CN104080018A - TWDM-PON transmission system with load aggregating and energy-saving functions - Google Patents

Abstract

The present invention provides a TWDM-PON transmission system with load aggregation and energy-saving functions, including: several subsystems and a first periodic arrayed waveguide grating; each subsystem is connected in parallel through the first periodic arrayed waveguide grating; the subsystems include Downlink adjustable transmitter device, uplink data processing device, first optical circulator, optical amplifier, feeder type optical fiber, splitter combiner and optical network unit; wherein, the downlink adjustable transmitter device passes through the first periodic The arrayed waveguide grating is connected to the first end of the first optical circulator; the third end of the first optical circulator is respectively connected to the optical network unit through the optical amplifier, the feeder fiber, and the splitter and combiner; the uplink data processing device is respectively Connect the second end of the first optical circulator. The invention adopts the periodic arrayed waveguide grating passive device, realizes load aggregation and dynamic wavelength routing in the TWDM-PON system structure, is compatible with the existing TWDM-PON network, and reduces system energy consumption.

Description

TWDM-PON Transmission System with Load Aggregation and Energy Saving Functions

technical field

The invention relates to the technical field of optical communication, in particular to a TWDM-PON transmission system based on a periodic arrayed waveguide grating with functions of load aggregation and energy saving.

Background technique

With the development of communication technology and the diversification of people's needs, a large number of new services are emerging, including ultra-high-definition image and video transmission, cloud computing, cloud storage, data centers, etc., which put forward higher requirements for network capacity. At the same time, in modern urban life, people work in the city's CBD during the day and return to residential areas to rest at night, which triggers the "tidal effect" of large-scale migration of communication data traffic. During the day, the data traffic is concentrated in the urban CBD, and the data traffic in the residential area is very small, and the network bandwidth resources are not fully utilized; at night, the data traffic is concentrated in the residential area, and the data traffic in the urban CBD is very small. It has caused a large amount of idle bandwidth resources and cannot be utilized. Moreover, whether in the CBD or residential areas, emergencies or hotspots may cause local data traffic to surge, which will lead to network congestion and inability to access. Therefore, on the one hand, the network is faced with a situation where resources are idle and cannot be utilized, resulting in waste. On the other hand, when a large number of data requests are burst locally, the network resources are insufficient and the network is blocked, and the needs of users cannot be met. To sum up, it is necessary to find a new network system structure to respond to real-time data flow requirements, dynamically allocate network bandwidth resources, and realize reasonable scheduling of network resources, so as to meet user needs to the greatest extent.

The TWDM-PON system transmission structure with load aggregation and energy-saving functions based on periodic arrayed waveguide gratings is a new structure composed of AWGR devices configured in the traditional TWDM-PON network. The passive optical network TWDM-PON based on time-division multiplexing and wavelength-division multiplexing stacking is considered to be the main development direction of NG-PON2 because of its relatively low implementation cost and good compatibility (without changing the existing ODN network structure). . However, in a common TWDM-PON system, the network bandwidth resource is fixed and cannot respond at any time according to the demand, but this is an important issue to realize network load aggregation.

Periodic Arrayed Waveguide Grating AWGR (Arrayed Wavelength Grating Router) is a group of AWG arrays. The AWGR device is configured into the TWDM-PON system as a passive module. The system structure is simple, and the AWGR device is compatible with the traditional TWDM-PON system. Arrayed waveguide grating has an important application in wavelength division multiplexing technology. Periodic arrayed waveguide grating can realize multiplexing and demultiplexing of multi-wavelength light. Therefore, AWGR can be introduced into TWDM-PON system. At present, there are relatively few literatures on the transmission structure of the TWDM-PON system with load aggregation and energy-saving functions based on periodic arrayed waveguide gratings. And the previous TWDM-PON system structure based on the periodic arrayed waveguide grating cannot load aggregation.

According to the existing literature search, Huawei Ning Cheng, Lei Wang and others published "Flexible TWDM PON with Load Balancing and Power Saving" at the 2013 European Conference On Optical Communication (ECOC). In this document, the author proposes a flexible TWDM-PON system capable of load balancing and energy saving. In order to achieve load balancing in the network, the author proposes a new flexible TWDM-PON structure, which includes an optical line terminal (OLT) transceiver and a hybrid AWG/Splitter. Through the 4×4 mixed AWG/Splitter and adjustable transceiver module, wavelength deployment is performed on the same ODN or between different ODNs to achieve network load balancing. In this structure, a hybrid structure of Cyclic AWG and Power Splitter is designed to realize wavelength routing, which realizes resource scheduling and load balancing. However, this structure is for distributing loads on different wavelengths, which is not conducive to energy saving of the system. In addition, The structure proposed by Huawei is relatively complicated, which brings unnecessary troubles in the process of network construction, maintenance and upgrade.

Contents of the invention

In view of the defects in the prior art, the object of the present invention is to provide a TWDM-PON system transmission device with load aggregation and energy saving functions.

According to the TWDM-PON transmission system with load aggregation and energy-saving functions provided by the present invention, it includes: several subsystems and a first periodic arrayed waveguide grating; several subsystems are connected in parallel through the first periodic arrayed waveguide grating;

The subsystem includes a downlink adjustable transmitter device, an uplink data processing device, a first optical circulator, an optical amplifier, a feeder optical fiber, a splitter combiner, and an optical network unit;

Wherein, the downlink adjustable transmitter device is connected to the first end of the first optical circulator through the first periodic arrayed waveguide grating; The combiner is connected to the optical network unit; the uplink data processing device is respectively connected to the second end of the first optical circulator.

Preferably, the downlink adjustable transmitter device includes several downlink adjustable transmitter modules, a second periodic arrayed waveguide grating, and a dispersion/chirp management unit;

Wherein, several downlink adjustable transmitter modules are respectively connected to the input end of the dispersion/chirp management unit through the second periodic arrayed waveguide grating, and the output end of the dispersion/chirp management unit is connected to the first periodic Arrayed Waveguide Grating.

Preferably, the several uplink data processing devices include several uplink data processing units, several photodetectors, a third periodic arrayed waveguide grating, and a dispersion/chirp management unit;

Wherein, several uplink data processing units are respectively connected to the output end of the third periodic arrayed waveguide grating through a photodetector, and the second end of the first optical circulator is connected to the third periodic arrayed waveguide grating through a dispersion/chirp management unit. The input end of the periodic arrayed waveguide grating.

Preferably, the optical network unit includes a second optical circulator, an adjustable filter, a receiver, and an uplink adjustable transmitter;

Wherein, the second port of the second optical circulator is connected to the splitter/combiner through a distributed optical fiber, and the third port of the second optical circulator is connected to the receiver through an adjustable filter; The output of the modulation transmitter is connected to the first port of the second optical circulator.

Preferably, the splitter combiner includes an optical splitter and an optical combiner; the optical splitter is used to distribute the downlink signal to each optical network unit connected to it through the optical splitter, and the optical combiner is used to combine the optical network unit Uplink signals are coupled.

Preferably, the first periodic arrayed waveguide grating adopts an N*N type periodic arrayed waveguide grating; the second periodic arrayed waveguide grating and the third periodic arrayed waveguide grating adopt a 1*N type periodic arrayed waveguide grating, where N is 2 ⁿ , n is a natural number greater than 2.

Preferably, the downlink transmitter is modular and adjustable, and the tuning range is from tuned to in, is the mth downlink wavelength, is the mth downstream wavelength after modulation, m is 2 ⁿ , n is a natural number greater than 2, and d represents the downstream.

Preferably, both the downlink adjustable transmitter module and the uplink data processing unit are M in number, M is 2 ⁿ , and n is a natural number greater than 2.

Preferably, the adjustable filter adopts a band-pass filter or a periodic filter.

Compared with the prior art, the present invention has the following beneficial effects:

1. The present invention uses periodic arrayed waveguide gratings to perform dynamic wavelength routing and realize network load aggregation;

2. The periodic arrayed waveguide grating in the present invention is well compatible with the traditional TWDM-PON system, and is easy to upgrade and transform on the basis of the existing network;

3. The present invention has a simple structure, and can realize load aggregation not only in a single sub-passive network, but also in different subsystems; when the data traffic in the network is small, the traffic can be concentrated on certain wavelengths , so that the remaining wavelengths can be idle and the transmitter can be turned off, which not only makes full use of the bandwidth resources in the network but also achieves the purpose of energy saving.

Description of drawings

Other characteristics, objects and advantages of the present invention will become more apparent by reading the detailed description of non-limiting embodiments made with reference to the following drawings:

Fig. 1 is a structural schematic diagram of the present invention.

In the picture:

1 is a splitter combiner;

2 is a feeder type optical fiber;

3 is an optical amplifier;

4 is the first optical circulator;

5 is the second optical circulator.

Detailed ways

The present invention will be described in detail below in conjunction with specific embodiments. The following examples will help those skilled in the art to further understand the present invention, but do not limit the present invention in any form. It should be noted that those skilled in the art can make several modifications and improvements without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

In this embodiment, as shown in Figure 1, the TWDM-PON transmission system with load aggregation and energy-saving functions provided by the present invention includes: several subsystems and the first periodic arrayed waveguide grating; each subsystem passes through the first periodic Arrayed waveguide gratings are connected in parallel; the subsystem includes a downlink adjustable transmitter device, an uplink data processing device, a first optical circulator 4, an optical amplifier, a feeder optical fiber 2, a splitter combiner 1 and an optical network unit; Wherein, the downlink adjustable transmitter device is connected to the first end of the first optical circulator 4 through the first periodic arrayed waveguide grating; 1. The splitter combiner 1 is connected to the optical network unit; the uplink data processing device is respectively connected to the second end of the first optical circulator 4 .

The downlink adjustable transmitter device includes several downlink adjustable transmitter modules, a second periodic arrayed waveguide grating and a dispersion/chirp management unit; wherein, several downlink adjustable transmitter modules pass through the second periodic arrayed waveguide grating The input end of the dispersion/chirp management unit is connected, and the output end of the dispersion/chirp management unit is connected to the first periodic arrayed waveguide grating.

Several uplink data processing devices include several uplink data processing units, several photodetectors, a third periodic arrayed waveguide grating, and a dispersion/chirp management unit; wherein, several uplink data processing units pass through several photodetectors The output end of the third periodic arrayed waveguide grating is connected, and the second end of the first optical circulator 4 is connected to the input end of the third periodic arrayed waveguide grating through a dispersion/chirp management unit.

The optical network unit includes a second optical circulator 5, an adjustable filter, a receiver, and an uplink adjustable transmitter; the second port of the second optical circulator is connected to the splitter combiner 1 through a distributed optical fiber, and the second optical ring The third port of the optical circulator is connected to the receiver through the adjustable filter; the uplink data signal is connected to the first port of the optical circulator through the output of the uplink adjustable transmitter. The splitter combiner 1 includes an optical splitter and an optical combiner; the optical splitter is used to distribute the downlink signal to each optical network unit connected to it through the optical splitter, and the optical combiner is used to combine the uplink signal of the optical network unit for coupling. The tunable filter adopts a bandpass filter or a periodic filter.

The first periodic arrayed waveguide grating adopts N*N type periodic arrayed waveguide grating; the second periodic arrayed waveguide grating and the third periodic arrayed waveguide grating adopt 1*N type periodic arrayed waveguide grating. The first periodic arrayed waveguide grating is a second-stage periodic arrayed waveguide grating; the second periodic arrayed waveguide grating and the third periodic arrayed waveguide grating are first-stage periodic arrayed waveguide gratings.

Among them, the downlink adjustable transmitter module is connected to the first-stage periodic arrayed waveguide grating 1, the first-stage periodic arrayed waveguide grating 1 is connected to the dispersion/chirp management unit, and the dispersion/chirp management unit is connected to the second-stage Periodic arrayed waveguide grating, the second-stage periodic arrayed waveguide grating is connected to the first port of the first optical circulator, and after being output from the third port of the first optical circulator, it is connected to the optical amplifier 3 and the feeder fiber 2 in sequence. The backhaul and fronthaul are connected to the optical network unit through the splitter, and the data is sent to the receiver through the second optical circulator and adjustable filter to complete the transmission of downlink data; at the end of the optical network unit, the data from the home user Send out through the uplink adjustable transmitter, pass through the second optical circulator at the optical network unit end, connect to the feeder type optical fiber 2, the feeder type optical fiber 2 is connected to the optical amplifier 3, and the optical amplifier 3 is connected to the third port of the first optical circulator, After the output from the second port of the first optical circulator is connected to the dispersion/chirp management unit, the dispersion/chirp management unit is connected to the first-stage periodic arrayed waveguide grating 2, and is input to the uplink data processing unit through the photodetector to complete Uplink data receiving and processing; the number of downlink adjustable transmitter modules and uplink data processing units are both M, M is 2 ⁿ , and n is a natural number greater than 2. The dispersion/chirp management module means a dispersion management module or a chirp management module, and the dispersion management module is used for long-distance transmission, and the chirp management module is used for long-distance transmission with a directly modulated laser.

As shown in Figure 1, the downlink adjustable transmitter module sends a set of downlink signals, the wavelengths of which are respectively Demultiplexing is performed through the first-stage periodic arrayed waveguide grating, and then different wavelengths are distributed to different optical network units in the subsystem through the second-stage periodic arrayed waveguide grating. In the uplink direction, the uplink signal passes through the splitter combiner 1, passes through the third port of the optical circulator, and then is transmitted from the second port to the third periodic arrayed waveguide grating, and finally completes signal processing in the uplink data processing unit.

Each subsystem is equipped with an uplink adjustable transmitter. On the one hand, when the load in a certain subsystem is not aggregated, for example, when the load on a certain pair of uplink and downlink wavelengths is too large, by using some of the pair of wavelengths Data traffic is switched to other wavelength pairs with less load to achieve load aggregation in the same subsystem.

On the other hand, when the load does not converge between different subsystems, for example, the load on one subsystem is too large, while the load on another subsystem is less, and the subsystem with less load uses a pair of wavelengths at the same time. When the uplink and downlink data flow requirements can be met and the other M-1 pairs of wavelengths are in the idle state, the transmission frequency is tuned by the downlink adjustable laser module in the downlink adjustable transmitter module, so that the M-1 idle wavelengths go through a cycle after tuning The arrayed waveguide grating is distributed to the subsystem with excessive load, so that in the subsystem with excessive load, M-1 wavelengths are dynamically added on the basis of the original M wavelengths, and the capacity of the subsystem is expanded. Capacity, which enables load aggregation in different subsystems.

When the client does not have a large amount of data traffic requests, the bandwidth resources in the network are not fully utilized, and the uplink and downlink transceivers are always in operation, resulting in waste of bandwidth and unnecessary consumption of energy. After reasonable scheduling in the network, the data traffic is concentrated on certain wavelengths while the remaining wavelengths are idle, and the lasers corresponding to the remaining wavelengths are turned off. For example, in a certain subsystem, the data traffic is relatively small, and the traffic is concentrated on wavelength on while idle closure The corresponding lasers can meet the needs of users when only part of the lasers are used, thus making the entire system more energy-efficient.

When the downlink tunable transmitter module and the uplink data processing unit use directly modulated lasers, a dispersion/chirp management unit is required. If no directly modulated laser is used, the dispersion/chirp management unit may not be added.

This embodiment adopts the TWDM-PON system transmission structure with load aggregation and energy-saving functions based on periodic arrayed waveguide gratings, which has the following advantages:

1. The present invention uses a periodic arrayed waveguide grating device, which can be well compatible with the existing TWDM-PON system, and the system structure is simpler, which is conducive to smooth upgrade of the system, and can reduce the cost of PON upgrade to a certain extent;

2. The present invention performs wavelength routing through periodic arrayed waveguide gratings, and can realize load aggregation through wavelength scheduling between the same subsystem and different subsystems, providing a simple method for solving the "tidal effect";

3. When the traffic demand in the network is very small, the present invention can make the whole system more energy-saving by idle redundant wavelengths and turn off the adjustable lasers corresponding to the wavelengths under the condition of ensuring the data traffic uplink and downlink requirements.

Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art may make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention.

Claims (9)

1. A TWDM-PON transmission system having load aggregation and power saving functions, comprising: a plurality of subsystems and a first periodic array waveguide grating; the subsystems are connected in parallel through a first periodic array waveguide grating;

the subsystem comprises a downlink adjustable transmitter device, an uplink data processing device, a first optical circulator, an optical amplifier, a feed line type optical fiber, a shunt combiner and an optical network unit;

the downlink adjustable transmitter device is connected with the first end of the first optical circulator through the first periodic array waveguide grating; the third end of the first optical circulator is connected with the optical network unit sequentially through the optical amplifier, the feed line type optical fiber and the branching combiner; and the uplink data processing device is respectively connected with the second ends of the first optical circulators.

2. A TWDM-PON transmission system having load aggregation and power saving functions according to claim 1, wherein the downstream tunable transmitter apparatus comprises a plurality of downstream tunable transmitter modules, a second periodic arrayed waveguide grating, and a dispersion/chirp management unit;

the plurality of downlink tunable transmitter modules are respectively connected to the input end of the dispersion/chirp management unit through a second periodic arrayed waveguide grating, and the output end of the dispersion/chirp management unit is connected to the first periodic arrayed waveguide grating.

3. A TWDM-PON transmission system having load aggregation and energy saving functions according to claim 1 or 2, wherein the plurality of upstream data processing apparatuses include a plurality of upstream data processing units, a plurality of photodetectors, a third periodic arrayed waveguide grating, and a dispersion/chirp management unit;

the plurality of uplink data processing units are respectively connected with the output end of the third periodic array waveguide grating through a photoelectric detector, and the second end of the first optical circulator is connected with the input end of the third periodic array waveguide grating through a dispersion/chirp management unit.

4. A TWDM-PON transmission system with load aggregation and power saving functions according to claim 3, wherein the optical network unit comprises a second optical circulator, a tunable filter, a receiver and an upstream tunable transmitter;

the second port of the second optical circulator is connected with the branching combiner through a distributed optical fiber, and the third port of the second optical circulator is connected with the receiver through an adjustable filter; the upstream signal is connected to the first port of the second optical circulator through the output of the upstream tunable transmitter.

5. The TWDM-PON transmission system having a load aggregation and power saving function according to claim 1, wherein the splitting combiner comprises an optical splitter and an optical combiner; the optical splitter is used for distributing the downlink signals to each optical network unit connected with the optical splitter through the optical splitter, and the optical combiner is used for coupling the uplink signals of the optical network units.

6. A TWDM-PON transmission system having load aggregation and power saving functions according to claim 3, wherein the first periodic arrayed waveguide grating is an N x N type periodic arrayed waveguide grating; the second and third periodic arrayed waveguide gratings adopt 1 × N type periodic arrayed waveguide grating, wherein N is 2ⁿAnd n is a natural number greater than 2.

7. The TWDM-PON transmission system having load aggregation and power saving functions according to claim 2, wherein the downstream transmitter module is adjustable in block, and the tuning range is fromIs tuned intoWherein,for the mth downstream wavelength of the signal,m is 2 for the mth downstream wavelength after modulationⁿN is a natural number greater than 2, and d represents a downlink.

8. Having a negative as claimed in claim 3The TWDM-PON transmission system with aggregation and energy-saving functions is characterized in that the number of the downlink adjustable transmitter modules and the number of the uplink data processing units are M, and M is 2ⁿAnd n is a natural number greater than 2.

9. The TWDM-PON transmission system with load aggregation and power saving functions according to claim 4, wherein the tunable filter is a band-pass filter or a periodic filter.