Single-input double-output multiband optical fiber amplifier
By introducing a mirror into the fiber circulator of multi-band fiber amplifiers, the problem of absorption of short-wavelength gain fibers by long-wavelength gain fibers is solved, and the effect of high gain amplification between short-wavelength and long-wavelength signals is achieved.
Patent Information
- Application Number
- CN202411860910.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-17
- Publication Date
- 2025-03-21
AI Technical Summary
In existing multi-band fiber amplifiers, the absorption problem of long-wavelength gain fibers on short-wavelength gain fibers makes it difficult to achieve high-gain amplification of short-wavelength signals.
A single-input dual-output multi-band fiber amplifier is designed. By introducing a reflector into the fiber circulator, the reflected seed light is amplified in the gain fiber, solving the problem of absorption of short-wavelength gain fiber by long-wavelength gain fiber.
It realizes that in multi-band fiber amplifiers, both short-wavelength and long-wavelength signals can obtain high-gain amplification output, improving the performance of multi-band fiber amplifiers.
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Figure CN119675778A_ABST
Abstract
Description
Technical Field
[0001] The invention discloses a single-input dual-output multi-band optical fiber amplifier, and relates to the field of optical fiber amplifiers. Background Art
[0002] At present, the rapid development of generative artificial intelligence technology has led to an explosive growth in data transmission traffic on global networks, which requires the capacity of existing fiber-optic communication systems to be expanded. In recent years, multi-band transmission technology (MBT) has been considered as one of the effective means to expand the capacity of optical fibers, and one of the most important core components for its development is the multi-band optical amplifier. However, the current mainstream optical amplifier is still the erbium-doped fiber amplifier (EDFA) operating in the C-band, and there is no effective high-performance fiber amplifier that has been widely commercialized in the low-loss communication window from the O-band to the U-band (1260-1675nm) outside the C-band. Therefore, the development of low-loss multi-band fiber amplifiers outside the C-band has become a hot topic in the industry in recent years.
[0003] After years of hard work, bismuth is now considered to be the most promising doping material for the development of near-infrared multi-band fiber amplifiers. Studies have shown that bismuth-doped glass with different doping systems can produce fluorescence effects in the O, E, S and U bands. Furthermore, thanks to the broadband fluorescence properties of bismuth in the near-infrared region, a series of bismuth-doped fiber amplifiers (BDFA) working in new bands have been reported one after another. For example, in 2022, Aleksandr Khegai et al. combined two BDFs to develop a BDFA with a bandwidth of 150nm-6dB, a peak gain >25dB, and an operating range of 1300nm to 1450nm.
[0004] Although directly fusing multiple bismuth-doped fibers can quickly construct a BD FA with broadband amplification, we have found through research that the biggest disadvantage of a broadband BDFA with this structure is that it is difficult to achieve high gain amplification for short-wavelength signals. This is because the radiation peak of the short-wavelength bismuth-doped fiber happens to be the absorption peak of the long-wavelength bismuth-doped fiber, so the amplified short-wavelength signal inevitably becomes the pump of the long-wavelength bismuth-doped fiber and is reabsorbed, which ultimately makes it difficult for the short-wavelength signal to obtain high gain. Summary of the invention
[0005] In order to solve the above-mentioned shortcomings, the present invention uses the existing technology to provide a single-input dual-output multi-band optical fiber amplifier.
[0006] To achieve the above object, the present invention adopts the following technical solutions:
[0007] A single-input multi-output multi-band optical fiber amplifier comprises an optical fiber circulator (1), a wavelength division multiplexer (2), a pump source (3), an isolator (4), a gain optical fiber (5), a wavelength division multiplexer (6), a reflector (7), a wavelength division multiplexer (8), a pump source (9), an isolator (10) and a gain optical fiber (11) which are arranged in sequence.
[0008] The seed light enters from the a port of the circulator (1), and after being output from the b port, it enters the wavelength division multiplexer (2) together with the pump source (3) through the isolator (4), and enters the wavelength division multiplexer (6) through the gain optical fiber (5). Part of the seed light is output to the reflector (7), and the reflected seed light returns to the wavelength division multiplexer (6) again, and enters the wavelength division multiplexer (2) through the gain optical fiber (5), and finally outputs from the c port of the circulator (1). The reflected seed light is amplified, and the pump source (9) enters the wavelength division multiplexer (8) with the remaining seed light after passing through the isolator (10), and is output through the gain optical fiber (11). The remaining seed light is amplified. The present invention utilizes the existing technical conditions to solve the problem of absorption of the short-wavelength gain optical fiber by the long-wavelength gain optical fiber in the multi-band amplifier, so that both bands can achieve high-gain amplification output.
[0009] In the above solution, the reflection wavelength of the reflector (7) is the same as the gain wavelength of the gain optical fiber (5).
[0010] In the above scheme, the gain fiber is a polarization-maintaining fiber or a non-polarization-maintaining fiber; when the gain fiber uses a polarization-maintaining fiber, the fiber circulator is a polarization-dependent fiber circulator or a polarization-independent fiber circulator; when the gain fiber uses a non-polarization-maintaining fiber, the fiber circulator must be a polarization-independent fiber circulator.
[0011] In the above solution, the gain fiber is an active fiber doped with rare earth ions or a bismuth-doped fiber.
[0012] Additional aspects and advantages of the present invention will be given in part in the following description, will be obvious from the following description, or will be learned through embodiments of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS
[0013] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative labor.
[0014] Figure 1 A schematic diagram of a single-input dual-output multi-band fiber amplifier. DETAILED DESCRIPTION
[0015] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.
[0016] Example 1
[0017] See also Figure 1 The schematic diagram of a single-input dual-output multi-band optical fiber amplifier is shown, which comprises an optical fiber circulator (1), a wavelength division multiplexer (2), a pump source (3), an isolator (4), a gain optical fiber (5), a wavelength division multiplexer (6), a reflector (7), a wavelength division multiplexer (8), a pump source (9), an isolator (10) and a gain optical fiber (11) which are arranged in sequence.
[0018] The seed light enters from the a port of the circulator (1), and after being output from the b port, it enters the wavelength division multiplexer (2) together with the pump source (3) through the isolator (4), and enters the wavelength division multiplexer (6) through the gain optical fiber (5). Part of the seed light is output to the reflector (7), and the reflected seed light returns to the wavelength division multiplexer (6) again, and enters the wavelength division multiplexer (2) through the gain optical fiber (5), and finally outputs from the c port of the circulator (1). The reflected seed light is amplified, and the pump source (9) enters the wavelength division multiplexer (8) with the remaining seed light after passing through the isolator (10), and is output through the gain optical fiber (11). The remaining seed light is amplified. The present invention utilizes the existing technical conditions to solve the problem of absorption of the short-wavelength gain optical fiber by the long-wavelength gain optical fiber in the multi-band amplifier, so that both bands can achieve high-gain amplification output.
[0019] A preferred example of this embodiment is as follows: the wavelength of the pump source (3) and the pump source (9) is 1240 nm, the gain fiber (5) and the gain fiber (11) are respectively O-band bismuth-doped fiber and E-band bismuth-doped fiber, the wavelength of the wavelength division multiplexer (6) is O-band / E-band, and the reflection wavelength of the reflector (7) is O-band.
[0020] The above description is only a specific implementation mode of the present invention, and does not limit the patent scope of the present invention. Any equivalent structural transformation made by using the contents of the present invention description and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.
Claims
1. A single-input dual-output multi-band optical fiber amplifier, comprising an optical fiber circulator (1), a wavelength division multiplexer (2), a pump source (3), an isolator (4), a gain optical fiber (5), a wavelength division multiplexer (6), a reflector (7), a wavelength division multiplexer (8), a pump source (9), an isolator (10) and a gain optical fiber (11) arranged in sequence; seed light enters from port a of the circulator (1), is output from port b and enters the wavelength division multiplexer (2) together with the pump source (3) through the isolator (4), enters the wavelength division multiplexer (6) through the gain optical fiber (5), part of the seed light is output to the reflector (7), the reflected seed light returns to the wavelength division multiplexer (6) again, enters the wavelength division multiplexer (2) through the gain optical fiber (5), and finally is output from port c of the circulator (1), the reflected seed light is amplified, the pump source (9) is output from the isolator (10) and the gain optical fiber (11) is output from the isolator (11) and the gain optical fiber (5) is output from the isolator (10), and the seed light is output from the reflector (7), the reflected seed light returns to the wavelength division multiplexer (6), enters the wavelength division multiplexer (2) through the gain optical fiber (5), and finally is output from port c of the circulator (1), the reflected seed light is amplified, the pump source (9) is output from the isolator (10) and the gain optical fiber (11) is output from the isolator (11) and the gain optical fiber (11) is output from the isolator (10 ... After the isolator (10), the light enters the wavelength division multiplexer (8) with the remaining seed light, and is output after passing through the gain optical fiber (11), and the remaining seed light is amplified. The present invention utilizes the existing technical conditions to solve the problem of absorption of the short-wavelength gain optical fiber by the long-wavelength gain optical fiber in the multi-band amplifier, so that both bands can achieve high-gain amplification output; the reflection wavelength of the reflector (7) is the same as the gain wavelength of the gain optical fiber (5); the gain optical fiber (5) and the gain optical fiber (11) are polarization-maintaining optical fibers or non-polarization-maintaining optical fibers. When the gain optical fiber uses the polarization-maintaining optical fiber, the optical fiber circulator is a polarization-dependent optical fiber circulator or a polarization-independent optical fiber circulator. When the gain optical fiber uses the non-polarization-maintaining optical fiber, the optical fiber circulator must be a polarization-independent optical fiber circulator; the gain optical fiber is an active optical fiber doped with rare earth ions or a bismuth-doped optical fiber.