CN107733522A - L TE-R ring network system - Google Patents
L TE-R ring network system Download PDFInfo
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- CN107733522A CN107733522A CN201710976415.6A CN201710976415A CN107733522A CN 107733522 A CN107733522 A CN 107733522A CN 201710976415 A CN201710976415 A CN 201710976415A CN 107733522 A CN107733522 A CN 107733522A
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- 238000004891 communication Methods 0.000 description 15
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- 230000004048 modification Effects 0.000 description 4
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Classifications
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
- H04B10/27—Arrangements for networking
- H04B10/275—Ring-type networks
- H04B10/2755—Ring-type networks with a headend
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
- H04B10/03—Arrangements for fault recovery
- H04B10/038—Arrangements for fault recovery using bypasses
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- Physics & Mathematics (AREA)
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- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
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- Small-Scale Networks (AREA)
- Optical Communication System (AREA)
Abstract
The invention provides a L TE-R ring network system, which comprises a BBU and a plurality of RRUs connected in series, wherein the BBU is connected with head RRUs and tail RRUs in the plurality of RRUs connected in series to form a loop, and the L TE-R ring network system provided by the invention improves the redundancy performance of the system and greatly improves the reliability.
Description
Technical field
The present invention relates to Railroad Communication System, more particularly to a kind of LTE-R loop-type network systems.
Background technology
At present, annular connected mode is used between GSM-R system base-stations (BTS) and base station controller (BSC), so as to improve
The reliability of wireless subsystem.After GSM-R system evolveds are to LTE-R systems, network tends to flattening, is no longer set in system
Base station controller (BSC), but group in the way of directly being interconnected by base station with the packet-based core networks (EPC) of evolution in a manner of IP
Net, and base station uses distributed form.
The widely used distributed base station of LTE-R systems, distributed base station is by Base Band Unit (BBU) and Remote Radio Unit
(RRU) forming, RRU can be installed in a distributed manner, and this feature brings very big flexibility to engineering construction, meanwhile, in independence
RRU websites can save the corollary equipment facility expense such as transmission, dc source and house.
As shown in figure 1, main between current LTE-R distributed base stations BBU and RRU support star net forming scheme and chain group
Net scheme.Wherein, star net forming scheme is, it is necessary to which fiber resource more than comparison, network reliability are higher;Communication link protection scheme, need
Want less fiber resource, network reliability is minimum.
The content of the invention
In order to solve the problems, such as that current LTE-R networkings reliability is not high, the invention provides a kind of network system to solve
State technical problem.
According to an aspect of the invention, there is provided a kind of LTE-R loop-type network systems,
The loop-type network system includes BBU and the RRU of multiple series connection;
Wherein described BBU is connected with head RRU in the RRU of the multiple series connection and tail RRU, forms loop.
Further, BBU described in the loop-type network system forms one or more ring with the RRU being connected
Road.
Further, take capel RRU and tail RRU is connected on BBU identical baseband boards in the loop network.
Further, take capel RRU and tail RRU is connected on the different baseband boards of BBU in the loop network.
Further, the loop that a BBU and RRU that is connected is formed in the loop network, it is each in each loop
RRU belongs to identical logic district.
Further, when there is Single Point of Faliure with the optical fiber outside BBU junctions in the loop network, breakpoints of optical fiber two
Side RRU belongs to a logic district.
Further, when there is Single Point of Faliure with the optical fiber outside BBU junctions in the loop network, a logic is small
Area splits into two logic districts by boundary of breakpoints of optical fiber.
Further, the loop that a BBU and RRU that is connected is formed in the loop network, it is each in each loop
RRU belongs to different logic districts.
Present invention also offers a kind of LTE-R loop-type network systems, the loop-type network system includes BBU and single RRU;
Wherein described BBU is connected with two ports of the RRU, forms loop.
The invention provides a kind of LTE-R loop-type network systems, the redundancy performance of system is being improved, and its reliability obtains
Larger raising.
Brief description of the drawings
In order to illustrate more clearly about the embodiment of the present invention or technical scheme of the prior art, below will be to embodiment or existing
There is the required accompanying drawing used in technology description to be briefly described, it should be apparent that, drawings in the following description are this hairs
Some bright embodiments, for those of ordinary skill in the art, on the premise of not paying creative work, can be with root
Other accompanying drawings are obtained according to these accompanying drawings.
Fig. 1 shows star in the prior art and communication link protection schematic diagram;
Fig. 2 shows annular networking schematic diagram 1 according to embodiments of the present invention;
Fig. 3 shows annular networking schematic diagram 2 according to embodiments of the present invention;
Fig. 4 shows annular networking schematic diagram 3 according to embodiments of the present invention;
Fig. 5 shows annular networking schematic diagram 4 according to embodiments of the present invention;
Embodiment
To make the purpose, technical scheme and advantage of the embodiment of the present invention clearer, below in conjunction with the embodiment of the present invention
In accompanying drawing, the technical scheme in the embodiment of the present invention is clearly and completely illustrated, it is clear that described embodiment is
Part of the embodiment of the present invention, rather than whole embodiments.Based on the embodiment in the present invention, those of ordinary skill in the art
The every other embodiment obtained under the premise of creative work is not made, belongs to the scope of protection of the invention.
LTE-R systems include core net and wireless access network, and wherein wireless access network includes eNodeB, and eNodeB is used
Distributed structure/architecture, is a kind of distributed base station, it realizes that IP is connected with evolution block core net (EPC).ENodeB is provided
Wireless coverage in LTE-R network ranges.ENodeB includes Base Band Unit (BBU) and Remote Radio Unit (RRU).Wherein BBU
It is main to complete the functions such as base band signal process, protocol conversion and scheduling of resource, and pass through the core where S1 interfaces and MME/S-GW
Heart net carries out data interaction;Multiple RRU provide the wireless coverage of LTE-R networks, and different BBU forms different logic districts,
Access and the transmission of radio links function of user equipment are completed by Uu interfaces.RRU passes through CPRI (wireless universal common interface)
BBU is connected to using optical fiber, cable length is up to 10km (km), in the case where CPRI interfaces configure high-power smooth power amplifier,
Cable length is highly suitable for the networking wiring of Along Railway up to 40km.RRU, in Along Railway both sides, protects in zonal distribution
The wireless coverage to railway is held, realizes the communication with train.
One BBU of embodiment and multiple RRU form a loop, are connected in loop between RRU by optical fiber, RRU with
BBU is connected by CPRI interfaces.Embodiment with a set of 6 sets of RRU of BBU bands, form it is illustrative exemplified by 2 loops, but
It is not limited to a set of BBU only 6 sets of RRU of band and forms 2 loops, 1 loop is formed for 1 set of a set of BBU bands and above RRU, or
7 sets of a set of BBU bands and above RRU form 2 and above loop may be applicable to the present invention.
Multiple RRU are sequentially arranged on Along Railway:First RRU1, the 2nd RRU2, the 3rd RRU3, the 4th RRU4, the 5th
RRU5, the 6th RRU6;A BBU is arranged simultaneously;The BBU and the first RRU1 being connected in series, the 2nd RRU2, the 3rd RRU3 groups
Into first loop, the BBU also forms second loop with the 4th RRU4, the 5th RRU5, the 6th RRU6 being connected in series.
There are two ports of input and output in each RRU, the level between RRU is realized by these inputs and delivery outlet
Connection.As the head RRU being connected in series, i.e. RRU1 one end (not cascading end) and conduct during RRU is mutually cascaded as shown in figures 2 and 3
The tail RRU being connected in series, i.e. RRU3 one end (not cascading end) are free end;As the head RRU being connected in series, i.e., the one of RRU4
Hold (not cascading end) and as the tail RRU being connected in series, i.e., RRU6 one end (not cascading end) is free end, and free end is connected to
CPRI optical ports in the BBU, middle RRU2 input port and output port respectively the output port with RRU1, RRU3 it is defeated
Inbound port connects, and the output port with RRU4, RRU6 input port connect respectively for middle RRU5 input port and output port
Connect, so as to realize annular networking.
When any one place's optical fiber Single Point of Faliures of label 1-8, breakpoint one or both sides RRU can be by not breaking down one
The optical fiber of side carries out data transmission with BBU, does not influence RRU transmission signals, carries out wireless coverage, and then ensures that the network provides
Normal communication service.
As shown in Fig. 22 loops, the take capel RRU (RRU1 of each loop are formed between the RRU and the BBU of BBU connections
And RRU4) and ring tail RRU (RRU3 and RRU6) be all connected on one piece of baseband board, when baseband board normal work, BBU and RRU
Between the optical fiber that connects when Single Point of Faliure occurs, do not influence the data transfer between RRU and BBU, network can provide normal logical
Communication service, once but baseband board break down, then the railway section that RRU1 to RR6 is covered will lose wireless signal covering, make
Into the coverage hole of large area, influence network and normal communication service is provided.
More star-like networking and communication link protection improve reliability to Fig. 2 to a certain extent, but still suffer from weak link.In order to
The reliability of network is further improved, the present invention proposes the network system shown in Fig. 3, as shown in figure 3, configuring two pieces for BBU
Baseband board:Baseband board 1 and baseband board 2, take capel RRU (RRU1 and RRU4) the connection baseband boards 1 of each loop, ring tail RRU (RRU3
And RRU6) connection baseband board 2, when baseband board 1 or baseband board 2 break down, RRU still can pass through ring tail or take capel and institute
State BBU to carry out data transmission, do not influence network and normal communication service is provided.
The loop that loop network shown in Fig. 2 and Fig. 3, BBU and the RRU that is connected are formed, each RRU in each loop can
To belong to identical logic district, when there is Single Point of Faliure with the optical fiber outside BBU junctions in the loop network, optical fiber breaks
Point both sides RRU may belong to a logic district, can also belong to different logic districts.Formed with RRU1, RRU2 and RRU3
Loop exemplified by, when optical fiber Single Point of Faliure occurring at label 2, RRU1, RRU2 and RRU3 annular networking become communication link protection, one
Individual chain includes RRU1, and another chain includes RRU2 and RRU3, and the two chains may belong to identical logic district, can also belong to
Different logic districts;When Single Point of Faliure occurring at label 3, RRU1, RRU2 and RRU3 annular networking become communication link protection, and one
Individual chain includes RRU1 and RRU2, and another chain includes RRU3, and the two chains may belong to identical logic district, can also belong to
Different logic districts.
The loop that loop network shown in Fig. 2 and Fig. 3, BBU and the RRU that is connected are formed, each RRU in each loop
It may belong to different logic districts.
Loop network shown in Fig. 4 and Fig. 5, BBU are connected to form loop with single RRU two ports.
Loop network shown in Fig. 4 and Fig. 5, when any one place's optical fiber Single Point of Faliures of label 1-2, RRU can be by not
Break down the optical fiber of side and BBU carries out data transmission, do not influence RRU transmission signals, carry out wireless coverage, and then ensure institute
State network and normal communication service is provided.
As shown in figure 4, RRU two ports are connected on BBU one piece of baseband board, and when baseband board normal work, BBU
When Single Point of Faliure occurs for the optical fiber being connected between RRU, the data transfer between RRU and BBU is not influenceed, network can provide normally
Communication service, once but baseband board break down, then RRU covering railway section will lose wireless signal covering, cause
Coverage hole, influence network and normal communication service is provided.
As shown in figure 5, configure two pieces of baseband boards for BBU:Baseband board 1 and baseband board 2, RRU a port linker band
Plate 1, another port connection baseband board 2, when baseband board 1 or baseband board 2 break down, RRU still can pass through two ends
A port in mouthful carries out data transmission with the BBU, does not influence network and provides normal communication service.
It should be noted that:The above embodiments are merely illustrative of the technical solutions of the present invention, rather than its limitations.In system
Each equipment between not necessarily meaning be a kind of directly electrical connection, what specification represented is only logical relation.To the greatest extent
The present invention is described in detail with reference to the foregoing embodiments for pipe, it will be understood by those within the art that:It is still
Technical scheme described in foregoing embodiments can be modified, or which part technical characteristic is equally replaced
Change;And these modifications or replacement, the essence of appropriate technical solution is departed from the essence of various embodiments of the present invention technical scheme
God and scope.
Obviously, those skilled in the art can carry out the essence of various changes and modification without departing from the present invention to the present invention
God and scope.So, if these modifications and variations of the present invention belong to the scope of the claims in the present invention and its equivalent technologies
Within, then the present invention is also intended to comprising including these changes and modification.
Claims (9)
- A kind of 1. LTE-R loop-type network systems, it is characterised in thatThe loop-type network system includes BBU and the RRU of multiple series connection;Wherein described BBU is connected with head RRU in the RRU of the multiple series connection and tail RRU, forms loop.
- 2. LTE-R loop-type network systems according to claim 1, it is characterised in thatBBU described in the loop-type network system forms one or more loop with the RRU being connected.
- 3. LTE-R loop-type network systems according to claim 1, it is characterised in thatHead RRU and tail RRU is connected on BBU identical baseband boards in the loop network.
- 4. LTE-R loop-type network systems according to claim 1, it is characterised in thatHead RRU and tail RRU is connected on the different baseband boards of BBU in the loop network.
- 5. LTE-R loop-type network systems according to claim 1, it is characterised in thatThe loop that a BBU and RRU that is connected is formed in the loop network, each RRU in each loop belong to identical Logic district.
- 6. LTE-R loop-type network systems according to claim 5, it is characterised in thatWhen there is Single Point of Faliure with the optical fiber outside BBU junctions in the loop network, breakpoints of optical fiber both sides RRU belongs to one Logic district.
- 7. LTE-R loop-type network systems according to claim 5, it is characterised in thatWhen there is Single Point of Faliure with the optical fiber outside BBU junctions in the loop network, a logic district is with breakpoints of optical fiber Two logic districts are split into for boundary.
- 8. LTE-R loop-type network systems according to claim 1, it is characterised in thatThe loop that a BBU and RRU that is connected is formed in the loop network, each RRU in each loop belong to different Logic district.
- A kind of 9. LTE-R loop-type network systems, it is characterised in thatThe loop-type network system includes BBU and single RRU;Wherein described BBU is connected with two ports of the RRU, forms loop.
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Cited By (1)
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CN110855541A (en) * | 2019-10-31 | 2020-02-28 | 中盈优创资讯科技有限公司 | Ring splitting method and device for ring network equipment |
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Effective date of registration: 20220124 Address after: 100070 block B, yard 1, South Road, Automobile Museum, Fengtai Science Park, Fengtai District, Beijing Patentee after: CRSC RESEARCH & DESIGN INSTITUTE GROUP Co.,Ltd. Patentee after: Tonghao Innovation Investment Group Co.,Ltd. Address before: China Communications Building, No.1 yard, Nanli, Fengtai Science and Technology Park, Fengtai District, Beijing 100070 Patentee before: CRSC RESEARCH & DESIGN INSTITUTE GROUP Co.,Ltd. |