Patent Publication Number: US-2015075834-A1

Title: Cable with twisted pairs of insulated conductors

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present application is a continuation-in-part of and claims priority from U.S. patent application Ser. No. 12/688,677 titled “Cable with Twisted Pairs of Insulated Conductors” filed Jan. 15, 2010, the complete subject matter of which is hereby expressly incorporated by reference in its entirety 
    
    
     BACKGROUND OF THE INVENTION 
     The subject matter described and/or illustrated herein relates generally to cables, and more particularly, to cables using at least two twisted pairs of insulated conductors. 
     Some known data communication cables include pairs of insulated conductors that are twisted together, sometimes referred to as “twisted pairs.” When twisted pairs are closely placed, such as in a cable, electrical energy may be transferred between two or more of the twisted pairs, which is commonly referred to as “crosstalk.” As operating frequencies of data communication cables increase, improved crosstalk isolation between the twisted pairs becomes more important. For example, data communication cables must meet electrical performance characteristics required for transmission at frequencies above a predetermined threshold. Standards organizations, such as the International Electrotechnical Commission (IEC), the International Organization of Standardization (ISO), the Telecommunications Industry Association (TIA) and the Electronics Industry Association (EIA), have developed standards which specify specific categories of performance for cable impedance, attenuation, skew, and crosstalk isolation. 
     Various cable designs have been used to attempt to reduce crosstalk and meet industry standards. For example, some known data communication cables include twisted pairs formed with relatively tight twists. Each twisted pair has a specified distance between twists referred to as the “twist lay.” When adjacent twisted pairs have the same twist lay and/or twist direction, they tend to be more closely spaced, which may increase the amount of crosstalk. Accordingly, each twisted pair within the cable may have a unique twist lay to increase the spacing between pairs and thereby attempt to reduce crosstalk. Moreover, the twist direction of the twisted pairs may also be varied in an attempt to reduce crosstalk. However, varying twist lay and/or direction of the twisted pairs may achieve only limited crosstalk isolation. 
     Another attempt at solving the problem of twisted pairs lying too closely together within a cable includes a cable having four twisted pairs radially disposed about a central core. Each twisted pair nests between two separators of the central core such that each twisted pair is separated from adjacent twisted pairs by the central core. The central core preserves the geometry of the twisted pairs relative to each other, which may facilitate reducing and/or stabilizing cross talk between the twisted pairs. However, the central core may achieve only a limited reduction of crosstalk. 
     Accordingly, some of the problems with at least some known data communication cables include an undesirably high amount of crosstalk between twisted pairs. For example, if a cable includes more than four twisted pairs bundled within a common jacket, crosstalk levels may not comply with the transmission requirements of TIA/EIA-568C. 
     BRIEF DESCRIPTION OF THE INVENTION 
     In one embodiment, a cable includes first and second twisted pairs of insulated conductors, a first inner shield at least partially surrounding the first twisted pair. The first inner shield is at least partially conductive. A second inner shield at least partially surrounds the second twisted pair. The second inner shield is at least partially conductive. An at least partially conductive outer shield at least partially surrounds the first and second twisted pairs and the first and second inner shields such that the first and second twisted pairs and the first and second inner shields extend within an internal passageway of the outer shield. 
     In another embodiment, a cable includes an insulative jacket and sub-cables positioned within the jacket such that the jacket at least partially surrounds the sub-cables. At least some of the sub-cables include first and second twisted pairs of insulated conductors. A first inner shield at least partially surrounds the first twisted pair. The first inner shield is at least partially conductive. A second inner shield at least partially surrounds the second twisted pair. The second inner shield is at least partially conductive. An at least partially conductive outer shield at least partially surrounds the first and second twisted pairs and the first and second inner shields such that the first and second twisted pairs and the first and second inner shields extend within an internal passageway of the outer shield. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view illustrating a cross section of a portion of an exemplary embodiment of a cable. 
         FIG. 2  is a perspective view of a portion of an exemplary embodiment of a central core of a sub-cable of the cable shown in  FIG. 1 . 
         FIG. 3  is a cross-sectional view of the central core shown in  FIG. 2 . 
         FIG. 4  is a cross-sectional view of an exemplary embodiment of a sub-cable of the cable shown in  FIG. 1 . 
         FIG. 5  is a cross-sectional view of the cable shown in  FIG. 1 . 
         FIG. 6  is a cross-sectional view of another exemplary embodiment of a cable. 
         FIG. 7  is a cross-sectional view of a portion of the cable shown in  FIG. 6  illustrating an exemplary embodiment of a sub-cable of the cable shown in  FIG. 6 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       FIG. 1  is a perspective view illustrating a cross section of a portion of an exemplary embodiment of a cable  10 . In the description that follows, the cable  10  will be described and/or illustrated in terms of premise cabling, such as, but not limited to, a data communication cable and/or the like. However, it is to be understood that the benefits described and/or illustrated herein are also applicable to other types of cables, including, but not limited to, wires, cords, cables, and/or the like of any type. The following description and illustrations are therefore provided for illustrative purposes only and are but one potential application of the subject matter described and/or illustrated herein. 
     The cable  10  includes an insulative jacket  12  and a plurality of sub-cables  14  positioned within the jacket  12 . A portion of the jacket  12  has been removed from  FIG. 1  to illustrate the sub-cables  14 . Each sub-cable  14  may be referred to herein as a “cable”. As  FIG. 1  illustrates, the jacket  12  at least partially surrounds the sub-cables  14 . Specifically, the jacket  12  includes an internal passageway  16  within which the sub-cables  14  extend. The sub-cables  14  extend within the passageway  16  along the length (only a portion of which is illustrated herein) of the cable  10 . The jacket  12  is fabricated from any insulative, non-conductive materials, such as, but not limited to, polyvinyl chloride (PVC), polypropylene, a polymer, a fluoropolymer, a plastic, polyethylene, and/or the like. In the exemplary embodiment, the jacket  12  includes an approximately smooth inner surface  18  and an approximately smooth outer surface  20 . In alternative embodiments, the inner surface  18  and/or the outer surface  20  may not be approximately smooth. The cable  10  and the jacket  12  extend along a central longitudinal axis  22  that extends along the length of the cable  10 . 
     In the exemplary embodiment, each of the sub-cables  14  includes a central core  24 , a plurality of twisted pairs  26  of insulated conductors  28 , and a conductive shield  30 . The twisted pairs  26  may each be referred to herein as a “first”, a “second”, a “third”, and/or a “fourth” twisted pair. A portion of each of the shields  30  has been removed from  FIG. 1  to illustrate the central core  24  and twisted pairs  26 . As will be described in more detail below, the central core  24  separates the twisted pairs  26  from one another. As described above, in the exemplary embodiment each of the conductors  28  is at least partially surrounded by an insulative layer  32 . The conductors  28  may be fabricated from any conductive materials, such as, but not limited to, copper and/or the like. The insulative layers  32  are fabricated from any insulative, non-conductive materials, such as, but not limited to, PVC, polypropylene, a polymer, a fluoropolymer, a plastic, polyethylene, and/or the like. 
       FIG. 2  is a perspective view of a portion of an exemplary embodiment of a central core  24 .  FIG. 3  is a cross-sectional view of the central core  24 . The central core  24  includes a central hub  36  and a plurality of separators  38  that extend outwardly from the hub  36 . Each of the separators  38  may be referred to herein as a “first”, a “second”, a “third”, and/or a “fourth” separator. The boundaries of the hub  36  are indicated in  FIG. 3  with phantom lines for clarity. The hub  36  extends a length along a central longitudinal axis  40 . The separators  38  extend radially outward from the hub  36  relative to the central longitudinal axis  40 . Each adjacent pair of separators  38  defines a channel  42  therebetween. Each channel  42  is configured to receive a corresponding one of the twisted pairs  26  ( FIGS. 1 ,  4 , and  5 ) therein, as will be described below. 
     In the exemplary embodiment, the central core  24  includes four separators  38  that define four channels  42 , and each channel  42  is positioned in a different quadrant of the central core  24 . But, the central core  24  may include any number of the separators  38  that define any number of channels  42  for holding any number of twisted pairs  26 . Moreover, the channels  42  may be arranged around the central longitudinal axis  40  in any other pattern than shown herein. The exemplary central core  24  shown herein includes a cross shape. Specifically, adjacent separators  38  of the exemplary central core  24  shown herein are angled at approximately 90° relative to each other. However, in addition or alternatively, the central core  24  may include other shapes, which may depend on the number of separators  38 , the relative orientation and/or pattern of the separators  38 , and/or the like. 
     The separators  38  extend outwardly from the hub  36 . Each separator  38  includes an arm segment  50  and an end segment  48  that extends outwardly from the arm segment  50 . The end segments  48  may each be referred to herein as a “first” and/or a “second” end segment. The end segment  48  of each separator  38  includes one or more finger segments  52 . Each finger segment  52  may be referred to herein as a “first” and/or a “second” finger segment. The arm segments  50  extend outwardly from the hub  36 . Each finger segment  52  extends outwardly from the corresponding arm segment  50  to a tip  53 . Specifically, each arm segment  50  extends outwardly from the hub  36  to an end  56 . The finger segments  52  extend from the arm segments  50  at bends  54  that are located at the ends  56  of the arm segments  50 , such that the finger segments  52  extend outwardly from the end  56  of the corresponding arm segment  50 . The finger segments  52  further define the channels  42  of the central core  24 . Specifically, exterior surfaces  58  and  60  of the arm and finger segment  50  and  52 , respectively, define boundaries of the channels  42 . Each channel  42  is thus defined by the space extending between the exterior surfaces  58  and  60  of the corresponding separators  38 . 
     In the exemplary embodiment, each separator  38  includes two finger segments  52  that extend outwardly from the corresponding arm segment  50  in opposite directions. Accordingly, each separator  38  includes a “T” shape, as can be seen in both  FIGS. 1 and 2 . Alternatively, one or more of the separators  38  includes only one finger segment  52 . Moreover, in some alternative embodiments one or more of the separators  38  includes more than two finger segments  52 . In the exemplary embodiment, each finger segment  52  extends outwardly from the corresponding arm segment  50  at an angle of approximately 90°. Specifically, each of the bends  54  is approximately 90°. But, each finger segment  52  may extend from the corresponding arm segment  50  at a bend  54  having any other angle than approximately 90°, such as, but not limited to, an acute or obtuse angle. 
     The central core  24  is optionally fabricated from one or more dielectric materials to facilitate insulating the twisted pairs from each other, such as, but not limited to, PVC, polypropylene, foam polypropylene, a polymer, a fluoropolymer, a plastic, polyethylene, and/or the like. One example of a method of forming the central core  24  with one or more dielectric materials includes extruding or molding. Optionally, the central core  24  may include conductive materials in addition or alternatively to the dielectric materials to provide shielding between the twisted pairs  26 . For example, the central core  24  may be fabricated entirely from one or more conductive materials or may include one or more conductive layers formed on one or more dielectric materials. One example of a conductive central core  24  includes forming the central core  24  using a laminated metal tape. In some embodiments, the central core  24  is relatively flexible, while in other embodiments the central core  24  is relatively rigid. 
     The central core  24  shown in  FIGS. 2 and 3  is an exemplary core that can be used in accordance with one embodiment of the cable and/or sub-cables described and/or illustrated herein. In addition or alternatively, other known cores could be employed with the cable and/or sub-cables described and/or illustrated herein. The central core  24  illustrated herein is a product of Cable Components Group LLC of Framingham, Mass. 
       FIG. 4  is a cross sectional view of an exemplary embodiment of a sub-cable  14 . In the exemplary embodiment, the sub-cable  14  includes the central core  24 , four twisted pairs  26 , and the shield  30 . The shield  30  may be fabricated from any conductive materials, such as, but not limited to, a laminated metal tape, an aluminum polyimide laminated tape, an aluminum biaxially-oriented polyethylene terephthalate (BoPEt) laminated tape, a braid of conductive strands, fibers, and/or the like, a tube formed from a continuous (e.g., a sheet) conductive material, and/or the like. The shield  30  is optionally connected to a ground or other source of electrical energy to provide active shielding. The shield  30  extends around the central core  24  and the twisted pairs  26 . Specifically, the shield  30  includes an internal passageway  62  within which the central core  24  and twisted pairs  26  extend. Each twisted pair  26  extends within a corresponding one of the channels  42  of the central core  24 . Each separator  38  extends between two adjacent twisted pairs  26 . Specifically, the arm segment  50  of each separator  38  extends between adjacent twisted pairs  26  to separate the adjacent twisted pairs  26  along at least a portion of the length of the sub-cable  14 , and more specifically the cable  10  ( FIGS. 1 and 5 ). As described above, the central core  24  may provide insulation and/or shielding between the twisted pairs  26 . Although four are shown, each sub-cable  14  may include any number of twisted pairs  26 . 
     The end segment  48  of each separator  38  extends between the shield  30  and one or more of the twisted pairs  26 , and is optionally engaged with the shield  30  and/or the one or more twisted pairs  26 . Specifically, in the exemplary embodiment, the tip  53  of each finger segment  52  extends between the shield  30  and a corresponding one of the twisted pairs  26 . In the exemplary embodiment, each tip  53  is engaged with both the shield  30  and the corresponding twisted pair  26 . Alternatively, one or more of the tips  53  does not engage the shield  30  and/or the corresponding twisted pair  26 . Moreover, in some alternative embodiments, the central core  24  is configured to float within the passageway  62  of the shield  30  such that the tips  53  may move into and out of engagement with the shield  30 . Still further, in some alternative embodiments one or more of the twisted pairs  26  is configured to float within the corresponding channel  42  such that the one or more twisted pairs  26  can move into and out of engagement with the corresponding tips  53 . In addition or alternatively to the tips  53 , other portions of the finger segments  52  may extend between and/or engage the shield  30  and/or the corresponding twisted pair  26 . 
     As  FIG. 4  illustrates, each twisted pair  26  is spaced apart from the shield  30 . In other words, the twisted pairs  26  do not engage the shield  30 . The finger segments  52  provide the spacing by extending between the twisted pairs  26  and the shield  30  as described above. The finger segments  52  also hold the twisted pairs  26  within the channels  42  and prevent the twisted pairs  26  from moving closer (than the corresponding channel  42 ) to the shield  30 . Specifically, in the exemplary embodiment two finger segments  52  extend between each twisted pair  26  and the shield  30  to prevent the twisted pairs  26  from moving radially outward from the central longitudinal axis  40  into engagement with the shield  30 . The spacing between the twisted pairs  26  and the shield  30  may facilitate reducing an amount of cross talk between twisted pairs within the sub-cable  14  and/or between the twisted pairs  26  of different sub-cables  14  within the cable  10 . 
     The central core  24  and the twisted pairs  26  may be loaded into the passageway  62  of the shield  30  during a cabling operation. For example, the central core  24  and the twisted pairs  26  may be pulled into the passageway  62  during the cabling operation. Optionally, the central core  24  and the twisted pairs  26  are loaded into the passageway  62  simultaneously. Alternatively, the central core  24  is loaded into the passageway  62  either before or after the twisted pairs  26  are loaded into the passageway  62 . 
       FIG. 5  is a cross-sectional view of the cable  10 . The sub-cables  14  extend within the passageway  16  of the jacket  12  and are arranged radially about the central longitudinal axis  22  of the cable  10 . In the exemplary embodiment, the sub-cables  14  are arranged in a pattern about the axis  22  such that the sub-cables  14  are arranged evenly about the axis  22  in different quadrants thereof. In the pattern shown in herein, the sub-cables  14  are each engaged with adjacent sub-cables  14  and with the jacket  12  to facilitate holding the sub-cables  14  in position and maintaining the pattern. Alternatively, one or more of the sub-cables  14  is configured to float within the passageway  16  of the jacket  12  such that the one or more sub-cables  14  may move into and out of engagement with other sub-cables  14  and/or the jacket  12 . In alternative embodiments, the sub-cables  14  may be arranged in any other pattern about the axis  22  than is shown herein. Although four sub-cables  14  are shown, the cable  10  may include any number of sub-cables  14 . 
     Optionally, the cable  10  includes one or more drain wires  64  positioned within the passageway  16  of the jacket  12 . The drain wires  64  may provide a connection between the shields  30  of the sub-cables and a source of ground or other electrical energy. In the exemplary embodiment, the cable  10  includes four drain wires  64 , but the cable  10  may include any number of drain wires  64 . 
     The sub-cables  14  may be loaded into the passageway  16  of the jacket  12  during a cabling operation. For example, the sub-cables  14  may be pulled into the passageway  16  during the cabling operation. Optionally, the sub-cables  14  are loaded into the jacket  12  simultaneously with each other and/or the drain wires  64 . In some embodiments, the sub-cables  14  are loaded into the jacket  12  either before or after the drain wires  64  are loaded into the jacket  12 . 
     Referring again to  FIG. 1 , as described above, the jacket  12  and the insulative layers  32  at least partially surround the sub-cables  14  and the corresponding conductors  28 , respectively. Accordingly, in some embodiments, the jacket  12  surrounds only a portion of the circumference of the group of sub-cables  14  and/or the insulative layers  32  surround only a portion of the circumference of the corresponding conductors  28 . However, as shown in  FIG. 1 , the jacket  12  may surround an entirety of the circumference of the group of sub-cables  14 . Similarly, the insulative layers  32  may surround an entirety of the circumference of the corresponding conductors  28 , as also shown in  FIG. 1 .  FIG. 1  also illustrates each shield  30  extending around an entirety of the circumference of the corresponding central core  24  and twisted pairs  26 . However, each shield  30  may extend around only a portion of the circumference of the corresponding central core  24  and twisted pairs  26 . 
       FIG. 6  is a cross-sectional view of another exemplary embodiment of a cable  110 . In the description that follows, the cable  110  will be described and/or illustrated in terms of premise cabling, such as, but not limited to, a data communication cable and/or the like. However, it is to be understood that the benefits described and/or illustrated herein are also applicable to other types of cables, including, but not limited to, wires, cords, cables, and/or the like of any type. The following description and illustrations are therefore provided for illustrative purposes only and are but one potential application of the subject matter described and/or illustrated herein. 
     The cable  110  includes an insulative jacket  112  and a plurality of sub-cables  114  positioned within the jacket  112 . The jacket  112  at least partially surrounds the sub-cables  114 . Specifically, the jacket  112  includes an internal passageway  116  within which the sub-cables  114  extend. The sub-cables  114  extend within the passageway  116  along the length (only a portion of which is illustrated herein) of the cable  110 . In some embodiments, the jacket  112  surrounds only a portion of the circumference of the group of sub-cables  114 . However, as shown in  FIG. 6 , the jacket  112  may surround an entirety of the circumference of the group of sub-cables  114 . The jacket  112  is fabricated from any insulative, non-conductive materials, such as, but not limited to, PVC, polypropylene, a polymer, a fluoropolymer, a plastic, polyethylene, and/or the like. In the exemplary embodiment, the jacket  112  includes an approximately smooth inner surface  118  and an approximately smooth outer surface  120 . In alternative embodiments, the inner surface  118  and/or the outer surface  120  may not be approximately smooth. The cable  110  and the jacket  112  extend along a central longitudinal axis  122  that extends along the length of the cable  110 . Each sub-cable  114  may be referred to herein as a “cable”. 
     The cable  110  optionally includes a conductive shield  123  that at least partially surrounds the sub-cables  114  and is at least partially surrounded by the jacket  112 . In other words, the optional shield  123  extends radially (relative to the central longitudinal axis  122 ) between the jacket  112  and the sub-cables  114 . In some embodiments, the optional shield  123  surrounds only a portion of the circumference of the group of sub-cables  114 . However, as shown in  FIG. 6 , the optional shield  123  may surround an entirety of the circumference of the group of sub-cables  114 . The optional shield  123  is at least partially electrically conductive. The optional shield  123  may be partially electrically insulative. For example, the optional shield  123  may be fabricated entirely from one or more conductive materials or may include one or more conductive layers formed on one or more dielectric materials. The optional shield  123  may be fabricated from any materials, such as, but not limited to, a laminated metal tape, an aluminum polyimide laminated tape, an aluminum biaxially-oriented polyethylene terephthalate (BoPEt) laminated tape, a braid of conductive strands, fibers, and/or the like, a tube formed from a continuous (e.g., a sheet) conductive material, and/or the like. In embodiments wherein the optional shield  123  includes one or more conducive layers formed on one or more dielectric materials (e.g., a laminated metal tape), the conductive layer(s) may be located on a radially inner side of the shield  123  (i.e., facing radially toward the sub-cables  114 ) or a radially outer side of the shield  123  (i.e., facing radially away from the sub-cables  114 ). Optionally, the conductive layer(s) engages one or more of the outer shields  130  (described below) and/or one or more of the drain wires  164  (described below) to electrically connect the optional shield  123  to the shield(s)  130  and/or the drain wire(s)  164 . If the optional shield  123  is a tape, the tape may be wrapped around the sub-cables  114  in any manner, configuration, geometry, and/or the like, such as, but not limited to, a spiral (served) wrap, a cigarette wrap, and/or the like. 
     Optionally, and in addition or alternative to the optional shield  123 , the cable  110  includes an electrically insulative tape (not shown) that at least partially surrounds the sub-cables  114  and is at least partially surrounded by the jacket  112 . In some embodiments, the insulative tape surrounds only a portion of the circumference of the group of sub-cables  114 . But, the insulative tape may surround an entirety of the circumference of the group of sub-cables  114 . The insulative tape is fabricated from any insulative, non-conductive materials, such as, but not limited to, PVC, polypropylene, a polymer, a fluoropolymer, a plastic, polyethylene, and/or the like. The optional shield  123  may be referred to herein as a “second” outer shield and/or as a “tape”. The insulative tape described in this paragraph may be referred to herein as a “tape”. 
     Each of the sub-cables  114  includes a plurality of twisted pairs  126  of insulated conductors  128 , a plurality of at least partially electrically conductive inner shields  129 , and an at least partially electrically conductive outer shield  130 . In the exemplary embodiment, each of the conductors  128  is at least partially surrounded by an insulative layer  132 . In some embodiments, the insulative layers  132  surround only a portion of the circumference of the corresponding conductors  128 . However, as shown in  FIGS. 6 and 7 , the insulative layers  132  may surround an entirety of the circumference of the corresponding conductors  128 . The conductors  128  may be fabricated from any conductive materials, such as, but not limited to, copper and/or the like. The insulative layers  132  are fabricated from any insulative, non-conductive materials, such as, but not limited to, PVC, polypropylene, a polymer, a fluoropolymer, a plastic, polyethylene, and/or the like. The twisted pairs  126  may each be referred to herein as a “first”, a “second”, a “third”, and/or a “fourth” twisted pair. The inner shields  129  may each be referred to herein as a “first” and/or a “second” inner shield. Each of the outer shields  130  may be referred to herein as a “first” outer shield. 
       FIG. 7  is a cross sectional view or a portion of the cable  110  illustrating an exemplary embodiment of a sub-cable  114 . In the exemplary embodiment, the sub-cable  114  includes four twisted pairs  126 , lour inner shields  129 , and the outer shield  130 . Each of the inner shields  129  at least partially surrounds a corresponding twisted pair  126 . Specifically, the inner shields  129  include channels  131  within which the corresponding twisted pairs  126  extend. In some embodiments, the inner shields  129  surround only a portion of the circumferences of the corresponding twisted pairs  126 . But, and as shown in  FIG. 7 , each inner shield  129  may surround an entirety of the circumference of the corresponding twisted pair  126 . The inner shields  129  are physically located on the corresponding twisted pair  126 . In some embodiments, the inner shields  129  are engaged with the corresponding twisted pair  126 . Optionally, and as can be seen in  FIG. 7 , the inner diameters of the inner shields  129  are substantially similar to the diameter of the periphery of the corresponding twisted pair  126 . In the exemplary embodiment, only a single twisted pair  126  extends within the channel  131  of each inner shield  129 . In other words, for each inner shield  129 , no other twisted pair  126  besides the corresponding twisted pair  126  extends within the channel  131  in the exemplary embodiment. Accordingly, in the exemplary embodiment, each inner shield  129  does not surround any other twisted pair  126  besides the corresponding twisted pair  126 . Although four are shown, each sub-cable  114  may include any number of twisted pairs  126  and any number of the inner shields  129 . 
     Each inner shield  129  extends between the corresponding twisted pair  126  and the other twisted pairs  126  of the sub-cable  114  along at least a portion of the length of the cable  110  ( FIG. 6 ). Each inner shield  129  electrically shields the corresponding twisted pair  126  from the other twisted pairs  126  of the sub-cable  114 . The shielding of the twisted pairs  126  provided by the shields  129  may facilitate reducing an amount of cross talk between the twisted pairs  126  within the sub-cable  114  and/or between the twisted pairs  126  of different sub-cables  114  within the cable  110 . 
     Each of the inner shields  129  may be partially electrically insulative. For example, each of the inner shields  129  may be fabricated entirely from one or more conductive materials or may include one or more conductive layers formed on one or more dielectric materials. The inner shields  129  may each be fabricated from any materials, such as, but not limited to, a laminated metal tape, an aluminum polyimide laminated tape, an aluminum biaxially-oriented polyethylene terephthalate (BoPEt) laminated tape, a braid of conductive strands, fibers, and/or the like, a tube formed from a continuous (e.g., a sheet) conductive material, and/or the like. In embodiments wherein an inner shield  129  includes one or more conducive layers formed on one or more dielectric materials (e.g., a laminated metal tape), the conductive layer(s) may be located on a radially inner side of the inner shield  129  (i.e., facing radially toward the corresponding twisted pair  126 ) or a radially outer side of the inner shield  129  (i.e., facing radially away from the corresponding twisted pair  126 ). Optionally, the conductive layer(s) engage one or more of the corresponding outer shield  130  and/or the corresponding drain wire  133  (described below) to electrically connect the inner shield  129  to the outer shield  130  and/or the drain wire  133 . If an inner shield  129  is a tape, the tape may be wrapped around the corresponding twisted pair  126  in any manner, configuration, geometry, and/or the like, such as, but not limited to, a spiral (served) wrap, a cigarette wrap, and/or the like. 
     The outer shield  130  at least partially surrounds the twisted pairs  126  and the inner shields  129  of the sub-cable  114 . The outer shield  130  includes an internal passageway  162  within which the twisted pairs  126  and the inner shields  129  extend. In some embodiments, the outer shield  130  surrounds only a portion of the circumference of the twisted pairs  126  and inner shields  129  of the sub-cable  114 . However, as shown in  FIGS. 6 and 7 , each outer shield  130  may surround an entirety of the circumference of the corresponding group of twisted pairs  126  and inner shields  129 . The outer shield  130  shields the twisted pairs  126  within the sub-cable  114  from the twisted pairs  126  ( FIG. 6 ) of the other sub-cables  114  ( FIG. 6 ) of the cable  110 . The shielding provided by the outer shield  130  may facilitate reducing an amount of cross talk between the twisted pairs  126  of the sub-cable  114  and the twisted pairs  126  of different sub-cables  114  within the cable  110 . 
     The outer shield  130  may be partially electrically insulative. For example, the outer shield  130  may be fabricated entirely from one or more conductive materials or may include one or more conductive layers formed on one or more dielectric materials. The outer shield  130  may be fabricated from any materials, such as, but not limited to, a laminated metal tape, an aluminum polyimide laminated tape, an aluminum biaxially-oriented polyethylene terephthalate (BoPEt) laminated tape, a braid of conductive strands, fibers, and/or the like, a tube formed from a continuous (e.g., a sheet) conductive material, and/or the like. In embodiments wherein the outer shield  130  includes one or more conducive layers formed on one or more dielectric materials (e.g., a laminated metal tape), the conductive layer(s) may be located on a radially inner side of the outer shield  130  (i.e., facing radially toward the twisted pairs  126 ) or a radially outer side of the outer shield  130  (i.e., facing radially away from the twisted pairs  126 ). Optionally, the conductive layer(s) engage one or more of the corresponding inner shields  129 , the optional shield  123 , one or more of the drain wires  164 , and/or the corresponding drain wire  133  to electrically connect the outer shield  130  to the corresponding inner shield(s)  129 , the drain wire(s)  164 , the corresponding drain wire  133 , and/or the optional shield  123 . When the outer shield  130  is a tape, the tape may be wrapped around the twisted pairs  126  and the inner shields  129  in any manner, configuration, geometry, and/or the like, such as, but not limited to, a spiral (served) wrap, a cigarette wrap, and/or the like. 
     Optionally, one or more of the inner shields  129  and/or the outer shield  130  is electrically connected to a ground or other source of electrical energy to provide active shielding. For example, the sub-cable  114  optionally includes one or more drain wires  133  positioned within the passageway  162  of the outer shield  130  between the inner shields  129  and the outer shield  130 . The drain wires  133  may provide a connection between the inner shields  129  and/or the outer shield  130  and a source of ground or other electrical energy. In the exemplary embodiment, the sub-cable  114  includes one drain wire  133 , but the sub-cable  114  may include any number of drain wires  133 . 
     In the exemplary embodiment, the drain wire  133  is spirally wrapped (served) around the twisted pairs  126  and the inner shields  129 . However, the drain wire  133  may be wrapped in any manner, configuration, geometry, and/or the like, such as, but not limited to, a cigarette wrap and/or the like. Moreover, the drain wire  133  is not limited to being wrapped around the twisted pairs  126  and the inner shields  129 . Rather, in some embodiments, the drain wire  133  extends along a path that is approximately parallel to the length of the sub-cable  114  (e.g., approximately parallel to the central longitudinal axis  122 ). The exemplary drain wire  133  is shown as including seven strands of material. However, the drain wire  133  may include any number of strands of material. 
     The inner shields  129  optionally engage the outer shield  130 . In some embodiments, the inner shields  129  are configured to float within the internal passageway  162  of the outer shield  130  into and out of engagement with the outer shield  30 . In other embodiments, the inner shields  129  are tightly packed within the outer shield  130  such that the inner shields  129  are engaged with the outer shield  130  along a majority, or an approximate entirety, of the length of the sub-cable  114 . In still other embodiments, the inner shields  129  are spaced apart from the outer shield  130  along a majority, or an approximate entirety, of the length of the sub-cable  114 . 
     The inner shields  129  are optionally electrically connected to the outer shield  130 . For example, the inner shields  129  may be electrically connected to the outer shield  130  via engagement between the inner shields  129  and the outer shield  130 , via the drain wire  133 , and/or the like. 
     The twisted pairs  126  and the inner shields  129  may be loaded into the passageway  162  of the shield  130  during a cabling operation. For example, the twisted pairs  126  and the inner shields  129  may be pulled into the passageway  162  during the cabling operation. Optionally, the twisted pairs  126  and the inner shields  129  are loaded into the passageway  162  simultaneously. Alternatively, the inner shields  129  are loaded into the passageway  162  either before or after the twisted pairs  126  are loaded into the passageway  162 . 
     Referring again to  FIG. 6 , the sub-cables  114  extend within the passageway  116  of the jacket  112  and are arranged radially about the central longitudinal axis  122  of the cable  110 . In the exemplary embodiment, the sub-cables  114  are arranged in a pattern about the axis  122  such that the sub-cables  114  are arranged evenly about the axis  122  in different quadrants thereof. In the pattern shown herein, the sub-cables  114  are each engaged with adjacent sub-cables  114  and with the optional shield  123  (or the jacket  112  or the insulative tape) to facilitate holding the sub-cables  114  in position and maintaining the pattern. Alternatively, one or more of the sub-cables  114  is configured to float within the passageway  116  of the jacket  112  such that the one or more sub-cables  114  may move into and out of engagement with other sub-cables  114  and/or the optional shield  123  (or the insulative tape or the jacket  112 ). In alternative embodiments, the sub-cables  114  may be arranged in any other pattern about the axis  122  than is shown herein. Optionally, one or more filler elements  135  are positioned within the internal passageway  116  of the jacket  112 , for example to facilitate holding the sub-cables  114  within the pattern, to facilitate providing the cable  110  with a predetermined shape (e.g., cylindrical), and/or the like. Although four sub-cables  114  are shown, the cable  110  may include any number of sub-cables  114 . 
     Optionally, the cable  110  includes one or more drain wires  164  positioned within the passageway  116  of the jacket  112  between the sub-cables  114  and the jacket  112 . The drain wires  164  may provide a connection between the outer shields  130  of the sub-cables  114  and a source of ground or other electrical energy. In the exemplary embodiment, the sub-cable  114  includes four drain wires  164 , but the sub-cable  114  may include any number of drain wires  164 . In the exemplary embodiment, the drain wires  164  extend along paths that are approximately parallel to the length of the cable  110  (e.g., approximately parallel to the central longitudinal axis  122 ). But, the drain wires  164  may be wrapped around the sub-cables  114 , such as, but not limited to, a spiral (served) wrap, a cigarette wrap, and/or the like. The exemplary drain wires  164  are shown as including one strand of material. However, the drain wire  164  may include any number of strands of material. 
     Each of the filler elements  135  may be fabricated from one or more dielectric materials such that the tiller element  135  is at least partially insulative and non-conductive. In addition or alternative to the dielectric materials, each of the filler elements  135  may include conductive materials such that the filler element  135  is at least partially electrically conductive. For example, each of the filler elements  135  may be fabricated entirely from one or more conductive materials or may include one or more conductive layers formed on one or more dielectric materials. Optionally, when a filler element  135  is at least partially electrically conductive, the filler element  135  may engage and thereby electrically connect two or more of the outer shields  130  together. Moreover, and optionally, when a filler element  135  is at least partially electrically conductive the filler element  135  may serve as a drain wire, for example in addition or alternatively to one or more of the drain wires  164 . 
     The sub-cables  114  may be loaded into the passageway  116  of the jacket  112  during a cabling operation. For example, the sub-cables  114  may be pulled into the passageway  116  during the cabling operation. Optionally, the sub-cables  114  are loaded into the jacket  112  simultaneously with each other and/or the drain wires  164 . In some embodiments, the sub-cables  114  are loaded into the jacket  112  either before or after the drain wires  164  are loaded into the jacket  112 . 
     The embodiments described and/or illustrated herein may provide a cable having an improved electrical performance as compared with at least some known cables. For example, the embodiments described and/or illustrated herein may provide a cable having a reduced amount of crosstalk and/or an increased amount of crosstalk isolation than at least some known cables. The embodiments described and/or illustrated herein may provide a cable having more than four twisted pairs of insulated conductors that complies with ISO/IEC 11801. The embodiments described and/or illustrated herein may provide a cable having more than four twisted pairs of insulated conductors that complies with ISO/IEC CAT7A. The embodiments described and/or illustrated herein may provide a cable that is configured to conduct electrical data signals at a rate of at least 1 Megahertz. The embodiments described and/or illustrated herein may provide a cable that is configured to conduct electrical data signals at a rate of at least 1 Gigahertz. 
     It is to be understood that the above description is intended to be illustrative, and not restrictive. For example, the above-described embodiments (and/or aspects thereof) may be used in combination with each other. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the subject matter described and/or illustrated herein without departing from its scope. Dimensions, types of materials, orientations of the various components, and the number and positions of the various components described and/or illustrated herein are intended to define parameters of certain embodiments, and are by no means limiting and are merely exemplary embodiments. Many other embodiments and modifications within the spirit and scope of the claims will be apparent to those of skill in the art upon reviewing the above description and the drawings. The scope of the subject matter described and/or illustrated herein should, therefore, be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. In the appended claims, the terms “including” and “in which” are used as the plain-English equivalents of the respective terms “comprising” and “wherein.” Moreover, in the following claims, the terms “first,” “second,” and “third,” etc. are used merely as labels, and are not intended to impose numerical requirements on their objects. Further, the limitations of the following claims are not written in means—plus-function format and are not intended to be interpreted based on 35 U.S.C. §112, sixth paragraph, unless and until such claim limitations expressly use the phrase “means for” followed by a statement of function void of further structure.