阅读说明：本技术 基于多平面光转换的少模模式转换放大的通信接收装置 (Communication receiving device based on few-mode conversion amplification of multi-plane optical conversion ) 是由 张鹏 郭代芳 宫喜宇 程欣 佟首峰 姜会林 于 2021-09-06 设计创作，主要内容包括：基于多平面光转换的模式转换放大的接收装置,属于自由空间激光通信技术领域,为解决现有技术存在的问题,该装置信号源、电信号驱动器与光调制器依次连接,窄线宽激光器、光调制器、光功率放大器、发射天线依次通过单模光纤连接,发射天线过大气湍流与接收天线信,接收天线、光纤传像束和准直器一依次通过光纤连接,光纤准直器一出射光轴以小于法线夹角5°的方式对准空间光调制器,空间光调制器和平面反射镜行放置,准直器二射光轴以小于法线夹角5°的方式对准空间光调制器,准直器二、多芯少模光纤一多芯少模光纤前置光放大器、多芯少模光纤二与多个探测器依次通过光纤连接,多个探测器、多个数模转换器与数模转换器依次通过电缆连接。(A receiving device based on mode conversion amplification of multi-plane optical conversion belongs to the technical field of free space laser communication and aims to solve the problems in the prior art, a signal source of the device, an electric signal driver and an optical modulator are sequentially connected, a narrow-linewidth laser, the optical modulator, an optical power amplifier and a transmitting antenna are sequentially connected through a single-mode optical fiber, the transmitting antenna passes through atmospheric turbulence and receives antenna signals, the receiving antenna, an optical fiber image transmission beam and a collimator are sequentially connected through the optical fiber, an emergent light axis of a first optical fiber collimator is aligned to the spatial optical modulator in a mode of being smaller than a normal included angle by 5 degrees, the spatial optical modulator and a plane reflector are arranged in parallel, a secondary light axis of a second collimator is aligned to the spatial optical modulator in a mode of being smaller than the normal included angle by 5 degrees, a second collimator, a multi-core and few-mode optical fiber one-core optical fiber prepositive optical amplifier, a multi-core and few-mode optical fiber two and a plurality of detectors are sequentially connected through the optical fiber, the detectors, the digital-to-analog converters and the digital-to-analog converters are sequentially connected through cables.)

1. The mode conversion amplification receiving device based on multi-plane optical conversion is characterized by comprising a narrow-linewidth laser (1), a signal source (2), an electric signal driver (3), an optical modulator (4), an optical power amplifier (5), a transmitting antenna (6), a receiving antenna (7), an optical fiber image transmitting beam (8), a first collimator (9), a spatial optical modulator (10), a plane reflector (11), a second collimator (12), a multi-core less-mode optical fiber (13), a multi-core less-mode optical fiber front-mounted optical amplifier (14), a multi-core less-mode optical fiber (15), a plurality of detectors (16), a plurality of digital-to-analog converters (17) and a digital signal processor (18);

the signal source (2), the electric signal driver (3) and the optical modulator (4) are sequentially connected through cables, the narrow-linewidth laser (1), the optical modulator (4), the optical power amplifier (5) and the transmitting antenna (6) are sequentially connected through a single-mode optical fiber, the transmitting antenna (6) communicates with the receiving antenna (7) through atmospheric turbulence, the receiving antenna (7), the optical fiber image transmission beam (8) and the collimator I (9) are sequentially connected through the optical fiber, an emergent optical axis of the optical fiber collimator I (9) is aligned to the spatial optical modulator (10) in a mode of being smaller than a normal included angle by 5 degrees, the spatial optical modulator (10) and the plane reflector (11) are placed in parallel, an incident optical axis of the collimator II (12) is aligned to the spatial optical modulator (10) in a mode of being smaller than the normal included angle by 5 degrees, the collimator II (12), the multi-core less-mode optical fiber I (13), the multi-core less-mode optical fiber prepositive optical amplifier (14), The multi-core few-mode optical fiber II (15) is sequentially connected with the detectors (16) through optical fibers, and the detectors (16) and the digital-to-analog converters (17) are sequentially connected with the digital-to-analog converter (18) through cables.

2. A receiving device of mode conversion amplification based on multi-plane light conversion according to claim 1, characterized in that the optical fiber image transmission beam (8) is used for receiving signal spots to improve the receiving efficiency.

3. The receiving arrangement of mode conversion amplification based on multi-plane light conversion according to claim 1, characterized in that the spatial light modulator (10) is a reflective liquid crystal spatial light modulator for achieving phase conversion of the signal light.

4. The receiving device of mode conversion amplification based on multi-plane light conversion according to claim 1, wherein the spatial light modulator (10) and the plane mirror (11) constitute a multi-plane light conversion component, which can realize mode sampling and multiplexing of dispersed light spots.

5. The receiving device of mode conversion amplification based on multi-plane optical conversion according to claim 1, wherein the multi-core few-mode fiber front-end optical amplifier (14) supports mode number matching with a multi-core few-mode fiber one (13) and a multi-core few-mode fiber two (15).

Technical Field

The invention belongs to the technical field of free space laser communication, and particularly relates to a mode conversion amplification receiving device based on multi-plane optical conversion.

Background

Free space laser communication is a technical means for realizing communication in space by using laser as a carrier, and compared with traditional microwave communication, the free space laser communication has the advantages of high transmission rate, large communication capacity, strong anti-electromagnetic interference performance, high confidentiality and the like, and a communication terminal of the free space laser communication has small volume, low power consumption and high practicability, and gradually becomes a research hotspot in the field of optical communication in recent years. The development and breakthrough of the space laser communication technology are significant for enhancing the real-time performance and safety of space information transmission and future deep space exploration.

In the existing free space laser communication system, an input module at a receiving end receives a laser beam by adopting an optical fiber. However, in the actual atmospheric laser communication receiving process, a relatively large dispersion light spot (about 100 μm in magnitude) often exists, so that the system coupling efficiency is extremely low, the received optical power is weak, and even communication is interrupted. Meanwhile, the light intensity is flickered due to the atmospheric turbulence in the coupling process, and the energy coupled into the optical fiber is also caused to generate time-varying jitter, so that the continuity of communication is interrupted. However, the traditional method for solving the problem of large dispersed light spots is not ideal. For this reason, it is very interesting to further investigate the spatial light-to-fiber coupling problem, especially for large diffuse spots.

The chinese patent application No. 201920621887.4 entitled "spatial optical communication multi-aperture receiving device based on optical fiber coupling", which proposes a spatial optical communication multi-aperture receiving device, the spatial optical communication multi-aperture receiving device includes: the space optical receiving system, a plurality of space optical coupling optical fibers and the photoelectric signal processing system. As shown in fig. 1. The spatial optical communication multi-aperture receiving device can greatly reduce the influence of atmospheric turbulence on a spatial optical communication system and reduce the communication error rate. However, the system has low coupling efficiency of dispersed light spots passing through atmospheric turbulence, is too complex in structure, cannot perform mode conversion, and cannot meet the requirement of free optical communication in ultra-high-speed space.

Disclosure of Invention

The invention provides a mode conversion and amplification receiving device based on multi-plane optical conversion, which aims to solve the problems of low space optical receiving coupling efficiency, jittering and weak received optical power of the existing space laser communication transmission system.

The technical scheme for solving the technical problem of the invention is as follows:

the mode conversion amplification receiving device based on multi-plane optical conversion comprises a narrow-linewidth laser, a signal source, an electric signal driver, an optical modulator, an optical power amplifier, a transmitting antenna, a receiving antenna, an optical fiber image transmitting beam, a first collimator spatial optical modulator, a second plane reflector collimator, a first multi-core less-mode optical fiber, a pre-optical multi-core less-mode optical fiber amplifier, a second multi-core less-mode optical fiber, a plurality of detectors, a plurality of digital-to-analog converters and a digital signal processor;

the signal source, the electric signal driver and the optical modulator are sequentially connected through cables, the narrow-line-width laser, the optical modulator, the optical power amplifier and the transmitting antenna are sequentially connected through single-mode optical fibers, the transmitting antenna is connected with the receiving antenna through atmospheric turbulence, the receiving antenna, the optical fiber image transmission beam and the collimator are sequentially connected through optical fibers, an emergent optical axis of the optical fiber collimator is aligned to the spatial optical modulator in a mode of being smaller than a normal included angle by 5 degrees, the spatial optical modulator and the plane mirror are placed in parallel, an emergent optical axis of the collimator is aligned to the spatial optical modulator in a mode of being smaller than the normal included angle by 5 degrees, the collimator II, the multicore less-mode optical fiber pre-optical amplifier, the multicore less-mode optical fiber pre-optical fiber amplifier, the multicore less-mode optical fiber II and the plurality of detectors are sequentially connected through optical fibers, and the plurality of detectors and the digital-to-analog converters are sequentially connected through cables.

The invention has the beneficial effects that:

1) the invention utilizes the hundred-micron-level optical fiber image transmission bundle to receive signals, the size of the signals is close to that of the dispersed light spots, the receiving efficiency of the dispersed light spots is improved, the coupling light intensity jitter caused by atmospheric turbulence is reduced, and the continuous interruption of communication is avoided.

2) On the basis of the optical fiber image transmission beam, a multi-plane optical converter is used for sampling, converting and classifying modes of dispersed light spots, and then a few-mode amplifier is used for amplifying signals, so that the gain of the signals is improved. The invention has wide application prospect in the fields of laser communication and the like.

Drawings

Fig. 1 is a schematic diagram of a spatial optical communication multi-aperture receiving device in the prior art.

FIG. 2 is a schematic diagram of a communication receiving device with less mode conversion amplification based on multi-plane optical conversion

Schematic representation.

Detailed Description

The present invention will be described in detail with reference to the accompanying drawings.

As shown in fig. 2, the receiving apparatus based on mode conversion amplification of multi-plane optical conversion includes a narrow linewidth laser 1, a signal source 2, an electrical signal driver 3, an optical modulator 4, an optical power amplifier 5, a transmitting antenna 6, a receiving antenna 7, an optical fiber image transmitting beam 8, a first collimator 9, a spatial optical modulator 10, a plane mirror 11, a second collimator 12, a first multicore few-mode fiber 13, a multicore few-mode fiber pre-optical amplifier 14, a second multicore few-mode fiber 15, a plurality of detectors 16, a plurality of digital-to-analog converters 17, and a digital signal processor 18.

The signal source 2, the electric signal driver 3 and the optical modulator 4 are connected in sequence through cables, the narrow linewidth laser 1, the optical modulator 4, the optical power amplifier 5 and the transmitting antenna 6 are connected in sequence through a single mode fiber, the transmitting antenna 6 is communicated with the receiving antenna 7 through atmospheric turbulence, the receiving antenna 7, the optical fiber image transmission beam 8 and the first collimator 9 are connected sequentially through optical fibers, an emergent optical axis of the first optical fiber collimator 9 is aligned to the spatial light modulator 10 in a mode of being smaller than a normal included angle by 5 degrees, the spatial light modulator 10 and the plane mirror 11 are placed in parallel, an incident optical axis of the second collimator 12 is aligned to the spatial light modulator 10 in a mode of being smaller than the normal included angle by 5 degrees, the second collimator 12, the first multicore few-mode optical fiber 13, the preposed multicore few-mode optical fiber optical amplifier 14, the second multicore few-mode optical fiber 15 and the plurality of detectors 16 are connected sequentially through the optical fibers, and the plurality of detectors 16, the plurality of digital-to-analog converters 17 and the digital-to-analog converter 18 are connected sequentially through cables.

The optical fiber image transmission bundle 8 is used for receiving large dispersion signal light spots (hundred microns), and the receiving efficiency is improved.

The spatial light modulator 10 is a reflective liquid crystal spatial light modulator, and is configured to implement phase conversion of signal light.

The spatial light modulator 10 and the plane reflector 11 form a multi-plane light conversion assembly, and mode sampling and multiplexing of dispersed light spots can be realized.

The multi-core few-mode preamplifier 14 supports the mode number to be matched with the first multi-core few-mode fiber 13 and the second multi-core few-mode fiber 15.

The working process of the invention is as follows:

the digital signal sent by the signal source 2 is amplified by the electric signal driver 3 to obtain an amplified electric signal, the electric signal is modulated onto a light carrier generated by the signal laser 1 in a binary mode by the optical modulator 4, then is amplified by the optical power amplifier 5, the amplified signal light is transmitted by the transmitting antenna 6, is subjected to atmospheric turbulence, is received by the receiving antenna 7, is coupled into the optical fiber image transmission beam 8, is incident into the multi-plane optical converter consisting of the spatial optical modulator 10 and the plane mirror 11 by the collimator I9, is subjected to multiple reflection to complete sampling and multiplexing of dispersed light spots, is converted into a plurality of few-mode light spots by a mode, enters the collimator II 12 by the mode converted few-mode light spots, is emitted by the collimator II 12 to enter the few-mode multi-core optical fiber I13, is subjected to signal amplification by the multi-core few-mode optical fiber preposed optical amplifier 14, then enters a plurality of detectors 16 through a few-mode multi-core fiber two 15, converts each optical signal into an electrical signal, then converts each analog signal into a digital signal through a plurality of mode-to-electrical converters 17, and finally performs digital signal processing through a digital signal processor 18.

The above-mentioned embodiments can further change the wavelength, the number of carriers with different wavelengths, etc., and the embodiments are merely descriptions of the preferred embodiments of the present invention, and do not limit the concept and scope of the present invention, and those skilled in the art can make various changes and modifications to the technical solution of the present invention without departing from the design concept of the present invention, and all fall within the protection scope of the present invention.