WO2018133503A1

WO2018133503A1 - Optical signal transmission method and system

Info

Publication number: WO2018133503A1
Application number: PCT/CN2017/109843
Authority: WO
Inventors: 冯勇华; 周伟强; 罗亚丹
Original assignee: 烽火通信科技股份有限公司
Priority date: 2017-01-22
Filing date: 2017-11-08
Publication date: 2018-07-26
Also published as: CN106899348A

Abstract

Disclosed are an optical signal transmission method and system. The system comprises an electric aggregation crossover node and an all-optical crossover node, wherein the electric aggregation crossover node encapsulates a service data into OTU2/OTU2e through aggregation or inverse multiplexing and mapping, and modulates the encapsulated data onto an optical carrier channel with a bandwidth of 2.5 GHz-12.5 GHz, or extracts the service data from optical signals on the optical carrier channel with a bandwidth of 2.5 GHz-12.5 GHz through demodulation and demultiplexing. The all-optical crossover node is provided with a narrowband wavelength selection switch matching the carrier bandwidth, and received optical signals with different wavelengths are selected and filtered using the narrowband wavelength selection switch for separation, and the optical signals of each wavelength are respectively sent to the respective electric aggregation crossover node and the all-optical crossovernode . In the present application, the contradiction between small particle services existing universally in metropolitan area networks and the requirement for a large capacity is effectively avoided, thereby reducing a network time delay and a power supply and heat dissipation requirement, and reducing the network cost.

Description

Optical signal transmission method and system

Technical field

The present invention relates to optical information transmission technologies, and in particular, to an optical signal transmission method and system.

Background technique

With the continuous advancement of the social information process, the existing optical transmission system cannot meet the increasing interconnection rate requirements, and it is urgent to further increase the transmission capacity of the optical transmission system. In fact, with the surge in network transmission capacity requirements, the single-channel transmission rate of optical transmission systems has experienced an increase from 2.5 Gbit/s to 10 Gbit/s to 40 Gbit/s to 100 Gbit/s, and is brewing under 100G. A generation of optical transmission systems.

In an optical transmission system, the transmission capacity of a single fiber depends only on the available spectrum bandwidth, modulation format, and multiplexing method, and is not necessarily related to the transmission rate of a single channel. Taking the current mainstream commercial optical transmission system based on PM-QPSK modulation, channel bandwidth 50 GHz, and single channel transmission rate 100 Gbit/s as an example, the transmission capacity of 80 waves of C-band is 8 Tbit/s; if the same modulation format and The multiplexing method increases the single-channel transmission rate to 200 Gbit/s and 400 Gbit/s respectively. At this time, the channel bandwidth is 100 GHz and 200 GHz respectively. The number of channels that can be accommodated in the C-band is reduced to 40 and 20, respectively. The capacity remains the same, still 8Tbit/s.

It can be seen that if the spectrum efficiency is not increased and the spectrum resources are increased, only increasing the single channel rate cannot increase the transmission capacity of a single fiber. In the current metropolitan area and urban and rural networks, customer service granules are mostly concentrated below 10Gbit/s. To fully utilize the channel transmission capability of 100Gbit/s and above, electrical cross-node equipment must be used for scheduling, multiplexing aggregation and demultiplexing. To resolve the contradiction between the large channel rate and the small service particles; as the electrical crossover capacity increases, not only the complexity of the device is increased, but also the operation and maintenance cost of the electrical cross-node device will increase rapidly. In the case of typical configuration, the capacity is increased. 25Tbit/s 100G electrical cross-node equipment, regardless of the matching The power consumption of the heat dissipation device will exceed 10,000 W. The power supply and heat dissipation of the large-capacity electrical cross-node device will be higher. Therefore, in solving the contradiction between the large-capacity demand of the optical transmission network and the small business particles, it is necessary to find another way.

Summary of the invention

The technical problem to be solved by the present invention is that a large-capacity electrical cross-node device is currently used to solve the contradiction between the large-capacity demand of the optical transmission network and the small service particles, and the electrical cross-node device has high complexity, operation and maintenance cost, and power consumption. The problem of increasing delays.

In order to solve the above technical problem, the technical solution adopted by the present invention is to provide an optical signal transmission system, including an electrical convergence cross node of a network edge layer and an all-optical cross node of a network core layer;

The electrical convergence cross node encapsulates the service data into OTU2 or OTU2e through aggregation or inverse multiplexing and mapping; and modulates the encapsulated data onto an optical carrier channel with a bandwidth of 2.5 GHz to 12.5 GHz; or Demultiplexing extracts service data from optical signals on an optical carrier channel having a bandwidth of 2.5 GHz to 12.5 GHz;

The all-optical cross-node is provided with a narrow-band wavelength selective switch matched with a carrier bandwidth, and the narrow-band wavelength selective switch is used to select and filter the received different wavelength optical signals, perform separation, and respectively transmit each wavelength optical signal to the corresponding electric power. Converging cross nodes or all-optical cross nodes.

In the above system, when the optical carrier signal is severely deteriorated, it is compensated and restored by electrical regeneration.

In the above system, the first all-optical cross node of the network core layer and the electrical converging cross nodes respectively connected to the first all-optical cross node in four directions; the electrical convergence cross nodes in the four directions are pressed east, The south, west and north are the east power convergence intersection node TR_E, the south electricity convergence intersection node TR_S, the west power convergence intersection node TR_W and the Nortel convergence intersection node TR_N;

The optical signal of the wavelength λ1 channel in the optical signal emitted by the west electric convergence intersection node TR_W is selected by the wavelength selection first all-optical intersection node to the Nortel convergence cross node TR_N; the wavelength λ2 pass The optical signal of the channel and the wavelength λ3 channel is selected and scheduled by the first all-optical intersection node to the east electric convergence intersection node TR_E, and the optical signal of the wavelength λ4 channel is selected and dispatched to the south electric convergence intersection node by the wavelength selection first all-optical intersection node. TR_S.

In the above system, the all-optical cross node of the network core layer includes a first all-optical cross node and a second all-optical cross node for wavelength selection;

The east side of the first all-optical cross node and the west end of the second all-optical cross node are connected to each other; the west side of the first all-optical cross node is connected to the west electric convergence cross node TR_W, and the north side is connected to the first north The electrical convergence cross node TR_N1 is connected to the first south electric convergence cross node TR_S1; the east side of the second all-optical cross node is connected to the east power convergence cross node TR_E, the north side is connected to the second Nortel convergence cross node TR_N2, and the south side is connected. The second Nandian convergence cross node TR_S2;

The optical signal of the wavelength λ1 channel in the optical signal emitted by the west electric convergence cross node TR_ is selected and dispatched to the first Nortel convergence cross node TR_N1 through the wavelength selective first all-optical cross node; the optical signal of the wavelength λ2 channel and the wavelength λ3 channel After the wavelength selection, the first all-optical cross-node selection scheduling is transmitted to the wavelength-selected second all-optical cross-node; the optical signal of the wavelength λ4 channel is selected by the first all-optical cross-node of the wavelength selection to be dispatched to the first south-electrical convergence cross node TR_S1; The optical signal of the λ2 channel is selected and dispatched to the second Nortel convergence cross node TR_N2 through the wavelength selection second all-optical cross node, and the optical signal of the wavelength λ4 channel and the west electric convergence in the optical signal emitted by the second south electric convergence intersection node TR_S2 The optical signal of the wavelength λ3 channel in the optical signal emitted by the cross node TR_W is selected and dispatched to the east power convergence cross node TR_E through the wavelength selective second all-optical cross node.

The invention also provides an optical signal transmission method, comprising the following steps:

Step S10: adopting an optical carrier channel with a bandwidth of 2.5 GHz to 12.5 GHz and a data rate of 10 Gbit/s;

Step S20: The service data is encapsulated into OTU2 or OTU2e through aggregation or inverse multiplexing, mapping, and modulated to an optical carrier channel with a bandwidth of 2.5 GHz to 12.5 GHz for transmission;

Step S30, setting an optical carrier bandwidth matching on the all-optical cross node, and having wavelength filtering selection The narrow-band wavelength selective switch of the function selects and filters the received different wavelength optical signals by using the narrow-band wavelength selective switch, performs separation, and transmits each wavelength optical signal to the corresponding cross-node, respectively, to realize cross-scheduling on different waveguide spaces.

In the above method, the bandwidth selection of the optical carrier channel depends on the planning of the spectrum usage of the network system and the modulation format adopted by the transceiver.

In the above method, the bandwidth of the optical carrier channel is typically 6.25 GHz or 12.5 GHz.

In the above method,

Using polarization-multiplexed quadrature phase-shift keying modulation or 16-level quadrature amplitude modulation, the optical signal has a baseband bandwidth of 5 GHz and is carried in a channel of 6.25 GHz bandwidth;

Polarization multiplexing 16-level quadrature amplitude modulation is adopted, and the baseband bandwidth of the optical signal is 2.5 GHz, which is carried in a channel with a bandwidth of 3.125 GHz;

With differential quadrature phase shift keying modulation, the optical signal has a baseband bandwidth of 10 GHz and is carried in a channel of 12.5 GHz bandwidth.

In the above method, the bandwidth of the optical carrier channel is compressed by using Nyquist filtering in the case where the transmission performance index permits.

The invention utilizes narrow-band all-optical transmission, and avoids the contradiction between the small-granular service and the large-capacity requirement that are common in the metropolitan area network without sacrificing the transmission capacity of the optical fiber, and does not need to adopt a complicated power-consuming electric cross-device. The granular service performs business grooming and scheduling, which reduces network delay and power supply cooling requirements, and reduces network costs.

DRAWINGS

1 is a schematic structural diagram of an optical signal transmission system according to the present invention;

2 is a schematic structural view of Embodiment 1 of the present invention;

3 is a schematic structural view of Embodiment 2 of the present invention;

FIG. 4 is a flowchart of an optical signal transmission method provided by the present invention.

detailed description

The present invention will be described in detail below with reference to the drawings and specific embodiments.

As shown in FIG. 1, an optical signal transmission system provided by the present invention is composed of an electrical convergence cross node of a network edge layer and an all-optical intersection node of a network core layer.

The electrical convergence cross-node encapsulates the service data into OTU2/OTU2e or other encapsulation format through aggregation or inverse multiplexing, mapping, and modulates the encapsulated data onto an optical carrier channel with a bandwidth of 2.5 GHz to 12.5 GHz; or, Demodulation and demultiplexing extracts traffic data from optical signals on an optical carrier channel having a bandwidth of 2.5 GHz to 12.5 GHz.

The all-optical cross-node is provided with a narrow-band wavelength selective switch matched with the carrier bandwidth, and the narrow-band wavelength selective switch is used to select and filter the received different wavelength optical signals, and separate and transmit each wavelength optical signal to the corresponding electrical convergence cross. Nodes or all-optical cross-nodes enable cross-scheduling on different waveguide spaces. In the present invention, when the optical carrier signal is severely deteriorated, the electric regeneration mode can be used for compensation and recovery.

Embodiment 1.

An optical signal transmission system as shown in FIG. 2 is connected to the first all-optical intersection node X1 for wavelength selection in the core layer and to the east, south, west, and north directions of the first all-optical intersection node X1. The four sets of edge layer electrical converging cross nodes (narrowband optical transceiver units), the four electrical convergence cross nodes are the Dongdian convergence cross node TR_E, the Nandian convergence cross node TR_S, the Xidian convergence cross node TR_W and the Nortel convergence Cross node TR_N. The service data is aggregated or inverse multiplexed, mapped, encapsulated, and modulated by edge layer electrical convergence cross nodes; or demodulated, demultiplexed, and extracted. The narrowband optical transceiver units TR_N, TR_S, TR_W and TR_E have a single wavelength optical signal bandwidth of 5 GHz and a channel rate of 10 Gbit/s.

The optical signal of the wavelength λ1 channel in the optical signal emitted by the west narrowband optical transceiver unit TR_W (including the narrowband optical transceivers TR_W1, TR_W2, ... TR_Wn) is selected by the wavelength selection first all-optical intersection node X1 to be transmitted to the north narrowband optical transceiver. The optical signals of the unit TR_N, the wavelength λ2 channel and the wavelength λ3 channel are selected and dispatched to the east narrowband optical transceiver unit through the wavelength selection first all-optical intersection node X1. TR_E, the optical signal of the wavelength λ4 channel is selected and dispatched to the south narrowband optical transceiver unit TR_S via the wavelength selective first all-optical cross node X1.

Example 2.

The core layer of an optical signal transmission system shown in FIG. 3 includes two all-optical cross nodes (X1 and X2) for wavelength selection, which are a first all-optical cross node X1 and a second all-optical cross node X2, respectively. The east end of the first all-optical cross node X1 and the west end of the second all-optical cross node X2 are connected to each other, and the first all-optical cross node X1 and the second all-optical cross node X2 are respectively connected in the other three directions. Corresponding edge layer electrical convergence cross node (narrowband optical transceiver unit), that is, the west side of the first all-optical cross node X1 is connected to the west power convergence cross node TR_W, the north side is connected to the first Nortel convergence cross node TR_N1, and the south side is connected. The first south electric convergence intersection node TR_S1, the east side of the second all-optical intersection node X2 is connected to the east power convergence intersection node TR_E, the north side is connected to the second north electricity convergence intersection node TR_N2, and the south side is connected to the second south electricity convergence intersection node TR_S2 . The service data is aggregated or inverse multiplexed, mapped, encapsulated, and modulated by edge layer electrical convergence cross nodes; or demodulated, demultiplexed, and extracted. The narrowband optical transceiver units (TR_N1, TR_N2, TR_S1, TR_S2, TR_W, and TR_E) have a single-wavelength optical signal bandwidth of 5 GHz and a channel rate of 10 Gbit/s.

The optical signal of the wavelength λ1 channel in the optical signal emitted by the west narrowband optical transceiver unit TR_W (TR_W1, TR_W2, ... TR_Wn) is selected and dispatched to the first north narrowband optical transceiver unit TR_N1 through the wavelength selective first all-optical intersection node X1. The optical signals of the wavelength λ2 channel and the wavelength λ3 channel are selected and transmitted to the wavelength selective second all-optical intersection node X2 through the wavelength selection first all-optical intersection node X1, and the optical signal of the wavelength λ4 channel is selected by the wavelength to select the first all-optical intersection node X1 The scheduling is dispatched to the first south narrowband optical transceiver unit TR_S1; the optical signal of the wavelength λ2 channel is selected and dispatched to the second north narrowband optical transceiver unit TR_N2 through the wavelength selective second all optical intersection node X2, and the second south narrowband optical transceiver unit TR_S2 is issued. The optical signal of the wavelength λ4 channel in the optical signal and the optical signal of the wavelength λ3 channel in the optical signal emitted by the west narrowband optical transceiver unit TR_W pass through the wavelength selective second all-optical intersection node X2 chooses to dispatch to the east narrowband optical transceiver unit TR_E.

As shown in FIG. 4, an optical signal transmission method provided by the present invention includes the following steps:

Step S10: adopting an optical carrier channel with a bandwidth of 2.5 GHz to 12.5 GHz and a data rate of 10 Gbit/s.

Since the optical carrier channel is narrower when the data rate of the bearer is the same, the efficiency (spectral efficiency) of the data carried by the unit bandwidth is higher. Therefore, in the case where the available spectrum bandwidth resources of the optical fiber are limited, the higher the spectral efficiency, the larger the data capacity that a single optical fiber can carry, and the lower the line cost of the data transmission per unit bit. The allowable spectral bandwidth of the optical carrier channel is largely dependent on optical device technology and process level limitations. As the optical device technology and process level increase, the minimum spectral width of the wavelength division multiplexing system has been gradually reduced from the original 100 GHz, 50 GHz. The transition to 25 GHz, 12.5 G, to the smaller 6.25 Ghz, 3.125 GHz, 2.5 GHz bandwidth, so the present invention uses a narrow-band optical carrier channel with a bandwidth of 2.5 GHz to 12.5 GHz to solve the problem that the available spectrum bandwidth of the optical fiber is limited. In addition, for the specific application scenarios of metropolitan and urban-rural networks, customer service granules are mostly concentrated at 10 Gbit/s and below, and the transmission distance is about 100 km. High-efficiency modulation formats can be adopted. The 10 Gbit/s service data particles are directly modulated into the bandwidth of 2.5 GHz to 12.5 GHz, which not only facilitates the direct scheduling of the optical switching equipment in the optical layer, but also avoids the complicated and expensive time-consuming electrical layer cross-scheduling conversion process, and improves the network link. Utilization efficiency and transmission capacity of optical fiber spectrum resources.

In the present invention, the choice of optical carrier channel bandwidth depends on the planning of the spectrum usage of the network system and the modulation format employed by the transceiver. According to the current optical device technology and process level, and fully considering the compatibility with the current optical carrier channel bandwidth (100GHz/50GHz/25GHz), the typical value (optimum value) of the optical carrier channel bandwidth is about 6.25GHz or 12.5GHz. ;E.g:

(1) Using polarization-multiplexed quadrature phase-shift keying modulation (PM-QPSK) or 16-level quadrature amplitude modulation (16QAM), the baseband bandwidth of the optical signal is about 5 GHz, which can be carried in a channel with a bandwidth of 6.25 GHz;

(2) Polarization multiplexing 16-level quadrature amplitude modulation (PM-16QAM) is adopted, and the baseband bandwidth of the optical signal is about 2.5 GHz, which can be carried in a channel with a bandwidth of 3.125 GHz;

(3) Using differential quadrature phase shift keying modulation (DQPSK), the optical signal has a baseband bandwidth of about 10 GHz and can be carried in a channel of 12.5 GHz bandwidth.

The Nyquist filter can be used to compress the bandwidth of the above optical carrier channel to improve the spectral efficiency, as the transmission performance indicator allows.

Step S20: The service data is encapsulated into OTU2 or OTU2e through aggregation or inverse multiplexing, mapping, and modulated to an optical carrier channel with a bandwidth of 2.5 GHz to 12.5 GHz for transmission.

Step S30, providing a Narrow Band Wavelength Selective Switch (NBWSS) with an optical carrier bandwidth matching function and a wavelength filter selection function at the all-optical cross node, and the all-optical cross node realizes different waveguide spaces by using a narrowband wavelength selective switch. Cross scheduling on.

It is apparent that those skilled in the art can make various modifications and variations to the invention without departing from the spirit and scope of the invention. Thus, it is intended that the present invention cover the modifications and modifications of the invention

Claims

An optical signal transmission system, comprising: an electrical convergence cross node of a network edge layer and an all-optical cross node of a network core layer;

The electrical convergence cross node encapsulates the service data into OTU2 or OTU2e through aggregation or inverse multiplexing and mapping; and modulates the encapsulated data onto an optical carrier channel with a bandwidth of 2.5 GHz to 12.5 GHz; or Demultiplexing extracts service data from optical signals on an optical carrier channel having a bandwidth of 2.5 GHz to 12.5 GHz;

The all-optical cross-node is provided with a narrow-band wavelength selective switch matched with a carrier bandwidth, and the narrow-band wavelength selective switch is used to select and filter the received different wavelength optical signals, perform separation, and respectively transmit each wavelength optical signal to the corresponding electric power. Converging cross nodes or all-optical cross nodes.
A system according to any of the preceding claims, wherein the optical carrier signal is compensated and recovered by electrical regeneration when it is severely degraded.
The system of claim 2, wherein the first all-optical cross node of the network core layer and the electrical converging cross nodes respectively connected to the first all-optical cross node are in four directions; The electrical convergence cross nodes are, in order of east, south, west and north, the east power convergence intersection node TR_E, the south power convergence intersection node TR_S, the west power convergence intersection node TR_W and the Nortel convergence intersection node TR_N;

The optical signal of the wavelength λ1 channel in the optical signal emitted by the west electric convergence cross node TR_W is selected by the first all-optical cross node of the wavelength selection to the Nortel convergence cross node TR_N; the optical signal of the wavelength λ2 channel and the wavelength λ3 channel is selected by the wavelength An all-optical cross-node is selected and dispatched to the East-East convergence cross node TR_E, and the optical signal of the wavelength λ4 channel is selected and dispatched to the Nandian convergence cross-node TR_S by the wavelength-selective first all-optical cross-node.
A system according to any of the preceding claims, wherein the all-optical cross-node of the network core layer comprises a first all-optical cross node and a second all-optical cross-node for wavelength selection;

The east side of the first all-optical cross node and the west end of the second all-optical cross node are connected to each other; the west side of the first all-optical cross node is connected to the west electric convergence cross node TR_W, and the north side is connected The first Nortel convergence cross node TR_N1, the south side is connected to the first Nandian convergence intersection node TR_S1; the second all-optical intersection node is connected to the east power convergence intersection node TR_E, and the north side is connected to the second Nortel convergence intersection node TR_N2 The south side is connected to the second south electric convergence intersection node TR_S2;

The optical signal of the wavelength λ1 channel in the optical signal emitted by the west electric convergence cross node TR_ is selected and dispatched to the first Nortel convergence cross node TR_N1 through the wavelength selective first all-optical cross node; the optical signal of the wavelength λ2 channel and the wavelength λ3 channel After the wavelength selection, the first all-optical cross-node selection scheduling is transmitted to the wavelength-selected second all-optical cross-node; the optical signal of the wavelength λ4 channel is selected by the first all-optical cross-node of the wavelength selection to be dispatched to the first south-electrical convergence cross node TR_S1; The optical signal of the λ2 channel is selected and dispatched to the second Nortel convergence cross node TR_N2 through the wavelength selection second all-optical cross node, and the optical signal of the wavelength λ4 channel and the west electric convergence in the optical signal emitted by the second south electric convergence intersection node TR_S2 The optical signal of the wavelength λ3 channel in the optical signal emitted by the cross node TR_W is selected and dispatched to the east power convergence cross node TR_E through the wavelength selective second all-optical cross node.
An optical signal transmission method, comprising the steps of:

Step S10: adopting an optical carrier channel with a bandwidth of 2.5 GHz to 12.5 GHz and a data rate of 10 Gbit/s;

Step S20: The service data is encapsulated into OTU2 or OTU2e through aggregation or inverse multiplexing, mapping, and modulated to an optical carrier channel with a bandwidth of 2.5 GHz to 12.5 GHz for transmission;

Step S30, providing a narrowband wavelength selection switch matched with an optical carrier bandwidth and having a wavelength filtering selection function on the all-optical intersection node, and performing selective filtering on the received different wavelength optical signals by using a narrowband wavelength selection switch, and separating each The wavelength optical signals are respectively sent to the corresponding cross nodes to realize cross scheduling on different waveguide spaces.
The method of claim 5 wherein the bandwidth selection of the optical carrier channel is dependent on a plan for spectrum usage of the network system and a modulation format employed by the transceiver.
The method of claim 6 wherein the bandwidth of the optical carrier channel is typically 6.25 GHz or 12.5 GHz.
The method of claim 6 wherein:

Using polarization-multiplexed quadrature phase-shift keying modulation or 16-level quadrature amplitude modulation, the optical signal has a baseband bandwidth of 5 GHz and is carried in a channel of 6.25 GHz bandwidth;

Polarization multiplexing 16-level quadrature amplitude modulation is adopted, and the baseband bandwidth of the optical signal is 2.5 GHz, which is carried in a channel with a bandwidth of 3.125 GHz;

With differential quadrature phase shift keying modulation, the optical signal has a baseband bandwidth of 10 GHz and is carried in a channel of 12.5 GHz bandwidth.
The method of claim 5 wherein the bandwidth of said optical carrier channel is compressed using Nyquist filtering if transmission performance specifications permit.