WO2011110005A1

WO2011110005A1 - Passive optical network and device

Info

Publication number: WO2011110005A1
Application number: PCT/CN2010/076400
Authority: WO
Inventors: 叶飞
Original assignee: 华为技术有限公司
Priority date: 2010-08-27
Filing date: 2010-08-27
Publication date: 2011-09-15
Also published as: CN102959983B; CN102959983A

Abstract

A passive optical network system, including an optical line terminal, a remote node device and multiple optical network units, is provided by the present invention. Said optical line terminal connects to said remote node device via a trunk fiber. Said multiple optical network units are divided into multiple groups. Said remote node device includes multiple ports. Each port corresponds to one group of optical network units respectively, and connects to said group of optical network units in point-to-multipoint manner. The wavelength division multiplexing manner is used between different groups of optical network units for communicating with said optical line terminal. The time division multiplexing manner is used by the optical network units in one group for communicating with said optical line terminal. Said optical line terminal includes an interface module, a first receiving module and a second receiving module. Said interface module connects to said trunk fiber, and couples to said first receiving module and second receiving module via a splitter. Wherein, the receiving wavelength channel of said first receiving module and the receiving wavelength channel of said second receiving module are complementary with each other. Further, a passive optical network device is provided by the present invention.

Description

PASSIVE OPTICAL NETWORK SYSTEM AND APPARATUS FIELD OF THE INVENTION The present invention generally relates to the field of optical access network technologies, and in particular, to a passive optical network (PON) system and device. BACKGROUND OF THE INVENTION With the "light into copper retreat" gradually becoming the mainstream access mode of network technology, the application of optical access network (OAN) technology, especially passive optical network (PON) technology, has been vigorously developed.

The traditional PON system is a point-to-multipoint network system, which mainly adopts a tree topology and uses Time Division Multiplexing (TDM) mechanism to communicate between the central office and the client. Referring to FIG. 1 , the existing TDM PON system includes an optical line terminal (OLT) located at the office side, and multiple optical network units (ONUs) located on the user side and connected to the optical line. Optical Distributing Network (ODN) between the terminal and the optical network unit. The OLT provides a network side interface for the PON system; the ONU provides a user side interface for the PON system; the ODN is used to distribute or multiplex data signals between the OLT and the ONU, so that the A plurality of ONU elements may share an optical transmission channel, and the ODN may include a passive optical splitting device for optical branching, which is connected to the OLT through a trunk optical fiber, and is respectively connected to the plurality of ONUs through a plurality of branch optical fibers . In the PON system, the direction from the OLT to the ONU is called downlink, and the OLT broadcasts the downlink data stream to all ONUs according to the time division multiplexing mode, and each ONU receives only the data with its own identity. The direction from the ONU to the OLT is uplink. Since the ONUs share the optical transmission channel, the PON system uses Time Division Multiple Access (TDMA) in the uplink direction to ensure that the uplink data of each ONU does not collide. A time slot is allocated to each ONU by the OLT, and each ONU sends uplink data strictly according to the time slot allocated by the OLT.

The existing TDM PON system imposes a significant limitation on the number of ONUs due to the use of ODN for optical splitting in the downstream direction and the allocation of time slots for individual ONUs in a single wavelength in the upstream direction, and on the other hand , which limits the available bandwidth of each user and wastes the available bandwidth of the fiber itself, so it cannot meet the needs of the emerging broadband network application service.

To solve the above I problem and consider compatibility with existing TDM PON systems, the industry provides a hybrid PON system combining Wavelength Division Multiplexing (WDM) and TDM technologies. Specifically, the hybrid PON system includes a plurality of TDM subsystems, and the plurality of TDM subsystems share an optical line terminal OLT. Each of the TDM subsystems employs different uplink and downlink operating wavelengths, and the plurality of TDM subsystems are coupled to a transmitting fiber using wavelength division multiplexing. In addition, the OLT is internally configured with a plurality of transceiver modules, each transceiver module corresponding to a TDM subsystem, and the plurality of transceiver modules are respectively coupled to the transmission fiber by a wavelength division multiplexing/demultiplexing device to implement Communication between the system is performed by the transmitting fiber and its corresponding TDM.

However, as shown in FIG. 2, the passband of the wavelength division multiplexing/demultiplexer is generally in the form of a comb, that is, there is a stop band between the adjacent two passbands, and in actual operation, the ONU is The upstream wavelength may be affected by the external environment (such as temperature) and drift. If the upstream wavelength of an ONU drifts to a stop band between the passband of the wavelength division multiplexer/demultiplexer, the uplink data sent by the ONU will be filtered out and cannot be received by the OLT. As a result, the ONU is not working properly. Summary of the invention

In view of this, embodiments of the present invention provide a passive optical network system and device that can solve the above problems. The embodiment of the present invention first provides a passive optical network system, including an optical line terminal, a remote node device, and a plurality of optical network units, where the optical line terminal is connected to the remote node device through a backbone optical fiber, where the multiple The optical network unit is divided into multiple groups, and the remote node device includes multiple ports, each of which corresponds to a group optical network unit, and is connected to the group of optical network units by point-to-multipoint, and different groups of optical network units The optical line terminal communicates with the optical line terminal by using a wavelength division multiplexing method, and the same group of optical network units communicates with the optical line terminal by using a time division multiplexing manner, where the optical line terminal includes an interface module, a first receiving module, and a second a receiving module, the interface module is connected to the trunk fiber and coupled to the first receiving module and the second receiving module by a beam splitter, wherein the receiving wavelength channel of the first receiving module and the second receiving module The receiving wavelength channels are complementary.

The embodiment of the present invention further provides an optical line terminal device, which includes an interface module and a receiving device, where the receiving device includes a beam splitter, a first receiving module, and a first receiving module; the interface module respectively passes through the optical splitter And coupled to the first receiving module and the first receiving module, and configured to receive multiple sets of uplink signals respectively from multiple groups of optical network units and transmitted by wavelength division multiplexing, where each group of uplink signals passes through multiple time divisions And transmitting, by the optical splitter, the plurality of sets of uplink signals received by the interface module, and performing the same to the first receiving module and the second receiving module, where the first receiving The receive wavelength channel of the module is complementary to the receive wavelength channel of the second receive module.

The embodiment of the present invention further provides an optical access system, including an optical line terminal, a remote node device, and a plurality of time division multiplexing TDM subsystems, where the remote node device is connected to the optical line through a trunk optical fiber. Each of the TDM subsystems includes at least one optical network unit, and the optical network unit of the same TDM subsystem is connected to the remote node device through an optical distribution network, where each TDM subsystem corresponds to one wavelength channel, And the different TDM subsystems are in communication with the optical line terminal by using a wavelength division multiplexing manner, where the optical line terminal includes an interface module, a first receiving module, and a second receiving module, where the interface module is connected to the trunk optical fiber. And receiving an uplink signal from the optical network unit of the multiple TDM subsystems, and forwarding the uplink signal to the first receiving module and the second receiving module, where the receiving of the first receiving module The channel is complementary to the receive channel of the second receiving module.

The technical solution provided by the embodiment of the present invention is configured with two receiving modules in the central optical line terminal of the passive optical network system, and the wavelength channels of the two receiving modules are complementary. Based on the above-mentioned wavelength channel configuration, the receiving device inside the optical line terminal can realize a continuous seamless passband by the mutual cooperation of the first receiving module and the second receiving module, thereby implementing transmission to the optical network unit. The uplink signal is received seamlessly or without blind spots. Therefore, according to the technical solution provided by the embodiment of the present invention, even if the uplink wavelength of the optical network unit on the user side of the passive optical network system is drifted due to the influence of the external environment, for example, drifting to the stop band of one of the receiving modules, The uplink signal transmitted by the optical network unit can still be received by the second receiving module in the optical line terminal, thereby ensuring normal operation of the passive optical network system. BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are set forth in the claims

FIG. 1 is a schematic structural diagram of a conventional time division multiplexing passive optical network system.

Fig. 2 is a schematic diagram showing the passband of the wavelength division multiplexing/demultiplexing device of the optical line terminal of the passive optical network system shown in Fig. 1.

FIG. 3 is a schematic structural diagram of a hybrid passive optical network system according to an embodiment of the present invention;

4 is a schematic diagram of a passband of a first demultiplexer and a second demultiplexer of an optical line termination of the passive optical network system shown in FIG.

FIG. 5 is a schematic diagram of a data plane structure of a medium access control module of an optical line terminal of the passive optical network system shown in FIG. 3.

6 is a schematic diagram showing the PLOAM layer structure of the medium access control module of the optical line terminal of the passive optical network system shown in FIG.

7 is a DBA level of a medium access control module of an optical line terminal of the passive optical network system shown in FIG. Schematic. DETAILED DESCRIPTION OF THE EMBODIMENTS In order to make the objects, technical solutions and advantages of the present invention more comprehensible, the present invention will be further described in detail below with reference to the embodiments and drawings. The illustrative embodiments of the present invention and the description thereof are intended to explain the present invention, but are not intended to limit the invention.

Embodiments of the present invention first provide a hybrid passive optical network system that can achieve seamless reception. Please refer to FIG. 3 , which is a schematic structural diagram of an embodiment of a passive optical network (PON) system provided by the present invention. The PON system 300 is a hybrid PON system combining wavelength division multiplexing (WDM) technology and time division multiplexing (TDM) technology, and functionally speaking, a user side device (such as an optical network unit) of the hybrid PON system 300 The upstream wavelength can be dynamically changed. That is, the correspondence between the optical network unit and the wavelength channel can be dynamically changed. Therefore, it may be referred to as a Dynamic Spectrum Management (DSM) PON system, that is, a DSM PON system.

The PON system 300 can include an optical line terminal (OLT) 310 located at a central office (CO), a relay device 320 at a remote node (RN), and N TDM subsystems.

330, wherein the relay device 320 is connected to the optical line terminal through the trunk fiber 340 in the uplink direction.

310, and connected to the one TDM subsystem 330 in the downstream direction, respectively.

This embodiment is described by taking Ν = 4 (that is, the hybrid system includes four TDM subsystems) as an example. For convenience of description, the four TDM subsystems 330 are respectively recorded as the first TDM subsystem, Two TDM subsystems, a third TDM subsystem, and a fourth TDM subsystem. In addition, in order to make the illustration clearer and more concise, FIG. 3 only shows the specific structure of one of the TDM subsystems (ie, the third TDM subsystem), and for other

The TDM subsystem is only schematically represented; however, it should be understood that those skilled in the art can understand the specific network architecture of the system 300 and implement the specific implementation provided by the embodiments of the present invention according to the description of FIG. 3 and the following description.

Each TDM subsystem 330 includes an optical distribution network (ODN) 331 and a plurality of optical network units, respectively.

332, the optical distribution network 331 includes a secondary trunk fiber 337, a plurality of branch fibers 338, and at least one passive optical splitting device (such as a splitter Splitter) 339. The passive optical splitting device 339 is connected between the secondary trunk optical fiber 337 and the plurality of branch optical fibers 338, and is connected to the relay device 320 through the secondary trunk optical fiber 337 on the one hand, and A plurality of branch fibers 338 are correspondingly connected to the plurality of optical network units 332. It should be understood that the concept of the so-called "TDM subsystem 330" introduced in this specification is only for The description will be made clearer and the logic will be clearer, so that those skilled in the art can better understand the solution provided by the embodiment. The concept of the above-mentioned "TDM subsystem 330" can be understood as follows: In the PON system 300, the plurality of optical network units 332 are grouped according to their correspondingly connected optical distribution networks 331 and belong to the same group after grouping. One or more of the optical network elements 332 and their corresponding optical distribution networks 331 (and other network elements or devices) are divided into a so-called TDM subsystem. That is, the PON system 300 includes N optical distribution networks 331 and M optical network units 332. The M optical network units 332 are divided into N groups, and each group of optical network units 332 includes at least one optical network unit. 332, and connected to the relay device 320 through a corresponding optical distribution network 331, respectively. The number of the optical network units 332 of each group may be equal or different, and may be determined according to actual network conditions.

In this embodiment, the N TDM subsystems 330 communicate with the optical line terminal 310 through a wavelength division multiplexing (WDM) mechanism, thereby implementing sharing of the trunk optical fibers 340, and thus belonging to different TDM sub-children. The optical network unit 332 of system 330 can simultaneously transmit uplink data. Moreover, each TDM subsystem 330 internally adopts a time division multiplexing mechanism, so that its internal optical network unit 332 shares the secondary trunk fibers 337. Specifically, each TDM subsystem 330 corresponds to a pair of uplink/downlink wavelengths, respectively. For example, in the downlink direction, the optical line terminal 310 implements communication with the TDM subsystem 330 by using the downlink wavelength. Specifically, based on the downlink wavelength, the optical line terminal 310 performs downlink according to a time division multiplexing manner. The data stream is broadcast to the optical network unit 332 of the TDM subsystem 330. Each optical network unit 332 receives only data with its own identity; and in the uplink direction, multiple optical network units 332 of the TDM subsystem 330 are employed. The upstream wavelength enables communication with the optical line terminal 310, and the TDM subsystem 330 employs a time division multiple access TDMA mechanism in the upstream direction, that is, the optical line terminal 310 is internal to the TDM subsystem 330. Each optical network unit 332 allocates time slots, and each optical network unit 332 is sent in strict accordance with the time slot allocated by the optical line terminal 310. Uplink data.

In addition, in the TDM subsystem 330, the optical network unit 332 may be an optical network unit (GPON ONU) of a Gigabit passive optical network, an optical network unit (EPON ONU) of an Ethernet passive optical network, and an XGPON. The ONU or the 10G EPON ONU, that is, the PON system 300 provided by the embodiment of the present invention can be compatible with the optical network unit of the existing Time Division Multiplexed Passive Optical Network (TDM PON) system.

The relay device 320 includes a wavelength division multiplexing/demultiplexing module 321 , and the wavelength division multiplexing/demultiplexing module 321 includes N ports, and each port is respectively connected to one TDM subsystem 330. Specifically, each port may be connected to the passive optical splitting device 339 through a secondary trunk optical fiber 337 of the corresponding optical distribution network 331 and further connected to the TDM through a plurality of branch optical fibers 338 of the optical distribution network 331 In subsystem 330 A plurality of optical network units 332.

The optical line termination 310 includes a controller 311, a transmitting device 312, a receiving device 313, and an interface module 314. The controller 31 1 may be a Media Access Control (MAC) module (the MAC module is taken as an example in this embodiment), and is connected to the transmitting device 312 and the receiving device 313. The downlink signal transmission and the uplink signal reception of the transmitting device 312 and the receiving device 313 are separately controlled. The interface module 314 can be a wavelength division multiplexing (WDM) coupler that is also coupled to the transmitting device 312 and the receiving device 313 for wavelength coupling the transmitting device 312 and the receiving device 313 to the The backbone fiber 340 is described such that downlink signals transmitted by the transmitting device 312 can be transmitted to the TDM subsystem 330 through the backbone fiber 340 and the relay device 320, and from the optical network unit in each TDM subsystem 330 The uplink signal transmitted by 332 can be transmitted to the receiving device 313 through the relay device 320 and the backbone fiber 340.

Transmitting device 312 can include N transmitting units 51 1 and a wavelength division multiplexer 512. The N transmitting units 51 1 are connected to the beam splitting module 430 through the wavelength division multiplexer 512. For convenience of description, the N transmitting units 51 1 are schematically recorded as TxA, respectively. TxB, TxC and TxD (as shown in Figure 3). Each of the transmitting units 511 corresponds to a TDM subsystem 330, and the wavelength division multiplexer 512 is configured to perform wavelength division multiplexing on the downlink signals sent by the N transmitting units 511, and further pass the interface. Module 314 outputs to backbone fiber 340 such that optical network unit 332 in its corresponding TDM subsystem 330 can receive the downstream signal through a corresponding optical distribution network 331.

The receiving device 313 can include a first receiving module 410, a second receiving module 420, and a beam splitting module 430. The first receiving module 410 and the second receiving module 420 are connected to the interface module 341 by the optical splitting module 430, wherein the optical splitting module 430 is configured to perform spectral processing on the uplink signal received by the interface module 341. And providing the first receiving module 410 and the second receiving module 420 respectively.

The first receiving module 410 includes N first receiving units 411 and a first demultiplexer 412. The N first receiving units 411 are connected to the optical splitting module 430 by the first demultiplexer 412. For convenience of description, the N first receiving units 41 1 are respectively used in this embodiment. As described, N=4) in the present embodiment is schematically recorded as RxA0, RxB0, RxCO, and RxD0. The first demultiplexer 412 may be an Array waveguide grate (AWG) for performing wave decomposition multiplexing on uplink signals from the plurality of TDM subsystems 330, and further providing the corresponding A receiving unit RxA0, RxBO, RxCO and RxD0.

Referring to FIG. 4, the passband of the first demultiplexer 412 has a comb structure. Specifically, the passband of the first demultiplexer 412 includes N subbands (as described above, this implementation For example, N=4), which are respectively referred to as a first sub-band RxA, a second sub-band RxB, a third sub-band RxC, and a fourth sub-band RxD, and the sub-bands RxA R RxD Inter-spaced, that is, there are stop bands between adjacent two sub-bands (such as RxA/RxB, RxB/RxC or RxC/RxD, etc.). Each of the sub-bands RxA R RxD corresponds to one receiving unit RxA0 R RxD0, that is, the receiving units RxAO R RxDO can respectively receive uplink signals whose wavelengths fall in their corresponding sub-bands RxA R RxD. In a specific embodiment, the widths of the strips RxA R RxD may be substantially equal, for example, the width of each strip may correspond to a spectral width of 50 GHz, respectively, and the width of the stop band between two adjacent sub-bands is also It can correspond to a spectral width of 50 GHz, respectively.

Similarly, the second receiving module 420 includes N second receiving units 421 and a second demultiplexer 422. The N second receiving units 421 are connected to the optical splitting module 430 by the second demultiplexer 422. For convenience of description, the N second receiving units 421 are respectively schematically recorded in this embodiment. It is RxAl, RxBK RxCl and RxDl. The second demultiplexer 422 may also be an arrayed waveguide grating (AWG) for performing wave decomposition multiplexing of uplink signals from the plurality of TDM subsystems 330 and further providing corresponding second reception. Unit 421.

Referring to FIG. 4 together, the passband of the second demultiplexer 422 also has a comb structure. Specifically, the passband of the second demultiplexer 422 also includes N subbands, which are respectively recorded as follows. The fifth sub-band RxE, the sixth sub-band RxF, the seventh sub-band RxG, and the eighth sub-band RxH, and the sub-bands RxE R RxH are spaced apart from each other, that is, there is a stop band between the adjacent two sub-bands. Each of the sub-bands RxE R RxF corresponds to one receiving unit RxAl RxD1, that is, the receiving units Rx A 1 R RxD 1 can respectively receive uplink signals whose wavelengths fall in their corresponding sub-bands Rx E R RxF. In a specific embodiment, the widths of the sub-bands RxA R RxD may be substantially equal. For example, each sub-band may respectively correspond to a spectral width of 50 GHz, and the widths of the stop bands between adjacent two sub-bands may also correspond respectively. The spectral width at 50 GHz.

In this embodiment, the passbands of the first demultiplexer 412 and the second demultiplexer 422 are complementary to implement the first receiving module 410 and the second receiving module 420. The receiving wavelengths are complementary. Specifically, as shown in FIG. 4, in the passband of the second demultiplexer 422, each of the subbands RxE to RxF respectively correspond to the adjacent subbands RxAl to RxD1 of the first demultiplexer 412. The stop band between. Based on the above-mentioned wavelength passband configuration, the receiving device 313 can realize a continuous seamless passband by the mutual cooperation of the first receiving module 410 and the second receiving module 420, whereby the optical line terminal 310 The uplink signals sent by the respective optical network units 332 can be seamlessly or blindly received by the first receiving module 410 and the second receiving module 420. Therefore, even if the wavelength of the uplink signal drifts to the stop band of the first demultiplexer 412 due to the influence of the external environment, it can be received by the corresponding receiving unit 421 of the second receiving module 420, thereby ensuring the The normal operation of the PON system 300. It should be understood that in the actual product, the first demultiplexer 412 There may be partial overlap between the passbands of the second demultiplexer 422 and the passband of the second demultiplexer 422, but it is preferable to ensure that the area of overlap is small in the actual product as much as possible.

Further, in a specific embodiment, the first receiving units RxA0, RxB0, RxCO, and RxDO and the second receiving units RxAl, RxB1, RxCl, and RxD1 may be divided into four pairs, and each pair of receiving units respectively One of the first receiving units RxA0, RxB0, RxCO or RxDO of the first receiving module 410 and one of the second receiving units RxAl, RxB1, RxCl or RxD1 of the second receiving module 420, and the same pair of receiving units The corresponding wavelength channels are adjacent. For example, in one embodiment, RxAO and RxAl, RxBO and RxBl, RxCO and RxCl, RxDO and RxDl may each form a pair of receiving units. Moreover, each pair of receiving units can be configured to receive an uplink signal transmitted by an optical network unit 332 of a TDM subsystem 330. If there is an overlapping area of the wavelength passband corresponding to the same pair of receiving units, when the transmitting wavelength of the optical network unit 332 of the TDM subsystem 330 drifts to the overlapping area, the two receiving units are received from the The uplink signal of the optical network unit 332, in this case, the MAC module 31 1 can select the receiving unit with good reception effect according to the error rate to receive the uplink signal.

The passband configuration of the first demultiplexer 412 and the second demultiplexer 422, i.e., the receive wavelength channel configuration of the first receive module 410 and the second receive module 420, are exemplarily described below by way of an example. It should be understood that the following examples are merely an alternative to implement the present invention, and other configurations may be employed in practical applications.

The reference wavelengths of the first demultiplexer 412 and the second demultiplexer 422 are both 1270 nanometers (nm), and the two respectively comprise four wavelength channels, wherein each wavelength channel is a sub-band, and each The relative spectral channels correspond to a spectral width of 50 GHz. Referring to the table below, for ease of understanding, the following table uses relative wavelengths to represent the wavelength channels of the demultiplexers 412 and 422. As shown in the following table, in an embodiment, the relative wavelength channels of the first demultiplexer 412 may be 25 GHz to 75 GHz, 125 GHz to 175 GHz, 225 GHz to 275 GHz, and 325 GHz to 375 GHz, respectively; The relative wavelength channels of the multiplexer 422 may be 75 GHz to 125 GHz, 175 GHz to 225 GHz, 275 GHz to 325 GHz, and 375 GHz to 425 GHz, respectively.

In addition, the actual wavelength channel is a reference wavelength + a relative wavelength channel. For example, the wavelength channel 1 of the first demultiplexer 412 is 1270 nm + 25 GHz to 1270 nm + 75 GHz (wherein the conversion relationship between the unit of wavelength nm and GHz) It is known to those skilled in the art).

Further, in order to better understand the present invention, the optical network unit 332 of the TDM subsystem 330 is an optical network unit (GPON ONU) of a gigabit passive optical network as an example, and the structure of the controller 311 is performed. Illustratively stated. Referring to FIG. 5 to FIG. 7 , in the embodiment, when the optical network unit 332 is a GPON ONU, the MAC module 311 is at the data layer and physical layer operation (Administration and Maintenance, PLOAM) level. Schematic diagram of the Dynamic Bandwidth Allocation (DBA) layer.

In Figs. 5 to 7, RxA0 to RxD0 and RxAl to RxD1 respectively denote receiving units of the first receiving module 410 and the second receiving module 420 of the receiving device 313, and Tx denotes a transmitting unit of the transmitting device 312. As described above, RxA0 to RxD0 and RxAl to RxDl are divided into four groups each of which includes a first receiving unit RxA0 to RxD0 adjacent to the wavelength channel and a second receiving unit RxAl to: RxD1. Specifically, in the present embodiment, RxAO and RxAl, RxBO and RxBl, RxCO and RxCl, RxDO and RxDl can be respectively divided into groups.

The MAC module 311 includes a plurality of uplink GTC demapping modules UGTCR1 UGTCR4 and a downlink GTC framing module DGTCT. Each of the uplink GTC demapping modules UGTCR1 to UGTCT4 is respectively connected to the group receiving unit, and is configured to perform uplink frame synchronization, scrambling code or FEC decoding, and uplink frame header of the uplink GTC frame received by the group receiving unit. Processing, processing of GEM frames/PLOAM frames/DBRu frames, etc. Furthermore, the downlink GTC framing module DGTCT is mainly used for downlink GTC frame header processing, GEM frame/PLOAM frame/B WMAP, etc. to form a GTC frame, FEC/scrambling code, and the like.

Referring to FIG. 5, at the data level, the MAC module 31 1 further includes multiple uplink GEM deframing modules.

UGEMR1~UGEMR4, downlink GEM framing module DGEMT and Ethernet interface module ETH. Each of the uplink GEM demapping modules UGEMR 1 to UGEMR4 is respectively connected to an uplink GTC demapping module UGTCR1 UGTCR4 for performing GEM frame header processing on the uplink GEM frame forwarded by the uplink GTC demapping module UGTCR1 UGTCR4 , GEM load (ie data) extraction / assembly / forwarding. The downlink GEM framing module DGEMT is mainly used to implement downlink GEM frame header processing, data slicing/assembly, and the like. The Ethernet interface module ETH is mainly used to provide the MAC module 311 with an interface with a network side hardware transceiver.

Referring to FIG. 6, at the PLOAM level, the MAC module 31 1 further includes a PLOAM module and an ONU registration module. The PLOAM module is connected to the uplink GTC demapping module UGTCR 1 -UGTCR4 and the downlink GTC framing module DGTCT, and is mainly used for processing PLOAM frames. Please refer to Figure 7, at the DBA level, The MAC module 31 1 further includes a DBA module, and the DBA module is connected to the uplink GTC de-frame module UGTCR1 UGTCR4 and the downlink GTC framing module DGTCT, and is mainly used to implement an uplink dynamic bandwidth allocation function module, according to the uplink traffic. The monitoring information or the bandwidth requirement report of the ONU, and the relationship between the ONU and the uplink channel, respectively calculate the bandwidth allocation result on the four uplink channels, and then assemble the BWMAP. And the PLOAM module and the DBA module are both connected to the ONU registration module, wherein the ONU registration module implements functions such as registration management and ONU state maintenance of the ONU through the PLO AM module and the DBA. It can be seen from the MAC structure of FIG. 6 and FIG. 7 that in the PON system 300 provided in this embodiment, the optical line terminal 310 can implement the multiple TDM sub-substation through the PLOAM module, the DBA module, and the ONU module. The optical network unit of system 330 performs PLOAM processing, DBA scheduling, and ONU management and maintenance in a unified manner. The PON system and the OLT device provided by the embodiments of the present invention are briefly summarized as follows: The embodiment of the present invention provides a passive optical network system, including an optical line terminal, a remote node device, and multiple optical network units, where the light The line terminal is connected to the remote node device by a backbone fiber, and the plurality of optical network units are divided into multiple groups, and the remote node device includes multiple ports, each port corresponding to a group of optical network units, and A multi-point mode is connected to the group of optical network units, and different groups of optical network units are used to communicate with the optical line terminal by using wavelength division multiplexing, and the same group of optical network units adopts time division multiplexing mode and the optical line terminal. Communication, the optical line terminal includes an interface module, a first receiving module, and a second receiving module, the interface module is coupled to the trunk fiber and coupled to the first receiving module and the second receiving module by a beam splitter, where The receiving wavelength channel of the first receiving module is complementary to the receiving wavelength channel of the second receiving module.

The receiving wavelength channel of the first receiving module and the receiving wavelength channel of the second receiving module may be complementary: the receiving wavelength channel of the first receiving module and the receiving wavelength channel of the second receiving module are substantially not Overlapping one another, and one just covers a certain preset wavelength channel.

The first receiving module includes a plurality of mutually spaced first receiving wavelength channels, the first receiving module includes a plurality of second receiving wavelength channels that are spaced apart from each other, and the second receiving wavelength channel is disposed at the plurality of The spacing of the first receiving wavelength channels from each other.

In an embodiment, the first receiving module includes a plurality of first receiving units and a first demultiplexer, and each of the first receiving units respectively corresponds to a group of optical network units, and the first demultiplexing The device is configured to perform wave decomposition multiplexing on the uplink signals from the multiple groups of optical network units and respectively provide them to the corresponding first receiving unit, where the first demultiplexer includes multiple first wavelength channels that are spaced apart from each other. Band, each first wavelength passband It does not correspond to one of the receiving wavelength channels of the first receiving module.

In an embodiment, the second receiving module includes a plurality of second receiving units and a second demultiplexer, and each of the second receiving units respectively corresponds to a group of optical network units, and the second demultiplexer is used. And performing uplink demultiplexing on the uplink signals from each group of optical network units and respectively providing them to the corresponding second receiving unit, where the first demultiplexer includes a plurality of second wavelength passbands spaced apart from each other, each The second wavelength passbands respectively correspond to one of the receiving wavelength channels of the second receiving module, and the second wavelength passband is located at a stop band between the first wavelength passbands of the first demultiplexer .

In a specific embodiment, the first demultiplexer and the second demultiplexer are waveguide array gratings; the plurality of first wavelength passbands have the same width, and the plurality of first wavelengths The width of the stop band between the pass bands is equal.

In an embodiment, the optical line terminal further includes a media access control module, where the media access control module is configured to control the physical layer operation management and maintenance PLOAM processing and dynamics uniformly for the multiple groups of optical network units. Bandwidth allocation. Further, an embodiment of the present invention further provides an optical line terminal device, including an interface module and a receiving device, where the receiving device includes a beam splitter, a receiving module, and a second receiving module; The splitters are respectively coupled to the first receiving module and the second receiving module, and are configured to receive multiple sets of uplink signals respectively from multiple groups of optical network units and transmitted by wavelength division multiplexing, where each group is uplinked The signal is transmitted by using a time division multiple access method; the optical splitter is configured to perform spectral processing on the plurality of sets of uplink signals received by the interface module, and simultaneously provide the first receiving module and the second receiving module, where The receiving wavelength channel of the first receiving module is complementary to the receiving wavelength channel of the second receiving module.

In an embodiment, the receiving module includes a plurality of receiving units and a plurality of demultiplexers, each of the first receiving units respectively corresponding to a group of optical network units, and the first The device is configured to perform wave decomposition multiplexing on the uplink signals from the multiple groups of optical network units and respectively provide the corresponding signals to the corresponding first receiving unit, where the first demultiplexer includes a plurality of first wavelengths spaced apart from each other The passband, each of the first wavelength passbands respectively corresponds to one of the receiving wavelength channels of the first receiving module.

In an embodiment, the second receiving module includes a plurality of second receiving units and a second demultiplexer, and each of the second receiving units respectively corresponds to a group of optical network units, and the second demultiplexer is used. And performing uplink demultiplexing on the uplink signals from each group of optical network units and respectively providing them to the corresponding second receiving unit, where the first demultiplexer includes a plurality of second wavelength passbands spaced apart from each other, each Second wavelength passbands respectively correspond One of the second receiving modules receives a wavelength channel, and the second wavelength passband is located at a stop band between the first wavelength passbands of the first demultiplexer.

In an embodiment, the optical line terminal device may further include a media access control module, where the media access control module is configured to perform unified physical layer operation management and maintenance PLOAM processing on the plurality of optical network units. And dynamic bandwidth allocation.

In a specific embodiment, the optical line termination device is applied to a dynamic spectrum management passive optical network DSM PON system. Further, an embodiment of the present invention further provides an optical access system, including an optical line terminal, a remote node device, and a plurality of time division multiplexing TDM subsystems, where the remote node device is connected to the light through a main ten optical fiber. a line terminal, each TDM subsystem includes at least one optical network unit, and an optical network unit of the same TDM subsystem is connected to the remote node device through an optical distribution network, where each TDM subsystem corresponds to a wavelength Channels, and different TDM subsystems communicate with the optical line terminal by wavelength division multiplexing, the optical line terminal includes an interface module, a first receiving module, and a second receiving module, and the interface module is connected to the trunk An optical fiber, configured to receive an uplink signal from the optical network unit of the multiple TDM subsystems, and forward the uplink signal to the first receiving module and the second receiving module, where the first receiving module The receiving channel is complementary to the receiving channel of the second receiving module.

In an embodiment, the first receiving module includes a plurality of first receiving units, each of the first receiving units respectively corresponding to a receiving channel, and different receiving channels corresponding to the receiving unit are different; The second receiving module includes a plurality of second receiving units, each of the second receiving units respectively corresponding to one receiving channel, the receiving channels corresponding to different second receiving units are different, and the receiving channels of the plurality of second receiving units are The receiving channels of the plurality of 'receiving units' do not overlap.

In an embodiment, the first receiving module further includes a first wave decomposition multiplexer, configured to perform wave decomposition multiplexing on the uplink signals forwarded by the interface module, and respectively provide the uplink signals to the corresponding first receiving unit. The first wave decomposition multiplexer includes a plurality of mutually spaced wavelength passbands, each of the wavelength passbands respectively corresponding to a receiving channel of one of the first receiving units of the first receiving module.

In an embodiment, the second receiving module further includes a second wave decomposition multiplexer, configured to perform wave decomposition multiplexing on the uplink signals forwarded by the interface module, and respectively provide the uplink signals to the corresponding second receiving unit. The second wave decomposition multiplexer includes a plurality of mutually spaced wavelength passbands, each of the wavelength passbands respectively corresponding to a receiving channel of one of the second receiving units of the second receiving module, and the Two-wave decomposition multiplexer The wavelength passband is located in the stop band between the wavelength passbands of the first wave decomposition multiplexer. Through the description of the above embodiments, those skilled in the art can clearly understand that the present invention can be implemented by means of software plus a necessary hardware platform, and of course, can also be implemented entirely by hardware. Based on such understanding, all or part of the technical solution of the present invention contributing to the background art may be embodied in the form of a software product, which may be stored in a storage medium such as a ROM/RAM, a magnetic disk, an optical disk, or the like. A number of instructions are included to cause a computer device (which may be a personal computer, server, or network device, etc.) to perform the methods described in various embodiments of the present invention or portions of the embodiments. The above is only a preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily think of changes or within the technical scope of the present disclosure. Alternatives are intended to be covered by the scope of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

Rights request

A passive optical network system, comprising: an optical line terminal, a remote node device, and a plurality of optical network units, wherein the optical line terminal is connected to the remote node device by a trunk optical fiber, the plurality of lights The network unit is divided into multiple groups, and the remote node device includes multiple ports, each port corresponding to a group of optical network units, and connected to the group of optical network units by point-to-multipoint, and different groups of optical network units The optical line unit communicates with the optical line terminal by using a wavelength division multiplexing method, and the same group of optical network units communicates with the optical line terminal by using a time division multiplexing manner, where the optical line terminal includes an interface module, a first receiving module, and a second receiving a module, the interface module is connected to the trunk fiber and coupled to the first receiving module and the second receiving module by a beam splitter, wherein a receiving wavelength channel of the receiving module and a second receiving module The receiving wavelength channels are complementary.

2. The passive optical network system according to claim 1, wherein the first receiving module comprises a plurality of receiving and receiving units and a plurality of demultiplexers, and each of the receiving and receiving units respectively corresponds to a group optical network unit, the first demultiplexer is configured to perform wave decomposition multiplexing on the uplink signals from the multiple groups of optical network units, and respectively provide the uplink signals to the corresponding first receiving unit, where the first solution The multiplexer includes a plurality of first wavelength passbands spaced apart from each other, and each of the first wavelength passbands respectively corresponds to one of the receive wavelength channels of the first 'receiving module.

The passive optical network system according to claim 2, wherein the second receiving module comprises a plurality of second receiving units and a second demultiplexer, and each of the second receiving units respectively corresponds to The second optical multiplexer is configured to perform wave decomposition multiplexing on the uplink signals from each group of optical network units and respectively provide them to corresponding second receiving units, where the first demultiplexer And comprising a plurality of second wavelength passbands spaced apart from each other, each of the second wavelength passbands respectively corresponding to one of the receiving wavelength channels of the second receiving module, and the first wavelength passband is located in the first solution A stop band between the passbands of the first wavelength of the multiplexer.

4. The passive optical network system according to claim 3, wherein the first demultiplexer and the second demultiplexer are waveguide array gratings.

The passive optical network system according to claim 3, wherein the plurality of first wavelength passbands have the same width and the width of the stopband between the plurality of first wavelength passbands equal.

The passive optical network system according to claim 3, wherein the optical line terminal further comprises a medium access control module, and the medium access control module is configured to control the plurality of optical network units Unified physical layer operation management maintains PLO AM processing and dynamic bandwidth allocation.

An optical line terminal device, comprising: an interface module and a receiving device, wherein the receiving device comprises a beam splitter, a first receiving module and a second receiving module; wherein the interface module is respectively coupled by the optical splitter To the first receiving module and the second receiving module, and configured to receive multiple sets of uplink signals respectively from multiple groups of optical network units and transmitted by wavelength division multiplexing, wherein each group of uplink signals passes time division multiple access And transmitting, by the optical splitter, the plurality of sets of uplink signals received by the interface module are spectrally processed and simultaneously provided to the first receiving module and the second receiving module, where the first receiving module The receiving wavelength channel is complementary to the receiving wavelength channel of the second receiving module.

The passive optical network system according to claim 7, wherein the first receiving module comprises a plurality of first receiving units and a first demultiplexer, and each of the first receiving units respectively corresponds to one The first optical multiplexer is configured to perform wave decomposition multiplexing on the uplink signals from the plurality of optical network units and respectively provide the uplink signals to the corresponding first receiving unit, where the first The processor includes a plurality of first wavelength passbands spaced apart from each other, each of the first wavelength passbands respectively corresponding to one of the receive wavelength channels of the first receiving module.

The passive optical network system according to claim 8, wherein the second receiving module comprises a plurality of second receiving units and a second demultiplexer, and each of the second receiving units respectively corresponds to one The second demultiplexer is configured to perform wave decomposition multiplexing on the uplink signals from each group of optical network units and respectively provide the corresponding signals to the corresponding second receiving unit, where the first demultiplexer includes a plurality of second wavelength passbands spaced apart from each other, each of the second wavelength passbands respectively corresponding to one of the receive wavelength channels of the second receiving module, and the second wavelength passband is located in the first demultiplexing The stop band between the first wavelength passbands of the device.

The optical line terminal device according to claim 7, further comprising a medium access control module, wherein the medium access control module is configured to control the physical layer operation uniformly on the plurality of optical network units Manage and maintain PLOAM processing and dynamic bandwidth allocation.

The optical line terminal device according to claim 7, wherein the optical line terminal device is applied to a dynamic spectrum management passive optical network DSM PON system.

12. An optical access system, comprising: an optical line terminal, a remote node device, and a plurality of time division multiplexed TDM subsystems, wherein the remote node device is connected to the optical line terminal through a trunk optical fiber, each TDM The subsystems respectively comprise at least one optical network unit, and the optical network units of the same TDM subsystem are connected to the remote node device through an optical distribution network, wherein each TDM subsystem corresponds to one wavelength channel and different TDM subsystems Communicating with the optical line terminal by using a wavelength division multiplexing manner, where the optical line terminal includes an interface module, a first receiving module, and a second receiving module, where the interface module is connected to the trunk optical fiber. And receiving an uplink signal from the optical network unit of the multiple TDM subsystems, and forwarding the uplink signal to the first receiving module and the second receiving module, where the receiving of the first receiving module The channel is complementary to the receive channel of the second receiving module.

The optical access system according to claim 12, wherein the first receiving module comprises a plurality of first receiving units, each of the first receiving units respectively corresponding to one receiving channel, and different first receiving The receiving channel corresponding to the unit is different; the second receiving module includes a plurality of second receiving units, each of the second receiving units respectively corresponding to one receiving channel, and the receiving channels corresponding to different second receiving units are different, and the The receiving channels of the plurality of second receiving units do not overlap with the receiving channels of the plurality of first receiving units.

The optical access system according to claim 13, wherein the first receiving module further comprises a first wave decomposition multiplexer, configured to perform wave decomposition on the uplink signal forwarded by the interface module. And respectively provided to the corresponding first receiving unit, wherein the first wave decomposition multiplexer comprises a plurality of mutually spaced wavelength passbands, each of the wavelength passbands respectively corresponding to one of the first receiving modules A receiving channel of a receiving unit.

The optical access system according to claim 14, wherein the second receiving module further comprises a second wave decomposition multiplexer, configured to perform wave decomposition on the uplink signal forwarded by the interface module. And respectively provided to the corresponding second receiving unit, wherein the second wave splitting multiplexer comprises a plurality of mutually spaced wavelength passbands, each of the wavelength passbands respectively corresponding to one of the second receiving modules And a receiving channel of the receiving unit, and a wavelength passband of the second wave decomposition multiplexer is located in a stop band between the wavelength passbands of the first wave decomposition multiplexer.