CN201150067Y

CN201150067Y - New-style mixed type passive optical network system

Info

Publication number: CN201150067Y
Application number: CNU2007201992601U
Authority: CN
Inventors: 刘浩峰
Original assignee: Shanghai B Star Co Ltd
Current assignee: Shanghai B-Star Broadband Technology Co., Ltd.
Priority date: 2007-12-14
Filing date: 2007-12-14
Publication date: 2008-11-12
Anticipated expiration: 2017-12-14

Abstract

The utility model relates to a novel mixed type passive optical network system, which comprises a plurality of optical line terminals which all occupy two different wavelengths of the coarse wavelength division multiplexing standard, optical signal transmission respectively used for the transmitting terminal and the receiving terminal of the optical line terminals, a coarse wavelength division multiplexer and a de-multiplexer, an optical branching device provided with a plurality of ports and connected with the coarse wavelength division multiplexer and the de-multiplexer through optical fibers and a plurality of optical network units optically communicated and connected with the corresponding port of the optical branching device. The utility model adopts the mature coarse wavelength technology to ensure that a plurality of mutually separated EPON systems are simultaneously stacked to enter a single optical fiber through different CWDM optical wavelengths and simultaneously pass through the optical branching device to be shared into each ONU. The topological structure greatly saves the optical fiber resource connected between the metropolitan area network and the sub-district, simultaneously, the advantages of EPON are further taken, and the number of users can be increased flexibly, the cost of each line is reduced, and the promotion of the EPON network is accelerated.

Description

Novel hybrid passive optical network system

Technical field

The utility model relates to EPON (PON) system.

Background technology

EPON (PON) provides being connected of optical line terminal (OLT) and a plurality of optical network units (ONU), share OLT to the optical fiber medium between the distant-end node (RN), have cost low, be convenient to safeguard, to advantages such as miscellaneous service are transparent, while PON transition to optical fiber smoothly arrives family (FTTH), thereby has fine development prospect.

Ethernet passive optical network (EPON) is a power Splittable EPON, adopts star coupler along separate routes, on/descending transmission adopts time division multiple access (TDMA)/Time Division Multiplexing mode to realize the shared channel bandwidth.It is the mode that adopts luminous power to distribute, and this has limited ONU quantity, and has influenced the further network capacity extension.

1 OLT can be installed on the every optical fiber of traditional EPON system carry 32 tunnel user.Although saving that can be a large amount of than traditional transmission means fiber resource because domestic original fiber resource deficiency has still had a strong impact on the development of EPON.If lay optical fiber again, this will cause whole network cost very expensive, existing network be caused to seriously influence simultaneously.

The technical scheme that the utility model provides relates to existing Coarse Wavelength Division Multiplexing (CWDM) system, i.e. coarse wavelength division multiplexer system, and it is attached to transmit in the optical fiber by the wavelength that utilizes optical multiplexer and will transmit in different fiber and realizes.At the receiving terminal of link, utilize the wavelength after demodulation multiplexer will decompose to deliver to different optical fiber respectively, receive different receivers.The channel spacing of CWDM is 20nm, and the channel spacing of DWDM does not wait from 0.2nm to 1.2nm, so with respect to dense wave division multipurpose (DWDM) system, CWDM is called coarse wave division multiplexing technology.

The utility model content

The purpose of this utility model is, a kind of novel hybrid passive optical network system is provided.

For reaching above-mentioned purpose, the utility model adopts following technical scheme:

A kind of novel hybrid passive optical network system comprises:

A plurality of optical line terminals, each optical line terminal take two different wave lengths of Coarse Wavelength Division Multiplexing standard; Be respectively applied for the transmission of the light signal of optical line terminal transmitting terminal and receiving terminal;

Coarse Wavelength Division Multiplexing is conciliate multiplexing device, is used for the wavelength optical signals of described a plurality of optical line terminals is transmitted with on the optical fiber single;

Be provided with the optical branching device of a plurality of ports, conciliate multiplexing device with described Coarse Wavelength Division Multiplexing and be connected, be used for the luminous power on the optical fiber is assigned to each port by optical fiber;

A plurality of optical network units are connected with the optical communication of optical branching device corresponding port, and described optical network unit adopts with two identical optical wavelength of corresponding optical line terminal and transmits the uplink and downlink data respectively.

The utlity model has following advantage:

1, utilizes ripe Coarse Wavelength Division Multiplexing (CWDM) technology in simple optical fiber, to superpose the EPON system, save the optical fiber cost of metropolitan area network, enlarge whole PON network of network scope.

2, can realize that a plurality of EPON network equipments place in the same core machine room, be convenient to unified network performance maintenance and management.

3, can make EPON on original basis, increase tens of times transmission bandwidth by the Coarse Wavelength Division Multiplexing technology, insert quantity thereby increase tens of times user.

4, adopt the light signal of the intermodule OLT of CWDM to converge on the optical fiber at local side, save the line loss of light, it is irrelevant to adopt optical branching device to utilize the mode of light intensity distribution to be connected the port that makes ONU and splitter with ONU at far-end, greatly reduces the trouble of bringing in order to distinguish wavelength on practice of construction.

5,, make the direct light signal that can filter inoperative, a light signal by operation wavelength at ONU built-in optical filter plate, in actual applications, the workmen does not need to carry out the output wavelength test of each splitter, only needs directly to be connected with splitter to get final product, and has reduced mounting hardness.

6, the ONU side has adopted the Distributed Feedback Laser of CWDM standard, makes whole system be operated in 1400～1600 wave bands, can effectively avoid the 1310nm wave band in traditional cable TV, can mix with traditional cable network and use.

7, the OLT unification is positioned in the core computer lab management, and need not image intensifer.In sub-district machine room or building, passive devices such as the demodulation multiplexer of a light that the needs placement is temperature independent and optical branching device effectively increase the useful life of circuit, and have reduced the maintenance cost of network.

8, the device that uses in the utility model all can adopt ripe device, and cost is low, and the reliability height.

9, the network system that provides of the utility model when bandwidth upgrading, does not need network is carried out big transformation, reduces the upgrade of network cost.

Description of drawings

Fig. 1 is the utility model example structure schematic diagram.

Embodiment

As shown in Figure 1, a kind of novel hybrid passive optical network system comprises:

The optical line terminal of a plurality of ether optical-fiber networks (OLT) 10, promptly the OLT1 among the figure, OLT2, OLT3 ..., OLTn, each optical line terminal 10 takies two different wave lengths of Coarse Wavelength Division Multiplexing (CWDM) standard.For example, OLT1 is respectively λ 1, λ 1 ', and OLT2 is respectively λ 2, λ 2 '; OLT3 is respectively λ 3, λ 3 '; OLTn is respectively λ n, λ n '.Be respectively applied for the transmission of the light signal of OLT transmitting terminal and receiving terminal.Wherein, the transmitting terminal of OLT can adopt distributed feedback bragg grating (DFB) laser, and each OLT is arranged side by side leaves the core machine room in.

Coarse Wavelength Division Multiplexing is conciliate multiplexing device 11, be used for the different wave length of described a plurality of OLT (λ 1, λ 1 ', λ 2, λ 2 ', λ 3, λ 3 ' ..., λ n, λ n ') light signal transmitting with on the optical fiber single, to save fiber resource.

Be provided with the optical branching device 12 of a plurality of ports, conciliate multiplexing device 11 with described Coarse Wavelength Division Multiplexing and be connected, be used for the luminous power on the optical fiber is assigned to each port by optical fiber;

A plurality of optical network units (ONU) 13 are connected with described optical branching device 12 corresponding port optical communications, and ONU adopts with two identical optical wavelength of corresponding OLT and transmits the uplink and downlink data respectively.Can be equipped with corresponding ONU quantity according to corresponding OLT user's needs.For example, suppose that OLT1 need be equipped with two ONU, i.e. ONU1 and ONU1, this moment, the operation wavelength of transmitting terminal of ONU1, ONU2 was identical with the operation wavelength λ 1 of the receiving terminal of corresponding OLT; The operation wavelength of ONU receiving terminal is identical with the operation wavelength λ 1 ' of corresponding OLT transmitting terminal.

Wherein, the mode of the filter plate that the transmitting terminal of each ONU and receiving terminal can be by built-in CWDM the light signal of operation wavelength can be passed through, and the light signal of other inoperative wavelength will be isolated out.ONU can leave in the user building.

The novel hybrid passive optical network that the utility model embodiment provides adopts ripe thick wavelength-division technology that a plurality of separate EPON systems are superposeed simultaneously by different CWDM optical wavelength and enters in the simple optical fiber.Share among each ONU through optical branching device simultaneously.This topological structure is saved the fiber resource that connects between metropolitan area network and the sub-district greatly, has further brought into play the advantage of EPON simultaneously, can increase number of users neatly, has reduced the cost of every line, has quickened the popularization of EPON network.

Claims

1, a kind of novel hybrid passive optical network system is characterized in that comprising:

2, novel hybrid passive optical network system according to claim 1 is characterized in that: the transmitting terminal of described optical line terminal adopts the distributed feedback bragg grating laser.

3, novel hybrid passive optical network system according to claim 2, it is characterized in that: described optical line terminal is positioned at the core machine room.

4, novel hybrid passive optical network system according to claim 1, it is characterized in that: the transmitting terminal of described optical network unit and receiving terminal are built-in with the filter plate of CWDM.

5, novel hybrid passive optical network system according to claim 4, it is characterized in that: described optical network unit is positioned at the user building.