CN105743601A - Symmetrical TWDM-PON (Time and Wavelength Division Multiplexing Passive-Optical Network) system capable of realizing high-speed transmission through low-speed optical device - Google Patents
Symmetrical TWDM-PON (Time and Wavelength Division Multiplexing Passive-Optical Network) system capable of realizing high-speed transmission through low-speed optical device Download PDFInfo
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- CN105743601A CN105743601A CN201610066452.9A CN201610066452A CN105743601A CN 105743601 A CN105743601 A CN 105743601A CN 201610066452 A CN201610066452 A CN 201610066452A CN 105743601 A CN105743601 A CN 105743601A
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04J—MULTIPLEX COMMUNICATION
- H04J14/00—Optical multiplex systems
- H04J14/02—Wavelength-division multiplex systems
- H04J14/0227—Operation, administration, maintenance or provisioning [OAMP] of WDM networks, e.g. media access, routing or wavelength allocation
- H04J14/0238—Wavelength allocation for communications one-to-many, e.g. multicasting wavelengths
- H04J14/0239—Wavelength allocation for communications one-to-many, e.g. multicasting wavelengths in WDM-PON sharing multiple downstream wavelengths for groups of optical network units [ONU], e.g. multicasting wavelengths
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
- H04B10/25—Arrangements specific to fibre transmission
- H04B10/2507—Arrangements specific to fibre transmission for the reduction or elimination of distortion or dispersion
- H04B10/2513—Arrangements specific to fibre transmission for the reduction or elimination of distortion or dispersion due to chromatic dispersion
- H04B10/25133—Arrangements specific to fibre transmission for the reduction or elimination of distortion or dispersion due to chromatic dispersion including a lumped electrical or optical dispersion compensator
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
- H04B10/50—Transmitters
- H04B10/501—Structural aspects
- H04B10/503—Laser transmitters
- H04B10/504—Laser transmitters using direct modulation
Abstract
The invention discloses a symmetrical TWDM-PON (Time and Wavelength Division Multiplexing Passive-Optical Network) system capable of realizing high-speed transmission through a low-speed optical device, and relates to the field of optical fiber communication. The system comprises an OLT (Optical Line Terminal), an optical remote node and a plurality of ONUs (Optical Network Unit), wherein one end of the optical remote node is connected to the OLT through a feeder type optical fiber, and the other end of the optical remote node is connected to the ONUs through a plurality of distributed optical fibers; the OLT comprises a first medium control module, a downlink data transmitting module, a first optical wavelength division multiplexer and an uplink data receiving module; and each ONU comprises a third optical wavelength division multiplexer, a downlink data receiving module, a second medium control module and an uplink data transmitting module. According to the system, the cost of the system can be remarkably reduced, the complexity of the system is effectively reduced, and the difficulty in high-speed real-time data transmission of the system is reduced.
Description
Technical field
The present invention relates to fiber optic communication field, be specifically related to one low speed optical device and realize
The symmetrical TWDM-PON system of high-speed transfer.
Background technology
Along with country widelys popularize " the Internet+" policy, the Internet will welcome a new round
High speed development, meanwhile communication data traffic also can quickly increase, and optic communication is as transmission
The main flow of net, the important component part of access network, its capacity requirement will constantly promote development.
Moreover, Global Internet number of users is skyrocketed through.Under such a overall situation,
ITU-T(International Telecommunication Union Telecommunication
Standardization Sector, ITU Telecommunication Standardization Sector) tissue and IEEE
(Institute of Electrical and Electronics Engineers, electric electronic engineering Shi Xue
Meeting) tissue all started the standard discussion of respective New Generation Optical access network.From 2012,
(Full Service Access Networks, FSAN is discussed for ITU-T tissue and FSAN
Altar) tissue proceeds by NG PON2 (Next Generation Passive Optical Network
2, next-generation passive optical network) correlational study and standard formulation, and IEEE organize right
NG-EPON (Next Generation Ethernet Passive Optical Network, of future generation
Ethernet passive optical network) discussion also have begun to.
2012, FSAN organized TWDM-PON (Time and Wavelength
Division Multiplexing PON, time-division Wave division multiplexing passive optical network) system elects as
The preferred version of NG-PON2.On the one hand, this system is based on wave stack scheme, technology phase
To maturation；On the other hand, this system still continues to use optical distribution network based on the unrelated optical branching device of wavelength
Network, supports backward compatibility.Based on above-mentioned advantage, this system is in the structure of TWDM-PON
There is also preferable application prospect.
How realizing low cost High Speed Modulation is the significant challenge during TWDM-PON realizes.Four
The 100G TWDM-PON of wave stack requires that Single wavelength speed is up to 25Gb/s, and current
Conventional commercial devices bandwidth is at about 10GHz.How to use low cost device and simple skill
Art realizes Single wavelength 25Gb/s and above modulation and supports that the fiber-optic transfer of more than 40km is
Need the problem that emphasis considers, mainly include following two aspect for the research of this problem:
On the one hand: relate to device and prepare, realized at a high speed by high-speed modulator and broadband receiver
Modulation and reception；Low cost is realized based on mixing silicon, III/V race material it has been reported that utilize
The directly modulated lasers of 20Gb/s modulation rate can be supported；How to improve receiver bandwidth also simultaneously
It is widely studied.
On the other hand: utilize high order modulation pattern to reduce launching and the bandwidth requirement of receiver.
Part related work has been had to deliver at present.Finding through retrieval, 2014, Huawei Technologies had
Limit company is in fiber optic communication meeting (Optical Fiber Communication Conference)
Deliver entitled " 30km Downstream Transmission Using 4 × 25Gb/s 4-PAM
Modulation with Commercial 10Gbps TOSA and ROSA for
100Gb/s-PON " (4 × 25Gb/s 4-PAM signal based on commercial 10Gb/s transceiving device
30 km transmission) article.This article is recorded below scheme: utilize commercial 10Gbps
Device realizes 4-PAM, and (4 Pulse Amplitude Modulation, four level pulse amplitudes are adjusted
System) modulation and demodulation of Single wavelength 25Gb/s signal of form.4-PAM modulation format is one
Planting Multilevel modulation, four kinds of pulse amplitudes can represent two bits, makes the baud rate of signal drop
The low half for binary format such that it is able to reduce the bandwidth demand to transceiver.This article
In the major defect of scheme be: do not account for dispersion in area of light, so causing follow-up DSP
(Digital Signal Processing, Digital Signal Processing) processes relative complex, and system is imitated
Fruit is the most not satisfactory.
In addition to 4-PAM, duobinary modulation is also a kind of conventional modulation system.Double two enter
Code processed belongs to a kind of correlative coding technology, utilizes the dependency between bit, by the telecommunications of two level
Number transfer three level to.Correlative coding is generally realized by two ways: 1-bit postpones to be added or simulation
Low-pass filtering.Low pass filter is generally selected Bessel type, and three dB bandwidth is about signal bandwidth
1/4.Therefore, the spectrum efficiency of duobinary code improves nearly four times than two level, same rate
Duobinary system resisting chromatic dispersion ability is higher.
Finding through retrieval, the D.Van Veen of Alcatel-Lucent company etc. was in 2014
Europe optical-fibre communications exhibition (European Conference on Optical
Communication) entitled " 26-Gbps PON Transmission over 40-km has been delivered on
using Duo-binary Detection with a Low Cost 7-GHz APD-Based
Receiver " (utilize the 26-Gb/s duobinary signal that 7GHz APD receiver realizes
40km transmit) article, in this article propose below scheme: in ONU end, utilize 7GHz
The receiver of bandwidth, it is achieved the duobinary system of 26Gb/s signal receives, and enters subsequently through double two
System is demodulated to binary demodulation circuit.The major defect of the program is: although reducing
The bandwidth of receiver, but transmitting terminal remains a need for wideband modulator；And signal wavelength is at O ripple
Section, this wave band abbe number is the lowest, and therefore the program does not accounts for chromatic dispersion problem.
2015, D.Van Veen etc. was at IEEE Journal of Lightwave Technology
Another entitled " Demonstration of 40-Gb/s has been delivered on (" lightwave technology magazine ")
TDM-PON Over 42-km With 31 dB Optical Power Budget Using an
APD-Based Receiver " (31-dB power budget based on APD receiver and 42km
Fiber-optic transfer 40Gb/s time-division multiplex passive optical network system demonstration) article, this article
Middle proposition below scheme: utilize narrow band modulator, it is achieved high speed Duo-binary (duobinary system
Pattern) modulation, transmitting terminal passes through low pass filter, and by OOK, (On-Off Keying, opens
Close keying) be converted to Duo-binary pattern.But, the receiving terminal in the program remains a need for width
Band receiver.This article demonstrates the 40-Gb/s signal 26km difference distance at C-band
Fiber-optic transfer.Although have employed the external modulation mode that chirp coefficient is less, but, for difference
Transmission range, need to compensate different dispersion measures, concrete implementation process is the most complicated.
Under conditions of low complex degree, realize modulated in real time and the solution of high speed signal with low speed devices
Tune is problem demanding prompt solution in optical access network of future generation.Existing scheme or employing high speed device
Realizing high-speed transfer, system cost is the highest；Substantial amounts of dependence Digital Signal Processing, drastically
Increase the complexity that follow-up data process, substantially cannot realize the real time execution of system.
Summary of the invention
The invention aims to overcome the deficiency of above-mentioned background technology, it is provided that a kind of with low
Speed optical device realizes the symmetrical TWDM-PON system of high-speed transfer, it is possible to significantly reduces and is
The cost of system, effectively reduces the complexity of system, reduces the difficulty of system high-speed real-time transmission data
Degree.
The present invention provides a kind of low speed optical device to realize the symmetry of high-speed transfer
TWDM-PON system, including optical line terminal OLT, branched system optical fiber, light far-end joint
Point, some distribution type fiber-optics and some optical network unit ONU, light distant-end node is positioned at OLT
With between ONU, one end of light distant-end node connects OLT by branched system optical fiber, another
Holding and connect some ONU by some distribution type fiber-optics, distribution type fiber-optic is with ONU one by one
It is corresponding, it is characterised in that: described OLT includes the first media control module, descending
Data transmission module, the first light wavelength division multiplexing and upstream data receiver module, OLT's
Shared first light wavelength division multiplexing, the first media control module up, descending；Under
Line direction, the first media control module, downlink data transmitter module, the first light wave
Division multiplexer is sequentially connected with；Up direction, the first light wavelength division multiplexing, upstream data connect
Receive module, the first media control module is sequentially connected with；
Downlink data transmitter module includes that multiple directly modulated lasers, a second smooth wavelength-division are multiple
With device, a periodicity optical filter and first image intensifer, all straight tune laser
One end of device is connected with the first media control module, and the other end and the second smooth wavelength-division are multiple
With device be connected, the second light wavelength division multiplexing, periodically optical filter, the first image intensifer,
First light wavelength division multiplexing is sequentially connected；
Upstream data receiver module include second image intensifer, one there is fixing color
Dissipate dispersion compensation device, a light Wave decomposing multiplexer and multiple up photodetection of amount
Device, the quantity of row photodetectors is identical with the quantity of directly modulated lasers, the first light wave
Division multiplexer, the second image intensifer, there is the dispersion compensation device of fixing dispersion measure, light
Wave decomposing multiplexer is sequentially connected, one end of all row photodetectors and light Wave Decomposition
Multiplexer is connected, and the other end and the first media control module are connected；
Each ONU include the 3rd light wavelength division multiplexing, downlink data receiver module, second
Media control module and upstream data transmitter module, ONU's is up, descending common
By the 3rd light wavelength division multiplexing, the second media control module, down direction, the 3rd
Light wavelength division multiplexing, downlink data receiver module, the second media control module are sequentially
Connect；Up direction, the second media control module, upstream data transmitter module,
3rd light wavelength division multiplexing is sequentially connected with.
On the basis of technique scheme, described upstream data transmitter module includes low speed
Electroabsorption Modulated Laser EML, this low speed EML have tunable wave length characteristic, are used for
The upward signal sending the second media control module carries out four level pulse amplitudes and adjusts
System.
On the basis of technique scheme, described downlink data receiver module includes adjustable
Optical filter, row photodetectors, the 3rd light wavelength division multiplexing, tunable optical filter,
Row photodetectors, the second media control module are sequentially connected.
The first media on the basis of technique scheme, in down direction, OLT
Medium control module controls generation and the process of downstream signal, and downstream signal is modulated institute
Have on the light carrier that directly modulated lasers produces；Each directly modulated lasers produces light carrier, simultaneously
The corresponding signal of telecommunication is modulated on this light carrier, form downstream signal and send；Second light
The downstream signal that all directly modulated lasers are sent by wavelength division multiplexer carries out multiplexing process, will
Downstream signal after multiplexing issues periodically optical filter；Periodically optical filter is to multiplexing
After downstream signal be filtered, it is achieved the frequency equilibrium of downstream signal and chirp management,
Filtered downstream signal is sent to the first image intensifer；First image intensifer is to filtering
After downstream signal be amplified, will amplify after downstream signal be sent to the first smooth wavelength-division
Multiplexer；The downstream signal that first image intensifer amplifies is passed through by the first light wavelength division multiplexing
Branched system fiber-optic transfer is to light distant-end node, under light distant-end node is incited somebody to action by distribution type fiber-optic
Row signal is transferred to each ONU；
Downstream signal is transferred to downlink data and connects by the 3rd light wavelength division multiplexing in each ONU
Receive module；Downstream signal is filtered by the tunable optical filter in downlink data receiver module
Ripple, obtains the optical signal of Single wavelength；The optical signal of Single wavelength is turned by row photodetectors
Becoming the signal of telecommunication, be transferred to the second media control module, the second media controls
Module is transferred to customer side after processing the signal of telecommunication received；Second media control
Molding block, always according to control protocol, controls the reception of downstream signal, major control tunable optical
The centre wavelength of wave filter and the time slot of downstream signal reception.
The second matchmaker on the basis of technique scheme, in up direction, each ONU
Body medium control module, according to control protocol, controls the generation of upward signal, upstream data
The transmitting wavelength of transmitter module and the time slot of transmission, by the uplink signal transmissions of generation to upper
Low speed EML in row data transmission module, low speed EML control mould to the second media
The upward signal that block is sent carries out four level pulse amplitude modulation(PAM)s, will be through four level pulses
The uplink signal transmissions of amplitude modulation(PAM) is to the 3rd light wavelength division multiplexing；3rd OWDM
Device will be arrived through the uplink signal transmissions of four level pulse amplitude modulation(PAM)s by distribution type fiber-optic
Light distant-end node, the wavelength of the upward signal in different ONU is tuned as required,
Operation wavelength is identical or different；Light distant-end node is upper to the different wave length that each ONU transmits
Row signal couples, then the uplink signal transmissions after coupling is arrived by branched system optical fiber
OLT；
The first light wavelength division multiplexing in OLT by uplink signal transmissions to the second light amplification
Device；Second image intensifer amplifies upward signal；There is the dispersion compensator of fixing dispersion measure
Part carries out dispersion compensation to upward signal, and the dispersion measure that all up channels are corresponding keeps one
Cause；Upward signal is demultiplexed by light Wave decomposing multiplexer, up by different wave length
Signal is transferred to corresponding row photodetectors；Up light is believed by row photodetectors
Number it is changed into the signal of telecommunication, then this signal of telecommunication is transferred to the first media control module；
First media control module receives the signal of telecommunication that row photodetectors is sent, and right
The signal of telecommunication received carries out four level conversion process to two level.
On the basis of technique scheme, downlink datas different in described OLT is launched
Module has different transmitting wavelength, the different wavelength between downlink data transmitter module
Interval meets the standard of ITU-T；Wavelength interval between down channel is periodically light filter
The integral multiple of the free spectrum intervals of ripple device, i.e. downstream signal spectrum are positioned at periodically light filter
At the same position of ripple device spectral pattern: rising edge or trailing edge；Periodically optical filter
Free spectrum intervals is tunable.
On the basis of technique scheme, all row photodetectors, descending photoelectricity
Detector is low speed normal light electric explorer.
On the basis of technique scheme, described smooth distant-end node is 1:N by splitting ratio
Light branch/combiner composition, N takes 64,128 or 256.
On the basis of technique scheme, described directly modulated lasers has tunable wave length
Characteristic, its tunable wave length characteristic is controlled by temperature or electric current.
On the basis of technique scheme, described in there is the dispersion compensation of fixing dispersion measure
Device includes chirp grating, Fiber Bragg Grating FBG, dispersion compensating fiber.
Straight tune on the basis of technique scheme, in described downlink data transmitter module
The a width of 10GHz of band of laser instrument.
On the basis of technique scheme, up in described upstream data receiver module
Photodetector uses PIN type light electric explorer, carries a width of 10GHz, and by letter
Four level signals are changed into two level signals by single decision circuit, it is achieved the reality of upstream data
Time process.
On the basis of technique scheme, the band of described downlink data receiver module is a width of
10GHz。
On the basis of technique scheme, described upstream data transmitter module has at least
10Gb/s data modulation could power, has tunable wave length function simultaneously, in order to realize ONU
Decolorizable, according to actual needs, the data of different ONU are modulated required ripple
In length.
On the basis of technique scheme, described OLT has the color of fixing dispersion measure
Dispersion compensator part is used for: compensate up 25Gbps tetra-level pulse am signals, its
Group delay is periodically variable with wavelength change；The dispersion measure of this dispersion compensation device is
-650ps/nm。
On the basis of technique scheme, this system realizes signal transmission distance 0～40km
Seamless coverage.
Compared with prior art, advantages of the present invention is as follows:
(1) low cost: the present invention utilizes the filter action of single optical filter, it is achieved under to
The frequency equilibrium (Frequency Equalization) of row signal and chirp management (Chirp
Management)；Utilize the dispersion compensation device that single dispersion measure is fixing, it is achieved to transmission not
The dispersion compensation of same distance upward signal, it is possible to significantly reduce the cost of system.
(2) backward compatible: the present invention has well in occasions such as access network, short distance interconnections
Backward compatibility, in traditional 10Gb/s system, it is not necessary to change the framework of existing system,
Can be achieved with the High Speed Modulation of 25Gb/s, it is achieved smooth upgrading.
(3) high speed real-time Transmission: the straight straightening of the descending employing of the present invention is examined, upward signal is launched
Using directly modulation, receiving terminal is only used four level and is turned two level logic circuits, it is not necessary to extra
Digital Signal Processing, it is possible to effectively reduce the complexity of system, reduce system high-speed and pass in real time
The difficulty of transmission of data.
(4) present invention combines single optical filter and optical signal high order modulation realizes backward compatible
Symmetrical TWDM-PON system, it is possible to utilize arrowband directly modulated lasers and narrow-band reception device
Realize High Speed Modulation based on binary system pattern and demodulation, it is achieved the downlink transfer of signal；Can
Reasonably use optical dispersion compensation device, in conjunction with high order modulation, it is achieved the uplink of signal,
Greatly reduce system cost, promote the development of symmetrical TWDM-PON.
(5) at up aspect, it is different from existing a large amount of dependence digital signal processed offline skill
Art, the present invention at receiving terminal by having the dispersion compensation device of fixing dispersion measure, light Wave Decomposition
Multiplexer and multiple row photodetectors, it is achieved up multiple wavelength, different transmission range
High-quality receives, the real-time reception of four level pulse amplitude modulation(PAM) (4-PAM) signals.
(6) at descending aspect, it is different from existing high order modulation technique, the present invention uses
Binary system is adjusted to form, it is to avoid use complicated reception circuit at optical network unit, it is possible to fall
The reception cost of low user side.
(7) present invention is capable of symmetrical 4*25Gbps based on 10GHz narrowband device speed
The C-band muting sensitivity damage 40km fiber-optic transfer of rate signal.
Accompanying drawing explanation
Fig. 1 is the symmetry realizing high-speed transfer in the embodiment of the present invention with low speed optical device
The structural representation of TWDM-PON system.
Fig. 2 is group delay and the wavelength graph of the dispersion compensation device with fixing dispersion measure.
Fig. 3 is the dispersion compensation device added in up-link and have fixing dispersion measure, is leaning against
Eye pattern under back of the body situation.
Fig. 4 is the dispersion compensation device added in up-link and have fixing dispersion measure, in transmission
Eye pattern under 20km situation.
Fig. 5 is the dispersion compensation device added in up-link and have fixing dispersion measure, in transmission
Eye pattern under 40km situation.
Fig. 6 is the dispersion compensation device being not added with in up-link having fixing dispersion measure, in transmission
Eye pattern under 20km situation.
After Fig. 7 is periodically optical filter free transmission range, primary signal and the filtering of filtered device
Flashlight spectrogram.
Fig. 8 is the signal after filtering eye pattern under back-to-back situation in downlink.
Fig. 9 is the signal after filtering eye pattern after transmission 40km optical fiber in downlink.
Figure 10 is the signal the most filtered in downlink eye pattern after transmission 40km optical fiber.
Detailed description of the invention
Below in conjunction with the accompanying drawings and specific embodiment the present invention is described in further detail.
Shown in Figure 1, the embodiment of the present invention provides one low speed optical device to realize at a high speed and passes
Defeated symmetrical TWDM-PON system, including OLT (Optical Line Terminal, light
Road terminal), branched system optical fiber, light distant-end node, some distribution type fiber-optics and some ONU
(Optical Network Unit, optical network unit), light distant-end node is positioned at OLT and ONU
Between, one end of light distant-end node connects OLT by branched system optical fiber, if the other end passes through
Dry distribution type fiber-optic connects some ONU, distribution type fiber-optic and ONU one_to_one corresponding.
OLT includes the first media control module, downlink data transmitter module, the first light
Wavelength division multiplexer and upstream data receiver module, the up, descending of OLT shares the first light wave
Division multiplexer, the first media control module；Down direction, the first media controls mould
Block, downlink data transmitter module, the first light wavelength division multiplexing are sequentially connected with；Up direction, the
One light wavelength division multiplexing, upstream data receiver module, the first media control module sequentially connect
Connect.Downlink data transmitter module includes multiple directly modulated lasers, second OWDM
Device, a periodicity optical filter and first image intensifer, all directly modulated lasers
One end is connected with the first media control module, the other end and the second light wavelength division multiplexing phase
Even, the second light wavelength division multiplexing, periodically optical filter, the first image intensifer, the first light
Wavelength division multiplexer is sequentially connected.Upstream data receiver module include second image intensifer,
One has the dispersion compensation device of fixing dispersion measure, a light Wave decomposing multiplexer and multiple
Row photodetectors, the quantity phase of the quantity of row photodetectors and directly modulated lasers
Mend with, the first light wavelength division multiplexing, the second image intensifer, the dispersion with fixing dispersion measure
Repay device, light Wave decomposing multiplexer is sequentially connected, one end of all row photodetectors with
Light Wave decomposing multiplexer is connected, and the other end and the first media control module are connected.
Each ONU includes the 3rd light wavelength division multiplexing, downlink data receiver module, the second matchmaker
Body medium control module and upstream data transmitter module, the up, descending of ONU shares the
Three light wavelength division multiplexings, the second media control module, down direction, the 3rd smooth wavelength-division is multiple
It is sequentially connected with by device, downlink data receiver module, the second media control module；Up side
To, the second media control module, upstream data transmitter module, the 3rd light wavelength division multiplexing
It is sequentially connected with.Upstream data transmitter module includes low speed EML (Eroabsorption
Modulated Laser, Electroabsorption Modulated Laser), this low speed EML has Wavelength tunable
Humorous characteristic, carries out four level arteries and veins for the upward signal sending the second media control module
Rush amplitude modulation(PAM) (4-PAM).Downlink data receiver module includes tunable optical filter, descending
Photodetector, the 3rd light wavelength division multiplexing, tunable optical filter, descending photodetection
Device, the second media control module are sequentially connected.
Down direction: the first media control module in OLT controls the product of downstream signal
Life and process, modulate downstream signal on the light carrier that all directly modulated lasers produce；Respectively
Directly modulated lasers produces light carrier, modulates on this light carrier by the corresponding signal of telecommunication simultaneously,
Form downstream signal；The descending letter that all directly modulated lasers are sent by the second light wavelength division multiplexing
Number carry out multiplexing process, the downstream signal after multiplexing is issued periodically optical filter；Cycle
Downstream signal after multiplexing is filtered by property optical filter, it is achieved the frequency of downstream signal is equal
Weighing apparatus and chirp management, the effect i.e. filtered includes two aspects: frequency equilibrium and pipe of warbling
Reason；Filtered downstream signal is sent to the first image intensifer；First image intensifer is to filter
Downstream signal after ripple is amplified, and the downstream signal after amplifying is sent to the first smooth wavelength-division
Multiplexer；The downstream signal that first image intensifer is amplified by the first light wavelength division multiplexing is by feedback
Wire type fiber-optic transfer is to light distant-end node, and light distant-end node passes through distribution type fiber-optic by descending letter
Number it is transferred to each ONU；Downstream signal is transmitted by the 3rd light wavelength division multiplexing in each ONU
To downlink data receiver module；Tunable optical filter in downlink data receiver module is to descending
Signal is filtered, and obtains the optical signal of Single wavelength；Row photodetectors is by Single wavelength
Optical signal is changed into the signal of telecommunication, is transferred to the second media control module, and the second media are situated between
Matter control module is transferred to customer side after processing the signal of telecommunication received；Second media are situated between
Matter control module, always according to control protocol, controls the reception of downstream signal, and major control is adjustable
The centre wavelength of optical filter and the time slot of downstream signal reception.
Up direction: the second media control module in each ONU according to control protocol,
Control the generation of upward signal, upstream data transmitter module launch wavelength and transmission time
Gap is by the low speed EML in the uplink signal transmissions of generation to upstream data transmitter module, low
Speed EML carries out four level pulse width to the upward signal that the second media control module is sent
Degree modulation (4-PAM), will be through the up letter of four level pulse amplitude modulation(PAM)s (4-PAM)
Number it is transferred to the 3rd light wavelength division multiplexing；3rd light wavelength division multiplexing will be through by distribution type fiber-optic
Cross the uplink signal transmissions of four level pulse amplitude modulation(PAM)s (4-PAM) to light distant-end node, no
Can be tuned as required with the wavelength of the upward signal in ONU, operation wavelength can be identical
Or it is different；Light distant-end node carries out coupling to the upward signal of the different wave length that each ONU transmits
Close, then by branched system optical fiber by the uplink signal transmissions after coupling to OLT；In OLT
First light wavelength division multiplexing by uplink signal transmissions to the second image intensifer；Second image intensifer
Amplify upward signal；The dispersion compensation device with fixing dispersion measure carries out color to upward signal
Dissipate and compensate, in order to process while realizing multi-wavelength signals, the color that all up channels are corresponding
Scattered amount should keep consistent；Upward signal is demultiplexed by light Wave decomposing multiplexer, by difference ripple
Long uplink signal transmissions is to corresponding row photodetectors；Row photodetectors is by upper
Traveling optical signal is changed into the signal of telecommunication, then this signal of telecommunication is transferred to the first media control mould
Block；First media control module receives the signal of telecommunication that row photodetectors is sent, and
The signal of telecommunication received is carried out four level conversion process to two level.
The dispersion compensation device with fixing dispersion measure is the dispersion compensation that a kind of dispersion measure is fixed
Device, such as: chirp grating, FBG (Fiber Bragg Grating, Fiber Bragg Grating FBG),
DCF (dispersion compensation fiber, dispersion compensating fiber) etc..
Directly modulated lasers has tunable wave length characteristic, and its tunable wave length characteristic can be passed through
Temperature or electric current control, and changing the most basic method of wavelength is that to change the chamber of laser instrument long, this
Place is through expanding with heat and contract with cold or the chamber of electroluminescent refraction index changing laser instrument is long.
Downlink data transmitter modules different in OLT has different transmitting wavelength, different
Wavelength interval between downlink data transmitter module meets the standard of ITU-T, such as: wavelength
It is set to 100GHz.In order to realize processing while multi-wavelength signals, down channel it
Between wavelength interval should be the integral multiple of the periodically free spectrum intervals of optical filter, be
Realizing multi-wavelength signals to process, downstream signal spectrum is positioned at periodically optical filter spectrum simultaneously
At the same position of type (rising edge or trailing edge)；The periodically free frequency spectrum of optical filter
Interval is tunable.
All row photodetectors, row photodetectors are the common photodetection of low speed
Device.
Light distant-end node can be by light branch/combiner (Splitter) group that splitting ratio is 1:N
Becoming, N takes 64,128 or 256.
The core concept of the present invention is: descending, utilizes optical filter technology to being modulated to arrowband
High speed signal on device carries out frequency equilibrium and chirp management, it is achieved thereby that based on
25Gbps OOK (the On-Off of 10GHz arrowband directly modulated lasers and 10GHz narrow-band receiver
Keying, on-off keying) directly modulation of signal, directly detection and the downlink transfer of 40km；
Up, utilize the feature that high order modulation high spectrum utilization and signal are warbled, it is achieved base
In 10GHz arrowband Electroabsorption Modulated Laser (EML) and 10GHz narrow-band receiver
The directly modulation of 25Gbps 4-PAM signal and the uplink of 40km.
Symmetrical below by a low cost based on 10GHz optical device transmission high speed signal
It is described in detail as a example by TWDM-PON system.
The up-downgoing Single wavelength transfer rate of this system is 25Gbps, and four wavelength transmit simultaneously
Realize symmetrical TWDM-PON system, shown in Figure 1, this TWDM-PON system bag
Include OLT, branched system optical fiber, light distant-end node, some distribution type fiber-optics and some ONU,
Wherein, one end of branched system optical fiber is connected with OLT, and the other end of branched system optical fiber connects light
Distant-end node, the two ends of distribution type fiber-optic connect light distant-end node and ONU, light far-end respectively
Node be splitting ratio be the light branch/combiner of 1:N, N takes 64,128 or 256, its tool
Body value needs the optical power budget of transmission range and the system considering in system.Light branch/
Combiner (Splitter) by distribution type fiber-optic connect ONU1, ONU2,
ONU3、……、ONUN。
Fig. 1 has 4 directly modulated lasers, 4 row photodetectors, it is possible to realize low one-tenth
Originally, the TWDM-PON system of high performance symmetrical 4 × 25G；In like manner, when directly adjusting laser
When device, row photodetectors are 2, it is possible to realize low cost, high performance symmetrical 2
The TWDM-PON system of × 25G；When directly modulated lasers, row photodetectors are
When 10, it is possible to realize low cost, the TWDM-PON of high performance symmetrical 10 × 25G
System.
The descending output port of 4 directly modulated lasers is all connected under the second light wavelength division multiplexing
Row input port, the descending output port of the second light wavelength division multiplexing is connected to periodically light filter
The descending output port of the descending input port of ripple device, periodically optical filter is connected to first
The descending input port of image intensifer, the descending output port coupling of the first light wavelength division multiplexing
In branched system optical fiber.
The a width of 10GHz of band of the directly modulated lasers in downlink data transmitter module；Upstream data
Row photodetectors in receiver module uses PIN (Positive Intrinsic Negative
Diode, photodiode) type light electric explorer, carry a width of 10GHz, and by simple
Four level signals are changed into two level signals by decision circuit, it is achieved the real-time place of upstream data
Reason.
OLT has the dispersion compensation device of fixing dispersion measure for: compensate up 25Gbps
Four level pulse am signals, its group delay is shown in Figure 2 with wavelength curve, can
To see that its group delay is periodically variable with wavelength change.Owing to wavelength is asked by group delay
Leading is exactly the dispersion measure of signal, figure it is seen that the dispersion measure of this dispersion compensation device
It is about-650ps/nm.Fig. 3, Fig. 4, Fig. 5 are to add this dispersion compensation at receiving terminal respectively
Device, back-to-back, transmits 20km, the eye pattern transmitted under 40km situation, it can be seen that three
Individual eye pattern is four level eye-diagram opened, thus illustrates that the program can realize signal transmission
The seamless coverage of distance 0～40km.The dispersion being not added with having fixing dispersion measure in up-link is mended
Repaying device, the eye pattern under transmission 20km situation is shown in Figure 6.The embodiment of the present invention exists
Receiving terminal only by four level conversion be two level just can complete demodulation, it is not necessary to add it
The DSP algorithm such as his dispersion compensation, greatly reduce the complexity of demodulation.
The periodicity optical filter of OLT for simultaneously carry out downstream signal frequency equilibrium and
Chirp management.Through the feasibility of the experimental verification program, the spectrum of its periodicity optical filter
Type figure is shown in Figure 2, periodically optical filter free transmission range, primary signal and filtered
Device filtered flashlight spectrogram is shown in Figure 7, and in downlink, signal after filtering exists
Back-to-back the eye pattern under situation is shown in Figure 8, and in downlink, signal after filtering is passing
Eye pattern after defeated 40km optical fiber is shown in Figure 9, and signal the most filtered in downlink exists
Eye pattern after transmission 40km optical fiber is shown in Figure 10, it is seen that periodically optical filter one
Device can realize frequency equilibrium and dispersion management simultaneously, it is achieved 0～40km seamless high-quality
The transmission of amount, low cost signal.Simultaneously because the periodic filtering characteristic of wave filter, can be simultaneously
Realize the management to multiple wavelength.
In ONU, a width of 10GHz of band of downlink data receiver module；Upstream data is launched
Module has at least 10Gb/s data modulation could power, has tunable wave length function simultaneously, in order to
Realize the decolorizable of ONU, according to actual needs, the data of different ONU are modulated institute
On the wavelength needed.
The present embodiment utilizes the 10GHz optical device of low cost, it is achieved that up-downgoing speed is symmetrical
4 × 25G-PON, the program has the advantage that
(1) utilization has the dispersion compensation device of fixing dispersion measure, it is achieved the many ripples of upward signal
Long dispersion compensation, it is achieved that the full optical processing of dispersion compensation, greatly reduces system complex
Degree, improves the ageing of system.
(2) a periodically optical filter is utilized, it is achieved downstream signal multi-wavelength frequency equilibrium
And dispersion management, it is achieved that all-optical signal processing, it is to avoid High-speed Electric dispersion compensation module and
The use of electricity frequency equalizing algorithm.
(3) periodically device is easily integrated realization, can be integrated into other device of OLT
Together, reduce the size of device to a great extent, reduce system cost.
(4) this 4 × 25G-PON system does not change the existing PON system laid
The structure of optical fiber distributed type network, but also the light far-end in existing PON system can be continued to use
Node structure, thus smooth upgrade can be carried out in existing PON system, and completely with existing
PON system is compatible, and then can reduce the upgrade cost of PON system to a certain extent.
Those skilled in the art can carry out various modifications and variations to the embodiment of the present invention, if
If these amendment and modification within the scope of the claims in the present invention and equivalent technologies thereof, then this
A little amendments and modification are also within protection scope of the present invention.
The prior art that the content not described in detail in description is known to the skilled person.
Claims (16)
1. a symmetrical TWDM-PON system for high-speed transfer is realized with low speed optical device,
Including optical line terminal OLT, branched system optical fiber, light distant-end node, some distribution type fiber-optics
With some optical network unit ONU, light distant-end node is between OLT and ONU, and light is remote
One end of end node connects OLT by branched system optical fiber, and the other end passes through some distributed light
The some ONU of fine connection, distribution type fiber-optic and ONU one_to_one corresponding, it is characterised in that: institute
State OLT and include the first media control module, downlink data transmitter module, the first light wave
Division multiplexer and upstream data receiver module, the up, descending of OLT shares the first smooth wavelength-division
Multiplexer, the first media control module；Down direction, the first media controls mould
Block, downlink data transmitter module, the first light wavelength division multiplexing are sequentially connected with；Up direction, the
One light wavelength division multiplexing, upstream data receiver module, the first media control module sequentially connect
Connect；
Downlink data transmitter module includes multiple directly modulated lasers, second OWDM
Device, a periodicity optical filter and first image intensifer, all directly modulated lasers
One end is connected with the first media control module, the other end and the second light wavelength division multiplexing phase
Even, the second light wavelength division multiplexing, periodically optical filter, the first image intensifer, the first light
Wavelength division multiplexer is sequentially connected；
Upstream data receiver module include second image intensifer, one there is fixing dispersion
Dispersion compensation device, a light Wave decomposing multiplexer and multiple row photodetectors of amount,
The quantity of row photodetectors is identical with the quantity of directly modulated lasers, the first OWDM
Device, the second image intensifer, to have the dispersion compensation device of fixing dispersion measure, light Wave Decomposition multiple
It is sequentially connected with device, one end of all row photodetectors and light Wave decomposing multiplexer phase
Even, the other end and the first media control module are connected；
Each ONU includes the 3rd light wavelength division multiplexing, downlink data receiver module, the second matchmaker
Body medium control module and upstream data transmitter module, the up, descending of ONU shares the
Three light wavelength division multiplexings, the second media control module, down direction, the 3rd smooth wavelength-division is multiple
It is sequentially connected with by device, downlink data receiver module, the second media control module；Up side
To, the second media control module, upstream data transmitter module, the 3rd light wavelength division multiplexing
It is sequentially connected with.
2. the symmetry realizing high-speed transfer with low speed optical device as claimed in claim 1
TWDM-PON system, it is characterised in that: described upstream data transmitter module includes low speed electricity
Absorption modulation laser instrument EML, this low speed EML have tunable wave length characteristic, for the
The upward signal that two media control modules are sent carries out four level pulse amplitude modulation(PAM)s.
3. the symmetry realizing high-speed transfer with low speed optical device as claimed in claim 2
TWDM-PON system, it is characterised in that: described downlink data receiver module includes tunable optical
Wave filter, row photodetectors, the 3rd light wavelength division multiplexing, tunable optical filter, under
Row photodetector, the second media control module are sequentially connected.
4. the symmetry realizing high-speed transfer with low speed optical device as claimed in claim 3
TWDM-PON system, it is characterised in that: the first media in down direction, OLT are situated between
Matter control module controls the generation of downstream signal and process, downstream signal is modulated all directly
On the light carrier that adjusting laser produces；Each directly modulated lasers produces light carrier, simultaneously will be corresponding
The signal of telecommunication modulate on this light carrier, formed downstream signal send；Second OWDM
The downstream signal that all directly modulated lasers are sent by device carries out multiplexing process, under after multiplexing
Row signal issues periodically optical filter；Periodically optical filter is to the downstream signal after multiplexing
It is filtered, it is achieved the frequency equilibrium of downstream signal and chirp management, by filtered descending
Signal is sent to the first image intensifer；Filtered downstream signal is carried out by the first image intensifer
Amplifying, the downstream signal after amplifying is sent to the first light wavelength division multiplexing；First smooth wavelength-division
The downstream signal that first image intensifer is amplified by multiplexer is remote to light by branched system fiber-optic transfer
End node, downstream signal is transferred to each ONU by distribution type fiber-optic by light distant-end node；
Downstream signal is transferred to downlink data and receives by the 3rd light wavelength division multiplexing in each ONU
Module；Downstream signal is filtered by the tunable optical filter in downlink data receiver module,
Obtain the optical signal of Single wavelength；The optical signal of Single wavelength is changed into electricity by row photodetectors
Signal, is transferred to the second media control module, the second media control module docking
The signal of telecommunication received is transferred to customer side after processing；Second media control module also root
According to control protocol, control the reception of downstream signal, the center of major control tunable optical filter
Wavelength and the time slot of downstream signal reception.
5. the symmetry realizing high-speed transfer with low speed optical device as claimed in claim 3
TWDM-PON system, it is characterised in that: the second matchmaker in up direction, each ONU
Body medium control module is sent out according to control protocol, the control generation of upward signal, upstream data
That penetrates module launches wavelength and the time slot of transmission, by the uplink signal transmissions of generation to upper line number
According to the low speed EML in transmitter module, low speed EML, the second media control module is sent
Upward signal carry out four level pulse amplitude modulation(PAM)s, by through four level pulse amplitude modulation(PAM)s
Uplink signal transmissions is to the 3rd light wavelength division multiplexing；3rd light wavelength division multiplexing passes through distributed light
Fine by the uplink signal transmissions through four level pulse amplitude modulation(PAM)s to light distant-end node, difference
The wavelength of the upward signal in ONU is tuned as required, and operation wavelength is identical or not
With；The upward signal of the different wave length that each ONU transmits is coupled by light distant-end node, then
By branched system optical fiber by the uplink signal transmissions after coupling to OLT；
The first light wavelength division multiplexing in OLT by uplink signal transmissions to the second image intensifer；
Second image intensifer amplifies upward signal；There is the dispersion compensation device of fixing dispersion measure to upper
Row signal carries out dispersion compensation, and the dispersion measure that all up channels are corresponding keeps consistent；Light wavelength-division
Upward signal is demultiplexed by demultiplexer, by the uplink signal transmissions of different wave length to phase
The row photodetectors answered；Uplink optical signal is changed into telecommunications by row photodetectors
Number, then this signal of telecommunication is transferred to the first media control module；First media control
Molding block receives the signal of telecommunication that row photodetectors is sent, and carries out the signal of telecommunication received
Four level are to the conversion process of two level.
6. the symmetry realizing high-speed transfer with low speed optical device as claimed in claim 3
TWDM-PON system, it is characterised in that: downlink datas different in described OLT is launched
Module has different transmitting wavelength, between the different wavelength between downlink data transmitter module
Every the standard meeting ITU-T；Wavelength interval between down channel is periodicity optical filter
The integral multiple of free spectrum intervals, i.e. downstream signal spectrum is positioned at periodically optical filter spectrum
At the same position of type: rising edge or trailing edge；The periodically free frequency spectrum of optical filter
Interval is tunable.
7. the symmetry realizing high-speed transfer with low speed optical device as claimed in claim 3
TWDM-PON system, it is characterised in that: all row photodetectors, descending smooth electrical resistivity survey
Survey device and be low speed normal light electric explorer.
8. passing at a high speed with the realization of low speed optical device as according to any one of claim 1 to 7
Defeated symmetrical TWDM-PON system, it is characterised in that: described smooth distant-end node is by light splitting
Than the light branch/combiner composition for 1:N, N takes 64,128 or 256.
9. passing at a high speed with the realization of low speed optical device as according to any one of claim 1 to 7
Defeated symmetrical TWDM-PON system, it is characterised in that: described directly modulated lasers has ripple
Long tunable characteristic, its tunable wave length characteristic is controlled by temperature or electric current.
10. passing at a high speed with the realization of low speed optical device as according to any one of claim 1 to 7
Defeated symmetrical TWDM-PON system, it is characterised in that there is described in: fixing dispersion measure
Dispersion compensation device includes chirp grating, Fiber Bragg Grating FBG, dispersion compensating fiber.
11. passing at a high speed with the realization of low speed optical device as according to any one of claim 1 to 7
Defeated symmetrical TWDM-PON system, it is characterised in that: described downlink data transmitter module
In a width of 10GHz of band of directly modulated lasers.
12. symmetries realizing high-speed transfer with low speed optical device as claimed in claim 11
TWDM-PON system, it is characterised in that: the up light in described upstream data receiver module
Electric explorer uses photodiode PIN type light electric explorer, carries a width of 10GHz, and
By simple decision circuit, four level signals are changed into two level signals, it is achieved upstream data
Real-time process.
13. symmetries realizing high-speed transfer with low speed optical device as claimed in claim 11
TWDM-PON system, it is characterised in that: the band of described downlink data receiver module is a width of
10GHz。
14. symmetries realizing high-speed transfer with low speed optical device as claimed in claim 11
TWDM-PON system, it is characterised in that: described upstream data transmitter module has at least
10Gb/s data modulation could power, has tunable wave length function simultaneously, in order to realize ONU's
Decolorizable, according to actual needs, the data of different ONU are modulated required wavelength
On.
15. symmetries realizing high-speed transfer with low speed optical device as claimed in claim 11
TWDM-PON system, it is characterised in that: described OLT has the color of fixing dispersion measure
Dispersion compensator part is used for: compensate up 25Gbps tetra-level pulse am signals, its group
Time delay is periodically variable with wavelength change；The dispersion measure of this dispersion compensation device is
-650ps/nm。
16. symmetries realizing high-speed transfer with low speed optical device as claimed in claim 15
TWDM-PON system, it is characterised in that: this system realizes signal transmission distance 0～40km
Seamless coverage.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2018014565A1 (en) * | 2016-07-20 | 2018-01-25 | 上海诺基亚贝尔股份有限公司 | Method and device for sending and receiving data |
| CN112368587A (en) * | 2018-12-06 | 2021-02-12 | Ansys Lumerical知识产权有限责任公司 | System and method for creating a single-port interface for simulating bi-directional signals in a circuit using available circuit simulation standards |
| CN116015464A (en) * | 2022-12-28 | 2023-04-25 | 深圳市光为光通信科技有限公司 | High-speed photoelectric conversion module based on 5G communication and preparation process thereof |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103313150A (en) * | 2013-05-17 | 2013-09-18 | 上海交通大学 | Time-and wavelength-division multiplexed passive optical network transmission system based on directly modulated laser |
| CN105007546A (en) * | 2015-06-30 | 2015-10-28 | 上海交通大学 | TWDM-PON (Time Wavelength Division Multiplexing-Passive Optical Network) system and method based on wavelength-fixed and wavelength-adjustable lasers |
-
2016
- 2016-01-29 CN CN201610066452.9A patent/CN105743601A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103313150A (en) * | 2013-05-17 | 2013-09-18 | 上海交通大学 | Time-and wavelength-division multiplexed passive optical network transmission system based on directly modulated laser |
| CN105007546A (en) * | 2015-06-30 | 2015-10-28 | 上海交通大学 | TWDM-PON (Time Wavelength Division Multiplexing-Passive Optical Network) system and method based on wavelength-fixed and wavelength-adjustable lasers |
Non-Patent Citations (1)
| Title |
|---|
| HONGGUANG ZHANG等: "30km Downstream Transmission Using 4×25Gb/s 4-PAM Modulation with Commercial 10Gps TOSA and ROSA for 100Gb/s-PON", 《OPTICAL FIBER COMMUNICATION CONFERENCE》 * |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2018014565A1 (en) * | 2016-07-20 | 2018-01-25 | 上海诺基亚贝尔股份有限公司 | Method and device for sending and receiving data |
| US11128377B2 (en) | 2016-07-20 | 2021-09-21 | Alcatel Lucent | Method and device of transmitting and receiving data |
| CN112368587A (en) * | 2018-12-06 | 2021-02-12 | Ansys Lumerical知识产权有限责任公司 | System and method for creating a single-port interface for simulating bi-directional signals in a circuit using available circuit simulation standards |
| CN112368587B (en) * | 2018-12-06 | 2023-10-24 | Ansys 公司 | System and method for creating a single port interface for simulating a bi-directional signal in a circuit using available circuit simulation standards |
| CN116015464A (en) * | 2022-12-28 | 2023-04-25 | 深圳市光为光通信科技有限公司 | High-speed photoelectric conversion module based on 5G communication and preparation process thereof |
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