An optical multiplication calculation method and system based on optical fiber stimulated Raman scattering

Abstract

The application discloses an optical multiplication calculation method and system based on optical fiber stimulated Raman scattering, relates to the technical field of optical calculation, and can solve the problems of limited calculation speed and high energy consumption caused by the separation of storage and calculation in the existing electronic calculation architecture. The method comprises the following steps: modulating an electrical signal representing a multiplicand to a first monochromatic laser to generate a pulsed pump laser carrying multiplicand information; modulating an electrical signal representing a multiplier to a second monochromatic laser to generate a pulsed seed laser carrying multiplier information; injecting the pulsed pump laser and the pulsed seed laser from the two ends of an optical fiber to the optical fiber in opposite directions, so that the two beams of light meet in the optical fiber and stimulated Raman scattering occurs, thereby generating stimulated Raman scattering light; the light intensity of the stimulated Raman scattering light and the product of the light intensity of the pulsed pump laser and the light intensity of the pulsed seed laser have a mapping relationship; and the light intensity of the stimulated Raman scattering light is measured by means of a photodetector to obtain a calculation result representing the product of the multiplicand and the multiplier.

Description

Technical Field

[0001] This application relates to the field of optical computing technology, and in particular to an optical multiplication calculation method and system based on stimulated Raman scattering in optical fibers. Background Technology

[0002] With the rapid development of artificial intelligence, big data processing, and high-throughput communication technologies, the demands for computing speed and energy efficiency are increasing exponentially. Multiplication is one of the most fundamental and frequent operations in digital computing, and its implementation directly affects the overall performance of the computing system.

[0003] Currently, the mainstream implementation of multiplication is based on electronic computing technology based on the von Neumann architecture, whose core computing unit is a transistor based on complementary metal-oxide-semiconductor (CMOS) technology. Under this architecture, the processor and memory are physically separated. During multiplication, data needs to be read from memory, transmitted to the processor via a bus to complete the logical operation, and then the result is written back to memory. In addition, in order to overcome the bottleneck of electronic computing, optical computing schemes based on nonlinear crystals, spatial optical paths, or on-chip integrated photonic chips have been proposed in the existing technology, attempting to use the advantages of photons' large bandwidth and low latency to replace or accelerate electronic computing. However, the above-mentioned existing technologies still have the following obvious shortcomings: (1) The von Neumann architecture has a "memory wall" problem. Data is frequently read and written between the processor and memory, resulting in significant time delay and additional energy consumption, which seriously restricts the further improvement of computing speed and energy efficiency. (2) Existing optical computing schemes have complex structures and poor environmental stability. Schemes based on nonlinear crystals or spatial optical paths have extremely high requirements for beam collimation accuracy and mechanical stability. Environmental vibration or temperature changes can easily lead to optical path misalignment, and the device is large in size and difficult to integrate. (3) In the existing optical computing architecture, the transmission medium and the computing unit are physically separated. The optical signal is only used for data transmission in the optical fiber. The physical effects during the transmission process cannot be used to directly complete the calculation, which limits the real-time performance and increases the system latency. (4) The existing optical computing devices are complex and expensive to manufacture. Whether it is the growth of nonlinear crystals or the micro-nano fabrication of photonic integrated chips, it is difficult to have a cost advantage in large-scale applications. Summary of the Invention

[0004] This application provides an optical multiplication calculation method and system based on fiber stimulated Raman scattering, which can solve the problems of limited computing speed and high energy consumption caused by the separation of storage and computation in existing electronic computing architectures, as well as the complex structure, high cost, and inability to directly complete calculations during transmission of existing optical computing solutions.

[0005] To achieve the above objectives, this application adopts the following technical solution: In a first aspect, this application provides an optical multiplication calculation method based on stimulated Raman scattering in optical fibers, the method comprising: An electrical signal representing the multiplicand is modulated onto a first monochromatic laser to generate a pulsed pump laser carrying information about the multiplicand. An electrical signal representing the multiplier is modulated onto a second monochromatic laser to generate a pulsed seed laser carrying multiplier information; The pulsed pump laser and the pulsed seed laser are injected into the optical fiber from opposite ends, so that the two beams meet in the optical fiber and stimulated Raman scattering occurs, generating stimulated Raman scattered light. There is a mapping relationship between the intensity of the stimulated Raman scattered light and the product of the intensity of the pulsed pump laser and the intensity of the pulsed seed laser. The intensity of the stimulated Raman scattering light is measured using a photodetector to obtain the calculation results characterizing the product of the multiplicand and the multiplier.

[0006] In one embodiment, the wavelength of the pulsed pump laser is different from the wavelength of the pulsed seed laser, and the wavelength of the stimulated Raman scattering light is different from both the wavelength of the pulsed pump laser and the wavelength of the pulsed seed laser.

[0007] In one embodiment, injecting the pulsed pump laser and the pulsed seed laser into the optical fiber from opposite ends includes: The pulsed pump laser is injected from the first end of the optical fiber, and the pulsed seed laser is coupled from the second end of the optical fiber into the optical fiber through a wavelength division multiplexer, and is transmitted in the opposite direction to the pulsed pump laser.

[0008] In one embodiment, the photodetector is connected to a wavelength division multiplexer disposed at the seed laser injection end of the optical fiber, for detecting the intensity of stimulated Raman scattering light separated by the wavelength division multiplexer.

[0009] In one embodiment, the method further includes: The pulsed pump laser and / or the pulsed seed laser are pulse sequences containing multiple time segments, with the light intensity of each time segment corresponding to different values, so as to realize the parallel execution of multiple sets of multiplication operations or matrix-vector multiplication operations.

[0010] A second aspect of this application provides an optical multiplication calculation system based on fiber-stimulated Raman scattering, the system comprising: The first monochromatic laser source is used to generate the pump laser; A first electro-optic modulator is used to modulate an electrical signal representing the multiplicand onto the pump laser to generate a pulsed pump laser carrying multiplicand information. A second monochromatic laser source is used to generate seed laser; The second electro-optic modulator is used to modulate an electrical signal representing the multiplier onto the seed laser to generate a pulsed seed laser carrying multiplier information; Optical fiber is used as a common medium for both computing and transmission; A wavelength division multiplexer is disposed at one end of the optical fiber to couple the pulse seed laser into the optical fiber, so that the pulse seed laser and the pulse pump laser are transmitted in opposite directions in the optical fiber and meet, resulting in stimulated Raman scattering and generating stimulated Raman scattered light. The intensity of the stimulated Raman scattered light has a mapping relationship with the product of the intensity of the pulse pump laser and the intensity of the pulse seed laser. A photodetector is used to receive and measure the intensity of the stimulated Raman scattering light, and to obtain the calculation result characterizing the product of the multiplicand and the multiplier using the mapping relationship.

[0011] In one embodiment, the wavelength division multiplexer is disposed at the seed laser injection end of the optical fiber and is used to multiplex the pulsed seed laser with the pump laser transmitted in the optical fiber to realize the opposite transmission of the two beams in the optical fiber.

[0012] In one embodiment, the photodetector is optically coupled to the separation port of the wavelength division multiplexer to detect the intensity of stimulated Raman scattering light separated by the wavelength division multiplexer.

[0013] In one embodiment, the first electro-optic modulator and / or the second electro-optic modulator are intensity modulators used to convert electrical signals into time-domain light intensity signals.

[0014] In one embodiment, the system further includes one or more wavelength division multiplexers and photodetectors for performing multiple sets of multiplication operations in parallel or for implementing matrix-vector multiplication operations.

[0015] The beneficial effects of the technical solutions provided in this application include at least the following: The optical multiplication calculation method based on stimulated Raman scattering in this application provides the following steps: First, an electrical signal representing the multiplicand is modulated onto a first monochromatic laser to generate a pulsed pump laser carrying multiplicand information. Second, an electrical signal representing the multiplier is modulated onto a second monochromatic laser to generate a pulsed seed laser carrying multiplier information. The pulsed pump laser and the pulsed seed laser are injected into the optical fiber from opposite ends, causing the two beams to meet and undergo stimulated Raman scattering, producing stimulated Raman scattered light. A mapping relationship exists between the intensity of the stimulated Raman scattered light and the product of the intensity of the pulsed pump laser and the intensity of the pulsed seed laser. The intensity of the stimulated Raman scattered light is measured using a photodetector to obtain the calculation result characterizing the product of the multiplicand and the multiplier.

[0016] In this application, the time it takes for the pulsed pump laser and the pulsed seed laser to meet in the optical fiber is the time for the multiplication calculation. Because light travels extremely fast in optical fibers, the interaction time between the two beams is typically on the order of femtoseconds to nanoseconds. Therefore, a single multiplication operation can be completed in a very short time, and the number of operations that can be performed per unit time is far higher than that of traditional electronic computing architectures.

[0017] Furthermore, the computation process in this application occurs entirely during optical transmission within the optical fiber, eliminating the need for data to be read from storage units, transmitted to the processor via a bus, and then written back to memory as in traditional von Neumann architectures. The entire computation process avoids frequent access to registers or memory, fundamentally eliminating the time delays and energy consumption associated with data movement.

[0018] Secondly, in this application, the optical fiber serves as both the data transmission medium and the site of computation. As the optical signal propagates forward within the fiber, its stimulated Raman scattering effect performs the multiplication operation. This is fundamentally different from existing optical computing schemes where "transmission is only used for data transmission, and computation must be completed at a specific node." It achieves true online processing—computation while transmission—significantly reducing the overall system latency and complexity.

[0019] Furthermore, all calculations in this application are performed entirely within standard optical fibers, eliminating the need for sophisticated components such as nonlinear crystals, spatial optical paths, or on-chip photonic integrated chips. The fabrication process for standard optical fibers is extremely mature and inexpensive, and can be implemented using general-purpose optical fiber communication devices such as electro-optic modulators, wavelength division multiplexers, and photodetectors. This eliminates the need for advanced semiconductor processes or micro / nano fabrication techniques, resulting in excellent economic viability and scalability. Attached Figure Description

[0020] Figure 1 A structural diagram of an optical multiplication calculation system based on fiber-induced Raman scattering provided in this application embodiment; Figure 2 A flowchart of an optical multiplication calculation method based on stimulated Raman scattering in optical fiber, provided for an embodiment of this application.

[0021] Figure label: 1-First monochromatic laser source, 2-First electro-optic modulator, 3-Fiber optic cable, 4-Wavelength division multiplexer, 5-Second electro-optic modulator, 6-Second monochromatic laser source, 7-Photodetector. Detailed Implementation

[0022] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0023] Hereinafter, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of embodiments of this disclosure, unless otherwise stated, "a plurality of" means two or more.

[0024] In addition, the use of “based on” or “according to” implies openness and inclusivity, because processes, steps, calculations or other actions “based on” or “according to” one or more conditions or values ​​can in practice be based on additional conditions or values ​​beyond those conditions.

[0025] With the rapid development of artificial intelligence, big data processing, and high-throughput communication technologies, the demands for computing speed and energy efficiency are increasing exponentially. Traditional computing tasks mainly rely on electronic computers, whose core computing units are transistors based on complementary metal-oxide-semiconductor (CMOS) technology. In traditional electronic multipliers, multiplication operations are usually implemented through combinations of logic gate circuits (such as AND gates, adders, etc.), and data needs to be stored, transmitted, and processed in binary form.

[0026] Currently, the most mainstream multiplication technique is still based on the von Neumann architecture of electronic computing. In this architecture, the processor and memory are separate. When performing a multiplication operation, the system first needs to read the multiplicand and multiplier from memory, transmit them to the processor's registers via a bus, complete the logical operation in the arithmetic logic unit by switching transistors, and finally write the result back to memory. Although some optical computing schemes have been proposed to try to overcome the bottlenecks of electronic computing, these existing optical computing technologies (such as those based on nonlinear crystals, spatial optical paths, or on-chip integrated photonic chips) still have the following problems: (1) Complex structure and poor environmental stability: Some existing optical computing schemes rely on nonlinear crystals (such as KTP, LiNbO3) or discrete optical lens combinations. These devices usually adopt a spatial optical path structure, which has extremely high requirements for beam collimation accuracy, phase matching conditions and mechanical stability. Even small environmental vibrations or temperature changes can cause optical path misalignment or a significant decrease in computing accuracy, resulting in a large device size that is not only difficult to integrate, but also difficult to adapt to complex and ever-changing application environments.

[0027] (2) The separation of computation and transmission medium fails to achieve true “online” processing: In the existing optical computing architecture, computation must be performed in a specific node (crystal or chip). This architecture, which physically separates the transmission medium from the computing unit, limits the real-time performance of data processing and cannot directly complete the computation using the physical effects of optical signals during transmission, thus increasing the overall complexity and latency of the system.

[0028] (3) Complex manufacturing process and high cost: Whether it is growing high-quality nonlinear crystals or using micro-nano processing technology to manufacture high-precision photonic integrated chips, the manufacturing process is extremely complex and costly. In contrast, the fabrication process of standard optical fibers is extremely mature and inexpensive, and existing high-end optical computing devices are difficult to have a cost advantage in large-scale applications.

[0029] like Figure 1 As shown, the optical multiplication calculation system based on fiber stimulated Raman scattering provided in this application mainly includes: a first monochromatic laser source 1, a first electro-optic modulator 2, an optical fiber 3, a wavelength division multiplexer 4, a second electro-optic modulator 5, a second monochromatic laser source 6, and a photodetector 7.

[0030] The first monochromatic laser source 1 emits a monochromatic laser with a wavelength of λ1, which is modulated onto the pump laser by the multiplier signal by the first electro-optic modulator 2 to form a pulsed pump laser carrying multiplier information. This pulsed pump laser is injected from the first end (left end) of the optical fiber 3 and propagates in the forward direction.

[0031] The second monochromatic laser source 6 emits a monochromatic laser with a wavelength of λ2. The multiplier signal is modulated onto the seed laser by the second electro-optic modulator 5 to form a pulsed seed laser carrying multiplier information. The pulsed seed laser is coupled from the second end (right end) of the optical fiber 3 through the wavelength division multiplexer 4 and transmitted in the reverse direction.

[0032] When two beams of light meet in fiber 3, stimulated Raman scattering occurs, producing stimulated Raman scattered light with a wavelength of λ3. Photodetector 7 receives and measures the intensity of this scattered light through wavelength division multiplexing (WDM) 4, obtaining the multiplication calculation result. A definite mapping relationship exists between the intensity of the stimulated Raman scattered light and the product of the intensities of the pulsed pump laser and the pulsed seed laser; therefore, the measured intensity of the scattered light can characterize the product of the multiplicand and the multiplier.

[0033] To address the aforementioned optical multiplication calculation system based on stimulated Raman scattering in optical fibers, this application provides an optical multiplication calculation method based on stimulated Raman scattering in optical fibers, such as... Figure 2 As shown, the method includes the following steps: Step 201: Modulate the electrical signal representing the multiplicand onto the first monochromatic laser to generate a pulsed pump laser carrying multiplicand information; Step 202: Modulate the electrical signal representing the multiplier onto the second monochromatic laser to generate a pulsed seed laser carrying multiplier information; Step 203: Inject the pulsed pump laser and the pulsed seed laser into the optical fiber from opposite ends, so that the two beams meet in the optical fiber and undergo stimulated Raman scattering to generate stimulated Raman scattered light. There is a mapping relationship between the intensity of the stimulated Raman scattered light and the product of the intensity of the pulsed pump laser and the intensity of the pulsed seed laser. Step 204: Measure the intensity of the stimulated Raman scattering light using a photodetector to obtain the calculation result characterizing the product of the multiplicand and the multiplier.

[0034] The first monochromatic laser source can be a distributed feedback laser (DFB-LD) or a fiber laser, outputting continuous monochromatic laser light with a wavelength λ1. The multiplicand exists in the form of an electrical signal, which can be an analog voltage signal or a digitally coded signal. After receiving this electrical signal, the electro-optic modulator adjusts the laser intensity passing through it in real time according to the signal amplitude, thereby generating a pulse-pumped laser whose intensity varies with the value of the multiplicand. For example, when the value of the multiplicand increases, the output light intensity of the modulator increases accordingly; when the value of the multiplicand decreases, the output light intensity decreases accordingly.

[0035] Similarly, the second monochromatic laser source outputs a continuous monochromatic laser with wavelength λ2, which is modulated by another electro-optic modulator to generate a pulsed seed laser carrying multiplier information. The selection of λ1 and λ2 should satisfy the gain spectrum matching condition of stimulated Raman scattering in optical fibers.

[0036] Pulsed pump laser and pulsed seed laser are injected from opposite ends of an optical fiber. The optical fiber can be a standard single-mode communication fiber, which has mature manufacturing processes, low cost, and extremely low transmission loss. When the two beams propagate towards each other and meet in the fiber, stimulated Raman scattering occurs due to the nonlinear effects of the fiber. During this process, a portion of the pump light's energy is transferred to the seed light through stimulated Raman scattering, simultaneously generating new Stokes photons, i.e., stimulated Raman scattered light. The intensity of this stimulated Raman scattered light has a definite mapping relationship with the product of the pump light intensity and the seed light intensity.

[0037] The photodetector can be a PIN photodiode or an avalanche photodiode (APD), whose output current is proportional to the intensity of the received scattered light. By measuring the output electrical signal of the photodetector, a calculation result proportional to the product of the multiplicand and the multiplier can be obtained.

[0038] This application completes the multiplication calculation process entirely within the fiber optic transmission process, eliminating the need for additional logic gates or arithmetic logic units. The electrical signal directly output by the photodetector corresponds to the product result, making the entire calculation process simple and efficient. The optical fiber itself serves as both the transmission medium and the computation site, enabling true online computation.

[0039] Optionally, the wavelength of the pulsed pump laser is different from the wavelength of the pulsed seed laser, and the wavelength of the stimulated Raman scattering light is different from both the wavelengths of the pulsed pump laser and the pulsed seed laser. This application selects three different wavelengths, allowing the pulsed pump laser, pulsed seed laser, and stimulated Raman scattering light to coexist in the same optical fiber without crosstalk. Furthermore, passive devices such as wavelength division multiplexers can be used to achieve independent separation and detection of each wavelength's optical signal, significantly simplifying the system structure.

[0040] Optionally, injecting the pulsed pump laser and the pulsed seed laser into the optical fiber 3 from opposite ends includes: The pulsed pump laser is injected from the first end of the optical fiber, and the pulsed seed laser is coupled from the second end of the optical fiber into the optical fiber through a wavelength division multiplexer, and is transmitted in the opposite direction to the pulsed pump laser.

[0041] Understandably, the pulsed pump laser is injected directly into the fiber from the first end (defined as the forward injection end). The pulsed seed laser, on the other hand, is coupled into the fiber from the second end (defined as the reverse injection end) via a wavelength division multiplexer (WDM). The WDM is located at the second end of the fiber, with its common port connected to the fiber, its first wavelength port connected to the output of the seed laser source, and its second wavelength port connected to a photodetector. The WDM allows the seed laser with wavelength λ2 to pass through its port and enter the fiber, while simultaneously separating the stimulated Raman scattering light with wavelength λ3 from the fiber to the photodetector port. With this configuration, the pulsed pump laser propagates forward along the fiber, and the pulsed seed laser propagates backward, giving the two beams a chance to meet along the entire length of the fiber.

[0042] This application utilizes a wavelength division multiplexer to achieve coupled injection and counter-propagation of seed lasers, resulting in a simple and reliable structure that eliminates the need for complex optical path alignment. Compared to spatial optical path schemes, the optical path in this embodiment propagates entirely within the optical fiber, unaffected by external vibrations and temperature fluctuations.

[0043] Optionally, the photodetector is connected to a wavelength division multiplexer disposed at the seed laser injection end of the optical fiber, for detecting the intensity of stimulated Raman scattering light separated by the wavelength division multiplexer.

[0044] Specifically, the wavelength division multiplexer separates the optical signals of each wavelength propagating in the optical fiber according to their wavelengths: the pump laser of wavelength λ1 continues to propagate in the optical fiber without interference; the seed laser of wavelength λ2 enters the optical fiber from the seed port; and the stimulated Raman scattering light of wavelength λ3 is output from the separation port of the wavelength division multiplexer and enters the receiving surface of the photodetector.

[0045] It should be noted that the photodetector is located at the seed laser injection end and detects the stimulated Raman scattering light propagating forward (or after separation by a wavelength division multiplexer). This is only one preferred embodiment of this application. In other embodiments of this application, the photodetector may also be located at the pump laser injection end to detect the stimulated Raman scattering light propagating backward.

[0046] Optionally, the method further includes: the pulsed pump laser and / or the pulsed seed laser being a pulse sequence comprising multiple time segments, wherein the light intensity of each time segment corresponds to a different value, so as to realize the parallel execution of multiple sets of multiplication operations or matrix-vector multiplication operations.

[0047] Pulsed pump lasers and / or pulsed seed lasers are not single-segment light pulses, but rather pulse sequences containing multiple time segments. Each time segment corresponds to an independent value, and by adjusting the light intensity amplitude within each time segment, a set of values ​​can be simultaneously applied to different positions within the same light pulse sequence.

[0048] For example, when matrix-vector multiplication is required, each element of the vector can be loaded as the intensity amplitude of light in different time segments into the pulse-pumped laser sequence, while the elements of each row of the matrix can be loaded into the pulse seed laser sequence. When the two pulse sequences meet in the optical fiber, stimulated Raman scattering occurs independently in each corresponding time segment, producing their respective scattered light intensities. The photodetector measures the light intensity of each segment sequentially in the time domain, thus obtaining multiple sets of multiplication results in parallel.

[0049] In other words, this application can not only perform a single multiplication operation, but also perform multiple sets of multiplication operations simultaneously or implement more complex matrix-vector multiplications through time-division multiplexing. This feature makes the present invention particularly suitable for application scenarios that require a large number of parallel multiply-accumulate operations, such as neural network inference and signal processing.

[0050] This application also provides an optical multiplication calculation system based on fiber-induced Raman scattering, such as... Figure 1 As shown, the system includes: The first monochromatic laser source 1 is used to generate pump laser; The first electro-optic modulator 2 is used to modulate an electrical signal representing the multiplicand onto the pump laser to generate a pulsed pump laser carrying multiplicand information. The second monochromatic laser source 6 is used to generate seed laser; The second electro-optic modulator 5 is used to modulate an electrical signal representing the multiplier onto the seed laser to generate a pulsed seed laser carrying multiplier information. Fiber 3 is used as a shared medium for both computing and transmission; A wavelength division multiplexer 4 is disposed at one end of the optical fiber 3 and is used to couple the pulse seed laser into the optical fiber 3, so that the pulse seed laser and the pulse pump laser are transmitted in opposite directions in the optical fiber 3 and meet, resulting in stimulated Raman scattering and generating stimulated Raman scattered light. The intensity of the stimulated Raman scattered light has a mapping relationship with the product of the intensity of the pulse pump laser and the intensity of the pulse seed laser. The photodetector 7 is used to receive and measure the intensity of the stimulated Raman scattering light, and to obtain the calculation result characterizing the product of the multiplicand and the multiplier using the mapping relationship.

[0051] At the system level, the components are connected as follows: the optical output terminal of the first monochromatic laser source 1 is connected to the optical input terminal of the first electro-optic modulator 2, the multiplier signal is input to the electrical signal input terminal of the first electro-optic modulator 2, and the optical output terminal of the first electro-optic modulator 2 is connected to the first end of the optical fiber 3. The optical output terminal of the second monochromatic laser source 6 is connected to the optical input terminal of the second electro-optic modulator 5, the multiplier signal is input to the electrical signal input terminal of the second electro-optic modulator 5, the optical output terminal of the second electro-optic modulator 5 is connected to the first port of the wavelength division multiplexer 4, the common port of the wavelength division multiplexer 4 is connected to the second end of the optical fiber 3, and the separation port of the wavelength division multiplexer 4 is connected to the optical receiving surface of the photodetector 7.

[0052] Under the above connection, the system workflow is as follows: The first monochromatic laser source 1 continuously emits a pump laser with wavelength λ1. The multiplicand electrical signal modulates the pump laser through the first electro-optic modulator 2, forming a pulsed pump laser carrying multiplicand information, which enters from the first end of optical fiber 3. The second monochromatic laser source 6 continuously emits a seed laser with wavelength λ2. The multiplier electrical signal modulates the seed laser through the second electro-optic modulator 5, forming a pulsed seed laser carrying multiplier information, which enters in reverse direction from the second end of optical fiber 3 via wavelength division multiplexer 4. The two beams meet in optical fiber 3, undergoing stimulated Raman scattering to produce result light with wavelength λ3. The result light propagates in optical fiber 3 and reaches the wavelength division multiplexer 4 at the second end, where it is separated and enters photodetector 7. Photodetector 7 outputs an electrical signal corresponding to the product.

[0053] The optical multiplication computing system based on stimulated Raman scattering in this application is entirely composed of standard fiber optic communication devices, requiring no nonlinear crystals, spatial optical paths, or on-chip photonic integrated chips. The system boasts a simple structure, low cost, and high reliability. Power consumption primarily comes from the laser source and electro-optic modulator, significantly lower than that of electronic computing systems with equivalent computing power.

[0054] Optionally, the wavelength division multiplexer 4 is disposed at the seed laser injection end of the optical fiber 3, and is used to perform wavelength multiplexing of the pulsed seed laser and the pump laser transmitted in the optical fiber 3, so as to realize the opposite transmission of the two beams of light in the optical fiber 3.

[0055] Optionally, the photodetector 7 is optically coupled to the separation port of the wavelength division multiplexer 4 to detect the intensity of the stimulated Raman scattering light separated by the wavelength division multiplexer 4.

[0056] In this process, photodetector 7 receives Raman scattered light and converts it into an electrical signal. The amplitude of this electrical signal is linearly related to the intensity of the received scattered light, thus representing the product of the multiplicand and the multiplier.

[0057] Optionally, the first electro-optic modulator 2 and / or the second electro-optic modulator 5 are intensity modulators used to convert electrical signals into time-domain light intensity signals.

[0058] Both the first electro-optic modulator 2 and the second electro-optic modulator 5 employ intensity modulators. The intensity modulator linearly changes the intensity of the output light according to the voltage amplitude of the input electrical signal. When the input voltage is high, the output light intensity increases; when the input voltage is low, the output light intensity decreases; and when the input voltage is zero, the output light intensity can drop to near zero.

[0059] Optionally, the system further includes one or more wavelength division multiplexers 4 and photodetectors 7 for performing multiple sets of multiplication operations in parallel or for implementing matrix-vector multiplication operations.

[0060] Specifically, multiple optical fibers 3 can be arranged in parallel, each optical fiber 3 is equipped with an independent pump laser source, seed laser source, wavelength division multiplexer 4 and photodetector 7, and each channel independently performs multiplication operations, thereby realizing the linear expansion of parallel computing capabilities.

[0061] This application provides an optical multiplication calculation method and system based on stimulated Raman scattering in optical fibers. The entire multiplication calculation is completed during light-speed transmission, with a single operation time on the order of femtoseconds to nanoseconds, which is several orders of magnitude faster than traditional electronic computing. It eliminates the need for frequent reading and writing of intermediate data in registers or memory, completely eliminating the time and energy overhead of data transport and fundamentally solving the storage-read bottleneck of the von Neumann architecture. Furthermore, the optical fiber in this application serves as both the transmission medium and the computing site; the calculation is completed during optical signal transmission, achieving simultaneous transmission and computation. Secondly, this application uses standard optical fibers and general-purpose optical communication devices, eliminating the need for nonlinear crystals, spatial optical paths, or advanced semiconductor processes, resulting in low manufacturing costs and easy large-scale deployment. The all-fiber structure is insensitive to environmental vibrations and temperature changes, eliminating the need for precise optical alignment and constant temperature and humidity environments, thus exhibiting strong adaptability. Furthermore, this application, through flexible programming of time-domain light intensity distribution and modular expansion of parallel channels, can meet different application requirements, ranging from simple multiplication to matrix-vector multiplication, and from single-channel to large-scale parallel computing.

[0062] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0063] The above embodiments merely illustrate several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. An optical multiplication calculation method based on stimulated Raman scattering in optical fibers, characterized in that, The method includes: An electrical signal representing the multiplicand is modulated onto a first monochromatic laser to generate a pulsed pump laser carrying information about the multiplicand. An electrical signal representing the multiplier is modulated onto a second monochromatic laser to generate a pulsed seed laser carrying multiplier information; The pulsed pump laser and the pulsed seed laser are injected into the optical fiber from opposite ends, so that the two beams meet in the optical fiber and stimulated Raman scattering occurs, generating stimulated Raman scattered light. There is a mapping relationship between the intensity of the stimulated Raman scattered light and the product of the intensity of the pulsed pump laser and the intensity of the pulsed seed laser. The intensity of the stimulated Raman scattering light is measured using a photodetector to obtain the calculation results characterizing the product of the multiplicand and the multiplier.

2. The method according to claim 1, characterized in that, The wavelength of the pulsed pump laser is different from the wavelength of the pulsed seed laser, and the wavelength of the stimulated Raman scattering light is different from both the wavelength of the pulsed pump laser and the wavelength of the pulsed seed laser.

3. The method according to claim 1, characterized in that, The step of injecting the pulsed pump laser and the pulsed seed laser into the optical fiber from opposite ends includes: The pulsed pump laser is injected from the first end of the optical fiber, and the pulsed seed laser is coupled from the second end of the optical fiber into the optical fiber through a wavelength division multiplexer, and is transmitted in the opposite direction to the pulsed pump laser.

4. The method according to claim 3, characterized in that, The photodetector is connected to the wavelength division multiplexer and is used to detect the intensity of stimulated Raman scattering light separated by the wavelength division multiplexer.

5. The method according to claim 1, characterized in that, The method further includes: The pulsed pump laser and / or the pulsed seed laser are pulse sequences containing multiple time segments, with the light intensity of each time segment corresponding to different values, so as to realize the parallel execution of multiple sets of multiplication operations or matrix-vector multiplication operations.

6. An optical multiplication calculation system based on stimulated Raman scattering in optical fibers, characterized in that, The system includes: The first monochromatic laser source is used to generate the pump laser; A first electro-optic modulator is used to modulate an electrical signal representing the multiplicand onto the pump laser to generate a pulsed pump laser carrying multiplicand information. A second monochromatic laser source is used to generate seed laser; The second electro-optic modulator is used to modulate an electrical signal representing the multiplier onto the seed laser to generate a pulsed seed laser carrying multiplier information; Optical fiber is used as a common medium for both computing and transmission; A wavelength division multiplexer is disposed at one end of the optical fiber to couple the pulse seed laser into the optical fiber, so that the pulse seed laser and the pulse pump laser are transmitted in opposite directions in the optical fiber and meet, resulting in stimulated Raman scattering and generating stimulated Raman scattered light. The intensity of the stimulated Raman scattered light has a mapping relationship with the product of the intensity of the pulse pump laser and the intensity of the pulse seed laser. A photodetector is used to receive and measure the intensity of the stimulated Raman scattering light, and to obtain the calculation result characterizing the product of the multiplicand and the multiplier using the mapping relationship.

7. The system according to claim 6, characterized in that, The wavelength division multiplexer is located at the seed laser injection end of the optical fiber and is used to multiplex the pulsed seed laser with the pump laser transmitted in the optical fiber, so as to realize the opposite transmission of the two beams in the optical fiber.

8. The system according to claim 7, characterized in that, The photodetector is optically coupled to the separation port of the wavelength division multiplexer and is used to detect the intensity of stimulated Raman scattering light separated by the wavelength division multiplexer.

9. The system according to claim 6, characterized in that, The first electro-optic modulator and / or the second electro-optic modulator are intensity modulators used to convert electrical signals into time-domain light intensity signals.

10. The system according to claim 6, characterized in that, The system also includes at least one set of wavelength division multiplexers and photodetectors. Each wavelength division multiplexer and its corresponding photodetector work together to perform multiple sets of multiplication operations in parallel or to implement matrix-vector multiplication operations.

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