Video transmission device, method and system

Abstract

The invention discloses a video transmission device, method and system. The video transmission device comprises a video signal coding module, a signal generation module, an all-optical modulation module and a video signal decoding module, the output end of the video signal coding module is electrically connected with the input end of the signal generation module; the signal generation module is used for generating signal light and converting the control signal into pump light of a corresponding pulse sequence; the all-optical modulation module is used for modulating to obtain a modulated pulse optical signal and converting the modulated pulse optical signal into a modulated pulse electric signal after transmission is finished; and the video signal decoding module is used for demodulating and decoding the modulation pulse electric signal into a second video signal. According to the invention, end-to-end all-optical video transmission is constructed, the modulator is photonized, signal coding-modulation-demodulation-decoding based on all-optical modulation is realized, and the coding quality and the signal transmission stability in the video transmission process are improved.

Description

Technical Field

[0001] The present invention relates to the field of optical communication technology, and in particular to a video transmission device, method and system. Background Art

[0002] With the rapid development of optical communication technology, the increase in communication rate and the explosive growth of data volume, the demand for data processing speed has gradually increased. At present, optical communication technology has become one of the mainstream technologies for video transmission. However, the transmission speed of electro-optical modulators is limited by the limitation of electrical signal transmission bandwidth on electronic components. They need to be driven by electrical signals, and power consumption increases significantly in high-speed scenarios. At the same time, the frequent conversion of photoelectric and electro-optical signals during the modulation process causes delays in electrical signal processing.

[0003] Furthermore, electro-optic modulators generally use waveguide structures. Optical fibers and waveguides differ in core size, refractive index distribution, and mode propagation constants. When light is coupled from the optical fiber to the waveguide or reversely coupled, a portion of the light energy cannot be effectively transmitted, resulting in increased coupling losses and decreased signal-to-noise ratio. It is difficult to meet the needs of high-speed data processing using electro-optic modulators.

[0004] Therefore, the prior art still needs to be improved and developed. Summary of the invention

[0005] In view of the above-mentioned deficiencies in the prior art, the object of the present invention is to provide a video transmission device, method and system to solve the problem that the optical fiber communication system in the prior art is limited by the signal conversion of the electro-optical modulator, resulting in a significant increase in power consumption in high-speed transmission scenarios, delays in electrical signal processing, and inability to effectively transmit.

[0006] The technical solution of the present invention is as follows: A video transmission device comprises: a video signal encoding module, a signal generating module, an all-optical modulation module and a video signal decoding module; wherein: The output end of the video signal encoding module is electrically connected to the input end of the signal generating module, and is used to provide a first video signal, and pre-process the first video signal to obtain a control signal; The signal generating module is used to generate signal light and convert the control signal into pump light of a corresponding pulse sequence, and emit it to the light incident side of the all-optical modulation module; The all-optical modulation module is electrically connected to the input end of the video signal decoding module, and is used to modulate the signal light based on the power of the pump light to obtain a modulated pulse light signal consistent with the waveform of the pump light, and is used to convert the modulated pulse light signal into a modulated pulse electrical signal after transmission and output it to the video signal decoding module; The video signal decoding module is used to demodulate and decode the modulated pulse electrical signal into a second video signal.

[0007] According to a further configuration of the present invention, the video signal encoding module includes a video signal source and a video signal encoder, and the signal generating module includes a pump light generator and a signal light generator; wherein, The output end of the video signal source is electrically connected to the input end of the video signal encoder, and is used to generate a first video signal to be transmitted; The video signal encoder is electrically connected to the pump light generator and is used to pre-process the first video signal, compress the first video signal, and obtain a control signal; The output end of the pump light generator is connected to the all-optical modulation module, and is used to generate pump light based on the control signal; The output end of the signal light generator is connected to the all-optical modulation module for generating signal light.

[0008] According to a further configuration of the present invention, the all-optical modulation module comprises: a first optical coupler, a first wavelength division multiplexer, a first optical fiber, a second wavelength division multiplexer, a delay line, a first variable optical attenuator, a polarization controller and a second optical coupler; wherein, The first optical coupler is arranged on the optical path of the output end of the signal light generator, the first input end of the first wavelength division multiplexer is arranged on the optical path of the first output end of the first optical coupler, the second input end of the first wavelength division multiplexer is arranged on the optical path of the output end of the pump light generator, and the first wavelength division multiplexer, the first optical fiber, the second wavelength division multiplexer and the first input end of the second optical coupler are connected in sequence on the optical path; the delay line is arranged on the optical path of the second output end of the first optical coupler, the delay line, the first variable optical attenuator, the polarization controller and the second input end of the second optical coupler are connected in sequence on the optical path, and the output end of the second optical coupler is electrically connected to the output end of the video signal decoding module.

[0009] According to a further configuration of the present invention, the all-optical modulation module comprises: a third wavelength division multiplexer and a micro-ring; wherein, The first input end of the third wavelength division multiplexer is arranged on the optical path of the output end of the pump light generator, the second input end of the third wavelength division multiplexer is arranged on the optical path of the output end of the signal light generator, the output end of the third wavelength division multiplexer is connected to the micro-ring on the optical path, and the micro-ring is electrically connected to the output end of the video signal decoding module.

[0010] According to a further configuration of the present invention, the all-optical modulation module comprises: a fourth wavelength division multiplexer, an optical isolator, a third optical coupler, a second optical fiber, a second variable optical attenuator, a first Faraday rotator mirror and a second Faraday rotator mirror; wherein, The first input end of the fourth wavelength division multiplexer is arranged on the optical path of the output end of the pump light generator, the second input end of the fourth wavelength division multiplexer is arranged on the optical path of the output end of the signal light generator, the fourth wavelength division multiplexer, the optical isolator, and the third optical coupler are connected in sequence on the optical path, one end of the second optical fiber and the second end of the third optical coupler are arranged on the same optical path, the first Faraday rotator reflects the light from the optical path on one side of the second optical fiber, one end of the second variable optical attenuator is connected to the third end of the third optical coupler on the optical path, the second Faraday rotator reflects the light from the optical path on one side of the second variable optical attenuator, and the fourth end of the third optical coupler is electrically connected to the output end of the video signal decoding module.

[0011] According to a further configuration of the present invention, the first optical fiber is a hollow-core optical fiber, and the interior of the hollow-core optical fiber is filled with a high-entropy Mxene nonlinear two-dimensional material.

[0012] According to a further configuration of the present invention, the video signal decoding module comprises: an oscilloscope and a video signal decoder; wherein, The input end of the oscilloscope is connected to the output end of the all-optical modulation module, and the output end of the oscilloscope is connected to the input end of the video signal decoder, for presenting the modulated pulse electrical signal in the form of time domain; The video signal decoder is used for demodulating the modulated pulse electrical signal into a second video signal.

[0013] According to a further configuration of the present invention, the video signal decoding module further includes an information processing module, and the information processing module includes: an error detection module and a feedback optimization module; wherein, The error detection module is connected to the signal transmission end of the video signal decoder, and is used to extract error features from the second video signal and the first video signal, and obtain error feature information; One end of the feedback optimization module is connected to the error detection module, and the other end of the feedback optimization module is connected to the video signal encoding module, for analyzing error feature information, identifying error modes, and outputting corresponding feedback signals under the error modes to the video signal encoding module.

[0014] A video transmission method using the video transmission device as described above, the video transmission method comprising: The video signal module provides a first video signal, the first video signal is pre-processed to obtain a control signal, and is input into the signal generation module; The signal generating module generates the pump light and signal light required for all-optical modulation, generates the pump light of the corresponding pulse sequence according to the control signal, and generates the signal light at the same time; The pump light and the signal light are incident on the all-optical modulation module from one side, the pump light modulates the signal light, a modulated pulse light signal consistent with the pump light waveform is obtained and transmitted, and the modulated pulse light signal is converted into a modulated pulse electrical signal after the transmission is completed; The modulated pulse electrical signal is demodulated and decoded into a second video signal in a video signal decoding module.

[0015] A video transmission system comprises the video transmission device as described above, at least one video signal generating device and at least one video signal receiving device, wherein the video signal generating device is connected to the input end of the video signal encoding module of the video transmission device, and the video signal receiving device is connected to the output end of the video signal decoding module of the video transmission device.

[0016] The present invention provides a video transmission device, method and system, wherein the video transmission device includes: a video signal encoding module, a signal generating module, an all-optical modulation module and a video signal decoding module; the output end of the video signal encoding module is electrically connected to the input end of the signal generating module, and is used to provide a first video signal, and pre-process the first video signal to obtain a control signal; the signal generating module is used to generate signal light and convert the control signal into a pump light of a corresponding pulse sequence, and emit it to the light incident side of the all-optical modulation module; the all-optical modulation module is electrically connected to the input end of the video signal decoding module, and is used to modulate the signal light based on the power of the pump light to obtain a modulated pulse light signal consistent with the pump light waveform, and is used to convert the modulated pulse light signal into a modulated pulse electrical signal after the transmission is completed and output it to the video signal decoding module; the video signal decoding module is used to demodulate and decode the modulated pulse electrical signal into a second video signal. The present invention realizes the transmission of video signals by adopting all-optical modulation technology in the signal modulation part and directly modulating optical signals with optical signals, thereby avoiding the conversion process between photoelectric and electro-optical signals and improving the modulation speed; compared with the use of electro-optical modulators, the present invention also reduces the overall transmission loss and increases the bandwidth, thereby improving the signal-to-noise ratio of video transmission. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary personnel in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

[0018] Figure 1 It is a structural schematic diagram of a video transmission device in a preferred embodiment of the present invention.

[0019] Figure 2 It is an interference spectrum diagram of a video transmission device in a preferred embodiment of the present invention.

[0020] Figure 3 It is a diagram of the intensity modulation result of a video transmission device in a preferred embodiment of the present invention.

[0021] Figure 4 It is a structural schematic diagram of a video transmission device in another preferred embodiment of the present invention.

[0022] Figure 5 It is a structural schematic diagram of a video transmission device in another preferred embodiment of the present invention.

[0023] The symbols in the accompanying drawings are: 100, video signal encoding module; 110, video signal source; 120, video signal encoder; 200, signal generating module; 210, pump light generator; 220, signal light generator; 300, all-optical modulation module; 311, first optical coupler; 312, first wavelength division multiplexer; 313, first optical fiber; 314, second wavelength division multiplexer; 315, delay line; 316, first variable optical attenuator; 317, polarization Controller; 318, second optical coupler; 321, third wavelength division multiplexer; 322, microring; 331, fourth wavelength division multiplexer; 332, optical isolator; 333, third optical coupler; 334, second optical fiber; 335, second variable optical attenuator; 336, first Faraday rotator; 337, second Faraday rotator; 400, video signal decoding module; 410, oscilloscope; 420, video signal decoder; 430, information processing module. DETAILED DESCRIPTION

[0024] The present invention provides a video transmission device, method and system. To make the purpose, technical solution and effect of the present invention clearer and more specific, the present invention is further described in detail with reference to the accompanying drawings and examples. 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.

[0025] In the embodiments and the scope of the patent application, unless the text specifically defines the article, "a", "an", "the" and "the" may also include plural forms. If there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of the features.

[0026] It should be further understood that the term "comprising" used in the specification of the present invention refers to the presence of the features, integers, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or groups thereof. It should be understood that when we refer to an element as being "connected" or "coupled" to another element, it can be directly connected or coupled to the other element, or there can be intermediate elements. In addition, the "connection" or "coupling" used herein can include wireless connection or wireless coupling. The term "and / or" used herein includes all or any unit and all combinations of one or more associated listed items.

[0027] Those skilled in the art will understand that, unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as those generally understood by those skilled in the art in the field to which the present invention belongs. It should also be understood that terms such as those defined in common dictionaries should be understood to have meanings consistent with the meanings in the context of the prior art, and will not be interpreted with idealized or overly formal meanings unless specifically defined as here.

[0028] In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the fact that ordinary technicians in the field can implement it. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0029] In traditional information processing and communication systems, electro-optic modulators play a key role, modulating optical signals through electrical signals to achieve data transmission. However, with the increase in communication rates and the explosive growth of data volume, electro-optic modulators face some bottlenecks: the speed of electronic components is limited by the bandwidth of electrical signal transmission, which makes it difficult to meet the needs of high-speed data processing; the electrodes and optical waveguide structure of the electro-optic modulator usually constitute a capacitive load, which can be equivalent to a capacitor C. The driving process of this capacitive load can be regarded as the periodic charging and discharging of the equivalent capacitor, and the energy consumption of each charge and discharge is P0=0.5*C*V 2, where: V is the voltage in the circuit, and C is the capacitance value of the equivalent capacitor. In specific implementation, the electro-optic modulator charges and discharges twice in each cycle as the positive and negative voltages switch, so the dynamic power consumption of the capacitive load in one cycle is: P=C*V 2 *f, where: f is the signal frequency. The power consumption of the electro-optic modulator increases linearly with frequency, which increases the power consumption in high-speed scenarios. At the same time, there are usually differences between the modes of optical fibers and waveguides, especially in terms of core size, refractive index distribution, and mode propagation constants. Since the mode of the optical fiber is usually circular, and the mode of the waveguide may be rectangular or other asymmetric shapes, if the mode of the optical fiber and the mode of the waveguide cannot be well matched, when the light is coupled from the optical fiber to the waveguide or reversely coupled, some of the light energy cannot be effectively transmitted, resulting in coupling loss. When the incident angle between the optical fiber and the waveguide is not appropriate, part of the light will be reflected back to the optical fiber or scattered into the surrounding medium, which will also reduce the coupling efficiency and cause signal loss.

[0030] Based on the existing technology, Figure 1 As shown, the present invention provides a video transmission device, which fully photonizes the modulator, and includes: a video signal encoding module 100, a signal generating module 200, an all-optical modulation module 300 and a video signal decoding module 400; wherein, the output end of the video signal encoding module 100 is electrically connected to the input end of the signal generating module 200, and is used to provide a first video signal, and pre-process the first video signal to obtain a control signal; the signal generating module 200 is used to generate signal light and convert the control signal into a pump light of a corresponding pulse sequence, and emit it to the light incident side of the all-optical modulation module 300; the all-optical modulation module 300 is electrically connected to the input end of the video signal decoding module 400, and is used to modulate the signal light based on the power of the pump light to obtain a modulated pulse light signal consistent with the pump light waveform, and is used to convert the modulated pulse light signal into a modulated pulse electrical signal after the transmission is completed and output it to the video signal decoding module 400; the video signal decoding module 400 is used to demodulate and decode the modulated pulse electrical signal into a second video signal.

[0031] In specific implementation, the video signal encoding module 100 performs photoelectric conversion on the first video signal, preprocesses and encodes the first video signal to obtain a control signal suitable for all-optical modulation, the control signal is an electrical signal, and outputs the control signal to the signal generating module 200. The signal generating module 200 outputs the corresponding pulse sequence of pump light and signal light according to the control signal, and inputs the pump light into the all-optical modulation module 300 to modulate the pump light onto the signal light, so that the pump light is modulated from continuous light to pulse light, and a modulated pulse light signal with the same period as the signal light is obtained and transmitted. After the transmission, the modulated pulse light signal is converted into a modulated pulse electrical signal and input into the video signal decoding module 400. The video signal decoding module 400 may include a computer or a microprocessor, demodulates and decodes the received modulated pulse electrical signal to obtain a second video signal, and outputs a completed video picture stream; at the same time, the error between the second video signal and the initial first video signal parameters is compared, and a feedback signal is output to the input end of the video signal encoding module 100 according to the comparison result, so as to realize dynamic optimization of the working parameters of the all-optical modulated video transmission device.

[0032] Further, the video signal encoding module 100 includes a video signal source 110 and a video signal encoder 120; wherein the output end of the video signal source 110 is electrically connected to the input end of the video signal encoder 120, for generating a first video signal to be transmitted; the output end of the video signal encoder 120 is electrically connected to the input end of the signal generating module 200, for preprocessing the first video signal, compressing the first video signal, and obtaining a control signal. Specifically, the video signal source 110 provides a video signal to be transmitted, and the first video signal can be a video signal collected by the video signal source 110 through a wired or wireless transmission technology, such as ultra-high-definition video, real-time streaming media, etc. Then, the optical domain of the first video signal is preprocessed by the video signal encoder 120. The first video signal is the superposition of multiple image information within a certain period of time, and the image is composed of pixels. Here, the RGB model is used to represent the color of the image, and the value range of each component is usually 0 to 255. Eight-bit binary is used to represent each component, and the optical domain refers to the sum of these pixel points. Converting each pixel of the image into a corresponding binary value is the optical domain preprocessing of the video signal. The video signal is compressed and converted into a digital or analog signal suitable for full optical modulation using H.265 or AV1 encoding to obtain the control signal, and the encoded control signal is stored in the program file.

[0033] Furthermore, the signal generating module 200 includes: a pump light generator 210 and a signal light generator 220; wherein, the input end of the pump light generator 210 is electrically connected to the output end of the video signal encoding module 100, and the output end of the pump light generator 210 is connected to the all-optical modulation module 300, for generating and outputting pump light according to a control signal; the input end of the signal light generator 220 is electrically connected to the output end of the video signal encoding module 100, and the output end of the signal light generator 220 is connected to the all-optical modulation module 300, for generating and outputting signal light.

[0034] In some preferred embodiments of the present invention, the pump light generator 210 uses a 980nm pulse laser. The light source in the 980nm band is applicable to most pulse lasers, and most materials have excellent responses to this band and have a certain degree of universality. Specifically, the 980nm pulse laser reads the programmed program file provided by the video signal encoder 120, and outputs the pump light in a pulse sequence according to the program. The signal light generator 220 uses a 1550nm light source to provide a high-quality optical signal as a carrier for video signal modulation. Furthermore, the signal light generator 220 can also use other narrowband lasers, such as a distributed feedback laser (DFB), which is not limited here. The light source of the signal light generator 220 uses a typical wavelength range of the communication band to meet the high stability and low noise characteristics of all-optical modulation to ensure transmission quality.

[0035] Furthermore, the all-optical modulation module 300 includes: a first optical coupler 311, a first wavelength division multiplexer 312, a first optical fiber 313, a second wavelength division multiplexer 314, a delay line 315, a first variable optical attenuator 316, a polarization controller 317 and a second optical coupler 318; the first optical coupler 311 is arranged on the optical path of the output end of the signal light generator 220, the first input end of the first wavelength division multiplexer 312 is arranged on the optical path of the first output end of the first optical coupler 311, and the second input end of the first wavelength division multiplexer 312 is arranged on the optical path of the first output end of the pump light generator 21 0, the first wavelength division multiplexer 312, the first optical fiber 313, the second wavelength division multiplexer 314 and the first input end of the second optical coupler 318 are connected in sequence on the optical path; the delay line 315 is arranged on the optical path of the second output end of the first optical coupler 311, the delay line 315, the first variable optical attenuator 316, the polarization controller 317 and the second input end of the second optical coupler 318 are connected in sequence on the optical path, and the output end of the second optical coupler 318 is electrically connected to the output end of the video signal decoding module 400.

[0036] In some preferred embodiments of the present invention, the all-optical modulation module 300 adopts an all-optical modulator based on a Mach-Zehnder interferometer (MZI). The Mach-Zehnder interferometer uses the interference principle to control the intensity of the output light through the phase difference, so that the signal modulation can be realized. The Mach-Zehnder interferometer has a simple structure, can be connected in series in multiple stages, and has comb and bandpass filtering characteristics and excellent extinction ratio. It can achieve high contrast when the light is switched between the "on" and "off" states, and provide high-quality signal output. For the modulated signal in video transmission, this high contrast ensures the clarity of the video picture and the integrity of the signal. At the same time, the Mach-Zehnder interferometer has a low insertion loss, can effectively utilize most of the power of the input optical signal, and is also easy to be integrated with other optical devices such as wavelength division multiplexers and amplifiers to form on-chip photonic devices, which are suitable for high-density integrated all-optical communication systems.

[0037] Specifically, the present invention realizes intensity modulation based on the power of the pump light. If the pump light is periodically output at a certain fixed pulse power, the signal light will also be output at the same period, and the signal light is modulated from continuous light into pulse light to obtain the modulated pulse light signal. The pump light generator 210 and the signal light generator 220 are set up, and the pump light generator 210 and the signal light generator 220 respectively emit pump light with a central wavelength of 980nm and signal light with a central wavelength of 1550nm, wherein the pump light is pulse light and the signal light is narrow-band continuous light. When the signal light passes through the first optical fiber 313, part of the light will be absorbed, resulting in the attenuation of the light intensity of one arm where the first optical fiber 313 is located. Therefore, the 1550nm signal light is set to be divided into two paths at a ratio of 9:1 at the first optical coupler 311, and transmitted along the two arms of the Mach-Zehnder interferometer respectively, thereby compensating the light intensity in one arm where the first optical fiber 313 is located, so that the light intensity of the two arms of the Mach-Zehnder interferometer is consistent.

[0038] A first wavelength division multiplexer 312, a second wavelength division multiplexer 314 and a first optical fiber 313 are arranged in one arm of the Mach-Zehnder interferometer. The first optical fiber 313 is a micro-nano hollow core optical fiber, and the hollow core optical fiber is filled with a high entropy transition metal carbon / nitride (Mxene) nonlinear two-dimensional material. The high entropy Mxene nonlinear two-dimensional material has a typical two-dimensional layered structure characteristic and can effectively shield electromagnetic waves. A 0.5g / ml high entropy Mxene nanosheet aqueous solution is filled into the hollow core optical fiber using a pressure difference method, and then heated on a drying platform for 2 hours, and finally a customized ceramic ferrule is used to connect the two ends of the hollow core optical fiber to the jumper. The first optical fiber 313 can be replaced by a D-type optical fiber, a tapered optical fiber, etc., or by other two-dimensional materials with high nonlinear effects and photothermal effects, such as graphene, black phosphorus, and transition metal sulfides, which are not limited by the present invention. The 980nm pulsed light enters the first optical fiber 313 from the first wavelength division multiplexer 312. Based on the good light-to-heat conversion efficiency of nanomaterials, the two-dimensional nanosheets in the hollow-core optical fiber absorb the pulsed light and generate heat, causing the refractive index of the internal material to change to the pulsed light, so that the phase of the 1550nm signal light changes accordingly. Specifically, when the temperature of the hollow-core optical fiber rises, its refractive index changes. This change in refractive index will cause the propagation phase of light in the material to change, thereby achieving phase modulation. The phase change ΔΦ caused by temperature change can be expressed as:

[0039] Where λ is the wavelength of light, ( ) is the derivative of the refractive index with respect to temperature, ΔT is the temperature change, and L is the optical path length. A portion of the 980 nm pump light that has not undergone phase change is output from one path of the second wavelength division multiplexer 314 as the remaining light, while the pump light that has undergone phase change continues to remain in the optical path and is transmitted to the second optical coupler 318.

[0040] In the other arm of the Mach-Zehnder interferometer, a delay line 315, a first variable optical attenuator 316 and a polarization controller 317 are provided, wherein the delay line 315 is used to change the arm length difference between the two arms of the interferometer, thereby controlling the free spectral range. The formulas for the arm length difference and the free spectral range are as follows:

[0041] Among them, λ1 and λ2 are the wavelengths corresponding to the two adjacent maxima in the output interference spectrum, ΔL is the arm length difference, and n is the refractive index of light in the medium. It can be seen that the larger the arm length difference ΔL, the smaller the free spectrum range and the lower the interference contrast; the smaller the arm length difference ΔL, the larger the free spectrum range and the higher the interference contrast. The coherence length is the length at which the light wave remains relatively stable during propagation. If the arm length difference is too large, exceeding the coherence length of the light signal in the two arms, the interference effect will be weakened. If the arm length difference is too small, that is, the free spectrum range is too large, a larger pump power is required to switch from high transmittance to low transmittance during intensity modulation. Therefore, it is necessary to adjust the delay line 315 to select a predetermined arm length difference, so as to find the maximum contrast at the corresponding switching power.

[0042] In order to make the all-optical modulation module 300 in the best working state, it is necessary to debug the parameters in the first variable optical attenuator 316 and the polarization controller 317. During the debugging process, the output end of the second optical coupler 318 is connected to the spectrometer to facilitate the judgment of the debugging results. Among them, the first variable optical attenuator 316 is used to adjust the intensity of the two optical signals so that their intensities are as equal as possible. The polarization controller 317 uses a three-ring structure to control the polarization state of the light by adjusting the rotation angle of the three rings so that the polarization states of the two optical signals are the same. When the intensity and polarization state of the two optical signals are the same, the interference contrast of the interference spectrum output by the all-optical modulation module 300 is adjusted to the maximum value.

[0043] The output end of the second optical coupler 318 is connected to the video signal decoding module 400, and the two optical signals are converged at the second optical coupler 318. The second optical coupler 318 is used as a beam splitting / combining device, which is used to cause a phase shift of π / 2 after the two optical signals are cross-coupled, so that the two optical signals are complementary. Furthermore, the all-optical modulation module 300 also includes a photodetector (not shown in the figure), one end of the photodetector is connected to the output end of the second optical coupler 318 on the optical path, and the other end of the photodetector is electrically connected to the video signal decoding module, which is used to convert the two optical signals into electrical signals. Wherein, the electrical signal is a modulated pulse electrical signal, and the photodetector outputs the modulated pulse electrical signal to the video signal decoding module 400.

[0044] Figure 2 The figure shows the interference spectrum at the output end of the second optical coupler in the present invention, where output 1 and output 2 are respectively the optical signals at the first output end and the second output end of the second optical coupler 318. It can be seen that the interference contrast in the present invention exceeds 20 dB, which is higher than the general interference contrast of 15 dB in the all-optical modulator in the prior art. It can be seen that the transmission quality of the video signal in the all-optical modulation device can be guaranteed in the present invention. Figure 3The figure shows the intensity modulation result of the video transmission device of the present invention when the pump light is 52mW and 25bit / s. The ordinate axis is the relative intensity of different optical signal waveforms. The first row of waveforms is the original waveform of the pump light. It can be obtained that the output ASCII code represents the meaning of "AOM". It can be seen that the present invention can achieve stable transmission of video signals. The waveforms of the second and third rows are the waveforms of the modulated optical signals. It can be seen that under the action of the second optical coupler 318, the waveforms of output 1 and output 2 are complementary. Each bit at output 2 is a bit inversion operation of the corresponding bit of output 1, which has potential application prospects in negative logic systems.

[0045] Further, the video signal decoding module 400 includes: an oscilloscope 410 and a video signal decoder 420; wherein the input end of the oscilloscope 410 is electrically connected to the output end of the all-optical modulation module 300, and the output end of the oscilloscope 410 is electrically connected to the input end of the video signal decoder 420, for presenting the modulated pulse electrical signal in the form of time domain; the video signal decoder 420 is used to demodulate the modulated pulse electrical signal into a second video signal; In a further implementation of some preferred embodiments of the present invention, the video signal decoding module 400 further includes an information processing module 430, which is electrically connected to the output end of the video signal encoding module 100, and is used to compare the second video signal with the first video signal, and output a feedback signal to the video signal encoding module 100 according to the comparison result. The pulse signal received on the oscilloscope 410 is presented on the screen in a time domain manner, and the video signal decoder 420 is used to demodulate the signal to restore the original video signal to obtain the second video signal, and through the decoder, the information lost during the compression process is reversely restored to provide a complete picture stream. The information processing module 430 communicates with the oscilloscope 410, reads the modulated optical signal, and uses an AI algorithm, such as a deep learning or negative feedback neural network parameter adjustment method, to dynamically optimize the working parameters of the all-optical modulator by calculating the correlation fitting input and output algorithm, and to provide feedback to the encoder, thereby adjusting the output parameters of the pump light such as the central wavelength, intensity, etc., to adapt to changes in network conditions and transmitted video content, so as to approach the ideal output effect.

[0046] Further, the information processing module 430 includes: an error detection module and a feedback optimization module (not shown in the figure); wherein the error detection module is connected to the video signal decoder 420, and is used to extract error features from the second video signal and the first video signal, and obtain error feature information; one end of the feedback optimization module is connected to the error detection module, and the other end of the feedback optimization module is connected to the output end of the video signal encoding module 100, and is used to analyze the error feature information and output a corresponding feedback signal to the video signal encoding module 100. Specifically, the error detection module calls the decoded data file to extract the error feature. Exemplarily, the error feature is obtained by measuring the difference between the original signal and the processed signal, and may include image quality indicators such as peak signal-to-noise ratio, structural similarity, block effect, blur, etc. The feedback optimization module can determine which encoding parameters need to be adjusted. Optionally, the feedback optimization module may include a deep learning algorithm or a neural network to identify error patterns and predict parameters that need to be adjusted. After completing the error analysis, the feedback optimization module processes the generated adjustment suggestions and feeds the results back to the encoder to ensure that the system can dynamically adjust the encoding strategy according to the error.

[0047] like Figure 4 As shown, in another preferred embodiment of the present invention, the all-optical modulation module 300 includes: a third wavelength division multiplexer 321 and a micro-ring 322; wherein, the first input end of the third wavelength division multiplexer 321 is arranged on the optical path of the output end of the pump light generator 210, the second input end of the third wavelength division multiplexer 321 is arranged on the optical path of the output end of the signal light generator 220, the output end of the third wavelength division multiplexer 321 is connected to the micro-ring 322 on the optical path, and the micro-ring 322 is electrically connected to the video signal decoding module 400. The structure and working principle of the micro-ring 322 can be obtained without doubt from the prior art, and will not be repeated here.

[0048] like Figure 5As shown, in another preferred embodiment of the present invention, the all-optical modulation module 300 includes: a fourth wavelength division multiplexer 331, an optical isolator 332, a third optical coupler 333, a second optical fiber 334, a second variable optical attenuator 335, a first Faraday rotator mirror 336 and a second Faraday rotator mirror 337; wherein the first input end of the fourth wavelength division multiplexer 331 is arranged on the optical path of the output end of the pump light generator 210, the second input end of the fourth wavelength division multiplexer 331 is arranged on the optical path of the output end of the signal light generator 220, and the fourth wavelength division multiplexer 331, the optical isolator 332, the third optical coupler 333, the second optical fiber 334, the second variable optical attenuator 335, the first Faraday rotator mirror 336 and the second Faraday rotator mirror 337. 32. The third optical coupler 333 is connected in sequence on the optical path, one end of the second optical fiber 334 and the second end of the third optical coupler 333 are arranged on the same optical path, the first Faraday rotator 336 reflects the light from the optical path on one side of the second optical fiber 334, one end of the second variable optical attenuator 335 is connected to the third end of the third optical coupler 333 on the optical path, the second Faraday rotator 337 reflects the light from the optical path on one side of the second variable optical attenuator 335, and the fourth end of the third optical coupler 333 is electrically connected to the output end of the video signal decoding module 400. Specifically, the second variable optical attenuator 335 can be used to balance the intensity of the two optical signals of the interferometer to achieve the best interference contrast. The Faraday rotator acts as a reflector, and stabilizes the polarization state and reduces external environmental interference through the polarization non-reciprocity operation of the Faraday device. After the pump light passes through the second optical fiber 334, the second optical fiber 334 produces a periodic refractive index change, and the signal light is modulated into a pulse signal of the same period, and the pulse signal is a modulated pulse light signal. Optionally, the second optical fiber 334 is prepared in the same manner as the first optical fiber 313 described above, and the second optical fiber 334 is a hollow core optical fiber filled with a high entropy Mxene nonlinear two-dimensional material. The other working principles are the same as those of the all-optical modulator based on the Mach-Zehnder interferometer, and will not be repeated here.

[0049] The present invention also discloses a video transmission method using the video transmission device as described above, the video transmission method comprising: The video signal module provides a first video signal, and the first video signal is pre-processed to obtain a control signal, which is then input into the signal generation module.

[0050] The signal generating module generates pump light and signal light required for all-optical modulation, generates pump light of a corresponding pulse sequence according to a control signal, and generates signal light at the same time.

[0051] The pump light and the signal light are incident on the all-optical modulation module from one side, the pump light modulates the signal light, and a modulated pulse light signal consistent with the pump light waveform is obtained and transmitted, and the modulated pulse light signal is converted into a modulated pulse electrical signal after the transmission is completed.

[0052] The modulated pulse electrical signal is demodulated and decoded into a second video signal in a video signal decoding module. The second video signal is a digital signal for displaying an image. Specifically, the second video signal may be a television signal, a fine image signal or a visual television image signal in NTSC, PAL, or SECAM format. The video transmission method may be as described in an embodiment of a video transmission line device based on all-optical modulation, which will not be described in detail herein.

[0053] The present invention also discloses a video transmission system, which includes the video transmission device as described above, at least one video signal generating device and at least one video signal receiving device, wherein the video signal generating device is connected to the video signal encoding module of the video transmission device, and exemplarily, the video signal generating device can be used to transmit a first video signal to the video signal encoding module. The video signal receiving device is connected to the video signal decoding module of the video transmission device, and the video signal receiving device can display a second video signal. The video transmission device can be specifically as described in an embodiment of a video transmission line device based on all-optical modulation, which will not be described in detail here.

[0054] In summary, the video transmission device, method and system provided by the present invention, by constructing end-to-end all-optical video transmission, photonizes all modulators, has complete information transmission functions, including encoding-modulation-demodulation-decoding of the signal source, and realizes the transmission of video signals using all-optical modulators. At the same time, all-optical modulation technology is used in the signal modulation part, and optical signals are directly modulated by optical signals, so that the conversion process between photoelectric and electro-optical signals is avoided in the transmission of video signals, thereby achieving higher modulation efficiency, reducing losses, and increasing bandwidth, thereby improving the signal-to-noise ratio in the video transmission process.

[0055] It should be understood that the application of the present invention is not limited to the above examples. For ordinary technicians in this field, improvements or changes can be made based on the above description. All these improvements and changes should fall within the scope of protection of the claims attached to the present invention.

Claims

1. A video transmission device, characterized in that: include: Video signal encoding module, signal generation module, all-optical modulation module and video signal decoding module; wherein, The output end of the video signal encoding module is electrically connected to the input end of the signal generating module, and is used to provide a first video signal, and pre-process the first video signal to obtain a control signal; The signal generating module is used to generate signal light and convert the control signal into pump light of a corresponding pulse sequence, and emit it to the light incident side of the all-optical modulation module; The all-optical modulation module is electrically connected to the input end of the video signal decoding module, and is used to modulate the signal light based on the power of the pump light to obtain a modulated pulse light signal consistent with the waveform of the pump light, and is used to convert the modulated pulse light signal into a modulated pulse electrical signal after transmission and output it to the video signal decoding module; The video signal decoding module is used to demodulate and decode the modulated pulse electrical signal into a second video signal.

2. The video transmission device according to claim 1, characterized in that: The video signal encoding module includes a video signal source and a video signal encoder, and the signal generating module includes a pump light generator and a signal light generator; wherein, The output end of the video signal source is electrically connected to the input end of the video signal encoder, and is used to generate a first video signal to be transmitted; The video signal encoder is electrically connected to the pump light generator and is used to pre-process the first video signal, compress the first video signal, and obtain a control signal; The output end of the pump light generator is connected to the all-optical modulation module, and is used to generate pump light based on the control signal; The output end of the signal light generator is connected to the all-optical modulation module for generating signal light.

3. The video transmission device according to claim 2, characterized in that: The all-optical modulation module includes: a first optical coupler, a first wavelength division multiplexer, a first optical fiber, a second wavelength division multiplexer, a delay line, a first variable optical attenuator, a polarization controller and a second optical coupler; wherein, The first optical coupler is arranged on the optical path of the output end of the signal light generator, the first input end of the first wavelength division multiplexer is arranged on the optical path of the first output end of the first optical coupler, the second input end of the first wavelength division multiplexer is arranged on the optical path of the output end of the pump light generator, and the first wavelength division multiplexer, the first optical fiber, the second wavelength division multiplexer and the first input end of the second optical coupler are connected in sequence on the optical path; the delay line is arranged on the optical path of the second output end of the first optical coupler, the delay line, the first variable optical attenuator, the polarization controller and the second input end of the second optical coupler are connected in sequence on the optical path, and the output end of the second optical coupler is electrically connected to the output end of the video signal decoding module.

4. The video transmission device according to claim 2, characterized in that: The all-optical modulation module includes: a third wavelength division multiplexer and a micro-ring; wherein, The first input end of the third wavelength division multiplexer is arranged on the optical path of the output end of the pump light generator, the second input end of the third wavelength division multiplexer is arranged on the optical path of the output end of the signal light generator, the output end of the third wavelength division multiplexer is connected to the micro-ring on the optical path, and the micro-ring is electrically connected to the output end of the video signal decoding module.

5. The video transmission device according to claim 2, characterized in that: The all-optical modulation module comprises: a fourth wavelength division multiplexer, an optical isolator, a third optical coupler, a second optical fiber, a second variable optical attenuator, a first Faraday rotator mirror and a second Faraday rotator mirror; wherein, The first input end of the fourth wavelength division multiplexer is arranged on the optical path of the output end of the pump light generator, the second input end of the fourth wavelength division multiplexer is arranged on the optical path of the output end of the signal light generator, the fourth wavelength division multiplexer, the optical isolator, and the third optical coupler are connected in sequence on the optical path, one end of the second optical fiber and the second end of the third optical coupler are arranged on the same optical path, the first Faraday rotator reflects the light from the optical path on one side of the second optical fiber, one end of the second variable optical attenuator is connected to the third end of the third optical coupler on the optical path, the second Faraday rotator reflects the light from the optical path on one side of the second variable optical attenuator, and the fourth end of the third optical coupler is electrically connected to the output end of the video signal decoding module.

6. The video transmission device according to claim 3, characterized in that: The first optical fiber is a hollow core optical fiber, and the interior of the hollow core optical fiber is filled with high entropy Mxene nonlinear two-dimensional material.

7. The video transmission device according to claim 1, characterized in that: The video signal decoding module includes: an oscilloscope and a video signal decoder; wherein, The input end of the oscilloscope is electrically connected to the output end of the all-optical modulation module, and the output end of the oscilloscope is electrically connected to the input end of the video signal decoder, for presenting the modulated pulse electrical signal in the form of time domain; The video signal decoder is used for demodulating the modulated pulse electrical signal into a second video signal.

8. The video transmission device according to claim 7, characterized in that: The video signal decoding module also includes an information processing module, which includes: an error detection module and a feedback optimization module; wherein, The error detection module is connected to the signal transmission end of the video signal decoder, and is used to extract error features from the second video signal and the first video signal, and obtain error feature information; One end of the feedback optimization module is connected to the error detection module, and the other end of the feedback optimization module is connected to the video signal encoding module, for analyzing error feature information, identifying error modes, and outputting corresponding feedback signals under the error modes to the video signal encoding module.

9. A video transmission method using the video transmission device according to any one of claims 1 to 8, characterized in that: The video transmission method comprises: The video signal module provides a first video signal, the first video signal is pre-processed to obtain a control signal, and is input into the signal generation module; The signal generating module generates the pump light and signal light required for all-optical modulation, generates the pump light of the corresponding pulse sequence according to the control signal, and generates the signal light at the same time; The pump light and the signal light are incident on the all-optical modulation module from one side, the pump light modulates the signal light, a modulated pulse light signal consistent with the pump light waveform is obtained and transmitted, and the modulated pulse light signal is converted into a modulated pulse electrical signal after the transmission is completed; The modulated pulse electrical signal is demodulated and decoded into a second video signal in a video signal decoding module.

10. A video transmission system, characterized in that: It comprises a video transmission device as described in any one of claims 1 to 8, at least one video signal generating device and at least one video signal receiving device, wherein the video signal generating device is connected to the input end of a video signal encoding module of the video transmission device, and the video signal receiving device is connected to the output end of a video signal decoding module of the video transmission device.

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