WO2016077223A1 - Power/fiber hybrid cable - Google Patents

Abstract

A hybrid cable is provided that transmits both electrical and optical signals. The hybrid cable includes a centrally located optical fiber and coaxially arranged conductive laminates that are insulated from each other.

Description

POWER/FIBER HYBRID CABLE

CROSS REFERENCE TO RELATED APPLICATION

This application is being filed on November 9, 2015 as a PCT International Patent Application and claims the benefit of U.S. Patent Application Serial No.

62/078,207, filed on November 11, 2014, the disclosure of which is incorporated herein by reference in its entirety.

TECHNICAL FIELD

The present disclosure relates generally to hybrid communication systems. More particularly, the present disclosure relates to telecommunications cables capable of transmitting both optical signals and electrical power.

BACKGROUND

Rapid growth of portable high-speed wireless transceiver devices (e.g., smartphones, tablets, laptop computers, etc.) continues in today's market, thereby creating higher demand for untethered contact. Thus, there is growing demand for integrated voice, data and video capable of being transmitted wirelessly at high data transmission rates. Providing the bandwidth needed to support this demand will require cost effective and efficient deployment of additional fixed location transceivers (i.e., cell sites or nodes) generating both large and small wireless coverage areas. Telecommunications cables capable of transmitting both electrical power and optical signals that are capable of being manufactured and installed in an effective, cost effective manner can greatly enhance the ability of service providers to implement coverage areas suitable for meeting growing market demands.

SUMMARY

One aspect of the present disclosure relates to a cable that transmits both electrical power and optical communications. In certain examples, the electrical power and optical communications can be directed to a device for generating a cellular coverage area (e.g., a macrocell, a microcell, a metrocell, a picocell, a femtocell, etc.).

Another aspect of the present disclosure relates to telecommunications cables that facilitate the fast, low cost and simple deployment of optical fiber and power to interface with active devices such as devices for generating wireless communication coverage areas (e.g., wireless transceivers) and other active devices (e.g., cameras).

Still other aspects of the present disclosure relate to hybrid power/optical fiber cables that facilitate the deployment of wireless communication coverage areas at various locations such as stadiums, shopping areas, hotels, high rise office buildings, multi-dwelling units, suburban environments, corporate and university campuses, in- building areas, near-building areas, tunnels, canyons, roadside areas and coastal areas. Still further aspects of the present disclosure relate to power/optical fiber hybrid cables that enhance the coverage areas provided by cellular technologies (e.g., GSM, CDMA, UMTS, LTE, WiMax, WiFi, etc.).

A variety of additional inventive aspects will be set forth in the description that follows. The inventive aspects can relate to individual features and to combinations of features. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the broad inventive concepts upon which the examples disclosed herein are based.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a system diagram showing an example distribution of wireless coverage areas deployed using a hybrid cable system in accordance with the principles of the present disclosure; and

FIG. 2 is a transverse cross-sectional view of a power/optical fiber hybrid cable in accordance with the principles of the present disclosure.

DETAILED DESCRIPTION

Various examples will be described in detail with reference to the figures, wherein like reference numerals represent like parts and assemblies throughout the several views. Any examples set forth in this specification are not intended to be limiting and merely set forth some of the many possible variations of the inventive aspects disclosed herein.

FIG. 1 shows a system 10 in accordance with the principles of the present disclosure for enhancing the coverage areas provided by cellular technologies (e.g., GSM, CDMA, UMTS, LTE, WiMax, WiFi, etc.). The system 10 includes a base location 11 (i.e., a hub) and a plurality of wireless coverage area defining equipment 12a, 12b, 12c, 12d, 12e and 12f distributed about the base location 11. In certain examples, the base location 11 can include a structure 14 (e.g., a closet, hut, building, housing, enclosure, cabinet, etc.) protecting telecommunications equipment such as racks, fiber optic adapter panels, passive optical splitters, wavelength division multi-plexers, fiber splice locations, optical fiber patching and/or fiber interconnect structures and other active and/or passive equipment. In the depicted example, the base location 11 is connected to a central office 16 or other remote location by a fiber optic cable such as a multi-fiber optical trunk cable 18 that provides high bandwidth two-way optical communication between the base location 11 and the central office 16 or other remote location. In the depicted example, the base location 11 is connected to the wireless coverage area defining equipment 12a, 12b, 12c, 12d, 12e and 12f by hybrid cables 20. The hybrid cables 20 are each capable of transmitting both power and communications between the base location 11 and the wireless coverage area defining equipment 12a, 12b, 12c, 12d, 12e and 12f.

The wireless coverage area defining equipment 12a, 12b, 12c, 12d, 12e and 12f can each include one or more wireless transceivers 22. The transceivers 22 can include single transceivers 22 or distributed arrays of transceivers 22. As used herein, a "wireless transceiver" is a device or arrangement of devices capable of transmitting and receiving wireless signals. A wireless transceiver typically includes an antenna for enhancing receiving and transmitting the wireless signals. Wireless coverage areas are defined around each of the wireless coverage area defining equipment 12a, 12b, 12c, 12d, 12e and 12f. Wireless coverage areas can also be referred to as cells, cellular coverage areas, wireless coverage zones, or like terms. Examples of and/or alternative terms for wireless transceivers include radio-heads, wireless routers, cell sites, wireless nodes, etc.

In the depicted example of FIG. 1, the base location 11 is shown as a base transceiver station (BTS) located adjacent to a radio tower 24 supporting and elevating a plurality of the wireless coverage area defining equipment 12a. In one example, the equipment 12a can define wireless coverage areas such as macrocells or microcells (i.e., cells each having a coverage area less than or equal to about 2 kilometers wide). The wireless coverage area defining equipment 12b is shown deployed at a suburban environment (e.g., on a light pole in a residential neighborhood) and the equipment 12c is shown deployed at a roadside area (e.g., on a roadside power pole). The equipment 12c could also be installed at other locations such as tunnels, canyons, coastal areas, etc. In one example, the equipment 12b, 12c can define wireless coverage areas such as microcells or picocells (i.e., cells each having a coverage area equal to or less than about 200 meters wide). The equipment 12d is shown deployed at a campus location (e.g., a university or corporate campus), the equipment 12e is shown deployed at a large public venue location (e.g., a stadium), and the equipment 12f is shown installed at an in-building or near-building environment (e.g., multi-dwelling unit, high rise, school, etc.). In one example, the equipment 12d, 12e, and 12f can define wireless coverage areas such as microcells, picocells, or femtocells (i.e., cells each having a coverage area equal to or less than about 10 meters wide).

Referring to FIG. 2 a hybrid cable 20 according to an embodiment of the present disclosure is shown in cross section. In the depicted embodiment, the hybrid cable 20 includes an optical fiber 32. The optical fiber 32 includes a glass core 36 that defines a central longitudinal axis 34 of the hybrid cable 20. In the depicted embodiment, the optical fiber 32 also includes a cladding glass layer 38 disposed around the core 36 and a first protective coating layer 40 (e.g., acrylate) disposed around the cladding layer 38. A buffer layer 42 is extruded over the coating layer 40. It should be appreciated that many other configurations are also possible. For example, in some embodiments multiple optical fibers may be provided in the cable rather than a single optical fiber.

In the depicted embodiment the protective coating layer 40 has a polymeric construction. In the depicted embodiment this protective coating layer 40 is bonded to the cladding layer 38. In the depicted embodiment, protective coating layer 40 serves to protect the optical fiber 36 as it is handled and integrated into the hybrid cable. The protective coating layer 40 facilitates the handling of the optical fiber 36 so that it does not become damaged as it avoids direct handling of the glass portions of the optical fiber. In one example the outer cross-sectional diameter of the protective coating layer can be between 200-300 microns.

In the depicted embodiment, the hybrid cable includes a buffer layer 42, which may be bonded to the protective coating layer 40. The bonding of the coating and buffer protective layers prevents the optical fiber 32 from slipping longitudinally. The bonding limits relative motion between the buffer layer and the protective coating layers. In the depicted embodiment, the buffer layer 42 is a tight buffer fiber layer. In other examples, a loose buffer or semi tight buffer may be used. In the depicted embodiment the maximum cross-section diameter of the buffer layer 42 is between 400-1000, 400-900 or 400-600 microns. It should be appreciated that many other configurations are possible including configurations that do not include a buffer layer as described above.

In the depicted embodiment, the hybrid cable includes a strength layer 44 disposed around the buffered optical fiber 32. In the depicted embodiment the strength layer 44 is directly adjacent the buffer layer 42. The strength layer assembly can include tensile reinforcing members 46 in a spaced apart arrangement around the buffer layer 42. The strength layer 44 functions to strengthen the hybrid cable and enable it to withstand relatively high tensile forces without causing damage to internal components of the hybrid cable 20. In certain examples, the tensile reinforcing members can include strands/rovings formed by reinforcing fibers such as aramid yarn, E-glass, S-glass or like structures. The reinforcing fibers can include continuous filaments. In certain example, the reinforcing fibers/ members can be joined together as a binder or matrix material such that the reinforcing layer is defined by a reinforcing tape having a uniform distribution of reinforcing fibers disposed around the buffer layer 42. The tape layer can extend three hundred and sixty degrees around the longitudinal axis of the cable and can have a seam joint such as a butt-joint, an overlap joint that is parallel to the longitudinal axis, or a joint that extends helically about the longitudinal axis.

In the depicted embodiment, a first tape layer 50 is disposed around the strength layer 44, the first tape layer including a conductive layer 58 bonded to a non- conductive substrate layer 56. In the depicted embodiment, the first tape layer 50 is arranged such that the conductive layer 58 of the first tape faces inwardly towards the central axis 34 of the hybrid cable 20, and the non-conductive substrate layer 56 of the first tape layer 50 faces outwardly away from the central axis 34 of the hybrid cable 20. In one example embodiment, the outer cross-sectional diameter of the first tape layer is between 2.5-3.0 millimeters. It should be appreciated that many other alternative configurations are possible.

In the depicted embodiment, a second tape layer 48 is disposed around the first tape layer 50, the second tape layer 48 including a conductive layer 52 bonded to a non-conductive substrate layer 54. The second tape layer is arranged such that the conductive layer 52 of the second tape faces outwardly away from the central axis 34 of the hybrid cable 20, and the non-conductive substrate layer 54 of the second tape layer 48 faces inwardly towards the central axis 34 of the hybrid cable 20.

In the depicted embodiment, the hybrid cable 20 includes a cable jacket 64 disposed around the second tape layer 48. In one example embodiment, the outer cross- sectional diameter of the outer cable jacket can be between 4.0-6.0 millimeters. It should be appreciated that many other alternative configurations are possible.

In certain examples, the tape layers 48, 50 can extend 360 degrees about the axis 34 and can have a seam joint such as a butt-joint, an overlap joint that is parallel to the longitudinal axis 34, or a joint that extends helically about the axis 34. In certain examples, the joints of the tapes 48, 50 are rotationally offset from one another. In one example, the joints of the tapes 48, 50 are rotationally offset about 180 degrees relative to each other. The copper laminates are configured to carry at least 10 watts of electrical power. In some applications a fiber optic connector is mounted at an end of the cable 20, and the first tape layer is connected to ground and the second tape layer is connected to an electrical power source or vise versa.

It should be appreciated that the terms 'tape' and 'laminate' are used interchangeably herein. In one embodiment the first and second tapes (also referenced as laminates) are available commercially by Neptco Incorporated sold as Shielding Tape— Standard Film/Foil Laminates (trade name Netape). The material is a high strength copper laminate typically used as a salt corrosion resistant shield in military cable applications. The construction includes a 23 micron polyester film bonded to a 36 micron

electrodeposited copper foil. As used herein the meaning of conductor means electrically conductive and non-conductive means eclectically non-conductive. The non-conductive layer can also be referred to as an insulating layer or a dielectric layer.

Parts List:

10 System

11 Base location (hub)

12a wireless coverage area defining equipment (e.g., cell tower)

12b wireless coverage area defining equipment (e.g., residential light pole)

12c wireless coverage area defining equipment (e.g., roadside power pole)

12d wireless coverage area defining equipment (e.g., corp or edu campus location)

12e wireless coverage area defining equipment (e.g., stadium)

12f wireless coverage area defining equipment (e.g., high rise/apt bldg/school)

14 Structure (closet/hut/bldg/enclosure/etc.

16 Central Office

18 Multi-fiber optical trunk cable

20 Hybrid cables

22 Transceivers

24 Radio tower

32 optical fiber

34 central axis (of hybrid cable 20)

36 glass core

38 cladding glass layer

40 protective coating layer

42 buffer layer

44 strength layer assembly

46 aramid fibers

48 2nd tape layer

50 1st tape layer

52 conductive layer

54 non-conductive substrate layer

56 non-conductive substrate layer

58 conductive layer

60 non-conductive layer (between 50 and 48 tape layers)

62 air space (between 64 and 48)

64 cable jacket Various modifications and alterations of this disclosure will become apparent to those skilled in the art without departing from the scope and spirit of this disclosure, and it should be understood that the scope of this disclosure is not to be unduly limited to the illustrative examples set forth herein.

Claims

WHAT IS CLAIMED IS:

1. A hybrid cable comprising:

an optical fiber;

a strength layer disposed around the optical fiber;

a first tape layer disposed around the strength layer, the first tape layer including a conductive layer bonded to a non-conductive substrate layer, the first tape layer arranged such that the conductive layer of the first tape faces inwardly towards a central axis of the hybrid cable and the non-conductive substrate layer of the first tape faces outwardly away from the central axis of the hybrid cable;

a second tape layer disposed around the first tape layer, the second tape layer including a conductive layer bonded to a substrate layer, the second tape layer arranged such that the conductive layer of the second tape layer faces outwardly away from the central axis of the hybrid cable and the non-conductive substrate layer of the second tape layer faces inwardly towards the central axis of the hybrid cable, wherein the first tape layer is located between the strength layer assembly and the second tape layer; and

a cable jacket disposed around the second tape layer.

2. The hybrid cable of claim 1, further comprising a buffer layer disposed around the optical fiber.

3. The hybrid cable of claim 2, wherein the buffer layer is bonded to the optical fiber.

4. The hybrid cable of claim 1, wherein the first and second tape layers are conductive copper laminates.

5. The hybrid cable of claim 1, wherein the cable has a circular cross section.

6. The hybrid cable of claim 1, wherein hybrid cable comprises only a single optical fiber.

7. The hybrid cable of claim 2, wherein an outer cross-section diameter of the buffer layer is between 400-600 microns.

8. The hybrid cable of claim 1, wherein an outer cross-sectional diameter of the first tape layer is between 2.5-3.0 millimeters.

9. The hybrid cable of claim 1, wherein an outer cross-sectional diameter of the outer cable jacket is between 4.0-6.0 millimeters.

10. The hybrid cable of claim 1, wherein the first and second tape layers are configured to carry at least 10 watts of electrical power.

11. A hybrid cable, comprising:

an optical fiber that defines a central longitudinal axis of the hybrid cable;

a strength layer;

a first laminate disposed around the strength layer, the first laminate layer including a conductive layer bonded to a non-conductive substrate layer, the first laminate arranged such that the conductive layer faces inwardly towards the central longitudinal axis of the hybrid cable and the non-conductive substrate layer faces outwardly away from the central longitudinal axis of the hybrid cable;

a second laminate disposed around the first laminate, the second laminate including a conductive layer bonded to a substrate layer, the second laminate arranged such that the conductive layer of the second laminate outwardly away from the central axis and the non-conductive substrate layer of the second laminate faces inwardly towards the central axis; and

a cable jacket disposed around the second laminate, the cable jacket including a circular cross-sectional shape.

12. The hybrid cable of claim 11 , wherein the buffer layer is a tight buffered fiber layer.

13. The hybrid cable of claim 11, wherein the first and second laminates are configured to carry at least 10 watts of electrical power.