CN103326783A

CN103326783A - Signal transmission method, relevant equipment and signal transmission system

Info

Publication number: CN103326783A
Application number: CN2012100817117A
Authority: CN
Inventors: 齐江; ***
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2012-03-23
Filing date: 2012-03-23
Publication date: 2013-09-25
Anticipated expiration: 2032-03-23
Also published as: CN103326783B

Abstract

The invention discloses a signal transmission method, relevant equipment and a signal transmission system in order to achieve signal transmission between RECs and REs and solve the problems that an existing link for the signal transmission between the RECs and the REs needs a large number of optical fibers and is high in engineering constructing cost, and mutual interference among all the REs can not be caused. One method includes the steps that the RECs broadcast downlink signals to a beam splitter to make the beam splitter broadcast the downlink signals to the REs, the RECs are connected with the beam splitter through optical fibers, the beam splitter is independently connected with all the REs through optical fibers, the downlink signals comprise a plurality of downlink sub-signals, each downlink sub-signal carries downlink identification, the downlink identification is used for indicating which RE each downlink sub-signal belongs to, clocks of the REs keep synchronization with clocks of the RECs, and each RE receives the downlink sub-signal belonging to the RE from the downlink sub-signals through the optical fibers connected between the beam splitter and with the RE according to the downlink identification.

Description

A kind of method for transmitting signals and relevant device and signal transmission system

Technical field

The present invention relates to communication technical field, relate in particular to a kind of method for transmitting signals and relevant device and signal transmission system.

Background technology

Distributed base station is just becoming the prevailing model of base station equipment at present, baseband processing unit (BBU, BaseBand Unit) and between the Remote Radio Unit (RRU, Remote Radio Unit) connect by optical fiber, a BBU can support a plurality of RRU.Distribution-type base station architecture has the characteristics such as volume is little, low in energy consumption, flexible for installation, rapid deployment, can satisfy the application demand of different capabilities, different scenes.

In the present various standard wireless network, BBU is different with the Optical Fiber Transmission interface standard between the RRU, that occupy main flow is common public radio interface (CPRI, Common Public Radio Interface) standard, also exist with CPRI and similarly open base band radio frequency interface (OBRI/IR, Open BBU RRHInterface/Interface between the RRU and the BBU) standard, its basic principle is similar with CPRI.RRU is a kind of wireless device (RE, Radio Equipment), usually is installed in outdoor, lessly need device upgrade, BBU is a kind of radio equipment controller (REC, Radio EquipmentControl), its complex structure, need to frequently carry out software upgrading and real-time servicing, dispose at far-end by RE, can concentrate in together REC and manage, can effectively reduce wireless O﹠M difficulty, simplify the requirement of wireless site, meet operator and concentrate the networking requirement of disposing.

Under the transmission of the long-distance optical fiber more than the 20km, there is the multiple network topological structure between REC and the RE, connect such as point to point connect, chain connection, annular etc.Describe as an example of the CPRI standard example, see also shown in Figure 1ly, in point to point connect, a REC can support a RE, is connected by optical fiber between REC and the RE; In chain connected, a REC can support a plurality of RE (it is respectively RE1 and RE2 that two RE have been shown among Fig. 1), was connected by optical fiber between REC and the RE1, was connected by optical fiber between RE1 and the RE2; In annular connected, a REC can support a plurality of RE (it is respectively RE3 and RE4 that two RE have been shown among Fig. 1), was connected by optical fiber between REC and the RE3, was connected by optical fiber between RE3 and the RE4, was connected by optical fiber between RE4 and the REC.

The present inventor finds that there is following defective at least in prior art: although REC supports the multiple network topological structure with optical fiber link between the RE, REC with between the RE that directly links to each other or RE with all only supporting point-to-point optical fiber to connect between the RE.In the situation that REC/RE is with transmitting by long-distance optical fiber between the RE, for existing point to point connect, because each RE separately and consist of point-to-point connection between the REC, when the quantity of RE is more, need multifiber independent carry out point-to-point the connection with REC, the number of fibers that needs is large, and project cost is high; Connect for existing chain, although a REC has supported a plurality of RE, but RE still consists of point-to-point connection between the independent and REC, being connected between RE and the RE also is independent point-to-point connection, point to point connect with respect to the RE that forms equal number can be saved number of fibers, reduce project cost, but when middle RE breaks down, can cause the communication service between all RE of downstream and the REC to be interrupted, affect the normal operation of this operation system, and when network upgrade need to increase RE, need to take whole chain connecting link apart, this must need the proper communication of the RE on the broken link professional; For existing annular the connection, owing to going back pattern of wants annular networking between REC and the RE, with respect to the chain connection of the RE that forms equal number, its number of fibers that needs need to double, and the number of fibers that needs is large, and project cost is high.

Summary of the invention

The embodiment of the invention provides a kind of method for transmitting signals and relevant device and signal transmission system, be used for realizing signal transmission between REC and the RE, solving existing REC needs the problem that number of fibers is large, project cost is high with the link of signal transmission between the RE, and can not cause the phase mutual interference between each RE.

On the one hand, a kind of method for transmitting signals that the embodiment of the invention provides comprises:

Radio equipment controller REC broadcast downstream signal is to beam splitter, so that described beam splitter is broadcasted described downstream signal to a plurality of wireless device RE, be connected by optical fiber between described radio equipment controller and the described beam splitter, described beam splitter is connected separately with each wireless device by optical fiber respectively, described downstream signal includes a plurality of descending subsignals, each descending subsignal carries a lower line identifier, described lower line identifier is used for descending subsignal of expression and belongs to which wireless device, and the clock of described a plurality of wireless devices is synchronous with the clock maintenance of described radio equipment controller respectively;

Described each wireless device respectively by described beam splitter with oneself between the optical fiber that is connected, from described downstream signal, receive one's own descending subsignal according to described lower line identifier.

On the other hand, the another kind of method for transmitting signals that the embodiment of the invention provides comprises:

Beam splitter receives the downstream signal of radio equipment controller REC broadcasting, be connected by optical fiber between described radio equipment controller and the described beam splitter, described downstream signal includes a plurality of descending subsignals, each descending subsignal carries a lower line identifier, and described lower line identifier is used for descending subsignal of expression and belongs to which wireless device RE;

Described beam splitter is to the described downstream signal of a plurality of broadcast by wireless devices, so that described a plurality of wireless device receives respectively one's own descending subsignal according to described lower line identifier from described downstream signal, described beam splitter is connected separately with each wireless device by optical fiber respectively, and the clock of described a plurality of wireless devices is synchronous with the clock maintenance of described radio equipment controller respectively.

Each wireless device RE respectively by beam splitter with own between the optical fiber that is connected each up subsignal is sent to described beam splitter, so that described beam splitter is transferred to radio equipment controller REC with described each up subsignal, be connected by optical fiber between described radio equipment controller and the described beam splitter, described beam splitter is connected separately with each wireless device by optical fiber respectively, each up subsignal carries a upper line identifier and a physical layer bursts expense, it is which wireless device sends that described upper line identifier is used for up subsignal of expression, and the clock that described physical layer bursts expense is used for realizing described each wireless device is synchronous with the clock of described radio equipment controller;

Described radio equipment controller receives each up subsignal that described beam splitter is transmitted by the optical fiber that is connected between described beam splitter and the described radio equipment controller.

Beam splitter receives each up subsignal that each wireless device RE sends respectively, described beam splitter is connected separately with each wireless device by optical fiber respectively, each up subsignal carries a upper line identifier and a physical layer bursts expense, it is which wireless device sends that described upper line identifier is used for up subsignal of expression, and the clock that described physical layer bursts expense is used for realizing each wireless device is synchronous with the clock of described radio equipment controller;

Described beam splitter is transferred to radio equipment controller REC with described each up subsignal, is connected by optical fiber between described radio equipment controller and the described beam splitter.

On the other hand, the signal transmission apparatus that the embodiment of the invention provides comprises:

Radio equipment controller REC, a plurality of wireless device RE, wherein,

Be connected by optical fiber between described radio equipment controller and the beam splitter, described beam splitter is connected separately with each wireless device by optical fiber respectively;

Described radio equipment controller comprises: downlink broadcast unit, uplink receiving unit, and each wireless device comprises respectively: descending receiving element, up transmitting element, wherein,

Described downlink broadcast unit, be used for the broadcast downstream signal to described beam splitter, so that described beam splitter is to the described downstream signal of a plurality of broadcast by wireless devices, described downstream signal includes a plurality of descending subsignals, each descending subsignal carries a lower line identifier, described lower line identifier is used for descending subsignal of expression and belongs to which wireless device, and the clock of described a plurality of wireless devices is synchronous with the clock maintenance of described radio equipment controller respectively;

Each descending receiving element is respectively applied to the optical fiber by being connected between described each wireless device and the described beam splitter, receives one's own descending subsignal according to described lower line identifier from described downstream signal;

Each up transmitting element, be respectively applied to by the optical fiber that is connected between described each wireless device and the described beam splitter each up subsignal be sent to described beam splitter, so that described beam splitter is transferred to described radio equipment controller with described each up subsignal, each up subsignal carries a upper line identifier and a physical layer bursts expense, it is which wireless device sends that described upper line identifier is used for up subsignal of expression, and the clock that described physical layer bursts expense is used for realizing each wireless device is synchronous with the clock of described radio equipment controller;

The uplink receiving unit is used for receiving by the optical fiber that is connected between described beam splitter and the described radio equipment controller each up subsignal of described beam splitter forwarding.

On the other hand, the beam splitter that the embodiment of the invention provides comprises:

The first receiving element, be used for receiving the downstream signal of radio equipment controller REC broadcasting, be connected by optical fiber between described radio equipment controller and the described beam splitter, described downstream signal includes a plurality of descending subsignals, each descending subsignal carries a lower line identifier, and described lower line identifier is used for descending subsignal of expression and belongs to which wireless device RE;

The first transmission unit, be used for to the described downstream signal of a plurality of broadcast by wireless devices, so that described a plurality of wireless device receives respectively one's own descending subsignal according to described lower line identifier from described downstream signal, described beam splitter is connected separately with each wireless device by optical fiber respectively, and the clock of described a plurality of wireless devices is synchronous with the clock maintenance of described radio equipment controller respectively;

The second receiving element, be used for receiving each up subsignal that each wireless device sends respectively, each up subsignal carries a upper line identifier and a physical layer bursts expense, it is which wireless device sends that described upper line identifier is used for up subsignal of expression, and the clock that described physical layer bursts expense is used for realizing each wireless device is synchronous with the clock of described radio equipment controller;

The second transmission unit is used for described each up subsignal is transferred to radio equipment controller.

On the other hand, the signal transmission system that the embodiment of the invention provides comprises: foregoing signal transmission apparatus and foregoing beam splitter.

As can be seen from the above technical solutions, the embodiment of the invention has the following advantages:

In an embodiment provided by the invention, radio equipment controller is connected with beam splitter by optical fiber, beam splitter is connected separately with each wireless device by optical fiber respectively, radio equipment controller broadcast downstream signal is to beam splitter, then beam splitter will be by the optical fiber that is connected between beam splitter and the radio equipment controller to this downstream signal of a plurality of broadcast by wireless devices, thereby has realized that by beam splitter radio equipment controller is to each wireless device transmission of downlink signal.Because radio equipment controller is connected with beam splitter by optical fiber, beam splitter is connected separately with a plurality of wireless devices by optical fiber respectively again, can save a large amount of optical fiber than the point to point connect of prior art, annular connection, and project cost is low; Chain than prior art connects, because each wireless device all is connected with beam splitter by optical fiber respectively, can the phase mutual interference between each wireless device, when one of them wireless device breaks down or network upgrade need to increase wireless device the time, the proper communication that can not have influence between other wireless device and the radio equipment controller is professional; The signal transmission form that the embodiment of the invention adopts meets the existing network deployment scenario of present radio equipment controller and wireless device, has good compatibility.

Description of drawings

In order to be illustrated more clearly in the technical scheme in the embodiment of the invention, the accompanying drawing of required use was done to introduce simply during the below will describe embodiment, apparently, accompanying drawing in the following describes only is some embodiments of the present invention, to those skilled in the art, can also obtain according to these accompanying drawings other accompanying drawing.

Fig. 1 is three kinds of network topology structure schematic diagrames between REC and the RE in the prior art;

Fig. 2 is an embodiment schematic diagram of method for transmitting signals provided by the invention;

Fig. 3 is a networking structure schematic diagram between REC provided by the invention and the RE;

Fig. 4 is the schematic diagram of another networking structure between REC provided by the invention and the RE;

Fig. 5 is the frame structure schematic diagram of downstream signal provided by the invention;

Fig. 6 is another embodiment schematic diagram of method for transmitting signals provided by the invention;

Fig. 7 is the frame structure schematic diagram of upward signal provided by the invention;

Fig. 8 is the embodiment schematic diagram of signal transmission apparatus provided by the invention;

Fig. 9 is the embodiment schematic diagram of beam splitter provided by the invention;

Figure 10 is the embodiment schematic diagram of signal transmission system provided by the invention;

Figure 11 is interaction flow schematic diagram between each included unit of signal transmission system provided by the invention.

Embodiment

For so that goal of the invention of the present invention, feature, advantage can be more obvious and understandable, below in conjunction with the accompanying drawing in the embodiment of the invention, technical scheme in the embodiment of the invention is clearly and completely described, obviously, the embodiments described below only are the present invention's part embodiment, but not whole embodiment.Based on the embodiment among the present invention, the every other embodiment that those skilled in the art obtains belongs to the scope of protection of the invention.

A kind of method for transmitting signals that the embodiment of the invention provides as shown in Figure 2, comprising:

201, radio equipment controller broadcast downstream signal is to beam splitter.

Wherein, be connected by optical fiber between radio equipment controller and the beam splitter, beam splitter is connected separately with each wireless device by optical fiber respectively, downstream signal includes a plurality of descending subsignals, each descending subsignal carries a lower line identifier, lower line identifier is used for descending subsignal of expression and belongs to which wireless device, and the clock of a plurality of wireless devices is synchronous with the clock maintenance of radio equipment controller respectively.

The networking structure of the signal transmission system that the embodiment of the invention provides is point-to-multipoint (PtMP, Pointto Multipoint) optical fiber connects, be that radio equipment controller is connected with beam splitter by optical fiber, beam splitter is connected with at least two wireless devices by different optical fiber respectively.For the beam splitter that the embodiment of the invention provides, a kind of implementation is that beam splitter can be the passive light power splitter, wherein, the passive light power splitter is a kind of passive optical fiber devices, the reliability of beam splitter is equal to optical fiber link, only introduce the certain power decay for the light signal of transmission, in the network of optical fiber access (FTTx, Fiber-To-The-x), extensive application is arranged.The splitting ratio of beam splitter is 1: 64, the branch optical fiber that is connected between beam splitter and the wireless device can reach more than 20 kms (km), the trunk optical fiber that is connected between beam splitter and the radio equipment controller can reach more than the 20km, arbitrarily cascade of beam splitter, as long as guarantee in the situation of total optical power budget and splitting ratio, can distribute according to the physical site of RE reality and draw arbitrarily branch optical fiber, engineering construction is convenient.

As shown in Figure 3, in a signal transmission system, radio equipment controller (hereinafter to be referred as REC) is connected with beam splitter by an optical fiber (for example optical fiber 0), beam splitter is connected with each wireless device (for example RE1, RE2, RE3) respectively by three light (for example optical fiber 1, optical fiber 2, optical fiber 3), in embodiments of the present invention, realized that by beam splitter the signal between RE1, RE2, RE3 and the REC transmits.

If the point-to-point interconnection according to prior art, realize RE1, RE2, RE3 respectively with REC between be connected, the optical fiber that needs adds up to three optical fiber 0, an optical fiber 1, an optical fiber 2, an optical fiber 3, and the optical fiber that needs in the embodiment of the invention adds up to an optical fiber 0, an optical fiber 1, an optical fiber 2, an optical fiber 3, as seen the networking mode that provides of the embodiment of the invention can be saved optical fiber, reduce project cost, under normal conditions, each RE at a distance of between distance not far, the length of optical fiber 1 and light 2 and optical fiber 3 is all shorter, and the length of optical fiber mainly is that optical fiber 0 is longer.

If connect according to the chain among prior art such as Fig. 1, REC directly is connected with RE1, RE1 is connected with RE2, RE2 is connected with RE3 again, the point to point connect of the RE that existing chain connected mode is identical with respect to quantity can be saved number of fibers, reduce project cost, but when middle RE1 or RE2 break down, can cause the communication service between all RE of downstream and the REC to be interrupted, affect the normal operation of whole operation system, and when network upgrade need to increase RE, need to take whole chain connecting link apart, the proper communication of the RE on the meeting broken link is professional.And the method for transmitting signals that the embodiment of the invention proposes, when RE1 or RE2 or RE3 break down, proper communication business between other RE and the REC can not be affected, when network upgrade need to increase wireless device, only the wireless device that newly increases directly need to be cascaded on the beam splitter and get final product, also can not have influence on the proper communication business between original wireless device and the REC.

If connect according to the annular of prior art and since REC and RE1, RE2, RE3 by optical fiber finish be connected after, need RE3 to be connected to form again ring network with REC.The networking mode that the embodiment of the invention proposes only needs an optical fiber that REC and beam splitter are coupled together, and then respectively RE1, RE2, RE3 is connected on the beam splitter, and networking mode provided by the invention can be saved optical fiber, reduces project cost.

Need to prove, in embodiments of the present invention, arbitrarily cascade of beam splitter, as long as guarantee in the situation of total optical power budget and splitting ratio, can distribute according to the physical site of RE reality and draw arbitrarily branch optical fiber, engineering construction is convenient, as shown in Figure 4, REC is connected with beam splitter 1 by optical fiber 0, beam splitter 1 is connected with beam splitter 2 by optical fiber 4, beam splitter 1 is connected with RE1, RE2, RE3 respectively by optical fiber 1, optical fiber 2, optical fiber 3, and beam splitter 2 is connected with RE4, RE5 respectively by optical fiber 5, optical fiber 6.Certainly, Fig. 4 is a kind of legend that illustrates that beam splitter can cascade, the situation that can also dispose according to concrete application scenarios in actual applications a plurality of beam splitter cascades, and restriction is not done in just explanation herein.

In embodiments of the present invention, a kind of feasible implementation is, radio equipment controller is with time division multiplexing (TDM, Time Division Multiplex) broadcast downstream signal, radio equipment controller includes a plurality of descending subsignals in downstream signal, each descending subsignal carries a lower line identifier, and lower line identifier is used for descending subsignal of expression and belongs to which wireless device.Each wireless device receives only one's own descending subsignal according to the lower line identifier of each descending subsignal in the downstream signal.For example, as shown in Figure 3, if the descending subsignal in the downstream signal of REC broadcasting carries the sign of RE1, represent that then this descending subsignal sends to RE1, if can judging, the sign of the RE1 that RE2 carries according to the descending subsignal in this downstream signal learns that this descending subsignal is not to send to oneself, will abandon this downstream signal.

In actual applications, describe as an example of REC employing CPRI standard example, REC is connected with beam splitter by optical fiber, beam splitter has connected RE1 by different optical fiber respectively, RE2, ..., RE63 is totally 63 RE, the frame structure of the downstream signal of REC broadcasting sees also shown in Figure 5, the frame structure schematic diagram of the downstream signal that Fig. 5 provides for the embodiment of the invention, wherein, basic frame number (BFN, Basic FrameNumber) is the frame of CPRI standard, frame length is 10ms, and the BFN of 10ms comprises altogether and is respectively RE1, ..., REn, ..., Hyperframe (Hyperframe) and PtMP control frame that RE63 distributes.Hyperframe be respectively #0 ..., #Z ..., #M, increase the expense (overhead) of several bytes on the structure of each Hyperframe, Identity Code (the ID that all comprises respectively each RE in the expense, IDentity) as the sign, the payload of each Hyperframe (payload) also comprise 256 basic frames (basic frame) be respectively #0 ..., #x ..., #255.Comprise also on the structure of PtMP control frame that the ID of each RE is as sign, the PtMP control frame refers to the physical layer control information that PtMP needs, the RE quantity that can connect according to a REC is no more than 128 calculating, 7bit RE ID can identify all RE quantity, the expense that increases by 1 byte namely can identify different RE, wherein highest order shows the control information of carrying PtMP for the RE ID of " 1 " represents broadcast message, and all RE will receive.According to existing CPRI standard, the Hyperframe quantity of supporting in the 10ms is 150, owing to having increased RE ID expense and PtMP control frame before each RE, is less than 149 therefore be total to M the Hyperframe of supporting in the embodiment of the invention.Certainly, along with the evolution of standard and the development of technology, the quantity of the Hyperframe of support can have other variations, describes as example at this, does not do restriction.

In actual applications; PtMP CPRI interface need to carry out HardwareUpgring at existing CPRI interface; for fear of repeated construction waste resource; can be on the hardware device of original REC and RE; the PtMPCPRI interface function is integrated in the pluggable CPRI optical module; provide compatible original hardware interface to REC, RE, can protect so existing REC, RE hardware investment, only need to change the CPRI optical module and namely can upgrade to the PtMP networking.

Need to prove, in the prior art, no matter point to point connect or chain connect or annular connects, the downstream signal that REC sends to RE is not carry sign, the embodiment of the invention represents to send to the descending subsignal of each wireless device with the sign of wireless device by time-multiplexed mode, beam splitter can receive the downstream signal of radio equipment controller broadcasting by the optical fiber that is connected between beam splitter and the radio equipment controller.

Need to prove, the wireless device in the embodiment of the invention specifically can be Remote Radio Unit (RRU, Remote Radio Unit), and RRU is installed in outdoor usually, lessly needs device upgrade.Radio equipment controller in the embodiment of the invention specifically can be baseband processing unit (BBU, Base BandUnit), the complex structure of BBU, need to frequently carry out software upgrading and real-time servicing, dispose at far-end by RE, can concentrate in together REC and manage, can effectively reduce wireless O﹠M difficulty, simplify the requirement of wireless site, meet operator and concentrate the networking requirement of disposing.

In addition, in embodiments of the present invention, the clock of each wireless device is synchronous with the clock maintenance of radio equipment controller respectively, and owing to each wireless device is connected with beam splitter by different optical fiber respectively, therefore each wireless device is separate, its clock separately can be separate.

202, each wireless device respectively by beam splitter with own between the optical fiber that is connected, from downstream signal, receive one's own descending subsignal according to lower line identifier.

In embodiments of the present invention, beam splitter is after radio equipment controller receives downstream signal, beam splitter by with each wireless device between the optical fiber that is connected downstream signal is transferred to each wireless device, can be transferred to each wireless device with the downstream signal of realizing radio equipment controller broadcasting, because a plurality of descending subsignal that downstream signal comprises carries lower line identifier, each wireless device can receive only one's own descending subsignal according to this time line identifier.

As shown in Figure 3, if the descending subsignal that the downstream signal of REC broadcasting comprises carries lower line identifier RE1, represent that then this descending subsignal sends to RE1, after beam splitter receives this downstream signal from REC, respectively by optical fiber 1, optical fiber 2, optical fiber 3 is transferred to RE1 with downstream signal, RE2, RE3, RE1 finds by lower line identifier RE1 this descending sign represents it is one's own descending subsignal, then RE1 receives this descending subsignal, RE2 and RE3 can judge according to this time line identifier RE1 and learn that this descending subsignal is not to send to oneself, will abandon this downstream signal.

Need to prove, in order to guarantee the radio open performance requirement, need to guarantee the time delay symmetry between REC and the RE, for example, global system for mobile communications (GSM, Global System of Mobilecommunication) requires the propagation delay time of signal between REC and the RE to require less than 1ms.In the step 202, beam splitter by beam splitter respectively with each wireless device between the optical fiber that is connected downstream signal is transferred to respectively after each wireless device, can also comprise the steps: that each wireless device calculates respectively propagation delay time according to the one's own descending subsignal that receives, propagation delay time is used for revising up subsignal when each wireless device when radio equipment controller sends up subsignal, and is identical with the transmitted in both directions time delay between the radio equipment controller to guarantee each wireless device.Wireless device is after beam splitter receives downstream signal, because the clock of wireless device and radio equipment controller keeps synchronously, then wireless device can deduct the transmitting time point that records with the time point that receives downstream signal from downstream signal, obtains radio equipment controller and sends the propagation delay time that downstream signal produces.

Need to prove, the method for transmitting signals that the embodiment of the invention provides can also comprise: radio equipment controller is opened ranging window, with realization the wireless device that is subordinated to radio equipment controller is opened when standing or breaking down and is found range.In order to allow the RE of different distance when opening the station, can automatically realize accessing REC, radio equipment controller need to be opened ranging window, the transmission of upward signal need to stop during range finding, network radius for 2km, if the time that needs 2 frames is finished in range finding, then the transmission of upward signal approximately need to stop 200 microseconds (us), and the time that certain in actual applications upward signal stops to transmit is determined by concrete networking structure, only explain herein, do not do restriction.In wireless traffic is used, just need again to find range owing to only having RE to open when station or RE break down, range finding mechanism is set to be needed RE to send fault or is triggered by webmaster just to open ranging window, finds range for normal RE service impact to reduce.When again finding range for the RE of fault, owing to storing original ranging information, therefore can shorten ranging window, do not affect other RE operation.

In embodiment provided by the invention, radio equipment controller is connected with beam splitter by optical fiber, beam splitter is connected separately with each wireless device by optical fiber respectively, radio equipment controller broadcast downstream signal is to beam splitter, then beam splitter will be by the optical fiber that is connected between beam splitter and the radio equipment controller to this downstream signal of a plurality of broadcast by wireless devices, thereby has realized that by beam splitter radio equipment controller is to each wireless device transmission of downlink signal.Since radio equipment controller by optical fiber be connected with beam splitter, beam splitter is connected separately with a plurality of wireless devices by optical fiber respectively again, can save a large amount of optical fiber than the point to point connect of prior art, annular connection, project cost is low; Chain than prior art connects, because each wireless device all is connected with beam splitter by optical fiber respectively, can the phase mutual interference between each wireless device, when one of them wireless device breaks down or network upgrade need to increase wireless device the time, the proper communication that can not have influence between other wireless device and the radio equipment controller is professional; The signal transmission form that the embodiment of the invention adopts meets the existing network deployment scenario of present radio equipment controller and wireless device, has good compatibility.

Above embodiment has introduced the method for transmitting signals that the embodiment of the invention provides, next introduce the method for transmitting signals corresponding to previous embodiment, different from embodiment shown in Figure 2, the method for transmitting signals that is based on radio equipment controller and wireless device realization that Fig. 2 describes, next a kind of method for transmitting signals that is based on the beam splitter realization of describing comprises:

Beam splitter receives the downstream signal of radio equipment controller broadcasting, be connected by optical fiber between radio equipment controller and the beam splitter, downstream signal includes a plurality of descending subsignals, each descending subsignal carries a lower line identifier, and lower line identifier is used for descending subsignal of expression and belongs to which wireless device;

Beam splitter is to a plurality of broadcast by wireless devices downstream signals, so that a plurality of wireless devices receive respectively one's own descending subsignal according to lower line identifier from downstream signal, beam splitter is connected separately with each wireless device by optical fiber respectively, and the clock of a plurality of wireless devices is synchronous with the clock maintenance of radio equipment controller respectively.

In embodiments of the present invention, beam splitter receives downstream signal from radio equipment controller, is transferred to each wireless device again, thereby has realized that by beam splitter radio equipment controller is to each wireless device transmission of downlink signal.Because radio equipment controller is connected with beam splitter by optical fiber, beam splitter is connected separately with a plurality of wireless devices by optical fiber respectively again, can save a large amount of optical fiber than the point to point connect of prior art, annular connection, and project cost is low; Chain than prior art connects, because each wireless device all is connected with beam splitter by optical fiber respectively, can the phase mutual interference between each wireless device, when one of them wireless device breaks down or network upgrade need to increase wireless device the time, the proper communication that can not have influence between other wireless device and the radio equipment controller is professional; The signal transmission form that the embodiment of the invention adopts meets the existing network deployment scenario of present radio equipment controller and wireless device, has good compatibility.

Next introduce the another kind of method for transmitting signals that the embodiment of the invention provides, as shown in Figure 6, comprising:

601, each wireless device respectively by beam splitter with own between the optical fiber that is connected each up subsignal is sent to beam splitter.

Wherein, be connected by optical fiber between radio equipment controller and the beam splitter, beam splitter is connected separately with each wireless device by optical fiber respectively, each up subsignal carries a upper line identifier and a physical layer bursts expense, it is which wireless device sends that upper line identifier is used for up subsignal of expression, and the clock that the physical layer bursts expense is used for realizing each wireless device is synchronous with the clock of radio equipment controller;

The networking structure of the signal transmission system that the embodiment of the invention provides is that the optical fiber of PtMP connects, be that radio equipment controller is connected with beam splitter by optical fiber, beam splitter is connected with at least two wireless devices by different optical fiber respectively, for the beam splitter that the embodiment of the invention provides, a kind of implementation is that beam splitter can be the passive light power splitter, wherein, the passive light power splitter is a kind of passive optical fiber devices, cost is cheap, reliability is equal to optical fiber link, only introduce the certain power decay for the light signal of transmission, in the network of FTTx, extensive application is arranged.The networking structure of the signal transmission system that the embodiment of the invention is described specifically can referring to the description of previous embodiment and Fig. 3 and Fig. 4, repeat no more herein.

In embodiments of the present invention, a kind of feasible implementation is, each wireless device is with time division multiple access (TDMA, Time Division Multiple Access) mode sends upward signal to radio equipment controller, each wireless device at first sends to beam splitter by the optical fiber between own and the radio equipment controller with up subsignal, each up subsignal carries a upper line identifier and a physical layer bursts expense, the clock that the physical layer bursts expense is used for realizing described each wireless device is synchronous with the clock of described radio equipment controller, in the same way, each wireless device sends up subsignal in the TDMA mode to radio equipment controller, but the propagation delay time of inserting in each up subsignal is different, can guarantee strict time delay symmetry to guarantee each wireless device and radio equipment controller.

In actual applications, describe as an example of REC employing CPRI standard example, REC is connected with beam splitter by optical fiber, beam splitter has connected RE1 by different optical fiber respectively, RE2, ..., RE63 is totally 63 RE, the frame structure that each RE sends to the upward signal of beam splitter sees also shown in Figure 7, the frame structure schematic diagram of the upward signal that Fig. 7 provides for the embodiment of the invention, BFN is the frame of CPRI standard, frame length is 10ms, and the BFN of 10ms comprises altogether and is respectively RE1, ..., REn, ..., Hyperframe (Hyperframe) and PtMP control frame that RE63 distributes.Hyperframe be respectively #0 ..., #Z ..., #M, increase the expense (overhead) of several bytes on the structure of each Hyperframe, Identity Code (the ID that all comprises respectively each RE in the expense, IDentity) and the physical layer bursts expense, the payload of each Hyperframe (payload) also comprise 256 basic frames (basic frame) be respectively #0 ..., #x ..., #255.The ID and the physical layer bursts expense that also comprise each RE on the structure of PtMP control frame, the PtMP control frame refers to the physical layer control information that PtMP needs, the physical layer bursts expense is less than 8 bytes usually, and the REC that the physical layer bursts burst overhead time is used for receiver side realizes that signal is synchronous.According to existing CPRI standard, the Hyperframe quantity of supporting in the 10ms is 150, owing to having increased RE ID expense and PtMP control frame before each RE, is less than 149 therefore be total to M the Hyperframe of supporting in the embodiment of the invention.Certainly, along with the evolution of standard and the development of technology, the quantity of the Hyperframe of support can have other variations, describes as example at this, does not do restriction.

Need to prove, in embodiments of the present invention, the clock of each wireless device is synchronous with the clock maintenance of radio equipment controller respectively, and owing to each wireless device is connected with beam splitter by different optical fiber respectively, each wireless device is separate, and its clock separately is separate.

Need to prove, in the prior art, no matter point to point connect or chain connect or annular connects, the up subsignal that RE sends to REC is not carry line identifier, the embodiment of the invention represents to send to the upward signal of radio equipment controller with the sign of wireless device by the mode of time division multiple access, beam splitter can receive the up subsignal that each wireless device sends by the optical fiber that is connected between beam splitter and each wireless device.

602, radio equipment controller receives each up subsignal that beam splitter is transmitted by the optical fiber that is connected between beam splitter and the radio equipment controller.

In embodiments of the present invention, beam splitter is after each radio equipment controller receives up subsignal, beam splitter sends to radio equipment controller by the optical fiber that is connected between beam splitter and the radio equipment controller with each up subsignal, to realize that the up subsignal that each wireless device sends can be transferred to radio equipment controller, which up subsignal radio equipment controller identifies according to line identifier on each is which wireless device sends, and radio equipment controller can be distinguished the up subsignal that each wireless device sends according to up sign.

Need to prove, in embodiments of the present invention, the clock that the physical layer bursts expense be used for to realize each wireless device is realized synchronously in the following way with the clock of radio equipment controller: radio equipment controller is sampled to each up subsignal that beam splitter sends by local clock, finishes clock synchronous of the clock of each wireless device and radio equipment controller in the physical layer bursts expense.

In embodiment provided by the invention, radio equipment controller is connected with beam splitter by optical fiber, beam splitter is connected separately with each wireless device by optical fiber respectively, each wireless device respectively by beam splitter with own between the optical fiber that is connected each up subsignal is sent to beam splitter, radio equipment controller receives each up subsignal that beam splitter is transmitted by the optical fiber that is connected between beam splitter and the radio equipment controller, that is to say that beam splitter will send to radio equipment controller with each up subsignal by the optical fiber that is connected between beam splitter and the radio equipment controller, thereby realized that by beam splitter each wireless device transmits up subsignal to radio equipment controller.Because radio equipment controller is connected by optical fiber with beam splitter, beam splitter is connected by optical fiber with a plurality of wireless devices respectively again, can save a large amount of optical fiber than the point to point connect of prior art, annular connection, and project cost is low; Chain than prior art connects, because each wireless device all is connected with beam splitter by optical fiber respectively, can the phase mutual interference between each wireless device, when one of them wireless device breaks down or network upgrade need to increase wireless device the time, the proper communication that can not have influence between other wireless device and the radio equipment controller is professional; The signal transmission form that the embodiment of the invention adopts meets the existing network deployment scenario of present radio equipment controller and wireless device, has good compatibility.

Above embodiment has introduced the method for transmitting signals that the embodiment of the invention provides, next introduce the method for transmitting signals corresponding to previous embodiment, different from embodiment shown in Figure 6, the method for transmitting signals that is based on radio equipment controller and wireless device realization that Fig. 6 describes, next a kind of method for transmitting signals that is based on the beam splitter realization of describing comprises:

Beam splitter receives each up subsignal that each wireless device sends respectively, beam splitter is connected separately with each wireless device by optical fiber respectively, each up subsignal carries a upper line identifier and a physical layer bursts expense, it is which wireless device sends that upper line identifier is used for up subsignal of expression, and the clock that the physical layer bursts expense is used for realizing each wireless device is synchronous with the clock of radio equipment controller;

Beam splitter is transferred to radio equipment controller with each up subsignal, is connected by optical fiber between radio equipment controller and the beam splitter.

In embodiment provided by the invention, radio equipment controller is connected with beam splitter by optical fiber, beam splitter is connected separately with each wireless device by optical fiber respectively, beam splitter by with each wireless device between the optical fiber that is connected receive each up subsignal, and then each up subsignal sent to radio equipment controller, realized that by beam splitter each wireless device transmits up subsignal to radio equipment controller, because radio equipment controller is connected by optical fiber with beam splitter, beam splitter is connected by optical fiber with a plurality of wireless devices respectively again, point to point connect than prior art, the annular connection can be saved a large amount of optical fiber, and project cost is low; Chain than prior art connects, because each wireless device all is connected with beam splitter by optical fiber respectively, can the phase mutual interference between each wireless device, when one of them wireless device breaks down or network upgrade need to increase wireless device the time, the proper communication that can not have influence between other wireless device and the radio equipment controller is professional; The signal transmission form that the embodiment of the invention adopts meets the existing network deployment scenario of present radio equipment controller and wireless device, has good compatibility.

Above embodiment has introduced the method for transmitting signals that the embodiment of the invention provides, next introduce the signal transmission apparatus of using this method for transmitting signals, see also shown in Figure 8, the signal transmission apparatus 800 that the embodiment of the invention provides, comprise: radio equipment controller 801, a plurality of wireless device 802 (illustrated among Fig. 8 the first wireless device 8021, the second wireless device 8022 ..., N wireless device 802N, amount to N wireless device, N is natural number), wherein

Be connected by optical fiber between radio equipment controller 801 and the beam splitter 802, beam splitter is connected separately with each wireless device by optical fiber respectively;

Radio equipment controller 801 comprises: downlink broadcast unit 8011, uplink receiving unit 8012, each wireless device comprises respectively: descending receiving element, up transmitting element (for example, the first wireless device 8021 comprises the first descending receiving element 80211, the first up transmitting element 80212, the second wireless device 8022 comprises the second descending receiving element 80221, the second up transmitting element 80222, ..., N wireless device 802N comprises the descending receiving element 802N1 of N, the up transmitting element 802N2 of N, for convenient following the description, with the first descending receiving element 80211, the second descending receiving element 80221, ..., the descending receiving element 802N1 of N and be referred to as each descending receiving element, with the first up transmitting element 80212, the second up transmitting element 80222, ..., the up transmitting element 802N2 of N and be referred to as each up transmitting element), wherein

Downlink broadcast unit 8011, be used for the broadcast downstream signal to beam splitter, so that beam splitter is to a plurality of broadcast by wireless devices downstream signals, downstream signal includes a plurality of descending subsignals, each descending subsignal carries a lower line identifier, lower line identifier is used for descending subsignal of expression and belongs to which wireless device, and the clock of a plurality of wireless devices is synchronous with the clock maintenance of radio equipment controller respectively;

Each descending receiving element is respectively applied to the optical fiber by being connected between each wireless device and the beam splitter, receives one's own descending subsignal according to lower line identifier from downstream signal;

Each up transmitting element, be respectively applied to by the optical fiber that is connected between each wireless device and the beam splitter each up subsignal be sent to beam splitter, so that beam splitter is transferred to radio equipment controller with each up subsignal, each up subsignal carries a upper line identifier and a physical layer bursts expense, it is which wireless device sends that upper line identifier is used for up subsignal of expression, and the clock that the physical layer bursts expense is used for realizing each wireless device is synchronous with the clock of radio equipment controller;

Uplink receiving unit 8012 is used for receiving each up subsignal that beam splitter is transmitted by the optical fiber that is connected between beam splitter and the radio equipment controller.

Need to prove, the a plurality of wireless devices that provide in the embodiment of the invention refer at least two wireless devices, each wireless device 802 also comprises respectively (not shown in Figure 8): the time-delay calculation unit, wherein, each time-delay calculation unit is respectively applied to calculate respectively propagation delay time according to the one's own descending subsignal that receives, propagation delay time is used for revising up subsignal when each wireless device when radio equipment controller sends up subsignal, and is identical with the transmitted in both directions time delay between the radio equipment controller to guarantee each wireless device.

Need to prove, individual in embodiments of the present invention, a kind of feasible implementation is, radio equipment controller 801 can also comprise (not shown in Figure 8): range cells, wherein, range cells is used for opening ranging window when the wireless device that is subordinated to radio equipment controller is opened the station or broken down.

Need to prove, the contents such as the information interaction between the said apparatus, implementation, since with the inventive method embodiment based on same design, its technique effect that brings is identical with the inventive method embodiment, and particular content can be referring to the narration in the present invention such as Fig. 2 and the embodiment of the method shown in Figure 6.

In embodiment provided by the invention, radio equipment controller is connected with beam splitter by optical fiber, beam splitter is connected separately with each wireless device by optical fiber respectively, radio equipment controller broadcast downstream signal is to beam splitter, then beam splitter will be by the optical fiber that is connected between beam splitter and the radio equipment controller to this downstream signal of a plurality of broadcast by wireless devices, thereby has realized that by beam splitter radio equipment controller is to each wireless device transmission of downlink signal.Each wireless device respectively by beam splitter with own between the optical fiber that is connected each up subsignal is sent to beam splitter, radio equipment controller receives each up subsignal that beam splitter is transmitted by the optical fiber that is connected between beam splitter and the radio equipment controller, that is to say that beam splitter sends to radio equipment controller by the optical fiber that is connected between beam splitter and the radio equipment controller with each up subsignal, has realized that by beam splitter each wireless device transmits up subsignal to radio equipment controller.Because radio equipment controller is connected with beam splitter by optical fiber, beam splitter is connected separately with a plurality of wireless devices by optical fiber respectively again, can save a large amount of optical fiber than the point to point connect of prior art, annular connection, and project cost is low; Chain than prior art connects, because each wireless device all is connected with beam splitter by optical fiber respectively, can the phase mutual interference between each wireless device, when one of them wireless device breaks down or network upgrade need to increase wireless device the time, the proper communication that can not have influence between other wireless device and the radio equipment controller is professional; The signal transmission form that the embodiment of the invention adopts meets the existing network deployment scenario of present radio equipment controller and wireless device, has good compatibility.

Next introduce a kind of beam splitter that the embodiment of the invention provides, as shown in Figure 9, beam splitter 900 comprises:

The first receiving element 901, be used for receiving the downstream signal of radio equipment controller broadcasting, be connected by optical fiber between radio equipment controller and the beam splitter, downstream signal includes a plurality of descending subsignals, each descending subsignal carries a lower line identifier, and lower line identifier is used for descending subsignal of expression and belongs to which wireless device RE;

The first transmission unit 902, be used for to a plurality of broadcast by wireless devices downstream signals, so that a plurality of wireless devices receive respectively one's own descending subsignal according to lower line identifier from downstream signal, beam splitter is connected separately with each wireless device by optical fiber respectively, and the clock of a plurality of wireless devices is synchronous with the clock maintenance of radio equipment controller respectively;

The second receiving element 903, be used for receiving each up subsignal that each wireless device sends respectively, each up subsignal carries a upper line identifier and a physical layer bursts expense, it is which wireless device sends that upper line identifier is used for up subsignal of expression, and the clock that the physical layer bursts expense is used for realizing each wireless device is synchronous with the clock of radio equipment controller;

The second transmission unit 904 is used for each up subsignal is transferred to radio equipment controller.

In embodiments of the present invention, beam splitter receives downstream signal from radio equipment controller, be transferred to again each wireless device, beam splitter by with each wireless device between the optical fiber that is connected receive each up subsignal, and then each up subsignal is sent to radio equipment controller.Thereby realized that by beam splitter radio equipment controller is to each wireless device transmission of downlink signal.Because radio equipment controller is connected with beam splitter by optical fiber, beam splitter is connected separately with a plurality of wireless devices by optical fiber respectively again, can save a large amount of optical fiber than the point to point connect of prior art, annular connection, and project cost is low; Chain than prior art connects, because each wireless device all is connected with beam splitter by optical fiber respectively, can the phase mutual interference between each wireless device, when one of them wireless device breaks down or network upgrade need to increase wireless device the time, the proper communication that can not have influence between other wireless device and the radio equipment controller is professional; The signal transmission form that the embodiment of the invention adopts meets the existing network deployment scenario of present radio equipment controller and wireless device, has good compatibility.

Next, introduce a kind of signal transmission system that the embodiment of the invention provides, as shown in figure 10, signal system 1000 comprises: signal transmission apparatus 1001 as shown in Figure 8 and beam splitter as shown in Figure 9 1002,

Need to prove, the contents such as the information interaction between inner each equipment of said system, implementation, since with the inventive method embodiment based on same design, its technique effect that brings is identical with the inventive method embodiment, particular content can referring to the narration in the embodiment of the method for the present invention, repeat no more herein.

Need to prove, in actual applications, can comprise a plurality of wireless devices in the signal transmission system, a plurality of wireless devices are connected with beam splitter by optical fiber, and can also comprise a plurality of beam splitters in the signal transmission system in actual applications, for example as shown in Figure 4, comprise that take signal transmission system two beam splitters as example describes, are not limited to two beam splitters certainly, herein just explanation, do not do restriction, for example, in signal transmission system, except comprising beam splitter 1002, can also comprise another beam splitter (not shown in Figure 10), wherein

Radio equipment controller is connected with beam splitter 1002 by optical fiber, be connected by optical fiber between beam splitter 1002 and another beam splitter, beam splitter 1002 is connected separately with part wireless device in a plurality of wireless devices by optical fiber respectively, and another beam splitter is connected separately with remaining wireless device in a plurality of wireless devices by optical fiber respectively.Specific to as shown in Figure 4, beam splitter 1002 can be beam splitter 1, and another beam splitter can be beam splitter 2, and then beam splitter 1 is connected by optical fiber with RE1, RE2, RE3, and beam splitter 2 is connected by optical fiber with RE4, RE5.

The workflow of the signal transmission system that next embodiment of the invention is provided is elaborated: comprise that take signal transmission system radio equipment controller, beam splitter and two wireless devices (being specially the first wireless device and the second wireless device) describe as example, as shown in figure 11, what at first describe is the transmission course of downstream signal, explanation such as step 1101 and 1102, what then describe is the transmission course of up subsignal, such as the explanation of step 1103 to 1105.

1101, radio equipment controller broadcast downstream signal is to beam splitter.

1102, beam splitter is to the first wireless device and the second broadcast by wireless devices downstream signal.

1103, the first wireless device by beam splitter with own between the optical fiber that is connected the first up subsignal is sent to beam splitter.

1104, the second wireless device by beam splitter with own between the optical fiber that is connected the second up subsignal is sent to beam splitter.

1105, beam splitter is transferred to radio equipment controller with the first up subsignal and the second up subsignal.

In embodiment provided by the invention, radio equipment controller is connected with beam splitter by optical fiber, beam splitter is connected separately with each wireless device by optical fiber respectively, radio equipment controller broadcast downstream signal is to beam splitter, then beam splitter will by the optical fiber that is connected between beam splitter and the radio equipment controller to this downstream signal of a plurality of broadcast by wireless devices, realize that by beam splitter radio equipment controller is to each wireless device transmission of downlink signal.Each wireless device respectively by beam splitter with own between the optical fiber that is connected each up subsignal is sent to beam splitter, radio equipment controller receives each up subsignal that beam splitter is transmitted by the optical fiber that is connected between beam splitter and the radio equipment controller, that is to say that beam splitter sends to radio equipment controller by the optical fiber that is connected between beam splitter and the radio equipment controller with each up subsignal, has realized that by beam splitter each wireless device transmits up subsignal to radio equipment controller.Because radio equipment controller is connected with beam splitter by optical fiber, beam splitter is connected separately with a plurality of wireless devices by optical fiber respectively again, point to point connect than prior art, the annular connection can be saved a large amount of optical fiber, project cost is low, chain than prior art connects, because each wireless device all is connected with beam splitter by optical fiber respectively, can the phase mutual interference between each wireless device, when one of them wireless device breaks down or network upgrade need to increase wireless device the time, the proper communication that can not have influence between other wireless device and the radio equipment controller is professional; The signal transmission form that the embodiment of the invention adopts meets the existing network deployment scenario of present radio equipment controller and wireless device, has good compatibility.

One of ordinary skill in the art will appreciate that all or part of step that realizes in above-described embodiment method is to come the relevant hardware of instruction to finish by program, described program can be stored in a kind of computer-readable recording medium, the above-mentioned storage medium of mentioning can be read-only memory, disk or CD etc.

Above a kind of method for transmitting signals provided by the present invention and relevant device and signal transmission system are described in detail, for one of ordinary skill in the art, thought according to the embodiment of the invention, all will change in specific embodiments and applications, in sum, this description should not be construed as limitation of the present invention.

Claims

1. a method for transmitting signals is characterized in that, comprising:

2. method for transmitting signals according to claim 1, it is characterized in that, described each wireless device respectively by described beam splitter with oneself between the optical fiber that is connected, from described downstream signal, receive respectively after the one's own descending subsignal according to described lower line identifier, also comprise:

Described each wireless device calculates respectively propagation delay time according to the one's own descending subsignal that receives, described propagation delay time is used for revising described up subsignal when described each wireless device when described radio equipment controller sends up subsignal, and is identical with the transmitted in both directions time delay between the described radio equipment controller to guarantee described each wireless device.

3. method for transmitting signals according to claim 1 and 2 is characterized in that, described method for transmitting signals also comprises:

When the wireless device that is subordinated to described radio equipment controller was opened the station or broken down, described radio equipment controller was opened ranging window.

4. a method for transmitting signals is characterized in that, comprising:

5. a method for transmitting signals is characterized in that, comprising:

6. method for transmitting signals according to claim 5 is characterized in that, described method for transmitting signals also comprises:

7. according to claim 5 or 6 described method for transmitting signals, it is characterized in that, described physical layer bursts expense is used for realizing the synchronously in the following way realization of clock with the clock of described radio equipment controller of described each wireless device:

Described radio equipment controller is sampled to each up subsignal that described beam splitter sends by local clock, and the clock of finishing described each wireless device in described physical layer bursts expense is synchronous with the clock of described radio equipment controller.

8. a method for transmitting signals is characterized in that, comprising:

9. a signal transmission apparatus is characterized in that, comprising: radio equipment controller REC, a plurality of wireless device RE, wherein,

10. signal transmission system according to claim 9 is characterized in that, described each wireless device also comprises respectively: the time-delay calculation unit, wherein,

Each time-delay calculation unit, be respectively applied to calculate propagation delay time according to the one's own descending subsignal that receives, described propagation delay time is used for revising described up subsignal when described each wireless device when described radio equipment controller sends up subsignal, and is identical with the transmitted in both directions time delay between the described radio equipment controller to guarantee described each wireless device.

11. according to claim 9 or 10 described signal transmission systems, it is characterized in that, described radio equipment controller also comprises: range cells, wherein,

Described range cells is used for opening ranging window when the wireless device that is subordinated to described radio equipment controller is opened the station or broken down.

12. a beam splitter is characterized in that, comprising:

13. a signal transmission system is characterized in that, comprising: such as each described signal transmission apparatus, beam splitter as claimed in claim 12 in the claim 9 to 11.

14. signal transmission system according to claim 13 is characterized in that, described signal transmission system also comprises except comprising beam splitter as claimed in claim 12: another beam splitter, wherein,

Described radio equipment controller is connected with described beam splitter by optical fiber, be connected by optical fiber between described beam splitter and described another beam splitter, described beam splitter is connected separately with part wireless device in a plurality of wireless devices by optical fiber respectively, and described another beam splitter is connected separately with remaining wireless device in a plurality of wireless devices by optical fiber respectively.