Summary of the invention
For solving the bandwidth problem that prior art exists, the invention provides a kind of multi-wavelength passive optical network system.
Multi-wavelength passive optical network system provided by the invention comprises optical line terminal, Optical Distribution Network and a plurality of optical network unit, and described optical line terminal is connected to described optical network unit by described Optical Distribution Network in the mode of putting multiple spot; Wherein, described a plurality of optical network unit is divided into many groups, each group optical network unit adopts different up-downgoing wavelength respectively, described Optical Distribution Network comprises first order optical splitter and a plurality of second level optical splitter, wherein said first order optical splitter comprises up public port, descending public port, a plurality of up branch port and a plurality of descending branch port, wherein said up public port and descending public port are connected to described optical line terminal by up trunk optical fiber and descending trunk optical fiber respectively, and the descending branch port of described first order optical splitter is connected descending branch optical fiber and up branch optical fiber respectively with up branch port, and be connected to one group of optical network unit by one of them second level optical splitter, the descending branch port of described first order optical splitter is coated with transmission film respectively, and different transmission film has different transmission spectrums; Wherein, described optical line terminal comprises the BWmap territory to the frame head of the descending XGTC frame that described optical-fiber network sends, described BWmap territory comprises a plurality of distribution structures, and wherein each distribution structure comprises the wavelength indication field, and described wavelength indication field is used for carrying wavelength indication information.
In multi-wavelength passive optical network system one preferred embodiment provided by the invention, described a plurality of optical network unit is divided into four groups, and described first order optical splitter comprises four descending branch port, each descending branch port corresponds respectively to wherein one group of optical network unit, and described four branch port are coated with first transmission film, second transmission film, the 3rd transmission film and the 4th transmission film respectively.
In multi-wavelength passive optical network system one preferred embodiment provided by the invention, the central homology wavelength of described first transmission film is the downstream wavelength of first group of optical network unit, the central homology wavelength of described second transmission film is the downstream wavelength of second group of optical network unit, the central homology wavelength of described the 3rd transmission film is the downstream wavelength of the 3rd group of optical network unit, and the central homology wavelength of described the 4th transmission film is the downstream wavelength of the 4th group of optical network unit.
In multi-wavelength passive optical network system one preferred embodiment provided by the invention, described first order optical splitter also comprises four up branch port, described four branch port are connected with up branch optical fiber respectively, and are coupled to the descending branch optical fiber of its correspondence respectively by branch coupler.
In multi-wavelength passive optical network system one preferred embodiment provided by the invention, the channel wavelength of described four up branch port is respectively the up wavelength of the up wavelength of the up wavelength of described first group of optical network unit, described second group of optical network unit, described the 3rd group of optical network unit and the up wavelength of described the 4th group of optical network unit.
In multi-wavelength passive optical network system one preferred embodiment provided by the invention, described optical line terminal comprises a plurality of optical transmitting sets, and wherein the emission wavelength of each optical transmitting set is distinguished the wherein downstream wavelength of one group of optical network unit.
In multi-wavelength passive optical network system one preferred embodiment provided by the invention, described optical line terminal also comprises a plurality of optical receivers, and wherein the reception wavelength of each optical receiver is distinguished the wherein up wavelength of one group of optical network unit.
Multi-wavelength passive optical network system provided by the invention is divided into many groups with described optical network unit, and the descending branch port at described first order optical splitter adopts the plated film mode to realize the downstream wavelength separation, and realize up wavelength multiplexing by described first order optical splitter, thereby realize adopting respectively many up-downgoing data of the up-downgoing wavelength being carried not optical network unit on the same group respectively, thus, section just can utilize different wave length to transmit the data of a plurality of optical network units simultaneously at one time, thereby effectively the overall bandwidth of elevator system satisfies user's broadband services to the increased requirement of bandwidth.
Embodiment
To the technical scheme in the embodiment of the invention be clearly and completely described below, obviously, described embodiment only is a part of embodiment of the present invention, rather than whole embodiment.Based on the embodiment among the present invention, those of ordinary skills belong to the scope of protection of the invention not making all other embodiment that obtain under the creative work prerequisite.
See also Fig. 1, it is the schematic diagram of a kind of preferred embodiment of multi-wavelength passive optical network system provided by the invention.Described passive optical network 100 comprises at least one optical line terminal (OLT) 110, a plurality of optical network unit (ONU) 120-1~120-n and Optical Distribution Network (ODN) 130.Described optical line terminal 110 is connected to described a plurality of optical network unit 120-1~120-n by described Optical Distribution Network 130 with the form of putting multiple spot.Wherein, the direction from described optical line terminal 110 to described optical network unit 120-1~120-n is defined as down direction, and the direction from described optical network unit 120-1~120-n to described optical line terminal 110 is up direction.
Described passive optical network 100 can be the communication network of realizing the data distribution between described optical line terminal 110 and the described optical network unit 120-1~120-n without any need for active device, such as, in specific embodiment, the data distribution between described optical line terminal 110 and the described optical network unit 120-1~120-n can realize by the Passive Optical Components in the described Optical Distribution Network 130 (such as optical splitter or multiplexer).
Described optical line terminal 110 is usually located at the center, and (central office Central Office for example, CO), they can the described a plurality of optical network unit 120-1~120-n of unified management.Described optical line terminal 110 can serve as the media between described optical network unit 120-1~120-n and the upper layer network (not shown), to be forwarded to described optical network unit 120-1~120-n as downlink data from the data that described upper layer network receives, and will be forwarded to described upper layer network from the upstream data that described optical network unit 120-1~120-n receives.
Described optical network unit 120-1~120-n can be arranged on user's side position (such as user resident) by distributed earth.Described optical network unit 120-1~120-n can be the network equipment that is used for communicating with described optical line terminal 110 and user, particularly, described optical network unit 120-1~120-n can serve as the media between described optical line terminal 110 and the described user, for example, described optical network unit 120-1~120-n can be forwarded to described user with the downlink data that receives from described optical line terminal 110, and will be forwarded to described optical line terminal 110 as upstream data from the data that described user receives.Should be appreciated that the structure of described optical network unit 120-1~120-n and Optical Network Terminal (Optical Network Terminal, ONT) close, therefore in the scheme that present specification provides, can exchange between optical network unit and the Optical Network Terminal.
Described Optical Distribution Network 130 can be a data dissemination system, and it can comprise optical fiber, optical coupler, optical branching device, optical multiplexer and/or other equipment.In one embodiment, described optical fiber, optical coupler, optical branching device, optical multiplexer and/or other equipment can be Passive Optical Components, specifically, described optical fiber, optical coupler, optical branching device, optical multiplexer and/or other equipment can be that distribute data signals is the device that does not need power supply to support between described optical line terminal 110 and described optical network unit 120-1~120-n.In addition, in other embodiments, this Optical Distribution Network 130 can also comprise one or more treatment facilities, for example, and image intensifer or trunking (Relay device).In branched structure as shown in Figure 1, described Optical Distribution Network 130 specifically can extend to described a plurality of optical network unit 120-1~120-n from described optical line terminal 110, but also can be configured to other any points to the structure of multiple spot.
In multi-wavelength passive optical network system provided by the invention, described a plurality of optical network unit 120-1~120-n can be divided into many groups, and same group optical network unit adopts respectively with a pair of up-downgoing wavelength, and adopt time division multiplexing mode to carry out multiplexing; The up-downgoing wavelength difference that adopts of optical network unit on the same group not, and (Wavelength Division Multiplexing, WDM) mode is not carried out multiplexing with wavelength division multiplexing by different wave length between on the same group the optical network unit.
Such as, multi-wavelength passive optical network system 100 shown in Figure 1 can adopt four pairs of up-downgoing wavelength, for ease of describing, below described four pairs of up-downgoing wavelength are designated as the first up wavelength X u1 and the first downstream wavelength λ d1, the second up wavelength X u2 and the second downstream wavelength λ d2, the 3rd up wavelength X u3 and the 3rd downstream wavelength λ d3, the 4th up wavelength X u4 and the 4th downstream wavelength λ d4 respectively.And, described a plurality of optical network unit 120-1~120-n can be divided into four groups, wherein the up-downgoing wavelength of first group of optical network unit adopts the described first up wavelength X u1 and the first downstream wavelength λ d1 respectively, the up-downgoing wavelength of second group of optical network unit adopts the described second up wavelength X u2 and the second downstream wavelength λ d2 respectively, the up-downgoing wavelength of the 3rd group of optical network unit adopts the described the 3rd up wavelength X u3 and the 3rd downstream wavelength λ d3 respectively, and the up-downgoing wavelength of the 4th group of optical network unit adopts the described the 4th up wavelength X u4 and the 4th downstream wavelength λ d4 respectively.
Described optical line terminal 110 comprises a plurality of optical transmitting set Tx1~Tx4 and a plurality of optical receiver Rx1~Rx4, wherein said optical transmitting set Tx1~Tx4 is used for launching downlink data to described optical network unit 120-1~120-n, and the emission wavelength of described optical transmitting set Tx1~Tx4 is respectively the described first downstream wavelength λ d1, the described second downstream wavelength λ d2, described the 3rd downstream wavelength λ d3 and described the 4th downstream wavelength λ d4; Described optical receiver Rx1~Rx4 is used for receiving the upstream data from described optical network unit 120-1~120-n, and the reception wavelength of described optical receiver Rx1~Rx4 is respectively the described first up wavelength X u1, the described second up wavelength X u2, the described the 3rd up wavelength X u3 and the 4th up wavelength X u4.
Described optical transmitting set Tx1~Tx4 can be connected to descending output port (not indicating) by multiplexer 111, thereby described multiplexer 111 can carry out multiplexing formation multi-wavelength downstream signal with the downlink data of described optical transmitting set Tx1~Tx4 emission.Described optical receiver Rx1~Rx4 can be connected to up input port (indicate) by demodulation multiplexer 112, and described demodulation multiplexer 112 can will be demultiplexed into described optical receiver Rx1~Rx4 respectively from described a plurality of 120-1~120-n and the upstream data that carries through described Optical Distribution Network 130 transmission multi-wavelength upward signals.Described up input port and described descending output port can be connected respectively to up trunk optical fiber 135 and descending trunk optical fiber 136, described descending output port will be coupled to the descending trunk optical fiber 136 of described Optical Distribution Network 130 from the multi-wavelength downstream signal of described multiplexer 111, and described up input port will be coupled to described demodulation multiplexer 112 from the multi-wavelength upward signal of the up trunk optical fiber 135 of described Optical Distribution Network.
Described Optical Distribution Network 130 can adopt two trunk optical fibers, and has two-stage light splitting framework, and it comprises first order optical splitter 131, second level optical splitter 132-1~132-4, upgoing wave division multiplexer 133 and branch coupler 134-1~134-4.
Described first order optical splitter 131 can be the optical branching device of 2:8 for splitting ratio, and it comprises two public ports and eight branch port.One of them public port of described first order optical splitter 131 is as up public port, it is connected to described optical line terminal 110 by described up trunk optical fiber 135, and another public port is connected to described optical line terminal 110 as descending trunk optical fiber 136.And, wherein four branch port of described first order optical splitter 131 are as descending branch port, and be connected to described branch coupler 134-1~134-4 by descending branch optical fiber 137 respectively, and further be connected to the public port of described second level optical splitter 132-1~132-4 by described branch coupler 134-1~134-4 respectively.Four branch port of all the other of described first order optical splitter 131 are as uplink port, and are connected to described branch coupler 134-1~134-4 by up branch optical fiber 137 respectively.Described first order optical splitter 131 can carry out the light signal that receives from described descending branch optical fiber 136 to export to described descending branch optical fiber from described descending branch port respectively after the light-splitting processing, and the light signal of described up branch optical fiber is coupled to described up trunk optical fiber 135 and exports to described optical line terminal 110.
In the present embodiment, it is the optical branching device of 1:8,1:16,1:32 or 1:64 that described second level optical splitter 132-1~132-4 can adopt branching ratio, and namely it has a public port and a plurality of branch port.The branch port of each second level optical splitter 132-1~132-4 is connected to wherein one group of optical network unit by profile fiber 138 respectively, and wherein each profile fiber connects the described second level one of them branch port of optical splitter 132-1~132-4 and its corresponding optical network unit 120-1~120-n.
In the present embodiment, four descending branch port of described first order optical splitter 131 can be coated with first transmission film respectively, second transmission film, the 3rd transmission film and the 4th transmission film, wherein said first transmission film, described second transmission film, described the 3rd transmission film has different transmission spectrums respectively with described the 4th transmission film, particularly, the central homology wavelength of described first transmission film can be the described first downstream wavelength λ d1, the central homology wavelength of described second transmission film can be the described second downstream wavelength λ d2, the central homology wavelength of described the 3rd transmission film can be described the 3rd downstream wavelength λ d3, and the central homology wavelength of described the 4th transmission film can be described the 4th downstream wavelength λ d4.Based on above-mentioned transmission film, described first order optical splitter 131 can realize that just the downlink data of the different wave length that carries in will the multi-wavelength downstream signal from described optical line terminal 110 outputs to different branch optical fiber 137 respectively, and further exports to not on the same group optical network unit by described second level optical splitter 132-1~132-4.
Particularly, at down direction, the multi-wavelength downstream signal of described optical line terminal 110 outputs is through after described descending trunk optical fiber 136 transmission, be coupled to described first order optical splitter 131 by described trunk coupler 135,131 pairs of described multi-wavelength downstream signals of described first order optical splitter carry out the power light splitting and form after a plurality of multi-wavelength downstream signals, export to described a plurality of descending branch optical fiber by its descending branch port respectively.Because the descending branch port of described first order optical splitter 131 is coated with the transmission film of different transmission spectrums respectively, therefore, when described multi-wavelength downstream signal passes the descending branch port of described first order optical splitter 131, have only the light signal of one of them wavelength to pass through, the light signal of other wavelength is then by filtering.
Such as, the light signal of the descending branch port output of first of described first order optical splitter 131 is the downlink data with described first downstream wavelength λ d1, i.e. the downlink data of described optical transmitting set Tx1 emission; The light signal of second descending branch port output of described first order optical splitter 131 is the downlink data with described second downstream wavelength λ d2, i.e. the downlink data of described optical transmitting set Tx2 emission; The light signal of the 3rd descending branch port output of described first order optical splitter 131 is the downlink data with described the 3rd downstream wavelength λ d3, i.e. the downlink data of described optical transmitting set Tx3 emission; And the light signal of the 4th descending branch port output of described first order optical splitter 131 is the downlink data with described the 4th downstream wavelength λ d4, i.e. the downlink data of described optical transmitting set Tx4 emission.
Therefore, the light signal that is transferred to described second level optical splitter 132-1~132-4 by each descending branch optical fiber 137 is respectively the downlink data of the emission of described optical transmitting set Tx1~Tx4, described downlink data carries out after the power light splitting through described second level optical splitter 132-1~132-4, further is transferred to the optical network unit of corresponding group by described profile fiber 138.
And aspect up, the time slot transmission upstream data that the light network unit of each group adopts its up wavelength X u1~λ u4 respectively and authorizes at described optical line terminal 110, because each group optical network unit adopts different up wavelength respectively, therefore same time slot can have the optical network unit of the different up wavelength of a plurality of employings to send upstream data simultaneously.After the upstream data of the different wave length that described not on the same group optical network unit sends converges by its corresponding second level optical splitter 132-1~132-4 respectively, be coupled to the different up branch port of described first order optical splitter 131 by different branch coupler 134-1~134-4.Described first order optical splitter 131 further carries out being transferred to described optical line terminal 110 by described up trunk optical fiber 135 after the multiplexing formation multi-wavelength upward signal to the upstream data of described different wave length.
Multi-wavelength passive optical network system 100 provided by the invention is because described optical network unit 120-1~120-n is divided into many groups and each group adopts different operation wavelengths respectively, therefore, for certain optical network unit, which up-downgoing wavelength it does not also know oneself need be operated in.For realizing load balancing and avoid occurring the wavelength conflict that described optical line terminal 110 needs to specify to optical network unit assigned work wavelength, is about to the wavelength indication information and passes to described optical network unit.
In described multi-wavelength passive optical network system 100, though optical network unit does not adopt the mode of wavelength division multiplexing to carry out work on the same group, but can communicate according to the XGPON agreement between described optical line terminal 110 and each the group optical network unit, concrete protocol contents can be with reference to the ITU-TG.987 series standard.
In one embodiment, described optical line terminal 110 can be carried on described wavelength information descending XGTC (XG-PON Transmission Convergence, the XGPON Transmission Convergence) frame, and by described descending XGTC frame described wavelength indication information is offered described optical network unit.See also Fig. 2, the frame structure schematic diagram of a kind of embodiment of the descending XGTC frame that it can adopt for multi-wavelength passive optical network system 100 provided by the invention.Described descending XGTC frame can comprise XGTC frame head and XGTC payload.Described XGTC frame head can comprise HLend territory, bandwidth map (Bandwidth map, BWmap) territory and down physical layer operation management maintain (Physical Layer Operations, Administration and Maintenance downstream, PLOAMd) territory.Wherein, wherein, described BWmap territory can define the wavelength indication field.Particularly, described BWmap can comprise a plurality of distribution structures (Allocation Structure), wherein each distribution structure comprises wavelength indication (Wavelength Indicator) field respectively, allocation identification (Allocation Identification, Alloc-ID) field, sign (Flags) field, time started (Start Time) field, authorize length (Grant Size) field, pressure sign (the Forced Wake-up Indicator that revives, FWI) field, burst template (Burst Profile) field and hybrid error correction (Hybrid Error Correction, HEC) field.Described wavelength indication field is used for carrying described wavelength indication information, and in specific embodiment, described wavelength indication information can be numbered for wavelength.
Multi-wavelength passive optical network system 100 provided by the invention is divided into many groups with described optical network unit 120-1~120-n, and the descending branch port at described first order optical splitter 131 adopts the plated film mode to realize the downstream wavelength separation, and by the up wavelength multiplexing of described first order optical splitter 131 realizations, thereby realize adopting respectively many up-downgoing data of the up-downgoing wavelength being carried not optical network unit on the same group respectively, thus, section just can utilize different wave length to transmit the data of a plurality of optical network units simultaneously at one time, thereby effectively the overall bandwidth of elevator system satisfies user's broadband services to the increased requirement of bandwidth.
The above only is embodiments of the invention; be not so limit claim of the present invention; every equivalent structure or equivalent flow process conversion that utilizes description of the present invention to do; or directly or indirectly be used in other relevant technical field, all in like manner be included in the scope of patent protection of the present invention.