CN110324089A

CN110324089A - A kind of method for transmitting signals and relevant device of passive optical network

Info

Publication number: CN110324089A
Application number: CN201810296529.0A
Authority: CN
Inventors: 姚殊畅; 方李明; 叶志成
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2018-03-30
Filing date: 2018-03-30
Publication date: 2019-10-11
Anticipated expiration: 2038-03-30
Also published as: WO2019184819A1; CN110324089B

Abstract

The embodiment of the present application discloses a kind of method for transmitting signals of passive optical network, for solving the problems, such as wavelength management difficulty, and reduces device cost.The described method includes: optical line terminal OLT generates the corresponding downlink frequency division multiplexed electrical signal of multiple downlink sub-bands, each downlink sub-band is not overlapped on frequency domain in the multiple downlink sub-band, and each downlink sub-band is corresponding with one group of optical network unit ONU；The downlink frequency division multiplexed electrical signal is loaded on OLT transmitting light and obtains downlink frequency division multiplexing optical signal by the OLT；The OLT sends the downlink frequency division multiplexing optical signal, so that the ONU that the frequency of the intrinsic light of ONU is first frequency obtains the corresponding downlink sub-band signal of the ONU from the downlink frequency division multiplexing optical signal, the first frequency is corresponding with one of downlink sub-band in the multiple downlink sub-band.

Description

A kind of method for transmitting signals and relevant device of passive optical network

Technical field

This application involves field of communication technology more particularly to the method for transmitting signals and correlation of a kind of passive optical network Equipment.

Background technique

Passive optical network (passive optical network, PON) system, is the last of optical fiber transmission network One kilometer of solution can save a large amount of fiber resources, the light net suitable for magnanimity end branch by sharing trunk optical fiber Network system.In recent years, with the rising of people's bandwidth demand, PON system is constantly being updated the replacement.Currently, Gbit PON System is largely disposed, and the deployment of 10Gbit PON system starts upper amount, with 4k TV (television, TV), virtual reality The development of (virtual reality, VR) contour band width service, next-generation 100Gbit capacity PON system have also been included in electrically With Electronic Engineering Association (institute of electrical and electronics engineers, IEEE) and state The discussion row of the big normal structure of border telecommunication union (International Telecommunication Union, ITU) ITU two Column.

Before NGPON2 standard, the dilatation of PON system capacity is all realized by way of promoting Single wavelength signal rate, And optical line terminal (optical is realized using the mode of time division multiplexing (time division multiplexing, TDM) Line terminal, OLT) with Customer Premises Network unit (optical network unit, ONU) between interconnection.Therefore, The promotion of PON system rate each time, all bandwidth to system power budget, photoelectric device and cost propose very high want It asks.

In the prior art, PON system generally use wavelength-division multiplex (wavelength division multiplexing, WDM) mode realizes the intercommunication between OLT and ONU in the form of end-to-end (peer to peer), as shown in Figure 1, the side OLT is set Multiple lasers are set, carry out signal modulation for each laser, so that each laser issues the light carrier letter of different wave length Number, it sends end side and merges together these optical carriers through wavelength division multiplexer, and be coupled to same root optical fiber in optical link It is transmitted；The optical carrier of each wavelength is separated through shunt module (demultiplexer) in receiving end, then by ONU Receiver receives and parsing.

In this mode, OLT needs the carrier signal for each ONU modulation different wave length, then for ONU Numerous PON system, it is necessary to numerous lasers is set, the carrier signal of a large amount of different wave length, at high cost, wavelength tube are modulated Reason is difficult.

Summary of the invention

The embodiment of the present application provides the method for transmitting signals and relevant device of a kind of PON system, for reducing equipment at This.

In view of this, the application first aspect provides a kind of method for transmitting signals of PON system, this method comprises: light Line terminal generates the corresponding downlink frequency division multiplexed electrical signal of multiple downlink sub-bands, and the electric signal is then loaded into optical link The frequency-division multiplex singal in area of light, i.e. downlink frequency division multiplexing optical signal are obtained on terminal transmission light, finally answer the downlink frequency division Launched with optical signal, allows the optical network unit that the intrinsic light frequency of optical network unit is first frequency from the downlink frequency Divide in multiplexing optical signal and obtains the corresponding downlink sub-band signal of the optical network unit.

It should be noted that in this implementation in multiple downlink sub-bands corresponding with downlink frequency division multiplexed electrical signal, Each downlink sub-band is not overlapped on frequency domain, and the corresponding one group of ONU of each downlink sub-band.And it can be multiple from downlink frequency division With the optical network unit for obtaining corresponding downlink sub-band signal in optical signal, intrinsic light frequency need and one of them under Row sub-band is corresponding, i.e., one of downlink sub-band in first frequency and the multiple downlink sub-band is corresponding.

In this implementation, downlink frequency division multiplexed electrical signal is according on frequency domain on nonoverlapping multiple downlink sub-bands Downlink signal generate, each downlink sub-band corresponding one group of ONU, i.e., shared by the downlink signal that different groups of ONU is received Frequency band is not overlapped, and there is no interference, so that ONU can accurately receive itself corresponding downlink signal, improves user side Communication quality.Frequency-division multiplex singal is modulated in electrical domain in addition, being originally achieved in that, which is loaded into transmitting ONU is passed in light, therefore, OLT only needs a laser that can modulate the corresponding sub-band signal of different ONU, no It needs to be arranged multiple lasers, does not also need the optical signal for issuing multiple and different wavelength, both solved asking for wavelength management difficulty Topic, and reduce device cost.

In conjunction with the application in a first aspect, in the first implementation of the application first aspect, optical line terminal can be with Generate the corresponding downlink frequency division multiplexed electrical signal of multiple sub-bands in the following way: optical line terminal first generates each optical-fiber network The corresponding baseband signal of unit carries out shaping to these baseband signals respectively by low-pass filter and obtains each optical line terminal Then corresponding target baseband signal is directed to each optical network unit, by the corresponding target baseband signal of the optical network unit again It carries out frequency displacement and obtains the corresponding downlink sub-band signal of the optical network unit, finally again by the corresponding downlink of each optical network unit Sub-band signal merges to obtain downlink frequency division multiplexed electrical signal.

In this implementation, optical line terminal carries out shaping to baseband signal by low-pass filter, and having filtered out need not The band signal wanted, so as to realize that multiple word frequency bands corresponding with downlink frequency division multiplexed electrical signal are not overlapped on frequency domain, Avoid the interference between the corresponding downlink sub-band signal of each ONU.

In conjunction with the first implementation of the application first aspect or first aspect, at second of the application first aspect In implementation, optical line terminal can be light net before generating the corresponding downlink frequency division multiplexed electrical signal of multiple downlink sub-bands Network unit allocation of downlink sub-band, specifically can be in the following way: optical line terminal determines the corresponding downlink frequency of PON system It is in idle condition or unregistered full target sub-band in band, inquiry message is then sent on target sub-band, and suspend Signal is sent on other sub-bands other than target sub-band, so that optical network unit can be according to target sub-band On inquiry message determine first frequency, and this target sub-band is exactly that optical line terminal is distributed under the optical network unit Row sub-band, i.e. the downlink sub-band of optical network unit and target sub-band are corresponding.

It is optical network unit allocation of downlink sub-band that this implementation, which provides a kind of, and optical network unit is made to determine intrinsic light Frequency concrete mode, improve the realizability of scheme.

In conjunction with the application in a first aspect, any one realization side in the first to second implementation of first aspect Formula, in the third implementation of the application first aspect, optical line terminal is in the case where the multiple downlink sub-bands of generation are corresponding Line frequency divides before multiplexed electrical signal, can first determine the uplink sub-band for PON system uplink, and be used for PON system The uplink sub-band of downlink transfer, i.e. division uplink and downlink sub-band, can specifically divide in the following way: optical line terminal will First sub-band as uplink subband allocation to the optical network unit in PON system, and using the second sub-band as downlink son Bandwidth assignment is to the optical network unit in PON system, wherein the first sub-band and the second sub-band are adjacent on frequency domain, also It is two sub-bands said for arbitrary neighborhood on frequency domain, optical line terminal can be used as uplink sub-band for one of, will be another One is used as uplink sub-band.

Sub-band is staggered distribution by this implementation, it is possible to prevente effectively from the reflection signal of different sub-bands is to uplink and downlink light The sub-band information of signal brings interference.

In conjunction with the application in a first aspect, the first of first aspect any one realization side into the third implementation Formula, in the 4th kind of implementation of the application first aspect, following operation: optical line terminal is can also be performed in optical line terminal The corresponding each uplink sub-band telecommunications of uplink FDM optical signal is obtained by the intrinsic light of the optical line terminal of second frequency Number, wherein second frequency is corresponding with the centre frequency of uplink FDM optical signal, and uplink FDM optical signal is on multiple The signal obtained after row sub-band optical signal multiplex.

In this implementation, optical line terminal can receive the uplink of optical network unit transmission by way of relevant detection Signal, i.e. optical line terminal are only needed the centre frequency of intrinsic optical registration uplink FDM optical signal, it will be able to be obtained each The uplink signal that a optical network unit is sent, it is easy to operate, it is at low cost.

In conjunction with the 4th kind of implementation of the application first aspect, in the 5th kind of implementation of the application first aspect In, optical line terminal emits light and the intrinsic light of optical line terminal is the light that same light source issues.

In this implementation, the Receiver And Transmitter of optical line terminal shares a light source, effectively reduce equipment at This, and ensure that effective alignment of intrinsic light frequency.

The application second aspect provides the method for transmitting signals of another PON system, this method comprises: optical network unit It is first frequency by the set of frequency of the intrinsic light of optical network unit, first frequency is corresponding with target sub-band, passes through first frequency The intrinsic light of optical network unit, optical network unit obtains optical network unit corresponding downlink from downlink frequency division multiplexing optical signal Band signal, downlink frequency division multiplexing optical signal are optical line terminal by the corresponding downlink frequency division multiplex telecommunication of multiple downlink sub-bands It number is loaded into and to be obtained on the intrinsic light of optical line terminal, it is in multiple downlink sub-bands corresponding with downlink frequency division multiplexed electrical signal every A sub-band is not overlapped on frequency domain, and target sub-band is one of downlink son frequency in this multiple downlink sub-band Band.

In conjunction with the application second aspect, in the first implementation of the application second aspect, optical network unit is by light Before the set of frequency of the intrinsic light of network unit is first frequency, optical network unit can be determined as follows the first frequency Rate: optical network unit adjusts the frequency of the intrinsic light of optical network unit, and is directed to the intrinsic light of optical network unit of each frequency, to this The intrinsic light of optical network unit and optical line terminal carry out relevant detection in the inquiry message that target sub-band is sent, and determine each frequency Then the corresponding frequency of maximum value in relevant detection output power is determined as the first frequency by the corresponding relevant detection output power of rate Rate.

This implementation provides a kind of concrete mode of frequency that intrinsic light is determined for optical network unit, improves scheme Realizability.

In conjunction with the first implementation of the application second aspect or second aspect, at second of the application second aspect In implementation, following operation can also be performed in optical network unit: optical network unit carries out frequency displacement to baseband signal and obtains light net Then uplink sub-band electric signal is loaded on optical network unit transmitting light and obtains by the corresponding uplink sub-band electric signal of network unit To uplink sub-band optical signal, the uplink sub-band optical signal is retransmited, so that the passive wave multiplexer in PON system can be with The uplink sub-band optical signal that other optical network units in the uplink sub-band optical signal and PON system are sent is carried out multiplex to obtain To uplink FDM optical signal, then optical line terminal passes through available uplink of the intrinsic light of optical line terminal of second frequency The corresponding each uplink sub-band electric signal of frequency division multiplexing optical signal.

It should be understood that the corresponding uplink sub-band electric signal of optical network unit and optical line terminal distribute in this implementation Corresponding to the uplink sub-band of the optical network unit, second frequency is corresponding with the centre frequency of uplink FDM optical signal.

In this implementation, the centre frequency of uplink FDM optical signal is equal to the frequency of the laser of optical network unit In addition the centre frequency of electrical domain radiofrequency signal, this implementation can carry out radio-frequency modulations in electrical domain, not to laser frequency Stabilization compensates, so that optical network unit issues stable optical signal, so as to avoid different optical network units from sending Crosstalk between uplink signal.

In conjunction with second of implementation of the application second aspect, in the third implementation of the application second aspect In, optical network unit specifically can in the following way electrical domain carry out radio-frequency modulations to compensate the unstable of laser, i.e., on The uplink sub-band that the centre frequency and optical line terminal for stating uplink sub-band electric signal distribute to optical network unit is corresponding specific It refers to: the centre frequency f of uplink sub-band electric signal₂=f-f₁Δ f, wherein f is that optical line terminal distributes to optical-fiber network list The centre frequency of the uplink sub-band of member, f₁Emit the frequency of light for optical network unit, Δ f is according to downlink sub-band electric signal The frequency deviation value being calculated by frequency excursion algorithm.

This implementation provides the concrete mode that a kind of pair of laser frequency compensates, and improves can be achieved for scheme Property.

In conjunction with the application second aspect, first any one realization side into the third implementation of second aspect Formula, in the 4th kind of implementation of the application second aspect, optical network unit emits light and the intrinsic light of optical network unit is light The light that same unit issues in network unit.

In this implementation, the Receiver And Transmitter of optical network unit shares a light source, effectively reduce equipment at This, and ensure that effective alignment of intrinsic light frequency, avoid the crosstalk between frequency band.

The application third aspect additionally provides a kind of method for transmitting signals of PON system, this method comprises: optical line terminal The corresponding each uplink sub-band telecommunications of uplink FDM optical signal is obtained by the intrinsic light of the optical line terminal of second frequency Number.

It should be understood that second frequency is corresponding with the centre frequency of uplink FDM optical signal, upper line frequency in this implementation Point multiplexing optical signal is the signal obtained after multiple uplink sub-band optical signal multiplex.

In this implementation, optical line terminal is only needed the center frequency of intrinsic optical registration uplink FDM optical signal Rate, it will be able to the uplink signal that each optical network unit is sent is obtained, it is easy to operate, it is at low cost.

In conjunction with the application third aspect, in the first implementation of the application third aspect, optical line terminal is being obtained Before taking the corresponding each uplink sub-band electric signal of uplink FDM optical signal, it can first determine and be used for PON system uplink The uplink sub-band of transmission, and for the uplink sub-band of PON system downlink transfer, i.e. division uplink and downlink sub-band, specifically may be used To divide in the following way: optical line terminal is by the first sub-band as uplink subband allocation to the light net in PON system Network unit, and using the second sub-band as downlink subband allocation to the optical network unit in PON system, wherein the first son frequency Band and the second sub-band are adjacent on frequency domain, that is to say, that for two sub-bands of arbitrary neighborhood on frequency domain, optical line terminal It can be used as uplink sub-band by one of, using another as uplink sub-band.

In conjunction with the first implementation of the application third aspect or the third aspect, at second of the application third aspect In implementation, optical line terminal can be in the following way the optical network unit allocation of downlink sub-band in PON system: light Line terminal determines to be in idle condition or unregistered full target in the corresponding downlink sub-band (i.e. first band) of PON system Then sub-band sends inquiry message on target sub-band, and pauses at other sub-bands other than target sub-band Upper transmission signal, so that optical network unit can determine first frequency according to the inquiry message on target sub-band, and this Target sub-band is exactly the downlink sub-band that optical line terminal distributes to the optical network unit, i.e. the downlink son frequency of optical network unit Band and target sub-band are corresponding.

The application fourth aspect provides a kind of method for transmitting signals of PON system, this method comprises: optical network unit pair Baseband signal carries out frequency displacement and obtains the corresponding uplink sub-band electric signal of optical network unit, then adds uplink sub-band electric signal It is downloaded on optical network unit transmitting light and obtains uplink sub-band optical signal, retransmit the uplink sub-band optical signal, so that What the passive wave multiplexer in PON system can send other optical network units in the uplink sub-band optical signal and PON system Uplink sub-band optical signal carries out multiplex and obtains uplink FDM optical signal, then the light that optical line terminal passes through second frequency The corresponding each uplink sub-band electric signal of the available uplink FDM optical signal of the intrinsic light of road terminal.

In conjunction with the application fourth aspect, in the first implementation of fourth aspect, optical network unit can specifically lead to It crosses and carries out radio-frequency modulations in electrical domain such as under type to compensate the unstable of laser, i.e., the center of above-mentioned uplink sub-band electric signal The uplink sub-band correspondence that frequency and optical line terminal distribute to optical network unit refers specifically to: uplink sub-band electric signal Centre frequency f₂=f-f₁Δ f, wherein f is the centre frequency for the uplink sub-band that optical line terminal distributes to optical network unit, f₁Emit the frequency of light for optical network unit, Δ f is to be calculated according to downlink sub-band electric signal by frequency excursion algorithm Frequency deviation value.

In conjunction with the first implementation of the application fourth aspect or fourth aspect, at second of the application fourth aspect In implementation, optical network unit is obtaining the corresponding uplink sub-band electric signal of optical network unit to baseband signal progress frequency displacement It before can first determine that optical line terminal distributes to the downlink sub-band and the intrinsic light of optical network unit of the optical network unit Frequency, specifically can be in the following way: optical network unit adjusts the frequency of the intrinsic light of optical network unit, and is directed to each frequency The intrinsic light of optical network unit, the inquiry message that the intrinsic light of the optical network unit and optical line terminal are sent in target sub-band Relevant detection is carried out, determines the corresponding relevant detection output power of each frequency, it then will be maximum in relevant detection output power It is worth corresponding frequency and is determined as first frequency.

The 5th aspect of the application provides a kind of optical line terminal, which includes:

Generation module, for generating the corresponding downlink frequency division multiplexed electrical signal of multiple downlink sub-bands, the multiple downlink Each downlink sub-band is not overlapped on frequency domain in sub-band, and each downlink sub-band is corresponding with one group of optical network unit ONU；

Loading module obtains downlink frequency division multiplexed optical for downlink frequency division multiplexed electrical signal to be loaded on OLT transmitting light Signal；

Sending module, for sending downlink frequency division multiplexing optical signal, so that the frequency of the intrinsic light of ONU is first frequency ONU obtains the corresponding downlink sub-band signal of ONU, first frequency and the multiple downlink from downlink frequency division multiplexing optical signal One of downlink sub-band in frequency band is corresponding.

In conjunction with the 5th aspect of the application, in the first implementation of the 5th aspect of the application, generation module includes:

Submodule is generated, for generating the corresponding baseband signal of each ONU；

Shaping submodule block obtains the corresponding target of each ONU for carrying out shaping to baseband signal by low-pass filter Baseband signal；

It is corresponding to be obtained the ONU for being directed to each ONU by frequency displacement submodule for the corresponding target baseband signal frequency displacement of the ONU Downlink sub-band on obtain the corresponding downlink sub-band signal of the ONU；

Merge submodule, for merging the corresponding downlink sub-band signal of each ONU to obtain downlink frequency division multiplex telecommunication Number.

In conjunction with the first implementation of the 5th aspect of the application or the 5th aspect, at second of the 5th aspect of the application In implementation, optical line terminal further include:

Determining module is in idle condition or unregistered full mesh for determining in the corresponding downlink sub-band of PON system Mark sub-band, wherein the corresponding downlink sub-band of PON system is not overlapped on frequency domain；

Sending module is also used to send inquiry message on target sub-band, and pauses at other than target sub-band Other frequency bands on send signal so that ONU determines first frequency according to inquiry message, target sub-band is corresponding with ONU Downlink sub-band.

Any one realization side in terms of the application the 5th, in first and second kinds of implementations of the 5th aspect Formula, in the third implementation of the application third aspect, optical line terminal further include:

Distribution module, for using the first sub-band as uplink sub-band as the ONU distributed in PON system, and will Second sub-band is as downlink subband allocation to the ONU in PON system, the first sub-band phase on frequency domain with the second sub-band It is adjacent.

In conjunction with the 5th aspect of the application, first any one realization side into the third implementation of the 5th aspect Formula, in the 4th kind of implementation of the 5th aspect of the application, optical line terminal further include:

Module is obtained, it is corresponding each to obtain uplink FDM optical signal for the intrinsic light of OLT by second frequency Uplink sub-band electric signal, second frequency is corresponding with the centre frequency of uplink FDM optical signal, uplink FDM light letter Number for the signal that obtains after multiple uplink sub-band optical signal multiplex.

In conjunction with the 4th kind of implementation of the 5th aspect of the application, in the 5th kind of implementation of the 5th aspect of the application In, optical line terminal emits the light that the intrinsic light of light and optical line terminal issues for same light source.

The 6th aspect of the application provides a kind of optical network unit, which includes:

Setup module, for being first frequency, first frequency and target sub-band pair by the set of frequency of the intrinsic light of ONU It answers；

It is corresponding to obtain ONU for the intrinsic light of ONU by first frequency from downlink frequency division multiplexing optical signal for receiving module Downlink sub-band signal, downlink frequency division multiplexing optical signal is OLT by the corresponding downlink frequency division multiplexed electrical signal of multiple sub-bands It is loaded on OLT transmitting light and obtains, each downlink sub-band is not overlapped on frequency domain in the multiple downlink sub-band, described Multiple downlink sub-bands include target sub-band.

In conjunction with the 6th aspect of the application, in the first implementation of the 6th aspect of the application, optical network unit is also wrapped It includes:

Adjustment module for adjusting the frequency of the intrinsic light of ONU, and is directed to the intrinsic light of ONU of each frequency, to the ONU sheet It levies light and OLT and carries out relevant detection in the inquiry message that target sub-band is sent, determine that the corresponding relevant detection of each frequency is defeated Power out；

Determining module, for determining, the corresponding frequency of maximum value is first frequency in relevant detection output power.

In conjunction with the first implementation of the 6th aspect of the application or the 6th aspect, at second of the 6th aspect of the application In implementation, optical network unit further include:

Frequency displacement module obtains the corresponding uplink sub-band electric signal of ONU, uplink son frequency for carrying out frequency displacement to baseband signal It is corresponding that the centre frequency of charged signal with OLT distributes to the uplink sub-band of ONU；

Loading module obtains uplink sub-band optical signal for uplink sub-band electric signal to be loaded on ONU transmitting light；

Sending module, for sending the corresponding uplink sub-band optical signal of ONU, so that passive wave multiplexer is corresponding to ONU Sub-band optical signal and PON system in the uplink sub-band optical signal that sends of other ONU carry out multiplex to obtain uplink frequency division multiple With optical signal, OLT obtains the corresponding each uplink sub-band of uplink FDM optical signal by the intrinsic light of OLT of second frequency Electric signal, second frequency are corresponding with the centre frequency of uplink FDM optical signal.

In conjunction with second of implementation of the 6th aspect of the application, in the third implementation of the 6th aspect of the application In, it includes: uplink sub-band electricity that it is corresponding, which to distribute to the uplink sub-band of ONU, with OLT for the centre frequency of uplink sub-band electric signal The centre frequency f of signal₂=f-f₁Δ f, wherein f is the centre frequency for the uplink sub-band that OLT distributes to ONU, f₁For ONU Emit the frequency of light, Δ f is the frequency deviation value being calculated according to downlink sub-band electric signal by frequency excursion algorithm.

In conjunction with second or the third implementation of the 6th aspect of the application, in the 4th kind of realization of the 6th aspect of the application In mode, ONU emits light and the intrinsic light of ONU is the light that the same light source issues in ONU.

The 7th aspect of the application provides a kind of optical line terminal, which includes:

Module is obtained, it is corresponding to obtain uplink FDM optical signal for the intrinsic light of optical line terminal by second frequency Each uplink sub-band electric signal.

In conjunction with the 7th aspect of the application, in the first implementation of the 7th aspect of the application, optical line terminal is also wrapped It includes:

Distribution module, for using the first sub-band as uplink subband allocation to the optical network unit in PON system, and Using the second sub-band as downlink subband allocation to the optical network unit in PON system, wherein the first sub-band and the second son Frequency band is adjacent on frequency domain, that is to say, that for two sub-bands of arbitrary neighborhood on frequency domain, optical line terminal can will wherein one It is a to be used as uplink sub-band, using another as uplink sub-band.

In conjunction with the first implementation of the 7th aspect of the application or the 7th aspect, at second of the 7th aspect of the application In implementation, distribution module includes:

It determines submodule, is in idle condition for determining in the corresponding downlink sub-band (i.e. first band) of PON system Or unregistered full target sub-band；

Sending submodule for sending inquiry message on target sub-band, and pauses at other than target sub-band Other sub-bands on send signal so that optical network unit can determine first according to the inquiry message on target sub-band Frequency, and this target sub-band is exactly the downlink sub-band that optical line terminal distributes to the optical network unit, i.e. optical-fiber network list The downlink sub-band and target sub-band of member are corresponding.

The application eighth aspect provides a kind of optical network unit, which includes:

Frequency displacement module obtains the corresponding uplink sub-band electric signal of optical network unit for carrying out frequency displacement to baseband signal；

Loading module obtains uplink sub-band for uplink sub-band electric signal to be loaded on optical network unit transmitting light Optical signal；

Sending module, for sending the uplink sub-band optical signal, so that passive wave multiplexer in PON system can be with The uplink sub-band optical signal that other optical network units in the uplink sub-band optical signal and PON system are sent is carried out multiplex to obtain To uplink FDM optical signal, then optical line terminal passes through available uplink of the intrinsic light of optical line terminal of second frequency The corresponding each uplink sub-band electric signal of frequency division multiplexing optical signal.

In conjunction with the application eighth aspect, in the first implementation of eighth aspect, in uplink sub-band electric signal The uplink sub-band correspondence that frequency of heart and optical line terminal distribute to optical network unit refers specifically to: uplink sub-band electric signal Centre frequency f₂=f-f₁Δ f, wherein f is the center frequency for the uplink sub-band that optical line terminal distributes to optical network unit Rate, f₁Emit the frequency of light for optical network unit, Δ f is to calculate according to downlink sub-band electric signal by frequency excursion algorithm The frequency deviation value arrived.

In conjunction with the first implementation of the application eighth aspect or eighth aspect, at second of the application eighth aspect In implementation, optical network unit further include:

Adjustment module, for adjusting the frequency of the intrinsic light of optical network unit；

Determining module, for being directed to the intrinsic light of optical network unit of each frequency, to the intrinsic light of the optical network unit and light Line terminal carries out relevant detection in the inquiry message that target sub-band is sent, and determines the corresponding relevant detection output of each frequency Power, and the corresponding frequency of maximum value in relevant detection output power is determined as first frequency.

The 9th aspect of the application provides a kind of optical line terminal, which includes: processor, and memory swashs Light device；Wherein, laser is for issuing optical signal, and memory is for storing program, and processor is for executing program so that OLT It at least executes following steps: generating the corresponding downlink frequency division multiplexed electrical signal of multiple downlink sub-bands, then add the electric signal It is downloaded on optical line terminal transmitting light and obtains the frequency-division multiplex singal in area of light, i.e. downlink frequency division multiplexing optical signal, finally should Downlink frequency division multiplexing optical signal is launched, so that the optical network unit that the intrinsic light frequency of optical network unit is first frequency can be with The corresponding downlink sub-band signal of the optical network unit is obtained from the downlink frequency division multiplexing optical signal.

In conjunction with the 9th aspect of the application, in the first implementation of the 9th aspect of the application, multiple downlinks are being generated In the step of sub-band corresponding downlink frequency division multiplexed electrical signal, processor, which executes program, makes OLT at least execute following steps: raw At the corresponding baseband signal of each optical network unit, shaping is carried out to these baseband signals respectively by low-pass filter and is obtained respectively Then the corresponding target baseband signal of a optical line terminal is directed to each optical network unit again, the optical network unit is corresponding Target baseband signal carries out frequency displacement and obtains the corresponding downlink sub-band signal of the optical network unit, finally again by each optical-fiber network list The corresponding downlink sub-band signal of member merges to obtain downlink frequency division multiplexed electrical signal.

In conjunction with the first implementation of the 9th aspect of the application or the 9th aspect, at second of the 9th aspect of the application In implementation, processor, which executes program, also executes the following steps: OLT in the corresponding downlink sub-band of determining PON system In idle state or unregistered full target sub-band, then on target sub-band send inquiry message, and pause in addition to Signal is sent on other sub-bands other than target sub-band, so that optical network unit can be according to the inquiry on target sub-band Ask that message determines first frequency, and this target sub-band is exactly the downlink son frequency that optical line terminal distributes to the optical network unit Band, i.e. the downlink sub-band of optical network unit and target sub-band are corresponding.

Any one realization side in terms of the application the 9th, in the first to second implementation of the 9th aspect Formula, in the third implementation of the aspect of the application the 9th, processor, which executes program, also executes the following steps: OLT by the One sub-band as uplink subband allocation to the optical network unit in PON system, and using the second sub-band as downlink son frequency Band distributes to the optical network unit in PON system, wherein and the first sub-band and the second sub-band are adjacent on frequency domain, that is, Say that two sub-bands for arbitrary neighborhood on frequency domain, optical line terminal can be used as uplink sub-band for one of, it will be another It is a to be used as uplink sub-band.

In conjunction with the 9th aspect of the application, first any one realization side into the third implementation of the 9th aspect Formula, in the 4th kind of implementation of the aspect of the application the 9th, processor, which executes program and also executes the following steps: OLT, to be passed through The intrinsic light of the optical line terminal of second frequency obtains the corresponding each uplink sub-band electric signal of uplink FDM optical signal, In, second frequency is corresponding with the centre frequency of uplink FDM optical signal, and uplink FDM optical signal is multiple uplink The signal obtained after frequency band optical signal multiplex.

In conjunction with the 4th kind of implementation of the 9th aspect of the application, in the 5th kind of implementation of the 9th aspect of the application In, optical line terminal emits light and the intrinsic light of optical line terminal is the light that same light source issues.

The tenth aspect of the application provides a kind of optical network unit, which includes: processor, and memory swashs Light device；Wherein, laser is for issuing optical signal, and memory is for storing program, and processor is for executing program so that ONU It at least executes following steps: being first frequency, first frequency and target sub-band by the set of frequency of the intrinsic light of optical network unit It is corresponding, by the intrinsic light of the optical network unit of first frequency, it is corresponding that optical network unit is obtained from downlink frequency division multiplexing optical signal Downlink sub-band signal, downlink frequency division multiplexing optical signal is optical line terminal by the corresponding downlink frequency division of multiple downlink sub-bands Multiplexed electrical signal, which is loaded into, to be obtained on the intrinsic light of optical line terminal, multiple downlinks corresponding with downlink frequency division multiplexed electrical signal Each sub-band is not overlapped on frequency domain in frequency band, and target sub-band is under one of them in this multiple downlink sub-band Row sub-band.

In conjunction with the tenth aspect of the application, in the first implementation of the tenth aspect of the application, processor is for executing Program is so that ONU also executes the following steps: the frequency for adjusting the intrinsic light of optical network unit, and is directed to the optical-fiber network of each frequency The intrinsic light of unit is concerned with to the intrinsic light of the optical network unit and optical line terminal in the inquiry message that target sub-band is sent Detection, determines the corresponding relevant detection output power of each frequency, then that maximum value in relevant detection output power is corresponding Frequency is determined as first frequency.

In conjunction with the first implementation of the tenth aspect of the application or the tenth aspect, at second of the tenth aspect of the application In implementation, processor is for executing program so that ONU, which is also executed the following steps:, obtains light to baseband signal progress frequency displacement Then uplink sub-band electric signal is loaded on optical network unit transmitting light by the corresponding uplink sub-band electric signal of network unit Uplink sub-band optical signal is obtained, the uplink sub-band optical signal is retransmited, so that the passive wave multiplexer in PON system can Multiplex is carried out with the uplink sub-band optical signal for sending other optical network units in the uplink sub-band optical signal and PON system Uplink FDM optical signal is obtained, then optical line terminal is available on this by the intrinsic light of optical line terminal of second frequency Line frequency divides multiplexing optical signal corresponding each uplink sub-band electric signal.

In conjunction with second of implementation of the tenth aspect of the application, in the third implementation of the tenth aspect of the application In, the uplink sub-band that the centre frequency and optical line terminal of uplink sub-band electric signal distribute to optical network unit is corresponding specific It refers to: the centre frequency f of uplink sub-band electric signal₂=f-f₁Δ f, wherein f is that optical line terminal distributes to optical-fiber network list The centre frequency of the uplink sub-band of member, f₁Emit the frequency of light for optical network unit, Δ f is according to downlink sub-band electric signal The frequency deviation value being calculated by frequency excursion algorithm.

In conjunction with the tenth aspect of the application, first any one realization side into the third implementation of the tenth aspect Formula, in the 4th kind of implementation of the tenth aspect of the application, optical network unit emits light and the intrinsic light of optical network unit is light The light that same unit issues in network unit.

The tenth one side of the application provides a kind of optical line terminal, which includes: processor, memory, Laser；Wherein, laser is for issuing optical signal, memory for storing program, processor for executing program so that OLT at least executes following steps: it is corresponding to obtain uplink FDM optical signal by the intrinsic light of the optical line terminal of second frequency Each uplink sub-band electric signal

On the one hand in conjunction with the application the tenth, in the first implementation of the tenth one side of the application, processor is used for Program is executed so that OLT is also executed the following steps: using the first sub-band as uplink subband allocation to the light in PON system Network unit, and using the second sub-band as downlink subband allocation to the optical network unit in PON system, wherein the first son Frequency band and the second sub-band are adjacent on frequency domain, that is to say, that for two sub-bands of arbitrary neighborhood on frequency domain, optical link is whole End can be used as uplink sub-band for one of, using another as uplink sub-band.

In conjunction with the first implementation of the tenth one side of the application or the tenth one side, in the tenth one side of the application In second of implementation, processor for execute program so that OLT to also execute the following steps: determining PON system corresponding It is in idle condition in downlink sub-band (i.e. first band) or unregistered full target sub-band, then on target sub-band Inquiry message is sent, and pauses on other sub-bands other than target sub-band and sends signal, so that optical-fiber network list Member can determine first frequency according to the inquiry message on target sub-band, and this target sub-band is exactly optical line terminal point The downlink sub-band of the dispensing optical network unit, i.e. the downlink sub-band of optical network unit and target sub-band are corresponding.

The aspect of the application the 12nd provides a kind of optical network unit, which includes: processor, memory, Laser；Wherein, laser is for issuing optical signal, memory for storing program, processor for executing program so that ONU at least executes following steps: carrying out frequency displacement to baseband signal and obtains the corresponding uplink sub-band electric signal of optical network unit, so Uplink sub-band electric signal is loaded on optical network unit transmitting light afterwards and obtains uplink sub-band optical signal, retransmits the uplink Sub-band optical signal, so that passive wave multiplexer in PON system can will be in the uplink sub-band optical signal and PON system The uplink sub-band optical signal that other optical network units are sent carries out multiplex and obtains uplink FDM optical signal, then optical link is whole Corresponding each uplink of the available uplink FDM optical signal of the intrinsic light of optical line terminal that end passes through second frequency Frequency band electric signal.

In conjunction with the 12nd aspect of the application, in the first implementation of the 12nd aspect, uplink sub-band electric signal Centre frequency and optical line terminal distribute to the uplink sub-band correspondence of optical network unit and refer specifically to: uplink sub-band electricity The centre frequency f of signal₂=f-f₁Δ f, wherein f is that optical line terminal is distributed in the uplink sub-band of optical network unit Frequency of heart, f₁Emit the frequency of light for optical network unit, Δ f is to pass through frequency excursion algorithm meter according to downlink sub-band electric signal Obtained frequency deviation value.

In conjunction with the first implementation of the 12nd aspect of the application or the 12nd aspect, at the 12nd aspect of the application In second of implementation, processor for execute program so that ONU also execute the following steps: adjust optical network unit it is intrinsic The frequency of light, and it is directed to the intrinsic light of optical network unit of each frequency, exist to the intrinsic light of the optical network unit and optical line terminal The inquiry message that target sub-band is sent carries out relevant detection, determines the corresponding relevant detection output power of each frequency, then The corresponding frequency of maximum value in relevant detection output power is determined as first frequency.

The 13rd aspect of the application provides a kind of PON system, which includes any one in terms of the such as the above-mentioned 5th Optical network unit in terms of optical line terminal and the above-mentioned 6th in implementation in any one implementation.

The application fourteenth aspect provides a kind of PON system, which includes any one in terms of the such as the above-mentioned 7th Optical line terminal in implementation and the optical network unit in above-mentioned eighth aspect any one implementation.

The 15th aspect of the application provides a kind of computer storage medium, and described state in computer readable storage medium is deposited Instruction is contained, when run on a computer, so that computer executes described in above-mentioned any one implementation of first aspect Method, or execute method described in any one implementation of second aspect, or execute above-mentioned any one reality of the third aspect The method of existing mode, or execute method described in any one implementation of fourth aspect.

The 16th aspect of the application provides a kind of computer program product including instruction, when it runs on computers When, so that computer executes method described in any one implementation of above-mentioned first aspect, or to execute second aspect any one Method described in kind implementation, or the method for executing above-mentioned any one implementation of the third aspect, or execute fourth aspect Method described in any one implementation.

As can be seen from the above technical solutions, the embodiment of the present application has the advantage that

In the embodiment of the present application, the corresponding downlink frequency division multiplexed electrical signal of multiple downlink frequencies is can be generated in OLT, by downlink frequency Point multiplexed electrical signal is loaded on OLT transmitting light and obtains lower frequency division multiplexing optical signal, and sends the downlink frequency division multiplexing optical signal, And ONU can obtain ONU pairs using the intrinsic light of ONU of first frequency by coherent receiver from downlink frequency division multiplexing optical signal The downlink sub-band signal answered, wherein first frequency is corresponding with one of downlink sub-band in above-mentioned multiple downstream bands. In the embodiment of the present application, downlink frequency division multiplexed electrical signal is according to the downlink on frequency domain on nonoverlapping multiple downlink sub-bands What signal generated, each corresponding one group of ONU of downlink sub-band, i.e., the occupied frequency of the downlink signal that different groups of ONU is received Band is not overlapped, and there is no interference, so that ONU can accurately receive itself corresponding downlink signal, improves the communication of user side Quality.In addition, the embodiment of the present application is to modulate frequency-division multiplex singal in electrical domain, which is loaded into transmitting light ONU is passed to, therefore, OLT only needs a laser that can modulate the corresponding sub-band signal of different ONU, does not need Multiple lasers are set, the optical signal for issuing multiple and different wavelength is not needed yet, had not only solved the problems, such as wavelength management difficulty, but also Reduce device cost.

Detailed description of the invention

Technical solution in ord to more clearly illustrate embodiments of the present application, below will be to required use in embodiment description Attached drawing be briefly described, it should be apparent that, the drawings in the following description are only some examples of the present application.

Fig. 1 is the structural schematic diagram for the PON system transmitted in the prior art using wavelength division multiplexed mode；

Fig. 2 is the PON system configuration diagram in the embodiment of the present application；

Fig. 3 is one embodiment schematic diagram of the method for transmitting signals of PON system in the embodiment of the present application；

Fig. 4 A is a schematic diagram of the uplink and downlink frequency band that OLT is divided in the embodiment of the present application；

Fig. 4 B is another embodiment schematic diagram of the method for transmitting signals of PON system in the embodiment of the present application；

Fig. 4 C is the structural schematic diagram of OLT transmitter in the embodiment of the present application；

Fig. 4 D is the structural schematic diagram of coherent receiver in the embodiment of the present application；

Fig. 5 is another embodiment schematic diagram of the method for transmitting signals of PON system in the embodiment of the present application；

Fig. 6 A is the structural schematic diagram of ONU transmitter in the embodiment of the present application；

Fig. 6 B is uplink FDM optical signal corresponding frequency spectrum signal after moving to electrical domain base band in the embodiment of the present application Figure；

Fig. 6 C is that ONU obtains the corresponding each uplink sub-band telecommunications of uplink FDM optical signal in the embodiment of the present application Number schematic diagram；

Fig. 7 is one embodiment schematic diagram of OLT in the embodiment of the present application；

Fig. 8 is another embodiment schematic diagram of OLT in the embodiment of the present application；

Fig. 9 is one embodiment schematic diagram of ONU in the embodiment of the present application；

Figure 10 is one embodiment schematic diagram of ONU in the embodiment of the present application；

Figure 11 is one embodiment schematic diagram of OLT in the embodiment of the present application；

Figure 12 is one embodiment schematic diagram of PON system in the embodiment of the present application.

Specific embodiment

Below in conjunction with the attached drawing in the embodiment of the present application, technical solutions in the embodiments of the present application carries out clear, complete Site preparation description, it is clear that described embodiments are only a part of embodiments of the present application, instead of all the embodiments.

The description and claims of this application and term " first ", " second ", " third " " in above-mentioned attached drawing The (if present)s such as four " are to be used to distinguish similar objects, without being used to describe a particular order or precedence order.It should manage The data that solution uses in this way are interchangeable under appropriate circumstances, so that embodiments herein described herein for example can be to remove Sequence other than those of illustrating or describe herein is implemented.In addition, term " includes " and " having " and theirs is any Deformation, it is intended that cover it is non-exclusive include, for example, containing the process, method of a series of steps or units, system, production Product or equipment those of are not necessarily limited to be clearly listed step or unit, but may include be not clearly listed or for this A little process, methods, the other step or units of product or equipment inherently.

It should be understood that the technical solution of the embodiment of the present application is applied to the communication system comprising PON, and such as: the whole world is mobile logical (global system of mobile communication, the GSM) system, CDMA (code division of news Multiple access, CDMA) system, wideband code division multiple access (wideband code division multiple Access, WCDMA) it system, General Packet Radio Service (general packet radio service, GPRS), drills for a long time Into (long term evolution, LTE) system, LTE frequency division duplex (frequency division duplex, FDD) system System, LTE time division duplex (time division duplex, TDD), Universal Mobile Communication System (universal mobile Telecommunication system, UMTS), global interconnection inserting of microwave (worldwide interoperability For microwave access, WiMAX) communication system or the 5th third-generation mobile communication technology (5th-generation, 5G) etc., It should be noted that the embodiment of the present application does not limit specific communication system.

The embodiment of the present application in order to facilitate understanding below simply introduces PON system.

PON refers in Optical Distribution Network (optical distribution network, ODN) without containing any electronics device The fiber optic network of part and electronic power supply, ODN are all made of passive devices such as optical splitters (Splitter), do not need valuable Active electronic devices.One PON includes the OLT for being installed on console for centralized control, and a batch is matched is installed on user ONU.ODN between OLT and ONU) optical fiber and passive optical splitters or coupler are contained, as shown in Figure 2.

PON system structure mainly by the OLT of central office, the ODN comprising Passive Optical Components, user terminal optical network unit (optical network unit, ONU)/ONT Optical Network Terminal (optical network terminal, ONT) composition, area Not Wei ONT located immediately at user terminal, and there are also other networks, such as Ethernet between ONU and user) and Element management system (EMS) it forms, generallys use point-to-multipoint tree topology.The embodiment of the present application will be introduced by taking ONU as an example, Ying Li It solves, function performed by ONU can also be executed by ONT in the application.

The embodiment of the present application in order to facilitate understanding, below to this application involves background technique be introduced.

Frequency division multiplexing (frequency division multiplexing, FDM) is exactly that will be used for transmission total band of channel Width is divided into several sub-bands (or subchannel), each 1 road signal of subchannel transmission.Frequency division multiplexing requires sum frequency wide Degree is greater than the sum of each sub-channel frequencies, while in order to guarantee that the signal transmitted in each subchannel is not interfere with each other, should be in each son Isolation strip is set up between channel, ensures that each road signal does not interfere with each other (one of condition) in this way.The characteristics of frequency multiplexing technique It is that the signals of all subchannel transmissions works in a parallel fashion, can not considers propagation delay time when transmitting per signal all the way.

Relevant detection: it is multiplied using the carrier wave of modulated signal with the modulated signal received, is then obtained by low-pass filtering To the detection mode of modulated signal.

Coherent receiver: in one built in receiver and continuous light source similar in signal optical source wavelength, by itself and signal light It is mixed and is detected, intrinsic light should be known as with continuous light source similar in optical source wavelength, that is, is used for the continuous light source of coherent reception Referred to as intrinsic light.

First the method for transmitting signals of PON system in the embodiment of the present application is introduced below, referring to Fig. 3, the application One embodiment of the method for transmitting signals of middle PON system includes:

301, the set of frequency of the intrinsic light of ONU is first frequency by ONU.

The total bandwidth of PON system is divided into several sub-bands by OLT, and is divided the sub-band of uplink and downlink signals Match, i.e. OLT determines the uplink sub-band that PON system uplink is used in several sub-bands, and is used for PON system downlink The downlink sub-band of transmission.

Specifically, OLT determine each downlink sub-band for downlink transfer between there are band separations, i.e., each under Row sub-band is not overlapped on frequency domain.In the present embodiment, as a kind of optional mode, OLT can be pressed several sub-bands Sequence is numbered, and as shown in Figure 4 A, numbers the sub-band for odd number as downlink sub-band for all, is even by all numbers Several sub-bands numbers the sub-band for odd number as uplink sub-band, by all numbers as uplink sub-band, or using all For even number sub-band as uplink sub-band, that is to say, that several corresponding sub-bands of PON system are with uplink and downlink interval Mode (uplink, downlink, uplink, downlink ...) divide, i.e., for any two sub-band adjacent on frequency domain (first son frequency Band and the second sub-band), one of sub-band (the first sub-band) can be used as uplink subband allocation to PON system by OLT In ONU, by another sub-band (the second sub-band) as downlink subband allocation to the ONU in PON system.

OLT is determined the downlink sub-band of downlink signal is used for transmission in PON system after, OLT is by these downlink sub-bands point After ONU in dispensing PON system, ONU determine itself corresponding sub-band, set the intrinsic light of ONU in coherent receiver to First frequency, first frequency sub-band corresponding with the ONU are corresponding.It should be understood that the present embodiment in, first frequency with ONU pairs The sub-band answered is corresponding to refer to that first frequency is the frequency on the sub-band, and specifically, first frequency is equal to the sub-band Centre frequency, or difference between the centre frequency of sub-band is in error range.

As a kind of optional mode, OLT can be in the following way by these downlink subband allocations in PON system ONU, i.e. ONU can be determined as follows itself corresponding sub-band:

(1) OLT is determined in the corresponding downlink sub-band of PON system in idle or unregistered full target sub-band；

(2) OLT sends inquiry message on target sub-band, and pauses at other frequency bands other than target sub-band Upper transmission signal；

(3) ONU adjusts the frequency of the intrinsic light of ONU, and is directed to the intrinsic light of ONU of each frequency, sends out the intrinsic light and OLT The inquiry message sent carries out relevant detection, determines the corresponding relevant detection output power of each frequency；

ONU phase is controlled by adjusting semiconductor cooler (thermo electric cooler, TEC) to online ONU The frequency of dry receiver, occupying spectrum width according to sub-band is that step-length is carrying out full bandwidth poll, i.e. ONU is logical by step-length of preset value The frequency that TEC adjusts the intrinsic light of ONU is crossed, as soon as every setting frequency, calculates the intrinsic light that coherent receiver issues under the frequency With the relevant detection output power of inquiry message, finished until the intrinsic light of all frequencies all detects.

(4) ONU determines that the corresponding frequency of maximum value is first frequency in the corresponding relevant detection output power of each frequency.

It should be understood that the frequency and target sub-band for representing intrinsic light most connect when relevant detection output signal power highest Closely.Then ONU determines the corresponding frequency of maximum value in the corresponding relevant detection output power of each frequency after full bandwidth poll Rate is first frequency, and the sub-band where first frequency is the corresponding sub-band of ONU.

It is first frequency by the set of frequency of the intrinsic light of ONU, i.e., by TEC after ONU determines first frequency through the above way Temperature value of temperature when being set in relevant detection output power maximum.

As a kind of optional mode, ONU is by the set of frequency of intrinsic light for after first frequency, ONU is according to first frequency Intrinsic light-receiving to downlink signal (inquiry message) carry out offset estimation and obtain frequency deviation value, and uplink is modulated according to frequency deviation value Sub-band signal reports registration information to OLT by the uplink sub-band signal, and the registration information is for requesting the first frequency of registration Sub-band where rate, the registration information include the media access control (Media Access Control, MAC) of the ONU Location.Specifically, ONU can modulate uplink sub-band signal in the following way: ONU is by low-pass filter to registration information pair The baseband signal answered is handled, and then by treated, signal carries out the signal in frequency displacement to target frequency, by target frequency On signal loading to ONU transmitting light in, complete the transmission of registration information.Wherein, the value of target frequency subtracts equal to first frequency Remove frequency deviation value.

After OLT receives the registration information of ONU transmission, determine that the sub-band of OLT request registration is corresponding with target sub-band, The MAC Address for recording ONU sends authorization message to ONU on target sub-band according to the MAC Address, and restores other son frequencies The transmission of band signal.

After the authorization message that ONU is sent to ONU by the intrinsic light-receiving of ONU of first frequency, carry out message processing and It is synchronous, then confirmation message is sent to OLT.It optionally, may include uplink Dynamic Bandwidth Allocation in the authorization message that ONU is sent Message is used to indicate the uplink sub-band that the ONU is used for transmission uplink signal, then ONU can will carry the base band of confirmation message On signal frequency shift to indicated uplink sub-band, and the signal loading after frequency displacement is passed into ONU into ONU transmitting light.ONU The authorization message of transmission can not also include uplink Dynamic Bandwidth Allocation message, and ONU can be by inquiring message with above-mentioned transmission Similar mode sends confirmation message, and specific details are not described herein again.

It after OLT receives the confirmation message of ONU transmission, that is, completes to shake hands, that is, completes point of the downlink sub-band of the ONU Match, ONU success is online, and hereafter, OLT and ONU start normal communication, and it includes uplink that OLT can be sent on target sub-band The downlink data of Dynamic Bandwidth Allocation message, ONU according to upstream bandwidth assignment messages carry out uplink sub-band signal modulation and It sends.As shown in Figure 4 B, it is a flow chart that OLT is ONU allocation of downlink sub-band.

It should be noted that the ONU of the same downlink sub-band (the intrinsic light of ONU is identical) will be had registered in the present embodiment It is considered an ONU group, i.e. the corresponding one group of ONU of a downlink sub-band, the intrinsic light of the ONU of same group of ONU is identical, under corresponding Row sub-band is identical.And there is interval between each downlink sub-band that OLT is divided, therefore the corresponding downlink of ONU of different groups Sub-band is not overlapped between frequency domain.

302, OLT generates the corresponding downlink frequency division multiplexed electrical signal of multiple downlink sub-bands.

OLT is that each online ONU distributes uplink sub-band, after establishing the communication connection with ONU, when needs are to different groups ONU send downlink signal when, OLT determines corresponding with these ONU multiple downlink sub-bands, and it is sub to generate this multiple downlink The corresponding downlink frequency-division multiplex singal of frequency band.It should be understood that sub-band division principle described in being based on above-mentioned 301, under this is multiple Each sub-band is not overlapped on frequency domain in row sub-band.

Specifically, OLT can generate downlink sub-band electric signal in the following way: OLT generates the corresponding base of each ONU Then band signal carries out shaping to baseband signal by low-pass filter and obtains the corresponding target baseband signal of each ONU, then needle To each ONU, the corresponding target baseband signal frequency displacement of the ONU is obtained to obtain this ONU pairs on the corresponding downlink sub-band of the ONU The downlink sub-band signal answered finally merges the corresponding downlink sub-band signal of each ONU to obtain downlink frequency division multiplex telecommunication Number.

303, downlink frequency division multiplexed electrical signal is loaded on OLT transmitting light and obtains downlink frequency division multiplexing optical signal by OLT.

After OLT generates the corresponding downlink frequency division multiplexed electrical signal of multiple downlink sub-bands, by downlink frequency division multiplexed electrical signal It is loaded on optical signal by optical modulator and obtains downlink frequency division multiplexing optical signal.

Specifically, in the present embodiment, step 302 and step 304 can be completed by the transmitter of OLT, if Fig. 4 C shows, be One schematic diagram of the transmitter of OLT, the transmitter of OLT include: digital signal processor (digital signal Process, DSP), digital analog converter (analog-to-digital converter, ADC), driver, optical modulator and swash Light device.OLT generates the corresponding baseband signal of each ONU in numeric field, and baseband signal obtains after filtering out out of band signal by filter Target baseband signal, then to target baseband signal in numeric field multiplied by exp (j*2 π * f_t) realize frequency displacement, by each target base (f after corresponding downlink signal is obtained on the frequency translation of band signal to corresponding sub-band_tFor the center of ONU respective frequency sub-bands Frequency), these downlink signals are added, and obtain the frequency-division multiplex singal in electrical domain after converting by ADC, i.e., the described downlink frequency Divide multiplexed electrical signal.After downlink frequency division multiplexed electrical signal is amplified by driver, laser is loaded by optical modulator On the OLT transmitting light of sending, the frequency-division multiplex singal in area of light, i.e., the described downlink frequency division multiplexing optical signal are formed.

304, OLT sends downlink frequency division multiplexing optical signal.

After OLT generates downlink frequency division multiplexing optical signal, sent the downlink frequency division multiplexing optical signal to by ODN each ONU。

305, ONU by the intrinsic light of ONU of first frequency from obtained in downlink frequency division multiplexing optical signal the ONU it is corresponding under Row sub-band electric signal.

ONU by the set of frequency of the intrinsic light of ONU be first frequency after, when OLT send downlink frequency division multiplexing optical signal when, ONU carries out coherent reception by the intrinsic light of the ONU, and corresponding downlink sub-band letter is obtained from downlink frequency division multiplexing optical signal Number.

Specifically, above-mentioned steps 305 can be executed by the coherent receiver in ONU, be coherent receiver as shown in Figure 4 D A structural schematic diagram.Downlink frequency division multiplexing optical signal and the intrinsic photomixing of ONU, are converted to electricity after balanced detector detects Signal, this electric signal are moved downlink frequency division multiplexing optical signal to electrical domain base band, at this time centered on first frequency The corresponding multiple sub-bands of downlink frequency division multiplexing optical signal are distributed on the corresponding position of positive and negative frequency range, will be received using ADC Electric signal is transformed into numeric field, and obtains the corresponding downlink sub-band electric signal of the ONU by bandpass filtering treatment.

Secondly, in the embodiment of the present application, sub-band can be staggered distribution by OLT, effectively avoid the reflection of different sub-bands Signal brings interference to the sub-band information of upper and lower traveling optical signal.

Introduce the method for transmitting signals of PON system in the application from the angle of downlink transfer above, below uplink Angle introduces the method for transmitting signals of PON system in the application, referring to Fig. 5, method for transmitting signals in the embodiment of the present application One embodiment includes:

501, ONU carries out frequency displacement to baseband signal and obtains the corresponding uplink sub-band electric signal of ONU.

After ONU success is online, can start with OLT normal communication, OLT can be in the uplink sub-band (OLT point that ONU is registered The uplink sub-band of dispensing ONU) on send include uplink Dynamic Bandwidth Allocation message downlink data, ONU is according to upstream bandwidth Assignment messages can determine that OLT is the uplink sub-band of ONU distribution.After determining uplink sub-band, ONU can be used in electrical domain Radio-frequency modulations, that is, generate the corresponding baseband signal of the ONU, filters out the out of band signal in the baseband signal by filter, then Frequency displacement is carried out to the baseband signal for having filtered out out of band signal according to the uplink sub-band of distribution and obtains corresponding uplink sub-band electricity The uplink sub-band electric signal that signal, i.e. frequency displacement obtain is corresponding with the uplink sub-band of the ONU is distributed to.

502, uplink sub-band electric signal is loaded on ONU transmitting light and obtains uplink sub-band optical signal by ONU.

ONU is modulated after obtaining uplink sub-band electric signal, and uplink sub-band electric signal is loaded on ONU transmitting light by ONU Obtain uplink sub-band optical signal.

As a kind of optional mode, ONU emits light and is issued by the laser in ONU, and the laser is adjusted by TEC Frequency, and certain error will lead to by the frequency that TEC controls laser, that is, the frequency being arranged is inaccurate, this may lead There are crosstalks between the uplink optical signal for causing each ONU to modulate, and in order to avoid this crosstalk, this implementation is penetrated in electrical domain It after frequency modulation system, then is modulated in area of light, the centre frequency of signal that modulation obtains in this way is equal to the frequency of laser plus electricity The centre frequency of domain radiofrequency signal, the i.e. centre frequency of uplink sub-band optical signal are equal to the frequency of laser plus uplink son frequency The centre frequency of charged signal.Therefore, the present embodiment can pass through the centre frequency pair of the point signal of the uplink sub-band of modulation The frequency of laser compensates, and specifically, ONU carries out frequency displacement to baseband signal and obtains the corresponding uplink sub-band telecommunications of ONU Number, the centre frequency f of the uplink sub-band electric signal after frequency displacement₂=f-f₁Δ f, wherein f is the uplink that OLT distributes to the PNU The centre frequency of sub-band, f₁Emit the frequency of light for ONU, Δ f is the frequency error of laser, is specifically sent out by ONU according to OLT The downlink sub-band electric signal for giving the ONU is calculated by frequency excursion algorithm.

Specifically, above-mentioned steps 502 are executed by the receiver of ONU, are a structure of ONU receiver as shown in Figure 6A Schematic diagram, the ONU receiver include: DSP, ADC, driver, optical modulator and laser.ONU generates corresponding in numeric field Baseband signal filters out the out of band signal in baseband signal by filter, then in numeric field multiplied by exp (j*2 π * f₂) realize frequency It moves, obtains the sub-band signal in electrical domain, i.e. uplink sub-band electric signal, uplink sub-band telecommunications after then converting by ADC Number by driver amplify after, by optical modulator be loaded into laser sending ONU emit light on, formed area of light on son frequency Band signal, i.e. uplink sub-band optical signal.

503, ONU sends the corresponding uplink sub-band optical signal of ONU.

ONU sends the uplink sub-band optical signal to after area of light modulates to obtain uplink sub-band optical signal, through ODN OLT.The corresponding uplink sub-band optical signal of different uplink sub-bands that multiple ONU are issued is carried out multiplex and obtains uplink by wave multiplexer Frequency division multiplexing optical signal.It should be understood that different uplink sub-bands described in the present embodiment are not overlapped on frequency domain.

504, OLT obtains corresponding each uplink of uplink FDM optical signal by the intrinsic light of OLT of second frequency Frequency band electric signal.

In this implementation, second frequency is according to standard setting, and OLT is multiple ONU points centered on second frequency It is used in the uplink sub-band of uplink, i.e., in second frequency uplink FDM optical signal corresponding with this multiple ONU Frequency of heart alignment.OLT by uplink Dynamic Bandwidth Allocation message be each ONU distribute uplink sub-band after, each ONU according to divide Corresponding uplink sub-band electric signal is modulated and sent to the uplink sub-band matched, and each uplink sub-band electric signal is closed through wave multiplexer Uplink FDM optical signal is obtained after wave.OLT obtains the uplink FDM optical signal by the intrinsic light of OLT of second frequency Corresponding each uplink sub-band electric signal.

Specifically, above-mentioned steps 504 can be executed that (structure of coherent receiver can join by the coherent receiver in OLT See Fig. 4 D).Uplink FDM optical signal and the intrinsic photomixing of OLT, are converted to electric signal after balanced detector detects, this Electric signal is moved uplink FDM optical signal to electrical domain base band, at this time uplink frequency division centered on second frequency The corresponding multiple uplink sub-bands of multiplexing optical signal are distributed on the corresponding position of positive and negative frequency range, as shown in Figure 6B, will using ADC The corresponding uplink sub-band electric signal of this multiple uplink sub-band is transformed into numeric field, is then directed to each uplink sub-band telecommunications Number, by the uplink sub-band electric signal in numeric field multiplied by exp (j*2 π * f_t) realize frequency displacement (f_tUplink son frequency is corresponded to for each ONU The centre frequency of band), then filtered out the uplink sub-band electric signal to get the uplink without crosstalk is arrived using lowpass digital filter Sub-band electric signal, as shown in Figure 6 C.

As a kind of optional mode, in the corresponding embodiment of the method for above-mentioned Fig. 5, it is corresponding that above-mentioned Fig. 3 can also be performed in ONU The step 302 in above-mentioned Fig. 3 corresponding embodiment can also be performed to 304 in step 301 in embodiment and 305, OLT, i.e. OLT is also It can be each ONU allocation of downlink sub-band, generate multiple ONU and correspond to downlink frequency division multiplexed electrical signal, by downlink frequency division multiplex telecommunication It number is loaded on OLT transmitting light and obtains downlink frequency division multiplexing optical signal, and send the downlink frequency division multiplexing optical signal, and ONU meeting The set of frequency of the intrinsic light of ONU is first frequency by the downlink sub-band distributed according to OLT, then passes through the first frequency The intrinsic light of ONU obtains the corresponding downlink sub-band electric signal of the ONU from the downlink frequency division multiplexing optical signal that OLT is sent.I.e. originally In embodiment, OLT and ONU in PON system can carry out downlink biography by the method flow in above-mentioned Fig. 3 corresponding embodiment It is defeated, and uplink is carried out by the method flow in above-mentioned Fig. 5 corresponding embodiment.

As a kind of optional mode, when the OLT in PON system using the step 302 in above-mentioned Fig. 3 corresponding embodiment to 305 corresponding modes send downlink frequency division multiplexing optical signal, and using the corresponding mode of step 504 in Fig. 5 corresponding embodiment When obtaining the uplink sub-band electric signal that each ONU is sent, OLT is used for the transmitting light used when sending downlink frequency division multiplexing optical signal The intrinsic light (i.e. the intrinsic light of OLT) that (i.e. OLT emits light) and OLT are used to use when receiving uplink sub-band electric signal can be by same One light source issues, i.e. OLT emits light and the frequency of the intrinsic light of OLT is equal, i.e., the transmitter and receiver of OLT shares a light Source.

Similarly, when the ONU in PON system is using the step 501 in above-mentioned Fig. 5 corresponding embodiment to 503 corresponding sides Formula sends uplink sub-band electric signal, and step 301 and 305 corresponding modes in Fig. 3 corresponding embodiment is used to receive downlink When sub-band electric signal, the transmitting light (i.e. ONU emits light) and ONU that ONU is used to use when sending downlink sub-band electric signal are used The intrinsic light (i.e. the intrinsic light of ONU) used when receiving uplink sub-band electric signal can be issued by the same light source, i.e. ONU hair The frequency for penetrating light and the intrinsic light of ONU is equal, i.e., the transmitter and receiver of ONU shares a light source.

In the present embodiment, ONU can carry out radio-frequency modulations in electrical domain, compensate, make to the unstable of laser frequency It obtains optical network unit and issues stable optical signal, the string between uplink signal so as to avoid different optical network units transmissions It disturbs.

Secondly, OLT can receive the uplink signal of optical network unit transmission by way of relevant detection, i.e. optical link is whole End is only needed the centre frequency of intrinsic optical registration uplink FDM optical signal, it will be able to be obtained each optical network unit and be sent Uplink signal, it is easy to operate, it is at low cost.

The method for transmitting signals of PON system in the application is described above, the OLT in the application is introduced below, Referring to Fig. 7, one embodiment of OLT includes: in the application

Generation module 701, for generating the corresponding downlink frequency division multiplexed electrical signal of multiple downlink sub-bands, under the multiple Each downlink sub-band is not overlapped on frequency domain in row sub-band, and each downlink sub-band is corresponding with one group of optical network unit ONU；

Loading module 702 obtains downlink frequency division multiplexing for downlink frequency division multiplexed electrical signal to be loaded on OLT transmitting light Optical signal；

Sending module 703, for sending downlink frequency division multiplexing optical signal, so that the frequency of the intrinsic light of ONU is the first frequency The ONU of rate obtains the corresponding downlink sub-band signal of ONU from downlink frequency division multiplexing optical signal, first frequency and it is the multiple under One of downlink sub-band in row sub-band is corresponding.

Optionally, in the present embodiment, generation module 701 includes:

Submodule 7011 is generated, for generating the corresponding baseband signal of each ONU；

Shaping submodule block 7012, it is corresponding for obtaining each ONU to baseband signal progress shaping by low-pass filter Target baseband signal；

The corresponding target baseband signal frequency displacement of the ONU is obtained the ONU for being directed to each ONU by frequency displacement submodule 7013 The corresponding downlink sub-band signal of the ONU is obtained on corresponding downlink sub-band；

Merge submodule 7014, for merging the corresponding downlink sub-band signal of each ONU to obtain downlink frequency division multiplexing Electric signal.

Optionally, in the present embodiment, OLT further include:

Optionally, in the present embodiment, OLT can also include:

Determining module 704 is in idle condition or unregistered full for determining in the corresponding downlink sub-band of PON system Target sub-band, wherein the corresponding downlink sub-band of PON system is not overlapped on frequency domain；

Sending module 705, be also used on target sub-band send inquiry message, and pause in addition to target sub-band with Signal is sent on other outer frequency bands, so that ONU determines that first frequency, target sub-band are and ONU pairs according to inquiry message The downlink sub-band answered.

Optionally, in the present embodiment, OLT further include:

Module 706 is obtained, it is corresponding each to obtain uplink FDM optical signal for the intrinsic light of OLT by second frequency A uplink sub-band electric signal, second frequency is corresponding with the centre frequency of uplink FDM optical signal, uplink FDM light Signal is obtained signal after multiple uplink sub-band optical signal multiplex.Wherein, the intrinsic light of OLT and OLT transmitting light are unified light The light that source issues.

It should be understood that in above-mentioned Fig. 7 corresponding embodiment, performed process and earlier figures 3 and Fig. 5 between OLT modules Flow type in corresponding method embodiment, details are not described herein again.

In the embodiment of the present application, the corresponding downlink frequency division multiplexed electrical signal of multiple downlink frequencies is can be generated in generation module 701, Downlink frequency division multiplexed electrical signal is loaded on OLT transmitting light and obtains lower frequency division multiplexing optical signal, sending module by loading module 702 703 send the downlink frequency division multiplexing optical signal, and ONU can by coherent receiver using first frequency the intrinsic light of ONU from The corresponding downlink sub-band signal of ONU is obtained in downlink frequency division multiplexing optical signal, wherein first frequency and above-mentioned multiple downlink frequencies One of downlink sub-band in band is corresponding.In the embodiment of the present application, downlink frequency division multiplexed electrical signal is according on frequency domain What downlink signal on nonoverlapping multiple downlink sub-bands generated, each corresponding one group of ONU of downlink sub-band, i.e., different groups The occupied frequency band of the downlink signal that ONU is received is not overlapped, and there is no interference, is corresponded to so that ONU can accurately receive itself Downlink signal, improve the communication quality of user side.In addition, the embodiment of the present application is to modulate frequency-division multiplex singal in electrical domain, The frequency-division multiplex singal is loaded into transmitting light and passes to ONU, therefore, OLT only needs a laser that can modulate The corresponding sub-band signal of different ONU, does not need that multiple lasers are arranged, and does not need the light letter for issuing multiple and different wavelength yet Number, not only solved the problems, such as wavelength management difficulty, but also reduce device cost.

Secondly, in the embodiment of the present application, sub-band can be staggered distribution by distribution module, effectively avoid different sub-bands Reflection signal brings interference to the sub-band information of upper and lower traveling optical signal.

Again, in the embodiment of the present application, optical network unit hair can be received by way of relevant detection by obtaining module 706 The uplink signal sent, i.e. optical line terminal are only needed the centre frequency of intrinsic optical registration uplink FDM optical signal, energy The uplink signal that each optical network unit is sent enough is obtained, it is easy to operate, it is at low cost.

Present invention also provides a kind of OLT, referring to Fig. 8, another embodiment of OLT includes: in the application

Module 801 is obtained, it is corresponding each to obtain uplink FDM optical signal for the intrinsic light of OLT by second frequency A uplink sub-band electric signal, second frequency is corresponding with the centre frequency of uplink FDM optical signal, uplink FDM light Signal is obtained signal after multiple uplink sub-band optical signal multiplex.Wherein, the intrinsic light of OLT and OLT transmitting light are unified light The light that source issues.

Optionally, in the present embodiment, OLT can also include:

Distribution module 802, for using the first sub-band as uplink subband allocation to the optical-fiber network list in PON system Member, and using the second sub-band as downlink subband allocation to the optical network unit in PON system, wherein the first sub-band and Second sub-band is adjacent on frequency domain, that is to say, that for two sub-bands of arbitrary neighborhood on frequency domain, optical line terminal can be incited somebody to action It is one of to be used as uplink sub-band, using another as uplink sub-band.

Further, which can also include:

Submodule 8021 is determined, for determining in the corresponding downlink sub-band (i.e. first band) of PON system in the free time State or unregistered full target sub-band；

Sending submodule 8022 for sending inquiry message on target sub-band, and is paused in addition to target sub-band Signal is sent on other sub-bands in addition, so that optical network unit can be determined according to the inquiry message on target sub-band First frequency, and this target sub-band is exactly the downlink sub-band that optical line terminal distributes to the optical network unit, i.e. light net The downlink sub-band and target sub-band of network unit are corresponding.

In the embodiment of the present application, optical line terminal is only needed the center frequency of intrinsic optical registration uplink FDM optical signal Rate, it will be able to the uplink signal that each optical network unit is sent is obtained, it is easy to operate, it is at low cost.

Secondly, sub-band is staggered distribution by distribution module 802, it is possible to prevente effectively from the reflection signal of different sub-bands is to upper The sub-band information of downlink optical signal brings interference.

The ONU in the application is introduced below, referring to Fig. 9, one embodiment of ONU includes: in the application

Setup module 901, for being first frequency, first frequency and target sub-band by the set of frequency of the intrinsic light of ONU It is corresponding；

Receiving module 902, for obtaining ONU from downlink frequency division multiplexing optical signal by the intrinsic light of ONU of first frequency Corresponding downlink sub-band signal, downlink frequency division multiplexing optical signal are the OLT corresponding downlink frequency division multiplexing of multiple sub-bands is electric It being obtained in signal loading to OLT transmitting light, each downlink sub-band is not overlapped on frequency domain in the multiple downlink sub-band, The multiple downlink sub-band includes target sub-band.

Optionally, in the present embodiment, ONU can also include:

Adjustment module 903 for adjusting the frequency of the intrinsic light of ONU, and is directed to the intrinsic light of ONU of each frequency, to the ONU Intrinsic light and OLT carry out relevant detection in the inquiry message that target sub-band is sent, and determine the corresponding relevant detection of each frequency Output power；

Determining module 904, for determining, the corresponding frequency of maximum value is first frequency in relevant detection output power.

Optionally, in the present embodiment, ONU can also include:

Frequency displacement module 905 obtains the corresponding uplink sub-band electric signal of ONU, uplink for carrying out frequency displacement to baseband signal It is corresponding that the centre frequency of sub-band electric signal with OLT distributes to the uplink sub-band of ONU；

Loading module 906 obtains uplink sub-band light letter for uplink sub-band electric signal to be loaded on ONU transmitting light Number；

Sending module 907, for sending the corresponding uplink sub-band optical signal of ONU, so that passive wave multiplexer is to ONU pairs The uplink sub-band optical signal that other ONU are sent in the sub-band optical signal and PON system answered carries out multiplex and obtains uplink frequency division Multiplexing optical signal, OLT obtain the corresponding each uplink frequency of uplink FDM optical signal by the intrinsic light of OLT of second frequency Charged signal, second frequency are corresponding with the centre frequency of uplink FDM optical signal.

Specifically, the centre frequency of uplink sub-band electric signal distributes to that the uplink sub-band of ONU is corresponding to include: with OLT The centre frequency f of uplink sub-band electric signal₂=f-f₁Δ f, wherein f is the center for the uplink sub-band that OLT distributes to ONU Frequency, f₁Emit the frequency of light for ONU, Δ f is calculated according to downlink sub-band electric signal by frequency excursion algorithm Frequency deviation value.ONU emits light and the intrinsic light of ONU is the light that the same light source issues in ONU.

It should be understood that in above-mentioned Fig. 9 corresponding embodiment, performed process and earlier figures 3 and Fig. 5 between ONU modules Flow type in corresponding method embodiment, details are not described herein again.

In the embodiment of the present application, downlink frequency division multiplexed electrical signal is according to nonoverlapping multiple downlink sub-bands on frequency domain On downlink signal generate, each downlink sub-band corresponding one group of ONU, i.e., the downlink signal institute that different groups of ONU is received The frequency band of occupancy is not overlapped, and there is no interference, so that ONU can accurately receive itself corresponding downlink signal, improves user The communication quality of side.Frequency-division multiplex singal is modulated in electrical domain in addition, being originally achieved in that, which is loaded into hair It penetrates and passes to ONU in light, therefore, OLT only needs a laser that can modulate the corresponding sub-band signal of different ONU, It does not need that multiple lasers are arranged, does not need the optical signal for issuing multiple and different wavelength yet, both solved wavelength management difficulty Problem, and reduce device cost.

Secondly, ONU can carry out radio-frequency modulations in electrical domain, the unstable of laser frequency is compensated, so that light net Network unit issues stable optical signal, the crosstalk between uplink signal so as to avoid different optical network units transmissions.

Present invention also provides a kind of ONU, referring to Fig. 10, another embodiment of ONU includes: in the application

Frequency displacement module 1001 obtains the corresponding uplink sub-band electric signal of ONU, uplink for carrying out frequency displacement to baseband signal It is corresponding that the centre frequency of sub-band electric signal with OLT distributes to the uplink sub-band of ONU；

Loading module 1002 obtains uplink sub-band light for uplink sub-band electric signal to be loaded on ONU transmitting light Signal；

Sending module 1003, for sending the corresponding uplink sub-band optical signal of ONU, so that passive wave multiplexer is to ONU The uplink sub-band optical signal that other ONU are sent in corresponding sub-band optical signal and PON system carries out multiplex and obtains line frequency Divide multiplexing optical signal, OLT obtains corresponding each uplink of uplink FDM optical signal by the intrinsic light of OLT of second frequency Frequency band electric signal, second frequency are corresponding with the centre frequency of uplink FDM optical signal.

Optionally, in the present embodiment, the centre frequency and OLT of uplink sub-band electric signal distribute to the uplink son frequency of ONU With the corresponding centre frequency f for referring specifically to uplink sub-band electric signal₂=f-f₁Δ f, wherein f is optical line terminal distribution To the centre frequency of the uplink sub-band of optical network unit, f₁Emit the frequency of light for optical network unit, Δ f is according to downlink The frequency deviation value that frequency band electric signal is calculated by frequency excursion algorithm.

Optionally, in the present embodiment, ONU can also include:

Adjustment module 1004, for adjusting the frequency of the intrinsic light of optical network unit；

Determining module 1005, for being directed to the intrinsic light of optical network unit of each frequency, to the intrinsic light of the optical network unit Relevant detection is carried out in the inquiry message that target sub-band is sent with optical line terminal, determines the corresponding relevant detection of each frequency Output power, and the corresponding frequency of maximum value in relevant detection output power is determined as first frequency.

In the embodiment of the present application, ONU can carry out radio-frequency modulations in electrical domain, mend to the unstable of laser frequency Repay so that optical network unit issues stable optical signal, so as to avoid different optical network units from sending uplink signal it Between crosstalk.

OLT and ONU in the application are described from the angle of functional module above, below from the angle introduction of entity hardware OLT and ONU in the application, Figure 11 are the structural schematic diagrams of OLT or ONU of the embodiment of the present invention.OLT (ONU) 110 may include connecing Receipts machine 1110, transmitter 1120, processor 1130 and memory 1140.Memory 1140 may include read-only memory and random Memory is accessed, and provides instruction and data to processor 1130.The a part of of memory 1140 can also include non-volatile Random access memory (full name in English: Non-Volatile Random Access Memory, english abbreviation: NVRAM).

Memory 1140 stores following element, executable modules or data structures perhaps their subset or Their superset:

Operational order: including various operational orders, for realizing various operations.

Operating system: including various system programs, for realizing various basic businesses and the hardware based task of processing.

Processor 1130 is for the operational order in run memory 1140 in the embodiment of the present invention, so that OLT or ONU It executes such as the step in above-mentioned Fig. 3 or Fig. 5 corresponding method embodiment.

The embodiment of the present application also provide can a kind of PON system, the PON system include one such as above-mentioned Fig. 7 corresponding embodiment In OLT and multiple ONU as in above-mentioned Figure 11 corresponding embodiment.

The embodiment of the present application also provides a kind of PON system, which includes one such as above-mentioned Fig. 9 corresponding embodiment In OLT and multiple ONU as in above-mentioned Figure 10 corresponding embodiment.

The application in order to facilitate understanding is illustrated below with a concrete scene example, please refers to Figure 12, and the application is implemented PON system in example includes: OLT transmitter, ONU coherent receiver, ONU transmitter and OLT coherent receiver.

OLT transmitter is the modulation of full bandwidth frequency division multiplexing, using single laser light source, by loading frequency in external modulator Divide multiplexing electrical modulation signal, realizes frequency division multiplexing optical signal modulation.Each sub-band signal of frequency division multiplexing optical signal passes through OLT The ONU of specific array is distributed to, every group of ONU occupies sub- rate peak bandwidth.Certain frequency can be reserved between each sub-band Rate interval guaranteeing between each sub-band without crosstalk, or can use electrical domain filter shape, and the signal outside sub-band is complete It filters out entirely, effectively avoids the crosstalk between sub-band.

ONU coherent receiver is selected using intrinsic laser device subbands signal.Utilize the frequency of intrinsic laser device And the correlation between temperature, the output light frequency of intrinsic laser device is controlled by adjusting temperature.By the frequency of intrinsic laser device It is directed at the corresponding frequency subband of respective ONU, can choose required sub-band information, is moved to electrical domain fundamental frequency and carries out DSP Processing judgement.Since peak rate declines, sub- rate coherent receiver bandwidth of a device is reduced to sub-band bandwidth, effectively filters out institute Need the invalid information outside sub-bands of frequencies.

ONU rate transmitter is modulated using sub-band, by loading sub-band radiofrequency signal in external modulator, effectively Reduce transmitter bandwidth demand.It is multiple that mostly band frequency division is merged into the sub-band signal uplink of each ONU after passive wave multiplexer Use signal.The sub- rate transmitter of ONU end and the intrinsic shared same light source of coherent receiver, on the one hand effectively reduce cost, another Aspect is effectively ensured the sub- rate modulation frequency location of uplink and precisely aligned, avoided by intrinsic source alignment downlink subband wavelength Frequency interband crosstalk is generated after multiplex.

OLT is using full rate coherent receiver to mostly band frequency-division multiplex singal (the i.e. uplink FDM after uplink multiplex Optical signal) it is detected.The end OLT full rate coherent receiver is intrinsic to share same light source with OLT transmitter, is effectively reduced into This, while guaranteeing that intrinsic light source frequency is effectively directed at uplink mostly with the centre frequency of frequency-division multiplex singal, to full range band signal into Row detection.

Above-mentioned PON system is modulated by frequency division multiplexing and sub- rate coherent reception, significantly reduces unicast high speed PON system The side ONU bandwidth of a device demand in system, is substantially improved the receiving sensitivity of unicast high speed PON system, has low cost, high power pre- The advantages of calculation, can effectively be applied in next-generation high-capacity and high-speed PON system.

Further, it in above-mentioned PON system, is allocated by the sub-band to uplink and downlink signals, so that uplink and downlink The sub-band of signal light account for odd even purpose frequency band respectively and effectively avoid difference using the frequency selective characteristic of coherent reception The reflection signal of frequency band brings interference to the sub-band information on upper and lower traveling optical signal.

ONU relevant to sub- rate low cost, the reception of the sub- rate signal of downlink are carried out by adjusting the frequency of intrinsic light source The selection of subband signal.And the modulation of the sub- rate signal of uplink is modulated using high-frequency radio frequency, and subband signal is loaded into accordingly On sub-band.

Further, in above-mentioned PON system, uplink transmitting light is aligned with downlink reception subband, it is contemplated that TEC control swashs There are certain error (1.25GHz) for light device frequency, precisely align to guarantee that ONU uplink modulates each subband, avoid each son after multiplex Band frequency band generates aliasing, causes crosstalk, and the frequency adjustment using innovation based on radio-frequency modulations carries out uplink subband center frequency It precisely aligns.The intrinsic light of ONU downlink coherent reception, which shares, emits light for uplink, since TEC controls error, intrinsic light (transmitting Light) and required subband between there are the frequency departure of Δ f, Δ f in downlink subband signal after coherent reception machine testing, Ke Yitong The frequency excursion algorithm for crossing DSP is calculated.To avoid uplink subband from modulating the subband signal that the frequency departure causes different ONU Aliasing occurs after multiplex, in the modulation of uplink subband, rf-signal modulation, radio-frequency modulations frequency are carried out to electrical domain modulated signal It needs to subtract Δ f on the basis of the original, to compensate the influence of laser frequency departure.The frequency f modulated₂=f-f₁Δ f, F is the centre frequency of uplink sub-band, f₁For the frequency for emitting light (intrinsic light).

In the above-described embodiments, can come wholly or partly by software, hardware, firmware or any combination thereof real It is existing.When implemented in software, it can entirely or partly realize in the form of a computer program product.

The computer program product includes one or more computer instructions.Load and execute on computers the meter When calculation machine program instruction, entirely or partly generate according to process or function described in the embodiment of the present invention.The computer can To be general purpose computer, special purpose computer, computer network or other programmable devices.The computer instruction can be deposited Storage in a computer-readable storage medium, or from a computer readable storage medium to another computer readable storage medium Transmission, for example, the computer instruction can pass through wired (example from a web-site, computer, server or data center Such as coaxial cable, optical fiber, Digital Subscriber Line (DSL)) or wireless (such as infrared, wireless, microwave) mode to another website Website, computer, server or data center are transmitted.The computer readable storage medium can be computer and can deposit Any usable medium of storage either includes that the data storages such as one or more usable mediums integrated server, data center are set It is standby.The usable medium can be magnetic medium, (for example, floppy disk, hard disk, tape), optical medium (for example, DVD) or partly lead Body medium (such as solid state hard disk Solid State Disk (SSD)) etc..

It is apparent to those skilled in the art that for convenience and simplicity of description, the system of foregoing description, The specific work process of device and unit, can refer to corresponding processes in the foregoing method embodiment, and details are not described herein.

In several embodiments provided herein, it should be understood that disclosed system, device and method can be with It realizes by another way.For example, the apparatus embodiments described above are merely exemplary, for example, the unit It divides, only a kind of logical function partition, there may be another division manner in actual implementation, such as multiple units or components It can be combined or can be integrated into another system, or some features can be ignored or not executed.Another point, it is shown or The mutual coupling, direct-coupling or communication connection discussed can be through some interfaces, the indirect coupling of device or unit It closes or communicates to connect, can be electrical property, mechanical or other forms.

The unit as illustrated by the separation member may or may not be physically separated, aobvious as unit The component shown may or may not be physical unit, it can and it is in one place, or may be distributed over multiple In network unit.It can select some or all of unit therein according to the actual needs to realize the mesh of this embodiment scheme 's.

It, can also be in addition, each functional unit in each embodiment of the application can integrate in one processing unit It is that each unit physically exists alone, can also be integrated in one unit with two or more units.Above-mentioned integrated list Member both can take the form of hardware realization, can also realize in the form of software functional units.

If the integrated unit is realized in the form of SFU software functional unit and sells or use as independent product When, it can store in a computer readable storage medium.Based on this understanding, the technical solution of the application is substantially The all or part of the part that contributes to existing technology or the technical solution can be in the form of software products in other words It embodies, which is stored in a storage medium, including some instructions are used so that a computer Equipment (can be personal computer, server or the network equipment etc.) executes the complete of each embodiment the method for the application Portion or part steps.And storage medium above-mentioned includes: USB flash disk, mobile hard disk, read-only memory (full name in English: Read-Only Memory, english abbreviation: ROM), random access memory (full name in English: Random Access Memory, english abbreviation: RAM), the various media that can store program code such as magnetic or disk.

The above, above embodiments are only to illustrate the technical solution of the application, rather than its limitations；Although referring to before Embodiment is stated the application is described in detail, those skilled in the art should understand that: it still can be to preceding Technical solution documented by each embodiment is stated to modify or equivalent replacement of some of the technical features；And these It modifies or replaces, the spirit and scope of each embodiment technical solution of the application that it does not separate the essence of the corresponding technical solution.

Claims

1. a kind of method for transmitting signals of passive optical network PON system, which is characterized in that the described method includes:

Optical line terminal OLT generates the corresponding downlink frequency division multiplexed electrical signal of multiple downlink sub-bands, the multiple downlink frequency Each downlink sub-band is not overlapped on frequency domain in band, and each downlink sub-band is corresponding with one group of optical network unit ONU；

The downlink frequency division multiplexed electrical signal is loaded on OLT transmitting light and obtains downlink frequency division multiplexing optical signal by the OLT；

The OLT sends the downlink frequency division multiplexing optical signal so that the frequency of the intrinsic light of ONU be first frequency ONU from Obtain the corresponding downlink sub-band signal of the ONU in the downlink frequency division multiplexing optical signal, the first frequency and described more One of downlink sub-band in a downlink sub-band is corresponding.

2. the method according to claim 1, wherein the OLT generates the corresponding downlink of multiple downlink sub-bands Frequency division multiplexing electric signal includes:

The OLT generates the corresponding baseband signal of each ONU；

The OLT carries out shaping to the baseband signal by low-pass filter and obtains the corresponding target baseband signal of each ONU；

For each ONU, the corresponding target baseband signal frequency displacement of the ONU is obtained the corresponding downlink sub-band of the ONU by the OLT On obtain the corresponding downlink sub-band signal of the ONU；

The OLT merges the corresponding downlink sub-band signal of each ONU to obtain downlink frequency division multiplexed electrical signal.

3. the method according to claim 1, wherein the OLT generates the corresponding downlink of multiple downlink sub-bands Include: before frequency division multiplexing electric signal

The OLT is determined to be in idle condition or unregistered full mesh in the corresponding downlink sub-band of passive optical network PON system Mark sub-band, wherein the corresponding downlink sub-band of the PON system is not overlapped on frequency domain；

The OLT sends inquiry message on the target sub-band, and pauses at its other than the target sub-band He sends signal on frequency band, so that the ONU determines the first frequency, the target sub-band according to the inquiry message For downlink sub-band corresponding with the ONU.

4. the method according to claim 1, wherein the OLT generates the corresponding downlink of multiple downlink sub-bands Include: before frequency division multiplexing electric signal

The OLT using the first sub-band as uplink subband allocation to the ONU in PON system, and using the second sub-band as Downlink subband allocation is to the ONU in the PON system, first sub-band and the second sub-band phase on frequency domain It is adjacent.

5. method according to claim 1 to 4, which is characterized in that the method also includes:

The OLT obtains the corresponding each uplink sub-band of uplink FDM optical signal by the intrinsic light of OLT of second frequency Electric signal, the second frequency is corresponding with the centre frequency of the uplink FDM optical signal, the uplink FDM light Signal is obtained signal after multiple uplink sub-band optical signal multiplex.

6. according to the method described in claim 5, it is characterized in that, OLT transmitting light and the intrinsic light of the OLT are described The light that the same light source issues in OLT.

7. a kind of method for transmitting signals of passive optical network PON system, which is characterized in that the described method includes:

The set of frequency of the intrinsic light of ONU is first frequency by ONU, and the first frequency is corresponding with target sub-band；

It is corresponding that the ONU by the intrinsic light of ONU of the first frequency obtains the ONU from downlink frequency division multiplexing optical signal Downlink sub-band signal, the downlink frequency division multiplexing optical signal are the OLT by the corresponding downlink frequency division multiplexing of multiple sub-bands Electric signal is loaded on OLT transmitting light and obtains, and in the multiple downlink sub-band each downlink sub-band does not weigh on frequency domain Folded, the multiple downlink sub-band includes the target sub-band.

8. the method according to the description of claim 7 is characterized in that the set of frequency of the intrinsic light of ONU is the first frequency by the ONU Include: before rate

The ONU adjusts the frequency of the intrinsic light of ONU, and is directed to the intrinsic light of ONU of each frequency, exists to the intrinsic light of the ONU and OLT The inquiry message that target sub-band is sent carries out relevant detection, determines the corresponding relevant detection output power of each frequency；

The ONU determines that the corresponding frequency of maximum value is the first frequency in the relevant detection output power.

9. method according to claim 7 or 8, which is characterized in that the method also includes:

The ONU carries out frequency displacement to baseband signal and obtains the corresponding uplink sub-band electric signal of the ONU, the uplink sub-band It is corresponding that the centre frequency of electric signal with the OLT distributes to the uplink sub-band of the ONU；

The uplink sub-band electric signal is loaded on ONU transmitting light and obtains uplink sub-band optical signal by the ONU；

The ONU sends the corresponding uplink sub-band optical signal of the ONU, so that passive wave multiplexer is corresponding to the ONU The uplink sub-band optical signal that other ONU are sent in sub-band optical signal and the PON system carries out multiplex and obtains uplink frequency division Multiplexing optical signal, the OLT obtain the corresponding each uplink of uplink FDM optical signal by the intrinsic light of OLT of second frequency Sub-band electric signal, the second frequency are corresponding with the centre frequency of the uplink FDM optical signal.

10. according to the method described in claim 9, it is characterized in that, centre frequency and the institute of the uplink sub-band electric signal It states OLT and distributes to the uplink sub-band correspondence of the ONU and include:

The centre frequency f of the uplink sub-band electric signal₂=f-f₁Δ f, wherein the f is described in the OLT is distributed to The centre frequency of the uplink sub-band of ONU, the f₁Emit the frequency of light for the ONU, the Δ f is according to downlink The frequency deviation value that frequency band electric signal is calculated by frequency excursion algorithm.

11. according to the method described in claim 9, it is characterized in that, ONU transmitting light and the intrinsic light of the ONU are described The light that the same light source issues in ONU.

12. a kind of optical line terminal OLT, which is characterized in that the described method includes:

Generation module, for generating the corresponding downlink frequency division multiplexed electrical signal of multiple downlink sub-bands, the multiple downlink frequency Each downlink sub-band is not overlapped on frequency domain in band, and each downlink sub-band is corresponding with one group of ONU；

Loading module obtains downlink frequency division multiplexed optical for the downlink frequency division multiplexed electrical signal to be loaded on OLT transmitting light Signal；

Sending module, for sending the downlink frequency division multiplexing optical signal, so that the frequency of the intrinsic light of ONU is first frequency ONU obtains the corresponding downlink sub-band signal of the ONU, the first frequency and institute from the downlink frequency division multiplexing optical signal The one of downlink sub-band stated in multiple downlink sub-bands is corresponding.

13. OLT according to claim 12, which is characterized in that the generation module includes:

Shaping submodule block obtains the corresponding target of each ONU for carrying out shaping to the baseband signal by low-pass filter Baseband signal；

Frequency displacement submodule, for be directed to each ONU, by the corresponding target baseband signal frequency displacement of the ONU obtain the ONU it is corresponding under The corresponding downlink sub-band signal of the ONU is obtained on row sub-band；

Merge submodule, for merging the corresponding downlink sub-band signal of each ONU to obtain downlink frequency division multiplexed electrical signal.

14. OLT according to claim 12 or 13, which is characterized in that the OLT further include:

Receiving module obtains the corresponding each uplink of uplink FDM optical signal for the intrinsic light of OLT by second frequency Sub-band electric signal, the second frequency is corresponding with the centre frequency of the uplink FDM optical signal, the uplink frequency division Multiplexing optical signal is obtained signal after multiple uplink sub-band optical signal multiplex.

15. OLT according to claim 14, which is characterized in that the OLT emits light and the intrinsic light of the OLT is described The light that the same light source issues in OLT.

16. a kind of optical network unit ONU, which is characterized in that the described method includes:

Setup module, for being first frequency, the first frequency and target sub-band pair by the set of frequency of the intrinsic light of ONU It answers；

Receiving module obtains the ONU from downlink frequency division multiplexing optical signal for the intrinsic light of ONU by the first frequency Corresponding downlink sub-band signal, the downlink frequency division multiplexing optical signal are the OLT by the corresponding downlink frequency of multiple sub-bands Point multiplexed electrical signal, which is loaded into, to be obtained on OLT transmitting light, and each downlink sub-band is in frequency domain in the multiple downlink sub-band On be not overlapped, the multiple downlink sub-band includes the target sub-band.

17. ONU according to claim 16, which is characterized in that the ONU further include:

Frequency displacement module obtains the corresponding uplink sub-band electric signal of the ONU, the uplink for carrying out frequency displacement to baseband signal It is corresponding that the centre frequency of sub-band electric signal with the OLT distributes to the uplink sub-band of the ONU；

Loading module obtains uplink sub-band optical signal for the uplink sub-band electric signal to be loaded on ONU transmitting light；

Sending module, for sending the corresponding uplink sub-band optical signal of the ONU, so that passive wave multiplexer is to the ONU The uplink sub-band optical signal that other ONU are sent in corresponding sub-band optical signal and PON system carries out multiplex and obtains line frequency Point multiplexing optical signal, the OLT by the intrinsic light of OLT of second frequency obtain uplink FDM optical signal it is corresponding it is each on Row sub-band electric signal, the second frequency are corresponding with the centre frequency of the uplink FDM optical signal.

18. ONU according to claim 17, which is characterized in that the centre frequency of the uplink sub-band electric signal and institute It states OLT and distributes to the uplink sub-band correspondence of the ONU and include:

19. ONU according to claim 17, which is characterized in that the ONU emits light and the intrinsic light of the ONU is described The light that the same light source issues in ONU.

20. a kind of PON system, which is characterized in that the PON system includes such as described in any item OLT of claim 12 to 15, And such as the described in any item ONU of claim 16 to 19.