CN104427413B - Colourless optical network unit and its implementation method - Google Patents
Colourless optical network unit and its implementation method Download PDFInfo
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- CN104427413B CN104427413B CN201310384221.9A CN201310384221A CN104427413B CN 104427413 B CN104427413 B CN 104427413B CN 201310384221 A CN201310384221 A CN 201310384221A CN 104427413 B CN104427413 B CN 104427413B
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Abstract
The present invention proposes colourless optical network unit and its implementation method.Method includes：ONU coupler receives the descending OOK optical signals from OLT, and the signal is coupled, the signal after coupling is respectively outputted into receiver and first optical splitter；ONU optical splitter is divided to input signal, by the signal output after light splitting to the delay line and next optical splitter or modulator itself connected；Wherein, the signal that the delay line of each optical splitter connection exports to the optical splitter enters line delay, and time delayed signal is re-entered into the optical splitter；ONU modulator receives the signal of last optical splitter output, and the signal is modulated, modulated signal is output into isolator；Isolator receives the signal of modulator output, outputs this signal to coupler, the signal is sent to OLT by coupler.The present invention reduces the communications cost between OLT and ONU on the premise of OLT to the ONU transmission performance of downstream signal is ensured.
Description
Technical field
The present invention relates to PON（Passive Optical Network, EPON）Technical field, more particularly to nothing
Color ONU（Optical Network Unit, optical network unit）And its implementation.
Background technology
With the development of network technology, PON technologies are to realize FTTx（Fiber to the x, intelligent acess）Main flow skill
Art, typical PON system are tree topology.PON is mainly by network by local side apparatus OLT（Optical Line Terminal,
Optical line terminal）, ustomer premises access equipment ONU and ODN（Optical Distribution Network, Optical Distribution Network）Group
Into.Wherein ODN is made up of the Passive Optical Components such as optical fiber and light point/combiner, therefore lower-cost excellent with management service
Gesture.Fig. 1 is existing WDMPON（Wavelength Division Multiplexing PON, Wave division multiplexing passive optical network）
Structural representation, wherein, AWG（Array Waveguide Gratings, array waveguide grating）For light point/combiner.
PON can be divided into PSPON by the signal method of salary distribution（Power Splitter PON, power Splittable passive optical network
Network）And WDM-PON.Current APON（ATM PON, the PON based on asynchronous transfer mode）、BPON（Broadband PON, it is wide
Band PON）、EPON（Ethernet PON, ether PON）And GPON（Gigabit PON, Gigabit-Capable PON）Belong to
PSPON, PSPON use star coupler branch, and uplink/downlink transmission uses TDMA/TDM（Time division multiple acess/time division multiplexing）Mode
Realize that channel width is shared, the signal that shunt is sent OLT by power distribution is assigned on each ONU.WDM-PON technologies
It is then that signal the various wavelength that optical branching device is sent by identifying OLT, is assigned to wavelength-division multiplex technique with pon
Each road ONU.
WDM-PON based on wavelength-division multiplex technique is identified using wavelength as user terminal ONU, real using wavelength-division multiplex technique
Existing multi-upstream access, using the teaching of the invention it is possible to provide higher bandwidth of operation, it is possible to achieve symmetrical broadband access truly.Meanwhile it is also
Many technological difficulties such as ONU ranging in TDMA technologies, fast bit synchronization can be avoided, by each between OLT and each ONU
From wavelength transmit signal, each ONU can only receive the information for issuing its own, and WDM-PON has more preferable security and can
Autgmentability.Only in medium education（MAC, Media Access Control）Layer, OLT can be controlled by single wavelength
Point to point link connection between ONU, without point-to-multipoint medium education, and each ONU can be used not
Same speed and agreement and OLT communications, so as to suffer from obvious advantage in network management and system upgrade aspect of performance.
ONU colourless property is WDM-PON and an important factor for PON technologies of future generation reduces cost.Solution main at present
Certainly scheme is as follows：
Scheme 1：Downstream wavelength from OLT to ONU uses DPSK（Differential Phase Shift Keying are poor
Divide phase-shift keying）Signal, two parts are divided into ONU sides, part input optical module receives, and another part is through SOA
（Semiconductor Optical Amplifier, semiconductor optical amplifier）Amplification, is then modulated to OOK（On-Off
Keying, on-off keying）Signal is sent to OLT as upward signal；
Scheme 2：Downstream wavelength from OLT to ONU uses OOK signals, increases the noise of Plus "0" bit, reduces disappearing for signal
Light ratio.It is divided into two parts in ONU sides, part input optical module is received, and a part is amplified through SOA under saturation gain state.
Because " 0 " bit of input signal still has the light of certain power, therefore the signal of the similar direct current light of SOA outputs, after OOK is modulated
OLT is sent to as upward signal；
Scheme 3：Each ONU configures tunable laser as upward signal light source.
The shortcomings that prior art, is as follows：
In scheme 1, descending to use dpsk signal, OLT dispensing device and ONU reception device cost are with respect to OOK signals
It is higher；
In scheme 2, descending OOK signals extinction ratio is relatively low, such as typically 5dB, and the normal downstream signal of PON system disappears
Light ratio is 10dB, downstream signal performance degradation, influences transmission performance and transmission range；
In scheme 3, each ONU configures an adjustable laser as upward signal light source, and which results in ONU
The growth of cost.Simultaneously as the wavelength that each ONU works in WDM-PON systems is different, that is to say, that laser in each ONU
The operation wavelength of device is different, thus needs to be equipped with the board of a variety of different models, increases installation and the expense safeguarded.
The content of the invention
The present invention provides colorless ONU and its implementation, with the transmission performance for the downstream signal for ensureing OLT to ONU
Under the premise of, reduce the communications cost between OLT and ONU.
The technical proposal of the invention is realized in this way：
A kind of colourless optical network unit ONU, including：Coupler, receiver, at least one optical splitter, and each optical splitter
Input, have a delay line, modulator and isolator between output end, and isolator only receives the letter from modulator direction
Number, wherein：
Coupler：The downing switch keying OOK optical signals from optical line terminal OLT are received, the signal is coupled,
Signal after coupling is respectively outputted to receiver and first optical splitter；The signal of isolator output is received, the signal is sent out
Toward OLT；
Receiver：Receive the downlink optical signal that coupler is sent；
Optical splitter：Input signal is divided, by the signal after light splitting be respectively outputted to itself connection delay line with
And next optical splitter of itself connection or the modulator of itself connection；
Delay line：The signal exported to the optical splitter of itself connection enters line delay, and the signal after delay is re-entered into certainly
The optical splitter of body connection；
Modulator：The signal of last optical splitter output is received, the signal is modulated, modulated signal is output to
Isolator；
Isolator：The signal of modulator output is received, outputs this signal to coupler.
The optical splitter is 2：2 optical splitters.
The ONU further comprises semiconductor optical amplifier SOA, and its input is connected with last optical splitter, and its is defeated
Go out end to be connected with modulator, for receiving the signal of last optical splitter output, the signal is amplified, after amplification
Signal output is to modulator.
A kind of realization method of colorless ONU, the ONU include：Coupler, receiver, at least one optical splitter, and each light splitting
There are a delay line, modulator and isolator between the input of device, output end, and isolator is only received from modulator direction
Signal, this method include：
ONU coupler receives the descending OOK optical signals from OLT, the signal is coupled, by the signal after coupling
It is respectively outputted to receiver and first optical splitter；
ONU optical splitter is divided to input signal, and the signal after light splitting is respectively outputted to the delay of itself connection
The modulator of the next optical splitter or itself connection of line and itself connection；Wherein, the delay line of each optical splitter connection
Line delay is entered to the signal of optical splitter output, the signal after delay is re-entered into the optical splitter；
ONU modulator receives the signal of last optical splitter output, and the signal is modulated, and modulated signal is defeated
Go out to isolator；
Isolator receives the signal of modulator output, outputs this signal to coupler, the signal is sent to by coupler
OLT。
The optical splitter is 2：2 optical splitters.
The ONU further comprises SOA, and its input is connected with last optical splitter, and its output end connects with modulator
Connect,
The optical splitter of the ONU by the signal after light splitting be respectively outputted to itself connection delay line and itself connection
Next optical splitter or the modulator of itself connection are：
When optical splitter is last optical splitter, the signal after light splitting is respectively outputted to itself connection by the optical splitter
Delay line and the SOA of itself connection, SOA is amplified to the signal, by the signal output after amplification to modulator；
And the modulator of the ONU receive last optical splitter output signal be：Receive last optical splitter warp
The signal exported by SOA.
It can be seen that in the present invention, OLT to ONU downlink optical signal uses the OOK signals of normal extinction ratio, ensure that transmission
Performance, meanwhile, optical splitter and delay line, isolator device are increase only, cost reduces.
Brief description of the drawings
Fig. 1 is existing WDMPON structural representation；
Fig. 2 is PON provided in an embodiment of the present invention networking schematic diagram；
Fig. 3 is the implementation method flow chart of the colorless ONU provided in an embodiment of the present invention under networking shown in Fig. 2.
Embodiment
Below in conjunction with the accompanying drawings and specific embodiment the present invention is further described in more detail.
Fig. 2 is PON provided in an embodiment of the present invention networking schematic diagram, as shown in Fig. 2 OLT and wavelength-division in the networking
Multiplexer can all use prior art to realize, the difference is that ONU composition, wherein：
Each ONU includes：Coupler 21, receiver 22, at least one optical splitter 23, and the input of each optical splitter 23,
There are a delay line 24, SOA25, modulator 26 and isolator 27 between output end, and 27 receptions of isolator come from modulator
The signal in 26 directions, the n in Fig. 2, m are positive integer, and n >=1, m >=1, optical splitter all use 2：2 optical splitters, wherein：
Coupler 21：The descending OOK optical signals from OLT are received, the signal is coupled, by the signal after coupling point
22, first optical splitters 23 of receiver and isolator 27 are not output to；The signal that isolator 27 exports is received, the signal is sent to
OLT。
Receiver 22：Receive the optical signal that coupler 21 is sent.
Optical splitter 23：Input signal is divided, the signal after light splitting is respectively outputted to the delay line of itself connection
And next optical splitter of itself connection or the SOA25 of itself connection.
Wherein, each optical splitter has two inputs and two output ends.When including multiple optical splitters in ONU, its
In, input, the output of each optical splitter are as follows respectively：
The signal exported from coupler 21 of coming of the input signal of first optical splitter, another way connect from itself
Delay line output signal, and its output signal is output to next optical splitter all the way, and another way is output to itself connection
Delay line enter line delay；
The output signal all the way from previous optical splitter of second input signal to penultimate optical splitter, separately
The output signal of delay line all the way from itself connection, output signal are output to next optical splitter all the way, and another way is defeated
The delay line gone out to itself connection enters line delay；
The output signal all the way from previous optical splitter of the input signal of last optical splitter, another way come from certainly
The output signal of the delay line of body connection, output signal are output to SOA25 all the way, and another way is output to the delay of itself connection
Line enters line delay.
Delay line 24：The signal exported to the optical splitter 23 of itself connection enters line delay, and the signal after delay re-enters
To the optical splitter 23 of itself connection.
SOA25：The signal of last optical splitter 23 output is received, the signal is amplified, by the signal after amplification
It is output to modulator 26.
Modulator 26：The signal of SOA25 outputs is received, the signal is modulated, modulated signal is output to isolator
27。
Isolator 27：The signal that modulator 26 exports is received, outputs this signal to coupler 21.
Fig. 3 be the colorless ONU provided in an embodiment of the present invention under networking shown in Fig. 2 implementation method flow chart, such as Fig. 3
Shown, it is comprised the following steps that：
Step 301：The descending OOK optical signals A that OLT is sent（t）Reach any ONU.
Step 302：ONU coupler 21 receives A（t）, to A（t）Coupled, the wherein all the way A after coupling（t）Output
To receiver 22, another way A（t）It is output to first optical splitter 23.
Figure it is seen that A（t）After the coupling of coupler 21, also all the way A（t）Isolator 27 can be output to, still
Isolator 27 only allows the signal from the direction of modulator 26 to enter, therefore, road A（t）It can be forbidden by isolator 27.
Step 303：First optical splitter 23 receives A（t）, to A（t）It is divided, obtains two-wayWherein all the wayIt is input to second optical splitter 23, another wayIt is output on the delay line 24 of first optical splitter connection, delay
Line 24 is rightτ delays are carried out, are obtainedShouldIt is input to first optical splitter 23 again, first point
Light device 23 is rightIt is divided, obtains two-wayWherein all the wayIt is output to second light splitting
Device 23, another wayIt is input on the delay line 24 of first optical splitter connection, delay line 24 is rightCarry out
τ is delayed, and obtainsShouldFirst optical splitter 23 is input to again, and first optical splitter 23 is rightIt is divided, the rest may be inferred；The course of work of each 23 connected delay line of optical splitter with first
The connected delay line of optical splitter is identical, wherein, if optical splitter 23 uses mean allocation light energy mode.
It should be noted that optical splitter 23 is set in this step uses mean allocation light energy mode, that is, the luminous energy inputted
Amount, which is averaged, to be assigned in two-way output signal；And in actual applications, optical splitter can determine to input according to actual conditions
Allocation proportion of the light energy in two-way output signal.
If optical splitter 23 uses mean allocation light energy mode, then the output B (t) of first optical splitter 23 can be calculated
For：
The output C (t) of second optical splitter 23 is：
The output D (t) of 3rd optical splitter 23 is：
The rest may be inferred, can obtain the output of follow-up each optical splitter.
Step 304：SOA25 receives the output signal of last optical splitter, the signal is amplified, after amplification
Signal output is modulated to modulator 26, and modulated signal is output to isolator 27 by modulator 26, and isolator 27 is by the signal
Coupler 21 is output to, the signal is sent to OLT by coupler 21.
As can be seen from Figure 3：The downlink optical signal A (t) that OLT is sent after being divided, be delayed, be superimposed repeatedly, optical signal
Optical signal close to direct current is shaped as by light pulse signal, and ' 0 ' bit is provided with certain luminous power；This passes through shaping afterwards
Optical signal be amplified by SOA, and SOA is operated in saturation interval, therefore optical signal passes through further shaping, closer
Direct current light, and keep original wavelength.And the downlink optical signal that OLT is sent is the OOK signals of normal extinction ratio, transmission performance
It is unaffected；In addition, the present invention is relatively low only with optical splitter and delay line, cost.
The foregoing is merely illustrative of the preferred embodiments of the present invention, is not intended to limit the invention, all essences in the present invention
God any modification, equivalent substitution and improvements done etc., should be included within the scope of protection of the invention with principle.
Claims (4)
- A kind of 1. colourless optical network unit ONU, it is characterised in that including：Coupler, receiver, at least one optical splitter, and often There are a delay line, modulator and isolator between the input of individual optical splitter, output end, and isolator is only received from modulator The signal in direction, wherein：Coupler：The downing switch keying OOK optical signals from optical line terminal OLT are received, the signal are coupled, by coupling Signal after conjunction is respectively outputted to receiver and first optical splitter；The signal of isolator output is received, the signal is sent to OLT；Receiver：Receive the downlink optical signal that coupler is sent；Optical splitter：Input signal is divided, by the signal after light splitting be respectively outputted to itself connection delay line and from Next optical splitter of body connection or the modulator of itself connection；Delay line：The signal exported to the optical splitter of itself connection enters line delay, and the signal after delay is re-entered into itself and connected The optical splitter connect；Modulator：The signal of last optical splitter output is received, the signal is modulated, modulated signal is output to isolation Device；Isolator：The signal of modulator output is received, outputs this signal to coupler；The ONU further comprises semiconductor optical amplifier SOA, and its input is connected with last optical splitter, its output end It is connected with modulator, for receiving the signal of last optical splitter output, the signal is amplified, by the signal after amplification It is output to modulator.
- 2. ONU according to claim 1, it is characterised in that the optical splitter is 2：2 optical splitters.
- 3. a kind of realization method of colorless ONU, it is characterised in that the ONU includes：Coupler, receiver, at least one optical splitter, And each have a delay line, modulator and isolator between the input of optical splitter, output end, and isolator only receives and carrys out self-regulated The signal in device direction processed, this method include：ONU coupler receives the descending OOK optical signals from OLT, and the signal is coupled, and the signal after coupling is distinguished It is output to receiver and first optical splitter；ONU optical splitter is divided to input signal, by the signal after light splitting be respectively outputted to itself connection delay line with And next optical splitter of itself connection or the modulator of itself connection；Wherein, the delay line of each optical splitter connection is to this The signal of optical splitter output enters line delay, and the signal after delay is re-entered into the optical splitter；ONU modulator receives the signal of last optical splitter output, and the signal is modulated, modulated signal is output to Isolator；Isolator receives the signal of modulator output, outputs this signal to coupler, the signal is sent to OLT by coupler；The ONU further comprises SOA, and its input is connected with last optical splitter, and its output end is connected with modulator,Signal after light splitting is respectively outputted to the delay line of itself connection and itself connected next by the optical splitter of the ONU Individual optical splitter or the modulator of itself connection are：When optical splitter is last optical splitter, the signal after light splitting is respectively outputted to the delay of itself connection by the optical splitter Line and the SOA of itself connection, SOA is amplified to the signal, by the signal output after amplification to modulator；And the modulator of the ONU receive last optical splitter output signal be：Receive last optical splitter via The signal of SOA outputs.
- 4. according to the method for claim 3, it is characterised in that the optical splitter is 2：2 optical splitters.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2004061512A1 (en) * | 2002-12-18 | 2004-07-22 | Hrl Laboratories, Llc | Recursive optical delay-line filter with bipolar taps |
| CN101251392A (en) * | 2008-04-11 | 2008-08-27 | 东南大学 | Optical circuit apparatus for detecting destabilization of complete optical fiber wind-field vibrating sensing network system |
| CN102231864A (en) * | 2011-06-20 | 2011-11-02 | 东南大学 | Optical-codeword-label-based optical packet multicast transmission and receiving methods and devices |
| CN102377725A (en) * | 2011-12-07 | 2012-03-14 | 东南大学 | OFDM (Orthogonal Frequency Division Multiplexing) sub-carrier-based optical label processing method and optical packet switching method |
| CN103123739A (en) * | 2012-12-05 | 2013-05-29 | 北京航天易联科技发展有限公司 | Test apparatus for signal processing unit of optical fiber perimeter intrusion alarm system |
-
2013
- 2013-08-29 CN CN201310384221.9A patent/CN104427413B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2004061512A1 (en) * | 2002-12-18 | 2004-07-22 | Hrl Laboratories, Llc | Recursive optical delay-line filter with bipolar taps |
| CN101251392A (en) * | 2008-04-11 | 2008-08-27 | 东南大学 | Optical circuit apparatus for detecting destabilization of complete optical fiber wind-field vibrating sensing network system |
| CN102231864A (en) * | 2011-06-20 | 2011-11-02 | 东南大学 | Optical-codeword-label-based optical packet multicast transmission and receiving methods and devices |
| CN102377725A (en) * | 2011-12-07 | 2012-03-14 | 东南大学 | OFDM (Orthogonal Frequency Division Multiplexing) sub-carrier-based optical label processing method and optical packet switching method |
| CN103123739A (en) * | 2012-12-05 | 2013-05-29 | 北京航天易联科技发展有限公司 | Test apparatus for signal processing unit of optical fiber perimeter intrusion alarm system |
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