CN102355611A

CN102355611A - Method for obtaining wavelength values by optical network units (ONUs) in WDM (Wavelength Division Multiplexing)-GPON (Gigabit Passive Optical Network) system

Info

Publication number: CN102355611A
Application number: CN2011103554814A
Authority: CN
Inventors: 曹桦
Original assignee: Fiberhome Telecommunication Technologies Co Ltd
Current assignee: Fiberhome Telecommunication Technologies Co Ltd
Priority date: 2011-11-11
Filing date: 2011-11-11
Publication date: 2012-02-15

Abstract

The invention provides a method for obtaining wavelength values by optical network units (ONUs) in a WDM (Wavelength Division Multiplexing)-GPON (Gigabit Passive Optical Network) system, and relates to the field of optical fiber communication. The method comprises the following steps: A01. when an optical line terminal (OLT) has no effective physical layer operation administration and maintenance (OAM) message, sending a 'No message' to a group of the ONUs butted with the OLT, filling the wavelength values of optical signals to be sent which need to be set by the group of the ONUs to a reserved field of the 'No message', and sending the 'No message' to the group of the ONUs; and A02. after each ONU in the group of the ONUs receives the 'No message' containing the wavelength values sent by the OLT, adjusting the optical signals sent by each ONU according to the wavelength values, and finally sending the adjusted optical signals to the OLT butted with the group of the ONUs. By adopting the method, the ONUs can quickly and conveniently obtain the wavelength values of the uplink optical signals, and finally the OLT can successfully receive the optical signals sent by the ONUs.

Description

Optical network unit obtains the method for wavelength value in the WDM-GPON system

Technical field

The present invention relates to fiber optic communication field, specifically be a kind of in the WDM-GPON system optical network unit obtain the method for wavelength value.

Background technology

WDM-GPON hybrid passive optical network technology is to combine ripe DWDM (Dense Wavelength Division Multiplexing; Intensive multiplexed optical wave is used) technology and GPON (Gigabit Passive Optical Network; Gigabit passive optical network) advantage of technology is added the laser technique of sending wavelength-tunable and an emerging technology that occurs.The biggest advantage of WDM-GPON hybrid passive optical network system is; Carry of multichannel GPON system on one road GPON system upgrade to a trunk optical fiber carry on the traditional trunk optical fiber; Each GPON system takies a wavelength channel; A plurality of GPON system then takies a plurality of wavelength channels, a plurality of wavelength channels close ripple and partial wave is then accomplished by no hot AAWG (Athermal Arrayed Waveguide Grating, array waveguide grating).

Be illustrated in figure 1 as the pie graph of WDM-GPON hybrid passive optical network system; A typical WDM-GPON hybrid passive optical network system structure comprises optical line terminal (OLT:Optical Line Termination), Optical Distribution Network (ODN:Optical Distribution Network) and optical network unit parts such as (ONU:Optical Network Unit); Wherein ODN comprises Heatless AWG and optical branching device (Optical Splitter) and circuit optical fiber, and λ is the respective wavelength value.

In the WDM-GPON hybrid passive optical network; Owing to adopted closing ripple and dividing wave technology based on DWDM; Therefore exist in the ODN network and be used for the no hot AAWG that a plurality of wavelength close ripple and partial wave; So employed wavelength channel has 16 ripples, 32 ripples even more respectively in the uplink and downlink passage in the system,, can increase the manufacturing cost of manufacturer and the maintenance cost of operator undoubtedly if each wavelength channel just adopts a kind of optical module of corresponding wavelength with it.Usually require in the system optical module among the OLT and ONU on model and kind, can accomplish unified; Be that the OLT side is all only with one type optical module; The ONU side also all only use a kind of optical module, rather than every kind of wavelength channel optical module of one type of correspondence just, so it is variable to require laser in the optical module to be wavelength-tunable; It is colourless that just usually said optical module requires, and like this OLT or ONU side all only need to adopt a kind of optical module of wavelength-tunable to get final product.

On the down direction in the WDM-GPON hybrid passive optical network (OLT transmission → ONU reception); Because OLT can confirm that it sends the wavelength value of light signal according to the residing physical location of its port; The port that also connects simultaneously corresponding AAWG according to this wavelength value is so the light signal that OLT sends can waltz through the whole AAWG among the ODN and arrive corresponding with it ONU very much.But on up direction (ONU transmission → OLT reception) problem has appearred but; Because the wavelength value that requires all ONU to send light signal in the WDM-GPON system can both be accomplished adjustable; And can with its AAWG wavelength channel of corresponding connection be complementary; When the wavelength value that allows to pass through when the wavelength value of the uplink optical signal that far-end ONU sends and port on the AAWG that this ONU is connected is not inconsistent; The light signal of this wavelength can not pass through said AAWG, if still adopt here the ITU-T that continues to use in the WDM-GPON system G.984.3 in the standard OLT send to the words of PLOAM (Physical Layer OAM, physical layer operations management maintenance) the message packet form of ONU; Owing to do not comprise the wavelength information of the correct suitable up transmission light signal of ONU in the message packet; Will make ONU can't regulate the transmission light signal of ONU apace according to correct wavelength value, cause the up transmission light signal of ONU can not pass through AAWG, make OLT can't receive the response message information of ONU; Thereby can't find ONU, finally make whole system can't get into normal operating conditions apace.

Summary of the invention

To the defective that exists in the prior art; The object of the present invention is to provide a kind of in the WDM-GPON system optical network unit obtain the method for wavelength value; The up light that ONU is required sends the signal wave long value and is filled in the reserved field of descending " No message "; Make ONU can therefrom obtain the wavelength value that its up light sends signal quickly and easily, finally let OLT successfully receive the light signal that this ONU sends.

For reaching above purpose; The technical scheme that the present invention takes is: a kind of in the WDM-GPON system optical network unit obtain the method for wavelength value; Comprise the steps: that A01. works as optical line terminal when not having effective physical layer operations management maintenance message, send " No message ", the wavelength value of the transmission light signal that said one group of optical network unit need be provided with to a set of network elements of docking with it; Be filled in the reserved field of " No message ", and send to this group optical network unit; A02. after each optical network unit in said one group of optical network unit is received " the No message " that contains wavelength value of optical line terminal transmission; Light signal according to said each optical network unit of wavelength value adjustment sends is sent to the optical line terminal that docks with this group optical network unit.

On the basis of technique scheme, said " No message " constantly sends to optical network unit and does not have the number of times restriction.

On the basis of technique scheme, said " No message " length overall is 12 bytes, and the 3rd byte to the 12 bytes are reserved field.

On the basis of technique scheme, in the said steps A 01, the wavelength value of said transmission light signal is carried out binary code, and said binary code is inserted the 3rd byte of " No message ".

On the basis of technique scheme, said wavelength value is different, and its binary code is also different.

On the basis of technique scheme, after said optical network unit is received " the No message " that contains wavelength value,, and according to the wavelength value that the wavelength value table of comparisons is converted into correspondence from the 3rd byte-extraction binary code.

On the basis of technique scheme, in the said steps A 02, optical network unit is provided with optical sender, and optical sender is regulated the light signal that will send according to said wavelength value, makes the two wavelength value consistent.

On the basis of technique scheme, in the said WDM-GPON system non-heat array wave guide grating is set, the wavelength value that requires on its wavelength channel port is identical with the wavelength value of said transmission light signal.

On the basis of technique scheme, said physical layer operations management maintenance message is observed the G.984.3 message format of standard of ITU-T.

Beneficial effect of the present invention is: the wavelength value of the transmission light signal that ONU need be provided with; Insert in the reserved field of " No message " in OLT one side; After ONU receives " No message "; Extract the wavelength value of sending light signal quickly and easily, and by the light signal that its adjusting will be sent, guarantee that the wavelength value that uplink optical signal that ONU sends and AAWG port allow to pass through is consistent; Finally let OLT successfully receive the light signal that this ONU sends, make whole system can't get into normal operating conditions apace.

Description of drawings

Fig. 1 is a WDM-GPON hybrid passive optical network system sketch map in the background technology.

Embodiment

Below the present invention is done further explain.

According to the invention in the WDM-GPON system optical network unit obtain the method for wavelength value, comprise the steps:

A01. when OLT does not have effective physical layer operations management maintenance message; To send " No message " to the one group of ONU that docks with it; The wavelength value of the transmission light signal that said one group of ONU need be provided with is filled in the reserved field of " No message ", and sends to this group ONU.

A02. after each ONU among said one group of ONU received " the No message " that contains wavelength value of optical line terminal transmission, the light signal according to said each ONU of wavelength value adjustment sends was sent to the OLT that docks with this group ONU.

Foundation of the present invention does; G.984.3, ITU-T through analyzing the WDM-GPON system can find after the descending PLOAM message in the standard; When OLT does not have effective PLOAM message to send; Will send " No message " to the one group of ONU that docks with it, this message will constantly send to each ONU in this group and not have the number of times restriction, so just can guarantee that all ONU in this group at any time can receive " No message ".

Table 1

Byte number	Content	Describe
			1	11111111	Broadcast to all ONU transmissions
2	00001011	Show that type of message is " no message "
			3～12	Do not stipulate	Reserve

In the said WDM-GPON system, the form of descending " No message " message that OLT sends is as shown in table 1, and its length overall is in the form of 12 bytes; The 1st byte is the broadcast of sending to the one group of ONU that docks with it; The 2nd byte is for showing that type of message is " no message ", and the content of the 3rd byte to the 12 bytes is not stipulated, belongs to reserved field; Therefore the present invention has utilized this part reserved field just, reaches the purpose that ONU obtains the wavelength value of light signal.

Through specific embodiment the present invention is further specified below.

The concrete steps of present embodiment are following:

Table 2

The wavelength value numbering	Wavelength value	Binary code
			1	λ1	00000001
2	λ2	00000010
			3	λ3	00000011
4	λ4	00000100
			5	λ5	00000101
6	λ6	00000110
			7	λ7	00000111
8	λ8	00001000
			9	λ9	00001001
10	λ10	00001010
			11	λ11	00001011
12	λ12	00001100
			13	λ13	00001101
14	λ14	00001110
			15	λ15	00001111
16	λ16	00010000

S101. when OLT does not have effective physical layer operations management maintenance message; Need be when the one group of ONU that docks with it sends " No message " (being " message of no content " that G.984.3 ITU-T defines in the standard); The wavelength value of the transmission light signal that need be provided with this group ONU is carried out binary code; And note making the corresponding binary code of each wavelength value, the binary code of different wave length value correspondence is also different.The corresponding relation of each wavelength value and binary code is as shown in table 2 in the present embodiment, and OLT is converted into corresponding binary code with each wavelength value, and each binary code is 8.In addition, in a WDM-GPON system, comprise a plurality of OLT, the above-mentioned one group of ONU that refers to each OLT and dock with it

Table 3

As shown in table 3; Descending " No message " message for the OLT transmission; That is,, insert any byte in the 3rd byte to the 12 bytes of " No message " with 8 binary codes after each conversion; Be the 3rd byte in the present embodiment, OLT constantly sends " No message " to the one group of ONU that docks with it then.

S102. in the WDM-GPON system; After also not obtaining each ONU among one group of ONU of wavelength value that up light sends signal and receiving " the No message " that has wavelength value; From the 3rd byte of " No message ", extract binary code; And according to the contrast of the wavelength value in the table 2, the corresponding wavelength value of each binary code converts.The optical sender that is provided with among each ONU is then regulated the uplink optical signal that will send according to said wavelength value, makes the two wavelength value consistent.Owing in the WDM-GPON system two no hot AAWG are set, there is not the wavelength value of hot AAWG wavelength channel port requirement, have only identical with the wavelength value of said transmission light signal; The uplink optical signal that ONU sends could pass through; Therefore under this kind mode, the wavelength value of the uplink optical signal after ONU regulates, the wavelength value that allows to pass through with the AAWG port is consistent; Finally let OLT successfully receive the light signal that each ONU sends in this group, make whole system get into normal operating conditions apace.

The present invention is not limited to above-mentioned execution mode, for those skilled in the art, under the prerequisite that does not break away from the principle of the invention, can also make some improvement and retouching, and these improvement and retouching also are regarded as within protection scope of the present invention.The content of not doing in this specification to describe in detail belongs to this area professional and technical personnel's known prior art.

Claims

One kind in the WDM-GPON system optical network unit obtain the method for wavelength value, it is characterized in that, comprise the steps:

A01. when optical line terminal does not have effective physical layer operations management maintenance message; To send " No message " to the one group of optical network unit that docks with it; The wavelength value of the transmission light signal that said one group of optical network unit need be provided with; Be filled in the reserved field of " No message ", and send to this group optical network unit;

A02. after each optical network unit in said one group of optical network unit is received " the No message " that contains wavelength value of optical line terminal transmission; Light signal according to said each optical network unit of wavelength value adjustment sends is sent to the optical line terminal that docks with this group optical network unit.
2. as claimed in claim 1 in the WDM-GPON system optical network unit obtain the method for wavelength value, it is characterized in that: said " No message " constantly sends to optical network unit and does not have the number of times restriction.
3. as claimed in claim 1 in the WDM-GPON system optical network unit obtain the method for wavelength value, it is characterized in that: said " No message " length overall is 12 bytes, and the 3rd byte to the 12 bytes are reserved field.
4. as claimed in claim 1 in the WDM-GPON system optical network unit obtain the method for wavelength value; It is characterized in that: in the said steps A 01; The wavelength value of said transmission light signal is carried out binary code, and said binary code is inserted the 3rd byte of " No message ".
5. as claimed in claim 4 in the WDM-GPON system optical network unit obtain the method for wavelength value, it is characterized in that: said wavelength value is different, its binary code is also different.
6. as claimed in claim 4 in the WDM-GPON system optical network unit obtain the method for wavelength value; It is characterized in that: after said optical network unit is received " the No message " that contains wavelength value; From the 3rd byte-extraction binary code, and according to the wavelength value that the wavelength value table of comparisons is converted into correspondence.
As claim 1 or 4 described in the WDM-GPON system optical network unit obtain the method for wavelength value; It is characterized in that: in the said steps A 02; Each optical network unit is provided with optical sender; Optical sender is regulated the light signal that will send according to said wavelength value, makes the two wavelength value consistent.
8. as claimed in claim 7 in the WDM-GPON system optical network unit obtain the method for wavelength value; It is characterized in that: in the said WDM-GPON system non-heat array wave guide grating is set, the wavelength value that requires on its wavelength channel port is identical with the wavelength value of said transmission light signal.
9. as claimed in claim 1 in the WDM-GPON system optical network unit obtain the method for wavelength value, it is characterized in that: said physical layer operations management maintenance message is observed the G.984.3 message format of standard of ITU-T.