Passive optical network system based on hollow-core optical fiber energization and use method

Abstract

The invention relates to a passive optical network system based on hollow-core optical fiber energization, and the system comprises a transmitting unit which is used for generating and outputting communication signal light of a passive optical network and energy light for power supply; the input end of the wavelength division multiplexing unit is connected with the light emitting unit, and the wavelength division multiplexing unit is used for combining the communication signal light and the energy light into a beam of composite light; the input end of the hollow-core optical fiber is connected with the output end of the wavelength division multiplexing unit through a first connecting unit, and the hollow-core optical fiber is used for transmitting the composite light; and the input end of the wavelength division demultiplexing unit is connected with the output end of the hollow-core optical fiber through a second connecting unit. The hollow-core optical fiber is adopted as a transmission medium, the nonlinear effect generated by a traditional solid-core optical fiber in high-power laser transmission is effectively restrained, signal light quality degradation is avoided, high-power energy light transmission is achieved under the condition that signal quality is not affected, the maintenance cost of the system can be reduced, and the stability of the system can be improved.

Description

Technical Field

[0001] This invention relates to the field of optical communication technology, specifically to a passive optical network system based on hollow-core optical fiber and its usage method. Background Technology

[0002] Passive optical networks (PONs) have become the mainstream technology for fiber optic access networks due to their advantages such as high bandwidth, low cost, and easy expansion. In traditional PON systems, although the optical distribution network (ODN) is a passive structure, the optical network terminals (ONTs) located on the user side, as well as the active units in the optical amplifiers (OAs) and remote nodes (RNs) that may be deployed in the system, still require external power supply to work properly. Providing a stable and reliable power supply for these devices in remote areas, outdoor environments, special industrial scenarios, or areas where it is difficult to lay power lines has become a prominent engineering challenge.

[0003] To address the aforementioned issues, fiber-optic power supply technology has emerged. This technology transmits high-power laser light through optical fibers and converts the light energy into electrical energy at a remote location using a photovoltaic converter, thereby powering optical network equipment. Currently, the photoelectric conversion efficiency of commercial photovoltaic converters has exceeded 40%, providing a certain foundation for practical application. However, traditional fiber-optic power supply technology typically uses solid-core optical fibers as the power transmission medium. When transmitting high-power laser light, solid-core optical fibers are susceptible to nonlinear effects (such as stimulated Raman scattering and stimulated Brillouin scattering), which not only limits the upper limit of transmission power but may also interfere with communication signals transmitted in the same fiber core, leading to signal quality degradation. Furthermore, prolonged transmission of high-power laser light in solid-core optical fibers may cause fiber damage, reducing system reliability. Therefore, there is an urgent need to propose a novel passive optical network architecture and implementation method to overcome the limitations of traditional fiber-optic power supply technology in terms of power, signal quality, and transmission distance. Summary of the Invention

[0004] This application provides a passive optical network system and its usage method based on hollow-core optical fiber to solve the above problems.

[0005] In a first aspect, embodiments of this application provide a passive optical network system based on hollow-core optical fiber, comprising: The transmitting unit is used to generate and output communication signal light and power energy light for the passive optical network. A wavelength division multiplexing unit, whose input is connected to the optical emitting unit, is used to combine communication signal light and energy light into a composite light beam. A hollow-core optical fiber, the input end of which is connected to the output end of the wavelength division multiplexing unit through a first connection unit, is used for transmitting the composite light; The wave demultiplexing unit has its input end connected to the output end of the hollow optical fiber through a second connection unit, and is used to separate the transmitted composite light wave into communication signal light and high-power energy light. The receiving unit is connected to the output of the wave demultiplexing unit. It is used to receive the separated communication signal light and energy light, convert the energy light into electrical energy to power the remote equipment of the passive optical network system, and transmit the communication signal light to the user-side optical network terminal.

[0006] In conjunction with the first aspect, in one embodiment, the hollow optical fiber is an anti-resonant hollow optical fiber.

[0007] In conjunction with the first aspect, in one embodiment, the first connecting unit and the second connecting unit are solid optical fibers.

[0008] In conjunction with the first aspect, in one embodiment, the solid-core optical fiber is a first single-mode optical fiber whose mode field diameter matches that of the hollow-core optical fiber. The first single-mode optical fiber is fused to the wavelength division multiplexing unit and the wavelength division demultiplexing unit, and the mode fields at the connection ends are matched. The first single-mode optical fiber and the hollow-core optical fiber are connected by bevel fusion splicing.

[0009] In conjunction with the first aspect, in one embodiment, the solid-core optical fiber is a second single-mode optical fiber whose mode field diameter does not match that of the hollow-core optical fiber. The second single-mode optical fiber is fused to the wavelength division multiplexing unit and the wavelength division demultiplexing unit, and the second single-mode optical fiber and the hollow-core optical fiber are optically coupled together through a lens unit.

[0010] In conjunction with the first aspect, in one embodiment, the lens unit includes an independent lens disposed between the second single-mode fiber and the hollow fiber, or an integrated lens formed at the end of the second single-mode fiber.

[0011] In conjunction with the first aspect, in one embodiment, the integrated lens is a spherical lens.

[0012] In conjunction with the first aspect, in one embodiment, the transmitting unit includes: The signal transmitting module is used to generate and output communication signal light; Energy emission module, used to generate and output energy light.

[0013] In conjunction with the first aspect, in one embodiment, the receiving unit includes: The signal receiving module is used to transmit communication signal optically to the user-side optical network terminal; Energy conversion module, which is used to convert light energy into electrical energy.

[0014] Secondly, embodiments of this application provide a method for using a passive optical network system powered by hollow-core optical fiber, comprising the following steps: The transmitting unit generates and outputs communication signal light and energy light for power supply of the passive optical network. The communication signal light and the energy light are combined into a composite light beam by a wavelength division multiplexing unit. The composite light is coupled into a hollow optical fiber for transmission through the first connection unit; The transmitted composite light is coupled from the hollow fiber to the wave decomposition and multiplexing unit through the second connection unit; The composite optical wave decomposition and multiplexing unit separates the composite optical wave into communication signal light and energy light. The receiving unit receives the separated communication signal light and energy light, converts the energy light into electrical energy to power the remote equipment of the passive optical network system, and transmits the communication signal light to the user-side optical network terminal.

[0015] The beneficial effects of the technical solutions provided in this application include: 1. This application effectively suppresses the nonlinear effects generated by traditional solid optical fibers in high-power laser transmission by using hollow optical fibers as the transmission medium, avoids signal light quality degradation, and achieves high-power energy light transmission without affecting signal quality. This can reduce system maintenance costs, improve system stability, and provide a good solution for the problem of unstable power supply in remote areas and complex wiring environments.

[0016] 2. This application enables the simultaneous transmission of communication signals and electrical energy through a single hollow optical fiber, reducing the need for additional power cables, lowering the complexity of network deployment and long-term maintenance costs, and facilitating the widespread application of passive optical networks in areas without mains power. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a simplified connection diagram of the system of the present invention; Figure 2 This is a detailed schematic diagram of the system of the present invention; Figure 3 This is a diagram illustrating the steps of the method in Embodiment 3 of the present invention. Detailed Implementation

[0019] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present application.

[0020] Example 1: Please see Figure 1 and Figure 2 Embodiment 1 of this application provides a passive optical network system based on hollow-core optical fiber, comprising: The transmitting unit is used to generate and output communication signal light and power energy light for the passive optical network. The transmitting unit includes a signal transmitting module and an energy transmitting module. The signal transmitting module is usually an optical line terminal conforming to the PON standard, used to generate and output communication signal light for data transmission. The energy transmitting module is a laser, used to generate and output energy light for remote power supply. The communication signal light is usually located in the O-band to L-band range, and the energy light is preferably a 980nm wavelength laser. The wavelengths of the two are significantly separated, which facilitates subsequent wavelength division multiplexing and demultiplexing operations.

[0021] The wavelength division multiplexing (WDM) unit, whose input is connected to the optical transmitting unit, is used to combine communication signal light and energy light into a composite beam. The input of this unit is connected to the output of the signal transmitting module and the energy transmitting module respectively. It can combine communication signal light and energy light of different wavelengths into a composite beam with a single optical path. The WDM unit can use thin-film filter type or arrayed waveguide grating type devices to ensure reliable merging of two optical paths with low insertion loss.

[0022] Hollow-core optical fiber, whose input end is connected to the output end of wavelength division multiplexing unit through the first connection unit, is used for the transmission of composite light; The first connection unit is mainly used to realize efficient optical coupling between the output end of the wavelength division multiplexing unit and the input end of the hollow fiber. In this embodiment, the hollow fiber is preferably an anti-resonant hollow fiber with air in its core region, which has low nonlinearity, low transmission loss and high power carrying capacity. The wave demultiplexing unit, whose input end is connected to the output end of the hollow optical fiber through the second connection unit, is used to separate the transmitted composite light wave into communication signal light and high-power energy light. In this process, the composite light from the output end of the hollow fiber enters the wavelength division multiplexing unit through the second connection unit. The structure of the second connection unit corresponds to that of the first connection unit, which is also made of solid fiber and combined with an appropriate coupling method. The function of the wavelength division multiplexing unit is the opposite of that of the wavelength division multiplexing unit. It is used to separate the composite light back into communication signal light and energy light, and output them from different ports respectively.

[0023] It should be noted here that in this embodiment, both the first connecting unit and the second connecting unit are solid-core optical fibers, and the solid-core optical fiber is a first single-mode optical fiber (a large-mode-diameter single-mode optical fiber) whose mode field diameter matches that of the hollow-core optical fiber. The specific connection method is as follows: When the first single-mode fiber is connected to the wavelength division multiplexing unit and the wavelength demultiplexing unit, the corresponding end of the first single-mode fiber needs to be fused tapered to match its mode field with the port mode field of the corresponding device, and then fixedly connected by fusion splicing; while the first single-mode fiber and the hollow fiber are directly connected by bevel fusion splicing to achieve efficient optical coupling.

[0024] The receiving unit is connected to the output of the wavelet demultiplexing unit. It is used to receive the separated communication signal light and energy light, convert the energy light into electrical energy to power the remote equipment of the passive optical network system, and transmit the communication signal light to the user-side optical network terminal.

[0025] The receiving unit includes a signal receiving module and an energy conversion module, wherein: Energy conversion modules are typically photovoltaic converters optimized for the wavelength of light energy. They can efficiently convert received light energy into DC power and power remote devices in a passive optical network system, such as active units, optical amplifiers, or optical network terminals on the user side in remote nodes. The signal receiving module is responsible for transmitting communication signal light to the optical network terminal on the user side, thereby completing photoelectric conversion and user data access.

[0026] Example 2: The main difference between this embodiment and Embodiment 1 lies in the type of solid optical fiber in the first and second connecting units and the coupling method between it and the hollow optical fiber.

[0027] In this embodiment, both the first connection unit and the second connection unit are solid optical fibers, and the solid optical fiber is a second single-mode optical fiber whose mode field diameter does not match that of the hollow optical fiber. Specifically, the second single-mode optical fiber is a conventional single-mode optical fiber conforming to the ITU-T G.652 standard, and its mode field diameter is significantly smaller than that of the hollow optical fiber. The specific connection and coupling methods are as follows: Connection with wavelength division multiplexing (WDM) and wavelength demultiplexing (WDM) units: Since the second single-mode fiber is a standard fiber, its mode field is matched with the port mode field of conventional WDM and WDM units. Therefore, the second single-mode fiber can be directly connected to the output end of the WDM unit and the input end of the WDM unit through conventional fusion splicing without special mode field processing. Coupling with hollow fiber: Since the mode field diameter of the second single-mode fiber is much smaller than that of the hollow fiber, low-loss coupling cannot be achieved through direct fusion splicing. Therefore, in this embodiment, a lens unit is introduced between the second single-mode fiber and the hollow fiber to achieve beam expansion and mode field conversion. The specific implementation of the lens unit includes: External independent lens: An independent focusing lens (such as a spherical lens or an aspherical lens) is set between the output end face of the second single-mode fiber and the input end face of the hollow fiber. This lens collimates and refocuses the diverging beam emitted from the small-diameter second single-mode fiber to match the large mode field of the hollow fiber, thereby achieving efficient optical coupling. The coupling process at the receiving end is symmetrical to this. Solid fiber end integrated lens: At the end of the second single-mode fiber, an integrated spherical lens structure is directly formed by fused taper method. The spherical lens plays the role of beam transformation, shaping the light field in the fiber and coupling it into the hollow fiber. This method has a more compact structure, and the solid fiber at the receiving end can be processed in the same way.

[0028] Example 3: Please see Figure 3 Based on the same technical concept as Embodiment 1 and Embodiment 2, this application also provides Embodiment 3: A method for using a passive optical network system powered by hollow-core optical fiber includes the following steps: S1, Signal and Energy Generation; The passive optical network generates and outputs communication signal light and energy light for power supply through the transmitting unit. Specifically, the signal transmitting module (such as an optical line terminal) in the transmitting unit generates communication signal light located in the O-band to L-band, and the energy transmitting module (such as a laser) generates energy light for remote power supply. The energy light is preferably a laser with a wavelength of 980nm.

[0029] S2, signal and energy combining wave; The wavelength division multiplexing unit combines the communication signal light and the energy light into a composite light beam. By utilizing the filtering or grating characteristics of the wavelength division multiplexer, two optical signals of different wavelengths are combined into the same optical path to form a composite optical signal.

[0030] S3, Composite optical coupling and hollow fiber transmission; The composite light is coupled into the hollow optical fiber through the first connecting unit for long-distance transmission. The first connecting unit can be used in any of the methods in Embodiment 1 and Embodiment 2 to achieve efficient coupling, depending on the system design.

[0031] S4. Composite optical output and demultiplexing; The transmitted composite light is coupled from the hollow fiber to the wavelength division multiplexing unit through the second connection unit, and the coupling method of the second connection unit corresponds to that of the first connection unit to ensure low-loss extraction of the optical signal.

[0032] S5, Signal and energy separation; The composite optical wave is separated into communication signal light and energy light by a wave demultiplexing unit. Utilizing the wavelength selectivity of the wave demultiplexer, signal light and energy light of different wavelengths in the composite light are output from different ports.

[0033] S6. Signal reception and energy utilization; The receiving unit receives the separated communication signal light and energy light, and performs the following operations: The energy light is input to the energy conversion module (such as a photovoltaic converter) and converted into DC power to power the remote equipment of the passive optical network system. The remote equipment includes, but is not limited to, remote nodes, optical amplifiers and user-side optical network terminals. The communication signal light is transmitted to the optical network terminal on the user side through the signal receiving module, and the optical network terminal completes the photoelectric conversion and user data access.

[0034] The method provided in this embodiment achieves simultaneous high-quality communication signal transmission and high-power energy delivery in the same hollow optical fiber through the above steps. It effectively suppresses the nonlinear effects generated by traditional solid optical fiber in high-power laser transmission, avoids signal light quality degradation, and achieves high-power energy light transmission without affecting signal quality. This can reduce system maintenance costs, improve system stability, and provide a good solution for the problem of unstable power supply in remote areas and complex wiring environments.

[0035] In the description of this application, it should be noted that the terms "upper," "lower," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Unless otherwise expressly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two elements. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0036] It should be noted that in this application, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0037] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A passive optical network system based on hollow-core optical fiber, characterized in that, include: The transmitting unit is used to generate and output communication signal light and power energy light for the passive optical network. A wavelength division multiplexing unit, whose input is connected to the optical emitting unit, is used to combine communication signal light and energy light into a composite light beam. A hollow-core optical fiber, the input end of which is connected to the output end of the wavelength division multiplexing unit through a first connection unit, is used for transmitting the composite light; The wave demultiplexing unit has its input end connected to the output end of the hollow optical fiber through a second connection unit, and is used to separate the transmitted composite light wave into communication signal light and high-power energy light. The receiving unit is connected to the output of the wave demultiplexing unit. It is used to receive the separated communication signal light and energy light, convert the energy light into electrical energy to power the remote equipment of the passive optical network system, and transmit the communication signal light to the user-side optical network terminal.

2. The passive optical network system based on hollow-core optical fiber empowerment according to claim 1, characterized in that, The hollow optical fiber is an anti-resonant hollow optical fiber.

3. A passive optical network system based on hollow-core optical fiber empowerment according to claim 1, characterized in that, The first connection unit and the second connection unit are solid optical fibers.

4. A passive optical network system based on hollow-core optical fiber empowerment according to claim 3, characterized in that, The solid fiber is a first single-mode fiber whose mode field diameter matches that of the hollow fiber. The first single-mode fiber is fused to the wavelength division multiplexing unit and the wavelength division demultiplexing unit, and the mode fields at the connection ends are matched. The first single-mode fiber and the hollow fiber are connected by bevel fusion splicing.

5. A passive optical network system based on hollow-core optical fiber empowerment according to claim 3, characterized in that, The solid fiber is a second single-mode fiber whose mode field diameter does not match that of the hollow fiber. The second single-mode fiber is fused to the wavelength division multiplexing unit and the wavelength division demultiplexing unit. The second single-mode fiber and the hollow fiber are optically coupled through a lens unit.

6. A passive optical network system based on hollow-core optical fiber empowerment according to claim 5, characterized in that, The lens unit includes an independent lens disposed between the second single-mode fiber and the hollow fiber, or an integrated lens formed at the end of the second single-mode fiber.

7. A passive optical network system based on hollow-core optical fiber empowerment according to claim 6, characterized in that, The integrated lens is a spherical lens.

8. A passive optical network system based on hollow-core optical fiber empowerment according to claim 1, characterized in that, The transmitting unit includes: The signal transmitting module is used to generate and output communication signal light; Energy emission module, used to generate and output energy light.

9. A passive optical network system based on hollow-core optical fiber empowerment according to claim 6, characterized in that, The receiving unit includes: The signal receiving module is used to transmit communication signal optically to the user-side optical network terminal; Energy conversion module, which is used to convert light energy into electrical energy.

10. A method of using a passive optical network system based on hollow-core fiber empowerment as described in claim 1, characterized in that, Includes the following steps: The transmitting unit generates and outputs communication signal light and energy light for power supply of the passive optical network. The communication signal light and the energy light are combined into a composite light beam by a wavelength division multiplexing unit. The composite light is coupled into a hollow optical fiber for transmission through the first connection unit; The transmitted composite light is coupled from the hollow fiber to the wave decomposition and multiplexing unit through the second connection unit; The composite optical wave decomposition and multiplexing unit separates the composite optical wave into communication signal light and energy light. The receiving unit receives the separated communication signal light and energy light, converts the energy light into electrical energy to power the remote equipment of the passive optical network system, and transmits the communication signal light to the user-side optical network terminal.

Images