WO2017103342A1

WO2017103342A1 - Cable divider and cable arrangement

Info

Publication number: WO2017103342A1
Application number: PCT/FI2016/050888
Authority: WO
Inventors: Esa VEIJALAINEN
Original assignee: Helkama Bica Oy
Priority date: 2015-12-17
Filing date: 2016-12-16
Publication date: 2017-06-22

Abstract

A cable divider (5), comprising a casing (11), comprising a feeder cable port (12) for receiving a feeder cable system (6), a power jumper port (13) for receiving a power jumper (14), and an optical jumper port (15) for receiving an optical jumper (16). The casing (11) establishes a shielded interior against environmental dust and/or water, the cable divider (5) further comprising a power conductor terminal unit (19) for connecting a power conductor (8) of a feeder cable system (6) to the power jumper (14), an optical fiber adapter unit (20) for connecting an optical fiber of a feeder cable system (6) to a fiber jumper, said power conductor terminal unit (19) and optical fiber adapter unit (20) being arranged in the interior. The casing (11) is arranged to enable the protection classification of the divider higher than the protection classification of the power conductor terminal unit (19) and/or optical fiber adapter unit (20).

Description

Cable divider and cable arrangement

Background

The invention relates to a cable divider.

The invention further relates to a cable arrangement.

So called remote radio heads (RRH) in antenna towers are commonly known. The remote radio head in general contains the base station's RF circuitry and analog-to-digital/digital-to-analog converters and up/down converters. RRHs have a standardized optical interface to connect to the rest of the base station. The transmission and amplification components are located to the top of the tower in order to reduce the signal losses and power requirements. Furthermore, it is necessary to run a DC power cable up the tower in order to boost the signal power to the individual amplifiers.

Thus there are various systems for connecting the transmission and amplification components located to the top of the tower to the rest of the base station equipment that are typically located in an equipment room at the base of the tower.

A problem with these systems is that they are expensive and troublesome to procure, install and maintain, they take a lot of space and cause windload and fiber optic wires cannot be added afterwards without installing additional cable.

Brief description

Viewed from a first aspect, there can be provided a cable divider, comprising a casing, comprising a feeder cable port for receiving a feeder cable system, a power jumper port for receiving a power jumper, an optical jump- er port for receiving an optical jumper, the casing establishing a shielded interior against environmental dust and/or water, the cable divider further comprising a power conductor terminal unit for connecting a power conductor of a feeder cable system to the power jumper, and an optical fiber adapter unit for connecting an optical fiber of a feeder cable system to a fiber jumper, said power conductor terminal unit and optical fiber adapter unit being arranged in the interior, and the casing being arranged to enable the protection classification of the divider higher than the protection classification of the power conductor terminal unit and/or optical fiber adapter unit.

Thereby a cable divider that has low manufacturing, installing and maintaining costs may be achieved. Viewed from a further aspect, there can be provided a cable arrangement, comprising the cable divider as claimed in the claims attached herein, the cable arrangement further comprising a feeder cable system arranged in the feeder cable port, a power conductor of the feeder cable system being connected to the power conductor terminal unit, and an optical fiber of the feeder cable system being connected to the optical fiber adapter unit.

Thereby a cable arrangement that is easy to procure, install and maintain may be achieved.

The cable divider and the arrangement are characterised by what is stated in the characterising parts of the independent claims. Some other embodiments are characterised by what is stated in the other claims. Inventive embodiments are also disclosed in the specification and drawings of this patent application. The inventive content of the patent application may also be defined in other ways than defined in the following claims. The inventive con- tent may also be formed of several separate inventions, especially if the invention is examined in the light of expressed or implicit sub-tasks or in view of obtained benefits or benefit groups. Some of the definitions contained in the following claims may then be unnecessary in view of the separate inventive ideas. Features of the different embodiments of the invention may, within the scope of the basic inventive idea, be applied to other embodiments.

Brief description of figures

Some embodiments illustrating the present disclosure are described in more detail in the attached drawings, in which

Figure 1 is a schematic side view of an example cable arrangement adapted in an antenna tower,

Figure 2 is a schematic side view of a cable divider in partial cross- section, and

Figure 3 is another schematic side view of the cable divider shown in Figure 2 in partial cross-section.

In the figures, some embodiments are shown simplified for the sake of clarity. Similar parts are marked with the same reference numbers in the figures.

Detailed description

Figure 1 is a schematic side view of an example cable arrangement adapted in an antenna tower. As used herein, the term "power conductor", "electrical conductor" and/or power jumper include all types of cables and/or conductors used to transmit electrical power manufactured of any conductive material, including without limitation, copper and aluminum and in any form, including without limi- tation, multiple or individual conductors and whether jacketed, armored, and/or the like.

As used herein, terms "fiber optic cable", "optical fiber" and/or "optical jumper" include all types of single mode and multi-mode light waveguides, including one or more optical fibers that may be up-coated, colored, buffered, ribbonized and/or have other organizing or protective structure in a cable such as one or more tubes, strength members, jackets or the like.

Figure 1 illustrates a cell tower site 100 of a wireless service provider (WSP) or any other outdoor structure, which has active equipment requiring optical transmission and electric power feeding.

The cell tower site 100 comprises a tower 1 , an equipment room 2, an antenna 3, and a cable arrangement 4.

The cable arrangement 4 comprises a cable divider 5, and a feeder cable system 6. The cable divider 5 is arranged up to the tower 1 , e.g. nearby antenna or RRH level 7.

According to an embodiment, as shown in Figure 1 , the feeder cable system 6 is a hybrid cable that comprises at least one power conductor 8 and at least one optical fiber 9. The hybrid cable means the combination of fiber optic, including without limitation, optical fiber, cables, connections, and/or components, and electrical power, including, without limitation conductors, ca- bles, connections and/or components. In an embodiment, the hybrid cable has a structure where the optical fiber(s) 9 are surrounded by the power conductors) 8. An advantage is that the optical fiber(s) 9 are well protected against environmental stresses, especially against attacks by animals, such as monkeys or birds.

According to another embodiment, the feeder cable system 6 comprises at least one power conductor and at least one optical fiber separate from the at least one power conductor.

The feeder cable system 6 extends from the equipment room 2to the cable divider 5. The cable divider 5 is connected to the antenna 3 or a remote radio head (RRH) 10. The cable divider 5 extends the at least one power conductor 8 and the at least one optical fiber 9 to said remote radio head (RRH) 10.

The at least one power conductor 8 provides the electrical power necessary to operate the RRH 10. The at least one optical fiber 9 carries optical communication signals between the BTS 2 and the RRH 10.

In an embodiment, the cable arrangement 4 is a factory preassem- bled system. This means that at least the feeder cable system 6 is connected to the cable divider 5.

An advantage is that the assembly and quality inspection work can be done in a clean, tested and high quality environment. In another embodiment, the cable arrangement 4 is assembled at or nearby the cell tower site 100.

Figure 2 is a schematic side view of a cable divider in partial cross- section, and Figure 3 is another schematic side view of the cable divider shown in Figure 2 in partial cross-section.

The cable divider 5 has a casing 1 1 that is manufactured from metal or metal alloy, such as aluminum alloy, plastic or composite material. The cable divider 5 comprises at least one feeder cable port 12 for receiving the feeder cable system described above. The embodiment shown in Figure 2 comprises one feeder cable port 12. In an embodiment, the feeder cable port

12 is arranged for receiving a hybrid feeder cable as shown in Figure 2.

The casing 1 1 establishes a shielded interior 17 against environmental dust and/or water. The casing 1 1 may comprise an opening 26 that makes it possible to access from outside into the shielded interior 17 and components therein. The opening 26 is closable so that requirements for the weatherproofness of the casing 1 1 are met. In an embodiment, the casing 1 1 comprises a lid 18 that is repeatedly openable. The lid 18 may be attached to the rest of the casing 1 1 by a hinge and lockable by a latch or any known lock- ing means, or by screw or any known attaching means.

In an embodiment, the casing 1 1 comprises a pressure valve 27 that allows the pressure in the interior 17 to be equilibrium with the surroundings. An advantage is that humidity problems caused by pressure differences can be avoided.

The cable divider 5 also comprises at least one power jumper port

13 for receiving a power jumper 14, and at least one optical jumper port 15 for receiving an optical jumper 16. The embodiment shown in Figure 2 comprises one power jumper port 13 and one optical jumper port 15. In another embodiment, the cable divider 5 comprises at least two power jumper ports 13 and at least two optical jumper ports 15.

According to an idea, the jumper port 13, 15 may have capacity to receive two or even more jumpers 14, 16, respectively.

In the embodiment shown in Figure 2, the feeder cable port 12 is adapted to a first end 21 of the casing, the optical jumper port to a first side 23 of the casing, and the power jumper port to a second side 24 of the casing, opposite to said first side 23. A pulling element 25 is arranged to a second end 22 of the casing. The pulling element 25 may comprise a lifting lug or hole, or any suitable lifting assembly. The pulling element 25 and the overall structure of the casing is dimensioned for hoisting the cable divider 5 and the feeder cable system 6 up to the tower 1 . According to an idea, the pulling element 25 and the casing 1 1 are dimensioned for pulling force up to 4000 N.

In an embodiment, as the cable divider 5 is attached to its place in the tower 1 , the first end 21 of the casing is directed downwards, e.g. at the ground. Furthermore, the power jumper ports 13 and the optical jumper ports 15 may be directed obliquely downwards, as shown in Figure 3. An advantage is that rain will not fall into the ports 12, 13 and 15. It is to be noted, however, that the ports may comprise sealing arrangements for sealing the ports against water and dust. The ports 12, 13 and 15 may comprise a cable gland known per se. In an embodiment, the power jumper port(s) 13 comprises a cable gland where the power jumper(s) is/are grounded. Thus only one grounding cable is needed to ground the divider 5 to the tower 1 .

Furthermore, the cable divider 5 comprises a least one power conductor terminal unit 19 for connecting a power conductor 8 of the feeder cable system 6 to the power jumper 14, and at least one optical fiber adapter unit 20 for connecting an optical fiber 9 of the feeder cable system 6 to the optical jumper 16. In an embodiment at least one of the power conductor terminal unit 19 and the optical fiber adapter unit 20 is connectable to the corresponding jumper 14, 16 using standard connectors. This enables an easy and quick connection work in the cable divider 5.

In an embodiment, the power conductor terminal unit 19 may be a screw or spring terminal. In an embodiment, the optical fiber adapter unit 20 may be of LC type. Alternatively, the optical fiber adapter unit 20 may be any other standard optical connector.

At the cable divider 5, or in the interior 17, certain of the electrical power conductors 8 and certain of the optical fibers 9 may separate from the feeder cable system 6. Said separated power conductors 8 and the optical fibers 9 are connected to connectors in the power conductor terminal unit 19 and optical fiber adapter unit 20, respectively.

The power conductor terminal unit 19 and optical fiber adapter unit 20 are arranged in the interior 17 such that at least the jumpers 14, 16 can be connected to and/or released from the corresponding unit 19, 20.

In an embodiment, the power conductor terminal unit 19 and optical fiber adapter unit 20 may not have any IP classification, because they may be designed for indoor use only.

In an embodiment, the casing 1 1 is classified according to IP65. In another embodiment, the casing in classified to even higher classification, e.g. to IP66.

Thus the casing 1 1 enables the protection classification of the cable divider 5 higher than the protection classification, if any, of the power conduc- tor terminal unit 19 and/or optical fiber adapter unit 20. Thus cheaper components may be arranged in the interior 1 1 without compromising the weather- proofness of the cable divider 5 and the cable arrangement 4.

In an embodiment, the power conductor terminal unit 19 and the optical fiber adapter unit 20 have a protection classification that is lower than the classification of the casing 1 1 .

In an embodiment, the power conductor terminal unit 19 and/or optical fiber adapter unit 20 comprises extra connectors for retrofitting purposes. This enables e.g. to add new power jumpers 14 or optical jumpers 16 to the cable divider 5 without need for adding additional cable dividers in the tower 1 .

In an embodiment, the interior 1 1 comprises extra room, and optionally mounting means, for adding further power conductor terminal units 19 and/or optical fiber adapter units 20 in the cable divider 5. Also this embodiment makes it possible to retrofit the divider, e.g. by adding further power or optical jumpers therein. Furthermore, the extra room may take an extra length of jumpers 14, 16 which may be useful in some cases, e.g. when the dimensions or structure of the tower 1 are not exactly known. The invention is not limited solely to the embodiments described above, but instead many variations are possible within the scope of the inventive concept defined by the claims below. Within the scope of the inventive concept the attributes of different embodiments and applications can be used in conjunction with or replace the attributes of another embodiment or application.

The drawings and the related description are only intended to illustrate the idea of the invention. The invention may vary in detail within the scope of the inventive idea defined in the following claims.

Reference symbols

1 tower

2 equipment room

3 antenna

4 cable arrangement

5 cable divider

6 feeder cable system

7 antenna or RRH level

8 power conductor

9 optical fiber

10 remote radio head (RRH)

1 1 casing

12 feeder cable port

13 power jumper port

14 power jumper

15 optical jumper port

16 optical jumper

17 interior

18 lid

19 power conductor terminal unit

20 optical fiber adapter unit

21 first end of the casing

22 second end of the casing

23 first side of the casing

24 second side of the casing

25 pulling element

26 opening

27 pressure valve

100 cell tower site

Claims

1 . A cable divider, comprising

a casing, comprising

a feeder cable port for receiving a feeder cable system, a power jumper port for receiving a power jumper,

an optical jumper port for receiving an optical jumper, the casing establishing a shielded interior against environmental dust and/or water, the cable divider further comprising

a power conductor terminal unit for connecting a power conductor of a feeder cable system to the power jumper,

an optical fiber adapter unit for connecting an optical fiber of a feeder cable system to a fiber jumper,

said power conductor terminal unit and optical fiber adapter unit being arranged in the interior, and

the casing being arranged to enable the protection classification of the divider higher than the protection classification of the power conductor terminal unit and/or optical fiber adapter unit.

2. The cable divider as claimed in claim 1 , the casing being ar- ranged to enable the liquid ingress protection.

3. The cable divider as claimed in claim 1 or 2, comprising a lid that is repeatedly openable.

4. The cable divider as claimed in any of the preceding claims, comprising at least two optical jumper ports.

5. The cable divider as claimed in any of the preceding claims, comprising at least two power jumper ports.

6. The cable divider as claimed in any of the preceding claims, comprising the feeder cable port in a first end of the casing, the optical jumper port in first side of the casing, and the power jumper port in second side of the casing, opposite to said first side.

7. The cable divider as claimed in any of the preceding claims, comprising a pulling element and dimensioned for a pulling force up to 4000 N.

8. The cable divider as claimed in any of the preceding claims, wherein the feeder cable port is arranged for receiving a hybrid feeder cable.

9. The cable divider as claimed in any of the preceding claims, wherein the power jumper port comprises a cable gland arranged to ground the power jumper(s) arranged in said power jumper port.

10. A cable arrangement, comprising the cable divider as claimed in any of the preceding claims, the cable arrangement further comprising

a feeder cable system arranged in the feeder cable port, a power conductor of the feeder cable system being connected to the power conductor terminal unit, and

an optical fiber of the feeder cable system being connected to the optical fiber adapter unit.

1 1 . The cable arrangement as claimed in claim 10, wherein the power conductor terminal unit and/or the optical fiber adapter unit comprises extra connectors for retrofitting purposes.

12. The cable arrangement as claimed in claim 10 or 1 1 , wherein inside the cable divider, any components are classified for indoor use only.

13. The cable arrangement as claimed in any of the claims 10 - 12, wherein the feeder cable system comprises a hybrid feeder cable, and wherein the hybrid cable has a structure where the optical fiber(s) are surrounded by the power conductor(s).