CN103139670A

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Info

Publication number: CN103139670A
Application number: CN2011103803145A
Authority: CN
Inventors: 付志明; 徐继东
Original assignee: ZTE Corp
Current assignee: ZTE Corp
Priority date: 2011-11-25
Filing date: 2011-11-25
Publication date: 2013-06-05
Anticipated expiration: 2031-11-25
Also published as: CN103139670B; WO2013075662A1

Abstract

The invention discloses a coexisting passive optical network (PON) system and an up and down optical signal transmitting method. The system comprises an xPON optical line terminal and a 10G-xPON optical line terminal which respectively transmit down optical signals to an optical network unit through a corresponding single-fiber interface and receive up optical signals transmitted by the optical network unit, a light guide device respectively connected with the xPON optical line terminal and the 10G-xPON optical line terminal and used for guiding the down optical signals and the up optical signals, a multimode coupler connected with the light guide device and used for distributing the down optical signals to an optical distribution network and coupling the up optical signals to the light guide device, the optical distribution network connected with the multimode coupler and used for transmitting the down optical signals to the optical network unit and transmitting the up optical signals to the multimode coupler and the optical network unit connected with the optical distribution network and used for receiving the input down optical signals and transmitting the up optical signals to the xPON optical line terminal or the 10G-xPON optical line terminal. By means of the system and the method, utilization of PON ports can be improved, and the effect of reducing operating cost can be achieved accordingly.

Description

Passive optical network and uplink and downlink optical signal transmitting method coexist

Technical field

The present invention relates to the communications field, in particular to a kind of passive optical network and uplink and downlink optical signal transmitting method of coexisting.

Background technology

Along with the fast development of Fibre Optical Communication Technology, and requirement low-cost, environmental protection, communication network is from core net, metropolitan area network to Access Network, and the network that all uses optical fiber to form has become basic Consensus.

In optical-fiber network, for some residential quarter that relatively disperses, each EPON only meets several users; For the residential quarter of population than comparatively dense, especially some height end subscribers residential quarter of mixing, each PON (Passive Optical Network, EPON) mouthful with number of users more limited, therefore need a large amount of PON eloquence can satisfy the network needs in office side.But, generally, the machine room limited space of office side, cause the quantity of PON mouth can not be too many, and, OLT (Optical Line Terminal, the quantity of the ONU that optical line terminal) can carry (Optical Network Unit, optical network unit) is almost unlimited.

Therefore, how to improve fully the PON mouth utilance, cut operating costs, it is something that present operator relatively pays close attention to, in existing certain methods, some methods utilize mode coupler that the PON mouth is merged, this method need to be transformed existing OLT, particularly the optical module in method need to adopt TOSA (Transmitter Optical Subassembly, the light emission secondary module) and ROSA (Receiver Optical Subassembly, light-receiving secondary module) the two-way optical module of two fibres.(please refer to Fig. 1, Fig. 1 is the schematic diagram of the passive optical network structure that coexists according to the GPON of correlation technique and XGPON for some EPONs that coexist.), if can do minimum change and can reuse original simplex optical module former OLT, will greatly improve the utilance of PON mouth, yet, a kind of effective solution do not provided in prior art.

(PON coexists for the EPON that coexists in correlation technique, be xPON and 10G-xPON, it can be expressed as two kinds of different combination collocations of EPON and 10G-EPON or GPON and XG-PON) in the lower problem of utilance of PON mouth, effective solution is not yet proposed at present.

Summary of the invention

The invention provides a kind of passive optical network and uplink and downlink optical signal transmitting method of coexisting, with the lower problem of utilance that solves at least above-mentioned PON mouth.

Preferably, image intensifer comprises: the first image intensifer, be connected to respectively the first wave-division multiplexer filter and the second wave-division multiplexer filter, and be used for the downlink optical signal from the xPON optical line terminal is amplified; The second image intensifer is connected to respectively the first wave-division multiplexer filter and the second wave-division multiplexer filter, is used for the downlink optical signal from the 10G-xPON optical line terminal is amplified.

Preferably, the first amplifier is the S-band image intensifer.

Preferably, the second amplifier is the L-band image intensifer.

Preferably, the S-band image intensifer is semiconductor amplifier SOA.

Preferably, the L-band image intensifer is SOA or fiber amplifier EDFA.

Preferably, the xPON optical line terminal to the wave-length coverage of the downlink optical signal of optical network unit transmission is: 1480nm to 1500nm; The 10G-xPON optical line terminal to the wave-length coverage of the downlink optical signal that optical network unit sends is: 1575nm to 1581nm.

According to a further aspect of the invention, provide a kind of downlink optical signal sending method of the EPON that coexists, having comprised: xPON optical line terminal or 10G-PON optical line terminal send downlink optical signal to lightguide; Lightguide receives downlink optical signal, with the downlink optical signal leaded light to the Multiple modes coupling device; Multi-mode coupler receives downlink optical signal, and downlink optical signal is distributed to a plurality of Optical Distribution Networks; Optical Distribution Network is distributed to a plurality of optical network units with downstream signal; Optical network unit receives the downlink optical signal of input.

By the present invention, employing adds the mode of wave-division multiplexer filter, multi-mode coupler and image intensifer in the EPON that existing GPON and XGPON coexist, solved prior art need to be to existing optical line terminal (OLT) for the utilance that the PON mouth is provided thus significantly transform the problem that has increased cost, and then reached and only need to carry out minimum change to existing optical line terminal (OLT) and can improve the utilance of PON, the effect that cuts operating costs.

Description of drawings

Accompanying drawing described herein is used to provide a further understanding of the present invention, consists of the application's a part, and illustrative examples of the present invention and explanation thereof are used for explaining the present invention, do not consist of improper restriction of the present invention.In the accompanying drawings:

Fig. 1 is the schematic diagram of the passive optical network structure that coexists according to the GPON of correlation technique and XGPON;

Fig. 2 is the structured flowchart of passive optical network of coexisting according to an embodiment of the invention;

Fig. 3 is the structured flowchart of the EPON that coexists of GPON and XGPON according to the preferred embodiment of the invention;

Fig. 4 is the structural representation of the first wave-division multiplexer filter according to the preferred embodiment of the invention;

Fig. 5 is the structural representation of the second wave-division multiplexer filter according to the preferred embodiment of the invention;

Fig. 6 is the structural representation of multi-mode coupler according to the preferred embodiment of the invention;

Fig. 7 is the downlink optical signal sending method flow chart according to the embodiment of the present invention;

Fig. 8 is the uplink optical signal sending method flow chart according to the embodiment of the present invention.

Embodiment

Hereinafter also describe in conjunction with the embodiments the present invention in detail with reference to accompanying drawing.Need to prove, in the situation that do not conflict, embodiment and the feature in embodiment in the application can make up mutually.

In actual applications, image intensifer can comprise: the first image intensifer, and be connected to respectively and be connected to respectively the first wave-division multiplexer filter and the second wave-division multiplexer filter, be used for the downlink optical signal from xPON optical line terminal 10 is amplified; The second image intensifer is connected to respectively and is connected to respectively the first wave-division multiplexer filter and the second wave-division multiplexer filter, is used for the downlink optical signal from 10G-xPON optical line terminal 20 is amplified.

Preferably, the first image intensifer can be the S-band image intensifer, and the second image intensifer can be the L-band image intensifer.In actual applications, the S-band image intensifer can be semiconductor amplifier (SOA); The L-band image intensifer can be SOA or fiber amplifier (EDFA); XPON optical line terminal 10 to the wave-length coverage of the downlink optical signal that optical network unit 50 sends is: 1480nm to 1500nm; 10G-xPON optical line terminal 20 to the wave-length coverage of the downlink optical signal that optical network unit 50 sends is: 1575nm to 1581nm.At this, Fig. 3 is not described in detail.

Fig. 3 is the structured flowchart of the EPON that coexists of GPON and XGPON according to the preferred embodiment of the invention, and the below is described in detail said system take preferred embodiment shown in Figure 3 as example:

In order to realize goal of the invention, five different functional modules have been newly increased in this optimum decision system, be respectively: the first wave-division multiplexer filter (WDM1) 42, the second wave-division multiplexer filter (WDM2) 44, multi-mode coupler (40), S-band image intensifer 46 and L-band image intensifer 48, the below is described in detail each functional module.

The first wave-division multiplexer filter (WDM1) 42: its major function is to the carrying out shunt of up-downgoing light and synthetic, can by separately independently multimode fiber be connected with the optical module of the OLT of the optical module of the OLT of GPON and XG-PON respectively, from the up photoconduction of the GPON of up optical channel on the OLT of GPON, and from the up photoconduction of the XG-PON of up optical channel on the OLT of XG-PON; And from the descending photoconduction of the OLT of GPON on the image intensifer of the S-band of the descending optical channel of GPON, and from the descending photoconduction of the OLT of XG-PON on the image intensifer of the L-band of the descending optical channel of XG-PON, be a kind of multichannel passive leaded light device, can carry out leaded light to it by the mode of wavelength-division.

In actual applications, can adopt existing film filtering TFF technology, complete this function with three linear filter sheets, please participate in Fig. 4, Fig. 4 is the structural representation of the first wave-division multiplexer filter according to the preferred embodiment of the invention, as shown in Figure 4, it has two types, a kind of is sideband filter take 1450nm as separation, for wavelength less than the transmission mouth turnover from it of the light of 1450nm, and to wavelength greater than the light of 1450nm from its reflex port turnover; Another kind is the sideband filter take 1280nm as separation, for wavelength less than the transmission mouth turnover from it of the light of 1280nm, and to wavelength greater than the light of 1280nm from its reflex port turnover.Wherein, the general-purpose interface C of first side band filter is connected with up optical channel by multimode fiber, and its transmission mouth P is connected with the transmission interface P of the 3rd sideband filter, with and reflex port R be connected with the transmission interface P of Second Edge band filter; The general-purpose interface C of Second Edge band filter is connected with the OLT optical module of GPON by multimode fiber, and its reflex port R is connected with the S-band image intensifer of descending optical channel by monomode fiber; The general-purpose interface C of the 3rd sideband filter is connected with the OLT optical module of XG-PON by multimode fiber, and its reflex port R is connected with the L-band image intensifer of descending optical channel by monomode fiber; So just can complete the leaded light of five different passages.

The second wave-division multiplexer filter (WDM2) 44: its major function is to the carrying out shunt of up-downgoing light and synthetic, can be connected with multi-mode coupler by multimode fiber, descending light from different monomode fibers is converged on rear guiding multi-mode coupler, and the up light of multi-mode coupler is led on the WDM1 filter by multimode fiber.

In actual applications, can adopt existing film filtering TFF technology, complete this function with two linear filter sheets, see also Fig. 5, Fig. 5 is the structural representation of the second wave-division multiplexer filter according to the preferred embodiment of the invention, as shown in Figure 5, it has two types, a kind of is sideband filter take 1450nm as separation, for wavelength less than the transmission mouth turnover from it of the light of 1450nm, and to wavelength greater than the light of 1450nm from its reflex port turnover; Another kind is the sideband filter take 1550nm as separation, for wavelength less than the transmission mouth turnover from it of the light of 1550nm, and to wavelength greater than the light of 1550nm from its reflex port turnover.Wherein, the general-purpose interface C of first side band filter is connected with multi-mode coupler by multimode fiber, and its transmission mouth P is connected with the WDM1 filter by multimode fiber, with and reflex port R be connected with the general-purpose interface C of Second Edge band filter; The transmission interface P of Second Edge band filter is connected with the image intensifer of the S-band of descending optical channel, and the image intensifer of the L-band of the descending optical channel of its reflex port R is connected; So just can complete the leaded light of four different passages.

Multi-mode coupler 40: its major function is that up being optically coupled in from a plurality of ODN is input on the WDM2 filter together, and the descending light from the WDM2 filter is evenly distributed on the trunk optical fiber of a plurality of ODN.See also Fig. 6, Fig. 6 is the structural representation of multi-mode coupler according to the preferred embodiment of the invention, as shown in Figure 6, up light is transferred on the WDM2 filter by multimode fiber after monomode fiber is aggregated, and descending light is evenly distributed on a plurality of monomode fibers by multimode fiber; This flowcollector aggregation scheme FlowCollector can be lens, also can merge mode the coupling light on multimode fiber a plurality of monomode fibers such as vertebral pulling and fiber waveguide.

S-band image intensifer 46: its major function is that the descending light to the OLT of GPON amplifies, due to the descending light of GPON at 1480nm between 1500nm, therefore, its service band is positioned at S-band, usually selects the SOA of S-band as its image intensifer.

L-band image intensifer 48: its major function is that the descending light to the OLT of XG-PON amplifies, due to the descending light of XG-PON at 1575nm between 1581nm, therefore, its service band is positioned at L-band, usually selects the EDFA of L-band or SOA as its image intensifer.

wherein, for the annexation between modules, also please refer to Fig. 3, the consolidation problem of four ODN once here mainly is described, at first, the trunk optical fiber of four ODN is connected with multi-mode coupler, then be connected with the WDM2 filter by multimode fiber, its transmission interface is connected with the general-purpose interface C of WDM1 filter by multimode fiber, and the WDM1 filter directly is connected with the simplex optical module of GPON-OLT and is connected with the simplex optical module of XG-PON-OLT respectively by different multimode fibers, after the monomode fiber of the single mode passage of last WDM1 filter by separately connects respectively different separately image intensifers, the monomode fiber that passes through separately again is connected with the WDM2 filter respectively.Certainly, in actual applications, being not limited to only have the merging of four ODN, can be N ODN, and the multi-mode coupler that only needs to change corresponding 1:N gets final product.

operation principle and the workflow of said system are as follows: at first, be provided with the OLT of a GPON and the OLT of an XG-PON in office side, multimode fiber by its optical module separately is connected with wave-division multiplexer filter WDM1 respectively, the multimode fiber of their descending light by separately arrives and enters respectively the descending optical channel separately that is comprised of monomode fiber separately after WDM1, wherein the descending light of GPON enters the image intensifer of the S-band on the descending optical channel of GPON, arrive on wave-division multiplexer filter WDM2 after amplifying, and the descending light of XG-PON enters the image intensifer of the L-band on the descending optical channel of XG-PON, also arrive on wave-division multiplexer filter WDM2 after amplifying, then after closing ripple, WDM2 enters multi-mode coupler by multimode fiber, enter the trunk optical fiber of connected ODN after the even light splitting of this coupler, pass through trunk optical fiber, optical splitter and branch optical fiber arrive on each ONU, wherein the ONU of GPON only accepts the signal of GPON, and the ONU of XG-PON only accepts the signal of XG-PON.And the up light that these ONU upload, pass on coupled multi-mode coupler through corresponding ODN, then enter by multimode fiber and close on Waveguide module WDM2, be directed to up optical channel, this is that multimode fiber connects WDM2 and WDM1, on the multimode fiber that WDM1 leads respectively with the optical module of separately OLT is connected, then enters on OLT separately, be the OLT that the up light of GPON imports to GPON, and the up light of XG-PON import on the OLT of XG-PON.

particularly, at first, the descending light of the OLT of GPON arrives on the WDM1 filter by multimode fiber, the descending light of the OLT of XG-PON also arrives on the WDM1 filter by another root multimode fiber simultaneously, after leaded light, the descending light of GPON enters on the image intensifer of the S-band on the first descending optical channel, and the descending light of XG-PON also enters on the image intensifer of the L-band on the second descending optical channel simultaneously, after amplifying the descending light of the descending light of GPON and XG-PON respectively the monomode fiber by separately directly enter the WDM2 filter, arrive on multi-mode coupler by multimode fiber after converging, then divide on its four monomode fibers uniformly, trunk optical fiber by connected ODN enters corresponding ODN network, through optical splitter, branch optical fiber arrives on each ONU.

The up light of each ONU arrives on corresponding ODN optical splitter by branch optical fiber separately, trunk optical fiber through being attached thereto arrives the single-mode interface of multi-mode coupler, then going out the multimode interface arrives on the WDM2 filter through multimode fiber, arrive on the WDM1 filter by multimode fiber through leaded light, then the multimode interface separately that leads namely leads the up light of the ONU of GPON on the optical module of GPON-OLT by multimode fiber; And on the optical module of the up light of the ONU of XG-PON by another root multimode fiber guiding XG-PON-OLT.

Need to prove, also can carry out with reference to top embodiment for EPON and 10G-EPON, namely EPON replaces GPON, and the XG-PON of 10G-EPON replacement simultaneously gets final product.

The passive optical network that coexists that adopts above-described embodiment to provide, can be only to existing optical line terminal (OLT) thus significantly transform the problem that has increased cost, and then reached and only need to carry out minimum change to existing optical line terminal (OLT) and can improve the utilance of PON, the effect that cuts operating costs.

Fig. 7 is the downlink optical signal sending method flow chart according to the embodiment of the present invention, and as shown in Figure 7, the method mainly comprises the following steps (step S702-step S710):

Step S702, xPON optical line terminal or 10G-xPON optical line terminal send downlink optical signal to lightguide;

Step S704, lightguide receive downlink optical signal, with the downlink optical signal leaded light to the Multiple modes coupling device;

Step S706, multi-mode coupler receives downlink optical signal, and downlink optical signal is distributed to a plurality of Optical Distribution Networks (ODN);

Step S708, Optical Distribution Network is distributed to a plurality of optical network units with downlink optical signal;

Step S710, optical network unit receives the downlink optical signal of input.

Fig. 8 is the uplink optical signal sending method flow chart according to the embodiment of the present invention, and as shown in Figure 8, the method mainly comprises the following steps (step S802-step S810):

Step S802, optical network unit sends uplink optical signal to Optical Distribution Network;

Step S804, Optical Distribution Network is transferred to multi-mode coupler with uplink optical signal;

Step S806, multi-mode coupler receives uplink optical signal, sends to lightguide after uplink optical signal is coupled;

Step S808, lightguide carries out leaded light to the uplink optical signal that receives, and the uplink optical signal after leaded light is input to xPON optical line terminal or 10G-xPON optical line terminal;

Step S810, xPON optical line terminal or 10G-xPON optical line terminal receive the uplink optical signal of input.

The uplink and downlink optical signal transmitting method that adopts above-described embodiment to provide, can solve in prior art the problem that increases a plurality of optical line terminals (OLT) and increase cost, and then only reach need and carry out minimum change to existing optical line terminal (OLT) and can improve the utilance of PON, the effect that cuts operating costs.

From above description, can find out, the present invention has realized following technique effect: by add the mode of wave-division multiplexer filter, multi-mode coupler and image intensifer in the EPON that existing xPON and 10G-xPON coexist, solved prior art need to be to existing optical line terminal (OLT) for the utilance that the PON mouth is provided thus significantly transform the problem that has increased cost, and then reached and only need to carry out minimum change to existing optical line terminal (OLT) and can improve the utilance of PON, the effect that cuts operating costs.

The above is only the preferred embodiments of the present invention, is not limited to the present invention, and for a person skilled in the art, the present invention can have various modifications and variations.Within the spirit and principles in the present invention all, any modification of doing, be equal to replacement, improvement etc., within all should being included in protection scope of the present invention.

Claims

1. the passive optical network that coexists, is characterized in that, comprising:

The xPON optical line terminal is used for sending downlink optical signal by its single optical fiber interface to optical network unit, and receives the uplink optical signal that described optical network unit sends;

The 10G-xPON optical line terminal is used for sending described downlink optical signal by its single optical fiber interface to described optical network unit, and receives the uplink optical signal that described optical network unit sends;

Lightguide, be connected to respectively described xPON optical line terminal and described 10G-xPON optical line terminal, be used for respectively to the described downlink optical signal from described xPON optical line terminal and described 10G-xPON optical line terminal, and carry out leaded light from the described uplink optical signal of described optical network unit;

Multi-mode coupler is connected to described lightguide, is used for described downlink optical signal is distributed to a plurality of Optical Distribution Networks, and will be coupled to described lightguide by the described uplink optical signal that Optical Distribution Network sends;

Described Optical Distribution Network is connected to described multi-mode coupler, is used for described downlink optical signal is transferred to a plurality of optical network units, and described uplink optical signal is transferred to multi-mode coupler;

Described optical network unit is connected to described Optical Distribution Network, is used for receiving the described downlink optical signal of input, and sends described uplink optical signal to described xPON optical line terminal or described 10G-xPON optical line terminal.

2. system according to claim 1, is characterized in that,

Described lightguide comprises:

the first wave-division multiplexer filter, be connected to respectively described xPON optical line terminal and described 10G-xPON optical line terminal, be used for the described downlink optical signal from described xPON optical line terminal and described 10G-xPON optical line terminal is carried out shunt by the mode of wavelength-division, will be through the image intensifer extremely separately of the described downlink optical signal leaded light after shunt, with the described uplink optical signal from described optical network unit is carried out shunt by the mode of wavelength-division, will be through the described uplink optical signal difference leaded light after shunt to described xPON optical line terminal and described 10G-xPON optical line terminal,

The second wave-division multiplexer filter, its first interface is connected to described the first wave-division multiplexer filter by described image intensifer, be used for the described downlink optical signal after amplifying through described image intensifer is synthesized, will be through the described downlink optical signal leaded light after synthetic to described multi-mode coupler, with, its second interface directly is connected with described the first wave-division multiplexer filter, is used for the direct leaded light of described uplink optical signal to described the first wave-division multiplexer filter;

Described system also comprises: described image intensifer, be connected to respectively described the first wave-division multiplexer filter and described the second wave-division multiplexer filter, be used for the described downlink optical signal from described xPON optical line terminal and described 10G-xPON optical line terminal is respectively amplified.

3. system according to claim 2, is characterized in that, described image intensifer comprises:

The first image intensifer is connected to respectively described the first wave-division multiplexer filter and described the second wave-division multiplexer filter, is used for the described downlink optical signal from described xPON optical line terminal is amplified;

The second image intensifer is connected to respectively described the first wave-division multiplexer filter and described the second wave-division multiplexer filter, is used for the described downlink optical signal from described 10G-xPON optical line terminal is amplified.

4. system according to claim 3, is characterized in that, described the first amplifier is the S-band image intensifer.

5. system according to claim 4, is characterized in that, described the second amplifier is the L-band image intensifer.

6. system according to claim 5, is characterized in that, described S-band image intensifer is semiconductor amplifier SOA.

7. system according to claim 5, is characterized in that, described L-band image intensifer is described SOA or fiber amplifier EDFA.

8. any one described system according to claim 1 to 7, is characterized in that,

Described xPON optical line terminal to the wave-length coverage of the described downlink optical signal that described optical network unit sends is: 1480nm to 1500nm;

Described 10G-xPON optical line terminal to the wave-length coverage of the described downlink optical signal that described optical network unit sends is: 1575nm to 1581nm.

9. the downlink optical signal sending method of the EPON that coexists, is characterized in that, comprising:

XPON optical line terminal or 10G-PON optical line terminal send downlink optical signal to lightguide;

Described lightguide receives described downlink optical signal, with described downlink optical signal leaded light to the Multiple modes coupling device;

Described multi-mode coupler receives described downlink optical signal, and described downlink optical signal is distributed to a plurality of Optical Distribution Networks;

Described Optical Distribution Network is distributed to a plurality of optical network units with described downstream signal;

Described optical network unit receives the described downlink optical signal of input.

10. the uplink optical signal sending method of the EPON that coexists, is characterized in that, comprising:

Optical network unit sends uplink optical signal to Optical Distribution Network;

Described Optical Distribution Network is transferred to multi-mode coupler with described uplink optical signal;

Described multi-mode coupler receives described uplink optical signal, sends to lightguide after described uplink optical signal is coupled;

Described lightguide carries out leaded light to the described uplink optical signal that receives, and the described uplink optical signal after leaded light is input to xPON optical line terminal or 10G-PON optical line terminal;

Described xPON optical line terminal or described 10G-PON optical line terminal receive the described uplink optical signal of input.