WO2007143931A1

WO2007143931A1 - A wavelena wavelength division multiplexing passive optical network

Info

Publication number: WO2007143931A1
Application number: PCT/CN2007/001819
Authority: WO
Inventors: Jian Miao
Original assignee: Jian Miao
Priority date: 2006-06-09
Filing date: 2007-06-08
Publication date: 2007-12-21
Also published as: CN101087179A

Abstract

A wavelength division multiplexing passive optical fiber network system, includes: an optical fiber transmission office terminal equipment, an optical fiber feeder line and a receiving terminal, the said office terminal equipment includes a high-power single wavelength laser generating apparatus, a passive power distributor and an optical modulator, after the continuous laser outputted by the said high-power laser apparatus is divided into multiple channels by the said passive optical power distributor, one side, the said optical modulator modulates each channel of the optical signal to load the said down link packet containing the down link data, and on the other said, it provides the continuous laser as the optical source of the up link signal for the user, the each channel of the optical signal loading the down link packet and the continuous laser inputs into the optical fiber feeder line through the said WDM multiplexer. The said receiving terminal includes remote end node and multiple user end equipment, of which the remote end node includes a WDM demultiplexer for demultiplexing the down link optical signal.

Description

Wavelength division multiplexing passive optical network

The present invention relates to fiber optic communications, and more particularly to a wavelength division multiplexed passive optical network based on a high power fiber laser. Background technique

With the development of fiber-optic communication, especially Wavelength Division Mutiplexing (WDM) technology, the backbone network bandwidth for long-distance and metropolitan area communication is rapidly increasing. Inconsistent with it, it has been used to connect telecom operators for many years. The access network with the end user has been using copper technology, and has not been upgraded with the development of the backbone network. Whether it is the early 56k Modem, ISDN, or the current ADSL, VDSL technology, users have been using the telephone line to access the Internet, resulting in bandwidth limited to below 10Mbps. The application of large-bandwidth services such as video on demand and the increasing demand for access bandwidth by users have made copper technology incapable.

After 2003, with the cost reduction and the maturity of technology, the concept of FTTH: Fiber To The Home has gradually been accepted by the public. The deployment of optical access networks has become a hot topic for major operators and equipment vendors. From a technical point of view, current FTTH has two main topologies: point-to-point (single-star) structure and point-to-multipoint structure, where point-to-multipoint structure includes active double-star structure and passive double-star structure (or passive) Optical Network PON: Passive Optical Network). In the passive double-star structure, there are different multiplexing access schemes, such as: time division multiplexing access (TDMA, current standards include APON BPON, GPON, EPON, etc.); wavelength division multiplexing access (WDMA, such as WDM-PON); Subcarrier Multiple Access (SCMA) and hybrid access in multiple modes (eg WDM+SCMA, WDM+TDMA). The technical standards of APON/BPON, GPON and EPON have been formulated by TU-T, IEEE and other institutions.

As shown in Figure 1, the basic structure of the PON is: one end of the fiber is connected to the central office (CO: Central Office), and the other end is connected to multiple users through a passive optical splitter (POS: Passive Optical Splitter). N user access is also provided. The single-star structure requires N fiber feeders and 2N transceivers. The active double-star structure requires 1 fiber feeder and 2N+2 transceivers. The PON requires only 1 fiber feeder, N+. 1 transceiver. PON requires the least amount of fiber and transceiver, and the lowest cost, so it is undoubtedly appropriate to promote FTTH construction at this stage.

FIG. 2 is a schematic diagram of a triple play FTTH solution using GPON (Gigabit-capable PON) or EPON (Ethernet PON) technology. The system consists of the optical line terminal (OLT: Optical Line Terminal), the optical fiber feeder, the passive optical splitter POS, and the optical equipment unit of the customer premises equipment (ONU: Optical Network Unit). At the central office, the OLT uniformly packs the downlink audio, video, and other data into Ethernet data frames and sends them to the client in the form of optical signals. The client ONU accepts Ethernet data frames, and processes the data and transmits it to the corresponding terminal, such as a telephone, a television, or a computer. On the uplink, the ONU packs the audio, video, and data into Ethernet data frames and sends them to the OLT as optical signals.

The main problem with GPON/EPON is that since multiple users share a transceiver at the central office, the bandwidth that each user can actually allocate is much smaller than the bandwidth of the transceiver. Taking 32 EPON access as an example, each user is equipped with a transceiver with a bandwidth of 1.25 Gbps, but the average bandwidth after sharing is only about 30 Mbps. Although 30Mbps has greatly exceeded the bandwidth of current copper access, in the future, in the context of triple play, with the popularity of broadband applications such as HDTV, it is expected that 30Mbps bandwidth will become a new access bottleneck by 2010.

To break through this bottleneck, it must be a transceiver for each user's exclusive central office. In the case that PON has been established in a large number, the simplest upgrade solution is to deploy WDM-PON.

The principle of WDM-PON is shown in Figure 3. The system uses 2N wavelengths to provide access services for N users. Each user uses one wavelength for uplink and downlink, where wavelengths are 1⁄2 ₊₁ and λ _Ν+2 . .λ _{2Ν is} used for data downlink, and enters the downlink fiber through the central-end WDM multiplexing device, and is allocated to different users after the remote node RN close to the user is demultiplexed; ₂ .. ₁ ^ is used for data uplink, The remote node is multiplexed into the upstream fiber and received by the receiver after the central office is demultiplexed. Among them, DFB lasers are used as WDM light sources for high-rate data transmission; at low rates, low-cost spectrum-slicing schemes can be considered; each user is equipped with LEDs of the same spectral structure, The wide spectral signal is filtered out of different wavelengths by wavelength division multiplexing/demultiplexing for uplink/downlink data transmission.

The low cost advantage of the spectral segmentation scheme comes from two aspects. One is the low cost of the device, the price of the LED is much lower than the DFB or DBR laser commonly used in WDM systems; the other is that the user can be equipped with the same LED without different wavelengths. The cost of lasers, laying and operation and maintenance is drastically reduced. However, the shortcomings of the spectral segmentation scheme are also obvious: the LED itself has a small luminous power (about -10 dBm), and the spectral segmentation causes a large power loss, resulting in a low received optical power and an increased system error rate. Only by reducing the data transmission rate can the system maintain a low bit error rate. Therefore, the LED spectrum division scheme can only be applied to low-rate access. To overcome this shortcoming, the researchers used Super luminescent Diodes (SLD) combined with Erbium-Doped Fiber Amplifier (EDFA), Amplified Spontaneous Emission (ASE) source, and spectral broadening. The Fabry-Perot laser (FP-LD) replaces the LED for spectral segmentation, which gives the system some improvement, but for high-rate applications, the effect is still not ideal (SL Woodward et αί, "A spectrally Sliced PON employing Fabry-Perot lasers, "IEEE Photon. Technol. Lett, vol. 10, pp. 1337-1339, Sep. 1998). Another technical solution to reduce the cost of WDM access networks is the Loop-Back technology. Kobrinsky et al. (H. Kobrinski et al, "Laser power sharing in the subscriber loop," Electron. Lett, vol. 23, pp. 943-944, 1987 and: NJ Frigo et al, "A wavelength-division multiplexing passive optical Network with cost-shared components," IEEE Photon. Technol. Lett, vol.6, pp.1365-1367, Nov. 1994) proposes that it is not necessary to equip the user with a high-cost laser, and only a part of the downstream light needs to be used in the semiconductor. After the LiNbO ₃ modulator is modulated and sent back to the upstream fiber, the uplink data can be transmitted. The principle is shown in Figure 4. The downlink data packet is divided into two segments according to time. The previous segment is a modulated signal for transmitting downlink data. The latter segment is unmodulated continuous light, which is modulated by the user terminal (ONU). Loopback, used to transmit upstream data. This solution simplifies the customer-side laser, but the central office needs to be equipped with a high-cost DFB or DBR laser, which hinders further cost reduction.

Recently, a low-cost WDM-PON scheme based on ASE-injected Fabry-Perot Laser Diode has attracted widespread attention. In general, the FP-LD produces a laser output that contains multiple longitudinal modes (multiple wavelengths) and is not suitable for WDM applications. Chang-Hee Lee et al. used the injection mode locking principle of FP-LD to generate broadband incoherent light by self-radiation of erbium-doped fiber, and obtained a narrow-band source by spectral splitting, which was injected into FP-LD, forcing FP-LD to produce single longitudinal The laser output of the mode is successfully applied to WDM-PON with a wavelength of 32 km and an access distance of 20 km. Their experimental system is shown in Figure 5. The broadband broadband source (BLS: Broad-band Light Source) provides broadband incoherent light, which is sent to the downstream fiber through the circulator, injected into the FP-LD, forcing the FP-LD to produce a single longitudinal mode. Laser output. The FP-LD is directly modulated, and the signal light is multiplexed by the AWG wavelength and sent to the optical fiber for uplink. After the central circulator, the receiver RX reads the data.

The advantages of the above solution are low cost, the related technologies are mature, and all the users are equipped with the same FP-LD, and the system is easy to maintain and easy to implement. However, since 2000, the access rate of its test system has been staying at around 100 Mbps. For higher speed applications (for example, lGbps), it is still necessary to conduct in-depth research.

Another area of optoelectronics, namely high-power fiber lasers, has achieved fruitful results after more than 30 years of development. Currently, its main applications are in laser processing and marking. Now Er-Yb co-doped fiber lasers have been able to provide stable laser output in the 1550 nm wavelength region (the operating wavelength of dense wavelength division multiplexed fiber optic communication systems). The following literature reports recent recent developments in this field: Fiber lasers using a distributed Bragg reflector (DBR: Distributed Bragg Reflector) can produce a power output of 20 mW with a linewidth narrower than 2 kHz (Ch. Spiegelberg et al., Low-noise narrow-linewidth fiber laser at 1550nm (June 2003)," J. Lightwave Technol, vol. 22, pp. 57-62, 2004); using large-core 铒-镱惨惨光纤 fiber laser (large-core Er -Yb Co-doped fiber laser) and tunable narrow-band fiber Bragg grating (FBG: Fiber Bragg), which produces a wavelength-adjustable laser output between 1532 nm and 1567 nm with a power of 40 W and a linewidth of 0.16 nm (Y. Jeong et al. , "A 43-W C-Band tunable narrow-linewidth erbium/ytterbium co-doped large-core fiber laser," IEEE Photon. Technol. Lett, vol. 16, pp.756-8, 2004); as a broadband Light source, Er-Yb co-doped fiber laser can even produce more than 1000W output power around 1565nm (JK Sahu et al, "A 103W erbium/ytterbium co-doped large-core fiber laser," Opt. Commun., vol. 227 , pp.159-63, 2003).

In fiber-optic communications, optical modulators are also an important component because continuous lasers must be modulated to load data. Currently used optical modulators generally use III-V semiconductor or lithium niobate (LiNbO ₃ ) materials, which are expensive and suitable for long-distance high-rate optical communication, and are not suitable for low-cost access network applications. Recently, Intel Corporation has made breakthroughs in the research of optical modulation devices (A. Liu et al, "A high-speed silicon optical modulator based on a metal-oxide-semi-conductor capacitor," Nature, vol.427, pp .615-618, Feb.12, 2004, and Intel Technology Journal, vol. 8, issue 2, pp. 143-158, May 10, 2004), developed a 2.5 GHz bandwidth, working on silicon-based light modulation around 1550 nm Device. This means that optical modulation devices can be produced using mature silicon-based integrated circuit processes, which will inevitably reduce costs and obtain applications in the field of optical access networks. Summary of the invention

It is an object of the present invention to provide a novel wavelength division multiplexed passive optical network scheme based on a high power fiber laser.

The wavelength division multiplexing passive optical network system of the present invention comprises:

a fiber optic transmission central office device, the device outputs a downlink optical signal loaded with a downlink data packet through a WDM multiplexer;

An optical fiber feeder, configured to transmit the downlink optical signal loaded with the downlink data packet and a continuous laser, which may also be used to transmit an uplink optical signal loaded with an uplink data packet;

The receiving end includes a remote node and a plurality of user equipments, where the remote node includes a WDM demultiplexer for demultiplexing the downlink optical signal, and the user equipment obtains the downlink after the demultiplexing And modulating the continuous laser to generate an upstream optical signal loaded with an uplink data packet, and transmitting the optical signal to the central office equipment through an optical fiber feeder.

The central office device further includes a high power fiber laser generating device, a passive optical power splitter, and a light modulator, wherein the continuous laser outputted by the high power laser is divided into multiple paths by the passive optical power splitter, Modulating each successive laser by the optical modulator for loading the lower portion containing the downlink data The line data packet, on the other hand, provides the user with a continuous laser as the light source of the uplink signal, and each of the optical signals after the loading of the downlink data packet and the continuous laser light are transmitted into the optical fiber feeder through the TOM multiplexer.

As a special implementation, the present invention further provides a single wavelength point-to-point fiber access network system, the access network system comprising:

The optical fiber transmission central end device includes a high power fiber laser and a passive optical power splitter and a modulator working therewith, wherein the continuous laser outputted by the high power laser is divided into multiple paths by the passive optical power splitter, and Modulating each continuous laser by the modulator for loading a downlink data packet;

a plurality of optical fiber feeders for transmitting a downlink optical signal loaded with a downlink data packet, a continuous laser light as a user terminal light source, and an uplink optical signal loaded with an uplink data packet;

A client device, where each client end corresponds to a group of the fiber feeders for acquiring downlink data packets. The client also includes a modulator for modulating the continuous laser and loading the upstream packets.

The wavelength division multiplexing optical fiber network of the present invention has a simple principle and is convenient to implement. By sharing a fiber laser with multiple users, the cost of the light source can be greatly reduced, the bandwidth can reach 1 Gbps, and it is easy to upgrade to a higher rate. DRAWINGS

1 is a schematic diagram of the basic structure of a passive optical network;

2 is a schematic diagram of a triple play solution using GPON or EPON technology;

Figure 3 is a schematic diagram of the principle of WDM-PON;

4 is a schematic diagram of a WDM access network using optical loopback technology;

5 is a schematic diagram of a WDM-PON in which an FP laser is injected using spontaneous emission;

Figure 6 is a schematic view of an embodiment of the present invention;

Figure 7 is a schematic view of another embodiment of the present invention;

Figure 8 is a schematic view of still another embodiment of the present invention;

Figure 9 is a schematic illustration of still another embodiment of the present invention. detailed description

FIG. 6 is a schematic diagram of a wavelength division multiplexing passive optical network according to the present invention. The solution includes a central office device 100, a receiving end 200, and an optical fiber feeder 1 connected to the central office and the receiving end. The central office device 100 a high-power single-wavelength fiber laser array 110 comprising N high-power single-wavelength fiber lasers, and a multi-stage passive optical power splitter 120, a modulator array 130, and a wavelength division multiplexer 140 matched thereto; 100 also includes a receiver array 150 and a wave decomposition multiplexer 160 that cooperates therewith. The receiving end 200 includes a remote node 210 and a client device 220, and the remote node 210 includes a wavelength division multiplexer 211 and a wave. The demultiplexer 212, the client device 220 includes a receiver 221 and a matching optical splitter 222 and a circulator 223. The client device 220 further includes a modulator 224.

N high-power single-wavelength fiber lasers 110 respectively output different single-wavelength continuous lasers (λ _ΐ5 λ ₂ ... λ _Ν ), and each laser is divided into multiple paths by multi-stage passive optical power splitter 120, and modulated by The processor 130 modulates each successive laser to load the downlink data; after the modulation, the downlink data packet is composed of two parts, the first half is the downlink data, and the second half is the continuous "1" (ie, the continuous light wave). The multi-path downstream optical signals of different wavelengths are passed through a wavelength division multiplexer (WDM MUX) 140 and a circulator 170 and then merged into a fiber feeder 1 for downlink. At the receiving end 200, a remote demultiplexer (WDM DEMUX) 212 of the remote node 210 demultiplexes the downstream signals and assigns different wavelengths to different users. Through the circulator 223 and the optical splitter 222 provided by the user terminal 220, part of the downlink optical power is received by the receiver 221 to acquire downlink data; and another part of the downlink optical power is sent to the modulator 224, and the modulator 224 pairs the downlink data packet. The continuous light wave in the medium is modulated, and after loading the data, it goes up through the circulator 223. At this time, the first half of the upstream packet includes the original downlink data, and the second half is modulated as the uplink data. The uplink data packets from different users (i.e., different wavelengths) are multiplexed by the wavelength division multiplexer 211 and then transmitted through the optical fiber feeder 1 for uplink transmission, and then passed through the circulator 170 of the central office device 100 and then solved by the WDM demultiplexer 160. The multiplex is received and received by a corresponding receiver in the receiver array 150 to obtain uplink data.

Figure 7 is a schematic view of another embodiment of the present invention. The difference from the previous embodiment is that the uplink and downlink optical signals in the network are transmitted through the two optical fibers 2, 3, respectively. Specifically, the solution of this embodiment includes a central office device 300 and a receiving end 400. The central office device 300 includes two high-power single-wavelength fiber lasers 310 and a multi-stage passive optical power splitter 320 for use therewith. The modulator array 330 and the wavelength division multiplexer 340, the central office device 300 also includes a receiver array 350 and a wave decomposition multiplexer 360 that cooperates therewith. The receiving end 400 also includes a remote node 410 and a client device 420. The remote node 410 includes a wavelength division multiplexer 411 and a wave decomposition multiplexer 412. The client device 420 includes a receiver 421 and a modulator 422.

The continuous laser outputted by the two high-power single-wavelength fiber lasers 310 (λ _ΐ5 λ ₂ ... λ ₂ _Ν ) is divided into multiple paths by the passive optical power splitter 320 to allocate two wavelengths λ to each user. _{Πλ Ν+ί} (i=l,2...N) laser. The modulator 330 is modulated to load the downlink data, and λ _Ν+ί provides the user with continuous light waves. λ _ΐ5 λ ₂ ... λ ₂ _进入 enters the downstream fiber 2 through the wavelength division multiplexer 340, and is received by the receiver 421 provided by the client device 420 after the remote node 410 is demultiplexed by the wave decomposition multiplexer 412. Thus reading the downlink data; continuous light waves! ^ is then modulated by user modulator 422 to load upstream data. Upstream optical signals _{_{λ Ν + 1, λ Ν +}} 2 ... λ 3 after _2Ν multiplexed uplink transmission via fiber, the central office 360 is a wavelength division demultiplexing multiplexed Solutions 300 received by a receiver array 350. FIG. 8 shows another embodiment of the light source portion of the central office device 500 of the present invention, which uses the multi-wavelength fiber laser 510 and the WDM demultiplexing device 520 to replace the single-wavelength fiber laser array in the above two embodiments. , which can further reduce the number of active devices and reduce costs.

As shown in FIG. 9, a special embodiment of the present invention is a single-wavelength point-to-point solution, which is suitable for point-to-point optical fiber transmission of data, voice, video, and the like. Embodiments in this embodiment include a central office device 600, a receiving end 700, and multiple optical fibers. The central office device 600 includes a high-power laser 610 and a multi-stage passive optical power splitter 620, a modulator 630, and the central office device further includes a plurality of receivers 640. The receiving end 700 includes a receiver 710 and a splitter. The 720 and the modulator 730.

The continuous laser output from the high-power fiber laser 610 equipped with the central office equipment 600 is divided into multiple paths by the passive optical power splitter 620, and each continuous laser is modulated by the modulator 630, similar to the first embodiment, the modulated data. The package consists of two parts, the first half is the downlink data, and the second half is the continuous "1" (ie continuous light wave). Each optical signal is transmitted directly to the receiving end through a downlink point-to-point fiber link. Through the beam splitter 720, part of the optical power is received by the receiver 710 to acquire downlink data; part of the optical power is sent to the modulator 730. Modulator 730 modulates the continuous optical waves in the downstream optical signal, loads the data, and sends it back to the upstream optical fiber. At this time, the first half of the uplink packet retains the original downlink data, and the latter half is modulated into the uplink data, and the point-to-point fiber link is sent to the central office device 600 and received by the corresponding receiver 640 to acquire the uplink data.

In the present invention, a tunable fiber laser can be used instead of a single-wavelength fiber laser array or a multi-wavelength fiber laser, and different types of optical power distribution devices, optical modulator devices, wavelength division multiplexing/demultiplexing devices, and optical rings can be selected. For example, a technician familiar with fiber-optic communication can also construct more embodiments (such as a ring topology, etc.) by changing the network structure.

The wavelength division multiplexing optical fiber network of the invention has the advantages of simple principle, convenient implementation and the following advantages:

1. By sharing the fiber laser with multiple users, the cost of the light source can be greatly reduced;

2. The fiber laser is mature now. Its resonant cavity is short, the structure is simple and compact, and it can be easily integrated into the OLT. It has high power output, low noise, stable operation and long life. It is suitable for carrier-grade applications.

3. All users are equipped with the same ONU. The receiver and modulator are independent of wavelength, which can simplify the operation and maintenance of the system and reduce the management cost.

4. Easy to upgrade, the bandwidth depends only on the bandwidth of the modulator. Currently, the modulator can have a bandwidth of 1 Gbps, and can be upgraded to a higher rate if needed and cost-effective.

Claims

Claim

1. A wavelength division multiplexing passive optical network system, comprising:

a fiber optic transmission central office device, the central office device outputs a downlink optical signal loaded with a downlink data packet through a WDM multiplexer;

An optical fiber feeder, configured to transmit the downlink optical signal loaded with the downlink data packet, and to transmit an uplink optical signal loaded with an uplink data packet;

The receiving end includes a remote node and a plurality of client devices, wherein the remote node includes a WDM demultiplexer for demultiplexing the downlink optical signal, and the user equipment acquires the downlink after the demultiplexing An optical signal, and modulating the upstream optical signal, and transmitting the optical signal to the central office through a fiber feeder; wherein the central office further includes a high power laser generating device, a passive optical power splitter, and a light modulator. After the continuous laser output from the high-power laser device is divided into multiple paths by the passive optical power splitter, each optical signal is modulated by the optical modulator to load the downlink including the downlink data. The data packet, on the other hand, provides the user with a continuous laser as the light source of the uplink signal, and each optical signal after loading the downlink data packet and the continuous laser light are transmitted into the optical fiber feeder through the WDM multiplexer.

2. The wavelength division multiplexing passive optical network system according to claim 1, wherein the user end comprises a circulator, a beam splitter and a receiver, and the downlink optical power is partially passed by the circulator and the optical splitter. The receiver receives to obtain the downlink data.

The wavelength division multiplexing passive optical fiber network system according to any one of claims 1 to 2, wherein the high power laser generating device is a high power single wavelength fiber laser, and the output optical signal is Single wavelength continuous laser.

The wavelength division multiplexing passive optical fiber network system according to any one of claims 1 to 2, wherein the high power laser generating device comprises a multi-wavelength high power fiber laser and a WDM working therewith Demultiplexer.

The wavelength division multiplexing passive optical network system according to any one of claims 1 to 4, wherein the uplink and downlink optical signals are transmitted through the same optical fiber feeder.

The wavelength division multiplexing passive optical fiber network system according to claim 5, wherein each of the downlink optical signals comprises a laser signal of one wavelength, and the downlink data packet loaded includes two parts, wherein the first half For the downlink data, the latter half is a continuous light wave.

The wavelength division multiplexing passive optical network system according to claim 6, wherein the user end further comprises a modulator, the modulator modulates and loads the continuous optical wave in the downlink data packet. The uplink data packet after the data is uplinked by the circulator, the first half of the uplink data packet includes the downlink data, and the second half is the uplink data.

The wavelength division multiplexing passive optical fiber network system according to any one of claims 1 to 4, wherein the downlink optical signal and the uplink optical signal are transmitted through a downlink optical fiber feeder and an uplink optical fiber feeder, respectively.

9. The wavelength division multiplexing passive optical network system according to claim 8, wherein each of the downstream optical signals comprises two wavelengths of laser signals, one of which is used to load downlink data, and the other wavelength is used. Used to provide continuous light waves to users.

The wavelength division multiplexing passive optical fiber network system according to claim 9, wherein the user end further comprises a modulator, the modulator modulates the continuous optical wave, and uplink data after loading data The packet goes up through the circulator.

A single-wavelength point-to-point optical fiber network system, the network system comprising: a fiber transmission central office device, comprising a high-power fiber laser and a passive power splitter and a modulator working therewith, the high-power laser The output continuous laser is divided into multiple paths by the passive optical power splitter, and each continuous laser is modulated by the modulator for loading downlink data packets;

a plurality of optical fiber feeders for transmitting a downlink optical signal loaded with a downlink data packet, and for transmitting an uplink optical signal loaded with an uplink data packet;

A client device, where each client end corresponds to a group of the fiber feeders for acquiring downlink data packets.

12. The single wavelength point-to-point fiber optic network system of claim 11 wherein each of said sets of optical fiber feeders comprises an upstream fiber feed line and a downstream fiber feed line.

The single-wavelength point-to-point optical fiber network system according to any one of claims 11 or 12, wherein the downlink data packet comprises two parts, wherein the first half is downlink data and the second half is continuous lightwave.

The single-wavelength point-to-point optical fiber network system according to claim 13, wherein the user end further comprises a modulator, the modulator modulates continuous optical waves in the downlink data packet, and after loading data The uplink data packet is uplinked through an uplink optical fiber feeder corresponding to the user end, and the first half of the uplink data packet includes the downlink data, and the second half of the uplink data is uplink data.