoplastic.

12. The cable assembly of claim 9, wherein the dielectric layer includes polyethylene.

13. The cable assembly of claim 9, wherein the dielectric layer defines a dielectric constant below 2.5.

14. The cable assembly of claim 9, further including an air pocket between the dielectric layer and the shield layer.

15. A cable assembly, comprising: two electrically conductive wires; a dielectric layer at least partially circumscribing the wires, the dielectric layer defining an internal cavity and each wire being disposed within the internal cavity; a shield layer disposed at an opposed side of the dielectric layer than are the wires; and at least one projection formed on the dielectric layer, the at least one projection extending outwardly toward the shield layer.

16. The cable assembly of claim 15, wherein the shield includes aluminum.

17. The cable assembly of claim 15, wherein the dielectric layer includes a thermoplastic.

18. The cable assembly of claim 15, wherein the dielectric layer includes polyethylene.

19. The cable assembly of claim 15, wherein the dielectric layer defines a dielectric constant below 2.5.

20. The cable assembly of claim 15, further including an air pocket formed between the dielectric layer and the shield layer.