Anti-resonant hollow core fiber coherent passive optical network generation system and method

Abstract

This application discloses a system and method for generating a coherent passive optical network using anti-resonant hollow fiber, relating to the field of optical fiber communication technology. The system includes: an optical line terminal (OLT), an optical network unit (ONU), and an anti-resonant hollow fiber. The OLT is used to couple a carrier signal and a local oscillator signal to generate a downlink optical signal. The OLT transmits the downlink optical signal to the ONU via the anti-resonant hollow fiber. The ONU demodulates the downlink optical signal to obtain an uplink optical signal. The ONU transmits the uplink optical signal back to the OLT via the anti-resonant hollow fiber. Utilizing the lower transmission loss and nonlinear crosstalk characteristics of the anti-resonant hollow fiber, higher power communication transmission is achieved, improving communication capacity and bandwidth utilization efficiency. Simultaneously, the system simplifies the structural complexity of the coherent passive optical network, reduces supporting hardware resources and power consumption, and significantly lowers communication power costs.

Description

Technical Field

[0001] This application relates to the field of optical fiber communication technology, and in particular to a system and method for generating anti-resonant hollow fiber coherent passive optical networks. Background Technology

[0002] With the rapid development of information technology, fiber optic communication systems, as the infrastructure of modern communication networks, are facing increasingly higher requirements in terms of data transmission rate, transmission distance, and transmission quality.

[0003] Currently, in Coherent Passive Optical Networks (C-PON), the Optical Network Unit (ONU) accounts for approximately 75% of the total network energy consumption, and it also exhibits high structural complexity, significant hardware resource and power consumption overhead. This not only increases system cost but also limits system scalability and flexibility. Furthermore, the access network speed lags far behind the transmission rate of fiber optic channels, becoming a bottleneck for the development of ultra-high-speed communication.

[0004] Therefore, how to improve communication speed while saving resources is a problem that urgently needs to be solved. Summary of the Invention

[0005] The main objective of this application is to provide a system and method for generating anti-resonant hollow fiber coherent passive optical networks, aiming to solve the technical problem of how to save resources while improving communication speed.

[0006] To achieve the above objectives, this application proposes an anti-resonant hollow fiber coherent passive optical network generation system, the system comprising: an optical line terminal, an optical network unit, and an anti-resonant hollow fiber;

[0007] The optical line terminal is used to couple the carrier signal and the local oscillator signal to generate a downlink optical signal;

[0008] The optical line terminal is used to transmit the downlink optical signal to the optical network unit through the anti-resonant hollow optical fiber;

[0009] The optical network unit is used to demodulate the downlink optical signal to obtain the uplink optical signal;

[0010] The optical network unit is used to transmit the uplink optical signal to the optical line terminal through the anti-resonant hollow optical fiber.

[0011] In one embodiment, the optical line terminal includes: a laser, a modulation unit, a multiplexer, and a first optical amplifier;

[0012] The laser is used to generate a carrier signal and a local oscillator signal;

[0013] The modulation unit is used to modulate the carrier signal to obtain a modulated carrier signal;

[0014] The multiplexer is used to couple the modulated carrier signal and the local oscillator signal to obtain a coupled signal;

[0015] The first optical amplifier is used to amplify the coupled signal to obtain a downlink optical signal.

[0016] In one embodiment, the optical line terminal further includes: an avalanche photodiode and a first signal processor;

[0017] The avalanche photodiode is used to perform coherent detection on the uplink optical signal and the local oscillator signal, and transmit the uplink optical signal and the local oscillator signal to the first signal processor for processing.

[0018] In one embodiment, the optical network unit includes: a second optical amplifier, a demultiplexer, an integrated coherent receiver, and a second signal processor;

[0019] The second optical amplifier is used to amplify the downlink optical signal to obtain an amplified signal;

[0020] The demultiplexer is used to distribute the amplified signal to obtain a first signal and a second signal;

[0021] The integrated coherent receiver is used to perform coherent detection on the first signal and the second signal, and to transmit the first signal to the second signal processor for processing.

[0022] In one embodiment, the optical network unit further includes: a coupler and an intensity modulator;

[0023] The coupler is used to perform optical splitting on the second signal to obtain a split signal;

[0024] The intensity modulator is used to modulate the split signal to obtain an uplink optical signal.

[0025] Furthermore, to achieve the above objectives, this application also proposes a method for generating an anti-resonant hollow-core fiber coherent passive optical network. This method is applied to an anti-resonant hollow-core fiber coherent passive optical network generation system, which includes an optical line terminal, an optical network unit, and an anti-resonant hollow-core fiber. The method for generating the anti-resonant hollow-core fiber coherent passive optical network includes:

[0026] The optical line terminal couples the carrier signal and the local oscillator signal to generate a downlink optical signal;

[0027] The optical line terminal transmits the downlink optical signal to the optical network unit through the anti-resonant hollow optical fiber;

[0028] The optical network unit demodulates the downlink optical signal to obtain the uplink optical signal;

[0029] The optical network unit transmits the uplink optical signal to the optical line terminal through the anti-resonant hollow optical fiber.

[0030] In one embodiment, the optical line terminal includes: a laser, a modulation unit, a multiplexer, and a first optical amplifier;

[0031] The laser generates a carrier signal and a local oscillator signal;

[0032] The modulation unit modulates the carrier signal to obtain a modulated carrier signal;

[0033] The multiplexer couples the modulated carrier signal and the local oscillator signal to obtain a coupled signal;

[0034] The first optical amplifier amplifies the coupled signal to obtain a downlink optical signal.

[0035] In one embodiment, the optical line terminal further includes: an avalanche photodiode and a first signal processor;

[0036] The avalanche photodiode performs coherent detection on the uplink optical signal and the local oscillator signal, and transmits the uplink optical signal and the local oscillator signal to the first signal processor for processing.

[0037] In one embodiment, the optical network unit includes: a second optical amplifier, a demultiplexer, an integrated coherent receiver, and a second signal processor;

[0038] The second optical amplifier amplifies the downlink optical signal to obtain an amplified signal;

[0039] The demultiplexer distributes the amplified signal to obtain a first signal and a second signal;

[0040] The integrated coherent receiver performs coherent detection on the first signal and the second signal, and transmits the first signal to the second signal processor for processing.

[0041] In one embodiment, the optical network unit further includes: a coupler and an intensity modulator;

[0042] The coupler performs optical splitting on the second signal to obtain a split signal;

[0043] The intensity modulator modulates the split signal to obtain an uplink optical signal.

[0044] One or more technical solutions proposed in this application have at least the following technical effects:

[0045] A coherent passive optical network (PON) generation system using anti-resonant hollow fiber is provided. The system includes: an optical line terminal (OLT), an optical network unit (ONU), and an anti-resonant hollow fiber. The OLT couples a carrier signal and a local oscillator signal to generate a downlink optical signal. The OLT transmits the downlink optical signal to the ONU via the anti-resonant hollow fiber. The ONU demodulates the downlink optical signal to obtain an uplink optical signal. The ONU transmits the uplink optical signal back to the OLT via the anti-resonant hollow fiber. By using an anti-resonant hollow fiber to connect the OLT and ONU for signal transmission, the system replaces the single-mode fiber in existing standards. Utilizing the lower transmission loss and nonlinear crosstalk characteristics of the anti-resonant hollow fiber, higher power communication transmission is achieved, improving communication capacity and bandwidth utilization efficiency. Simultaneously, the anti-resonant hollow fiber has a faster propagation speed and a lower attenuation coefficient, significantly increasing network node throughput, which is beneficial for increasing the number of users and improving communication efficiency. Furthermore, the aforementioned anti-resonant hollow fiber coherent passive optical network generation system simplifies the structural complexity of coherent passive optical networks, reduces supporting hardware resources and power consumption, provides possibilities for future integration, and significantly reduces communication power costs. Attached Figure Description

[0046] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0047] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0048] Figure 1 This is a first schematic diagram of the anti-resonant hollow fiber coherent passive optical network generation system according to the first embodiment of this application;

[0049] Figure 2 This is a schematic cross-sectional view of the anti-resonant hollow fiber according to an embodiment of this application;

[0050] Figure 3 This is a second schematic diagram of the anti-resonant hollow fiber coherent passive optical network generation system in the embodiments of this application;

[0051] Figure 4 This is a signal spectrum diagram of feature point A in an embodiment of this application;

[0052] Figure 5 This is a signal spectrum diagram of feature point B in an embodiment of this application;

[0053] Figure 6 This is a signal spectrum diagram of feature point C in an embodiment of this application;

[0054] Figure 7 This is a third schematic diagram of the anti-resonant hollow fiber coherent passive optical network generation system in the embodiments of this application;

[0055] Figure 8 This is a signal spectrum diagram of feature point D in an embodiment of this application;

[0056] Figure 9 This is a signal spectrum diagram of feature point E in an embodiment of this application;

[0057] Figure 10 This is a signal spectrum diagram of feature point F in an embodiment of this application;

[0058] Figure 11 This is a schematic flowchart of the method for generating an anti-resonant hollow-core fiber coherent passive optical network according to an embodiment of this application.

[0059] Figure 12 This is a schematic diagram of the system corresponding to the method for generating an anti-resonant hollow-core fiber coherent passive optical network in the implementation method of this application.

[0060] Figure 13 This is a schematic diagram of the signal processing flow of the first signal processor in this application;

[0061] Figure 14 This is a schematic diagram of the signal processing flow of the second signal processor of this application.

[0062] Explanation of icon numbers:

[0063] 10. Optical line terminal; 101. Laser; 102. Modulation unit; 103. Multiplexer; 104. First optical amplifier; 105. Avalanche photodiode; 106. First signal processor; 20. Optical network unit; 201. Second optical amplifier; 202. Demultiplexer; 203. Integrated coherent receiver; 204. Second signal processor; 205. Coupler; 206. Intensity modulator; 30. Optical distribution network; 301. First optical circulator; 302. Anti-resonant hollow fiber; 303. Second optical circulator.

[0064] The purpose, features, and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0065] It should be understood that the specific embodiments described herein are merely illustrative of the technical solutions of this application and are not intended to limit this application.

[0066] To better understand the technical solution of this application, a detailed description will be provided below in conjunction with the accompanying drawings and specific implementation methods.

[0067] Traditional single-mode optical fibers cannot increase their transmission power indefinitely due to nonlinear crosstalk, limiting their performance in ultra-long-distance, ultra-high-speed communication applications. Especially with future demands for ultra-high capacity and ultra-high speed transmission, the performance of existing optical fiber communication systems is insufficient. Secondly, as communication networks expand, energy consumption becomes increasingly prominent, and current technologies struggle to balance increased network communication speeds with green, low-carbon energy consumption.

[0068] Furthermore, in C-PON, the optical network unit accounts for approximately 75% of the total network energy consumption, and its high structural complexity results in significant hardware resource and power consumption overhead. This not only increases system costs but also limits system scalability and flexibility. Simultaneously, the access network speed lags far behind the transmission rate of the fiber optic channel, becoming a bottleneck for the development of ultra-high-speed communication.

[0069] This application provides a system and method for generating a coherent passive optical network using anti-resonant hollow fiber. The system includes: an optical line terminal (OLT), an optical network unit (ONU), and an anti-resonant hollow fiber. The OLT is used to couple a carrier signal and a local oscillator signal to generate a downlink optical signal. The OLT transmits the downlink optical signal to the ONU via the anti-resonant hollow fiber. The ONU demodulates the downlink optical signal to obtain an uplink optical signal. The ONU transmits the uplink optical signal back to the OLT via the anti-resonant hollow fiber. Utilizing the lower transmission loss and nonlinear crosstalk characteristics of the anti-resonant hollow fiber, higher power communication transmission is achieved, improving communication capacity and bandwidth utilization efficiency. Simultaneously, the aforementioned system for generating a coherent passive optical network using anti-resonant hollow fiber simplifies the structural complexity of coherent passive optical networks, reduces supporting hardware resources and power consumption, and significantly lowers communication power costs.

[0070] Based on this, embodiments of this application provide an anti-resonant hollow-core fiber coherent passive optical network generation system, referring to... Figure 1 , Figure 1 This is an example diagram of the anti-resonant hollow fiber coherent passive optical network generation system of this application.

[0071] In this embodiment, the anti-resonant hollow fiber coherent passive optical network generation system includes: an optical line terminal 10, an optical network unit 20, and an anti-resonant hollow fiber 302; the optical line terminal 10 is used to couple a carrier signal and a local oscillator signal to generate a downlink optical signal; the optical line terminal 10 is used to transmit the downlink optical signal to the optical network unit 20 through the anti-resonant hollow fiber 302; the optical network unit 20 is used to demodulate the downlink optical signal to obtain an uplink optical signal; the optical network unit 20 is used to transmit the uplink optical signal to the optical line terminal 10 through the anti-resonant hollow fiber 302.

[0072] It should be noted that the anti-resonant hollow-core fiber 302 is a novel type of optical fiber, characterized by light propagating in air rather than within glass. This allows the optical signal transmission speed to approach the speed of light in a vacuum, while significantly reducing signal loss during transmission. The structure of the anti-resonant hollow-core fiber 302 includes a hollow core region and a multi-layer anti-resonant structure surrounding the hollow core region. This structural design allows the optical signal to be confined within the hollow core region, reducing contact with the glass material and thus lowering signal loss and nonlinear effects. For example, in bidirectional optical signal transmission, an optical circulator can be used to effectively isolate light from different directions. The anti-resonant hollow-core fiber 302 can be located in the optical distribution network unit 30, which may further include a first optical circulator 301 and a second optical circulator 303. The optical distribution network unit 30 can consist of a 20-kilometer-long hollow-core fiber, including a combination of the anti-resonant hollow-core fiber 302 and other optical fibers. The cross-section of the anti-resonant hollow-core fiber 302 is referenced. Figure 2 Downlink and uplink optical signals are transmitted bidirectionally through anti-resonant hollow fiber 302. Uplink optical signal can be understood as signal transmission from optical network unit 20 to optical line terminal 10, while downlink signal refers to signal transmission from optical line terminal 10 to optical network unit 20. Bidirectional transmission of uplink and downlink optical signals in a single fiber can be achieved using wavelength division multiplexing (WDM), including but not limited to frequency division multiplexing, code division multiplexing, orthogonal frequency division multiplexing, and time division wavelength division multiplexing.

[0073] It should be noted that the connection methods of the optical line terminal 10 and the optical network unit 20 include, but are not limited to, point-to-point, point-to-multipoint, ring, tree and other structures. The above examples are only for understanding this application and do not constitute a limitation on the connection methods of the optical line terminal 10 and the optical network unit 20 of this application.

[0074] By employing anti-resonant hollow-core fiber to connect optical line terminals and optical network units for signal transmission, this method replaces the single-mode fiber in existing standards. Leveraging the lower transmission loss and nonlinear crosstalk characteristics of anti-resonant hollow-core fiber, it enables communication transmission at higher power, improving communication capacity and bandwidth utilization efficiency. Simultaneously, anti-resonant hollow-core fiber exhibits faster propagation speed and a lower attenuation coefficient, significantly increasing network node throughput, which is beneficial for increasing the number of users and improving communication efficiency. Furthermore, the aforementioned anti-resonant hollow-core fiber coherent passive optical network generation system simplifies the structural complexity of coherent passive optical networks, reduces supporting hardware resources and power consumption, provides possibilities for future integration, and significantly reduces communication power costs.

[0075] In one implementation, reference Figure 3 The optical line terminal 10 includes a laser 101, a modulation unit 102, a multiplexer 103, and a first optical amplifier 104. The laser 101 is used to generate a carrier signal and a local oscillator signal. The modulation unit 102 is used to modulate the carrier signal to obtain a modulated carrier signal. The multiplexer 103 is used to couple the modulated carrier signal and the local oscillator signal to obtain a coupled signal. The first optical amplifier 104 is used to amplify the coupled signal to obtain a downlink optical signal.

[0076] For example, laser 101 can simultaneously serve as a downlink optical signal source and a local oscillator (LO) for the coherent detection local oscillator source at the optical network unit 20. Laser 101 generates a carrier signal with wavelength λ1, which is modulated by modulation unit 102 to obtain a modulated carrier signal. Modulation unit 102 can perform IQ quadrature modulation on the carrier signal. For example, in the anti-resonant hollow-core fiber coherent passive optical network generation system, feature point A represents the modulated signal, and the corresponding signal spectrum is shown below. Figure 4 As shown. The local oscillator at the optical line terminal 10 generates a local oscillator signal with a wavelength of λ2. For example, in the anti-resonant hollow-core fiber coherent passive optical network generation system, feature point B is taken to represent the local oscillator signal, and the corresponding signal spectrum is shown in the figure. Figure 5 As shown. Signals λ1 and λ2 arrive at multiplexer 103 for coupling. For example, in the anti-resonant hollow-core fiber coherent passive optical network generation system, feature point C represents the coupled signal, and the corresponding signal spectrum is shown below. Figure 6 As shown, the coupling signal is amplified by the first optical amplifier 104, and the output downlink optical signal is sent to the first optical circulator 301.

[0077] In this embodiment, a laser is used at the optical line terminal as both the optical signal source in the downlink direction and the coherent detection local oscillator source at the optical network unit end. This reduces the number of lasers and local oscillator signal sources at the optical network unit end, simplifying the structural complexity of coherent PON. Especially in the stage of large-scale optical line terminal deployment, it can actively respond to the environmental protection policy of reducing energy consumption and solidly promote the green, low-carbon and high-quality development of communication networks.

[0078] In one implementation, reference Figure 7 The optical network unit 20 includes a second optical amplifier 201, a demultiplexer 202, an integrated coherent receiver 203, and a second signal processor 204. The second optical amplifier 201 is used to amplify the downlink optical signal to obtain an amplified signal; the demultiplexer 202 is used to distribute the amplified signal to obtain a first signal and a second signal; the integrated coherent receiver 203 is used to perform coherent detection on the first signal and the second signal, and transmit the first signal to the second signal processor 204 for processing.

[0079] It should be noted that the optical network unit 20 further includes: a coupler 205 and an intensity modulator 206; the coupler 205 is used to split the second signal to obtain a split signal; the intensity modulator 206 is used to modulate the split signal to obtain an uplink optical signal. It should also be noted that the optical line terminal 10 further includes: an avalanche photodiode 105 and a first signal processor 106; the avalanche photodiode 105 is used to perform coherent detection on the uplink optical signal and the local oscillator signal, and transmit the uplink optical signal and the local oscillator signal to the first signal processor 106 for processing.

[0080] For example, after the downlink optical signal is sent to the first optical circulator 301, it passes through the anti-resonant hollow fiber 302 transmission link to reach the second optical circulator 303. After passing through the second optical amplifier 201, it reaches the demultiplexer 202, which splits the amplified signal into two signals (the first signal and the second signal). For example, in the anti-resonant hollow fiber coherent passive optical network generation system, feature point D represents the first signal, and the corresponding signal spectrum is shown in the figure. Figure 8 As shown. In the anti-resonant hollow-core fiber coherent passive optical network generation system, feature point E is taken to represent the second signal, and the corresponding signal spectrum is shown in the figure. Figure 9 As shown, the two signals undergo coherent detection on the integrated coherent receiver 203. The first signal is transmitted to the second signal processor 204 for processing. The second signal processor 204 can be a coherent signal processor. Simultaneously, the other signal (i.e., the second signal) is split by the coupler 205, and the split signal is input to the intensity modulator 206 for modulation. For example, in the anti-resonant hollow-core fiber coherent passive optical network generation system, feature point F represents the signal modulated by the intensity modulator 206, and the corresponding signal spectrum is shown below. Figure 10 As shown. Among them, the intensity modulator 206 can be a Mach-Zehnder modulator (MZM), which outputs an optical signal that differs from the local oscillator signal LO by several frequency differences after modulation. This signal serves as the uplink optical signal, which is then coherently detected by the avalanche photodiode 105 after passing through the first optical circulator 301 and the local oscillator signal.

[0081] In this embodiment, the transmission link uses anti-resonant hollow-core fiber to connect the optical line terminal and the optical network unit for signal transmission. This results in lower transmission loss and nonlinear crosstalk, enabling communication transmission at higher power and improving communication capacity and bandwidth utilization efficiency. Simplifying the downlink coherent transceiver reduces supporting hardware resources and power consumption, enhancing the flexibility of PON and meeting the requirements of low-cost PON applications.

[0082] Based on the above embodiments and implementation methods, referring to Figure 11 , Figure 11 This is a schematic flowchart of the method for generating an anti-resonant hollow-core fiber coherent passive optical network according to this application. The method for generating an anti-resonant hollow-core fiber coherent passive optical network according to this application is applied to the anti-resonant hollow-core fiber coherent passive optical network generation system of this application. The anti-resonant hollow-core fiber coherent passive optical network generation system includes an optical line terminal, an optical network unit, and an anti-resonant hollow-core fiber. The method for generating an anti-resonant hollow-core fiber coherent passive optical network includes steps S10 to S40:

[0083] In step S10, the optical line terminal couples the carrier signal and the local oscillator signal to generate a downlink optical signal.

[0084] It should be noted that the optical line terminal includes: a laser, a modulation unit, a multiplexer, and a first optical amplifier; the laser generates a carrier signal and a local oscillator signal; the modulation unit modulates the carrier signal to obtain a modulated carrier signal; the multiplexer couples the modulated carrier signal and the local oscillator signal to obtain a coupled signal; the first optical amplifier amplifies the coupled signal to obtain a downlink optical signal.

[0085] It should be noted that the optical line terminal also includes: an avalanche photodiode and a first signal processor; the avalanche photodiode performs coherent detection on the uplink optical signal and the local oscillator signal, and transmits the uplink optical signal and the local oscillator signal to the first signal processor for processing.

[0086] In step S20, the optical line terminal transmits the downlink optical signal to the optical network unit through an anti-resonant hollow optical fiber.

[0087] It should be noted that the anti-resonant hollow fiber can be located in the optical distribution network, and the optical distribution network unit can also include a first optical circulator and a second optical circulator. The optical distribution network unit can consist of a 20-kilometer-long hollow fiber, including a combination of the anti-resonant hollow fiber 302 and other optical fibers.

[0088] In step S30, the optical network unit demodulates the downlink optical signal to obtain the uplink optical signal.

[0089] It should be noted that the optical network unit includes: a second optical amplifier, a demultiplexer, an integrated coherent receiver, and a second signal processor; the second optical amplifier amplifies the downlink optical signal to obtain an amplified signal; the demultiplexer distributes the amplified signal to obtain a first signal and a second signal; the integrated coherent receiver performs coherent detection on the first signal and the second signal, and transmits the first signal to the second signal processor for processing.

[0090] It should be noted that the optical network unit also includes a coupler and an intensity modulator; the coupler splits the second signal to obtain a split signal; the intensity modulator modulates the split signal to obtain an uplink optical signal.

[0091] In step S40, the optical network unit transmits the uplink optical signal to the optical line terminal via an anti-resonant hollow fiber.

[0092] It should be noted that downlink and uplink optical signals are transmitted bidirectionally through anti-resonant hollow fiber. Uplink optical signal can be understood as the signal transmission from the Optical Network Unit (ONU) to the Optical Line Terminal (OLT), while downlink signal refers to the signal transmission from the OLT to the ONU. Bidirectional transmission of uplink and downlink optical signals in a single fiber can be achieved using wavelength division multiplexing (WDM), including but not limited to frequency division multiplexing, code division multiplexing, orthogonal frequency division multiplexing, and time division wavelength division multiplexing.

[0093] For example, such as Figure 12As shown, the carrier signal generated by the laser is transmitted as a wavelength λ1 modulated signal through IQ quadrature modulation. The local oscillator at the OLT end generates a wavelength λ2 local oscillator signal. The two signals are coupled to a multiplexer, amplified by a first optical amplifier, and the output downlink optical signal is sent to a first optical circulator. After passing through an anti-resonant hollow fiber transmission link, it reaches a second optical circulator. After being amplified by the second optical amplifier, it is split into two signals. The two signals are coherently detected on an integrated coherent receiver (ICR) and then sent to a signal processor (DSP) for processing. Simultaneously, one of the two signals is split and input into a Mach-Zehnder modulator for modulation, outputting an optical signal that differs from the local oscillator signal (LO) by several frequency differences. This output signal serves as the uplink signal light, which is coherently detected with the local oscillator signal at an avalanche photodiode after passing through a circulator. This reduces the number of lasers and local oscillator signal sources at the ONU end, simplifying the structural complexity of the coherent PON. The downlink optical signal power budget of the first optical amplifier is 29dB. The signal processing flow of the first signal processor can be found in [reference needed]. Figure 13 The signal processing flow of the second signal processor can be referenced. Figure 14 .

[0094] In this embodiment, anti-resonant hollow-core fiber is used to connect the optical line terminal and the optical network unit for signal transmission, replacing the single-mode fiber in the existing standard. Utilizing the lower transmission loss and nonlinear crosstalk characteristics of anti-resonant hollow-core fiber, higher power communication transmission is achieved, improving communication capacity and bandwidth utilization efficiency. Simultaneously, anti-resonant hollow-core fiber has a faster propagation speed and a lower attenuation coefficient, significantly increasing network node throughput, which is beneficial for increasing the number of users and improving communication efficiency. Furthermore, the aforementioned anti-resonant hollow-core fiber coherent passive optical network generation system simplifies the structural complexity of coherent passive optical networks, reduces supporting hardware resources and power consumption, provides possibilities for future integration, and significantly reduces communication power costs.

[0095] It should be noted that the above examples are only for understanding this application and do not constitute a limitation on the method for generating anti-resonant hollow fiber coherent passive optical networks in this application. Any simple modifications based on this technical concept are within the protection scope of this application.

[0096] The above description is only a part of the embodiments of this application and does not limit the patent scope of this application. All equivalent structural transformations made under the technical concept of this application and using the contents of the specification and drawings of this application, or direct / indirect applications in other related technical fields, are included in the patent protection scope of this application.

Claims

1. A system for generating an anti-resonant hollow-core fiber coherent passive optical network, characterized in that, The system includes: an optical line terminal, an optical network unit, and an anti-resonant hollow optical fiber; The optical line terminal is used to couple the carrier signal and the local oscillator signal to generate a downlink optical signal; The optical line terminal is used to transmit the downlink optical signal to the optical network unit through the anti-resonant hollow optical fiber; The optical network unit is used to demodulate the downlink optical signal to obtain the uplink optical signal; The optical network unit is used to transmit the uplink optical signal to the optical line terminal through the anti-resonant hollow optical fiber.

2. The system as described in claim 1, characterized in that, The optical line terminal includes: a laser, a modulation unit, a multiplexer, and a first optical amplifier; The laser is used to generate a carrier signal and a local oscillator signal; The modulation unit is used to modulate the carrier signal to obtain a modulated carrier signal; The multiplexer is used to couple the modulated carrier signal and the local oscillator signal to obtain a coupled signal; The first optical amplifier is used to amplify the coupled signal to obtain a downlink optical signal.

3. The system as described in claim 1, characterized in that, The optical line terminal also includes: an avalanche photodiode and a first signal processor; The avalanche photodiode is used to perform coherent detection on the uplink optical signal and the local oscillator signal, and transmit the uplink optical signal and the local oscillator signal to the first signal processor for processing.

4. The system as described in claim 1, characterized in that, The optical network unit includes: a second optical amplifier, a demultiplexer, an integrated coherent receiver, and a second signal processor; The second optical amplifier is used to amplify the downlink optical signal to obtain an amplified signal; The demultiplexer is used to distribute the amplified signal to obtain a first signal and a second signal; The integrated coherent receiver is used to perform coherent detection on the first signal and the second signal, and transmit the first signal to the second signal processor for processing.

5. The system as described in claim 4, characterized in that, The optical network unit further includes: a coupler and an intensity modulator; The coupler is used to perform optical splitting on the second signal to obtain a split signal; The intensity modulator is used to modulate the split signal to obtain an uplink optical signal.

6. A method for generating an anti-resonant hollow-core fiber coherent passive optical network, characterized in that, The method for generating an anti-resonant hollow-core fiber coherent passive optical network is applied to an anti-resonant hollow-core fiber coherent passive optical network generation system. The anti-resonant hollow-core fiber coherent passive optical network generation system includes an optical line terminal, an optical network unit, and an anti-resonant hollow-core fiber. The method for generating the anti-resonant hollow-core fiber coherent passive optical network includes: The optical line terminal couples the carrier signal and the local oscillator signal to generate a downlink optical signal; The optical line terminal transmits the downlink optical signal to the optical network unit through the anti-resonant hollow optical fiber; The optical network unit demodulates the downlink optical signal to obtain the uplink optical signal; The optical network unit transmits the uplink optical signal to the optical line terminal through the anti-resonant hollow optical fiber.

7. The method as described in claim 6, characterized in that, The optical line terminal includes: a laser, a modulation unit, a multiplexer, and a first optical amplifier; The laser generates a carrier signal and a local oscillator signal; The modulation unit modulates the carrier signal to obtain a modulated carrier signal; The multiplexer couples the modulated carrier signal and the local oscillator signal to obtain a coupled signal; The first optical amplifier amplifies the coupled signal to obtain a downlink optical signal.

8. The method as described in claim 6, characterized in that, The optical line terminal also includes: an avalanche photodiode and a first signal processor; The avalanche photodiode performs coherent detection on the uplink optical signal and the local oscillator signal, and transmits the uplink optical signal and the local oscillator signal to the first signal processor for processing.

9. The method as described in claim 6, characterized in that, The optical network unit includes: a second optical amplifier, a demultiplexer, an integrated coherent receiver, and a second signal processor; The second optical amplifier amplifies the downlink optical signal to obtain an amplified signal; The demultiplexer distributes the amplified signal to obtain a first signal and a second signal; The integrated coherent receiver performs coherent detection on the first signal and the second signal, and transmits the first signal to the second signal processor for processing.

10. The method as described in claim 9, characterized in that, The optical network unit further includes: a coupler and an intensity modulator; The coupler performs optical splitting on the second signal to obtain a split signal; The intensity modulator modulates the split signal to obtain an uplink optical signal.

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