A self-pulsation-based parallel random signal generating device and method

Abstract

The application relates to the field of laser technology and discloses a parallel random signal generation device and method based on self-pulsation. The device comprises a multimode optical pulse entropy source module, a wavelength division demultiplexing module, an optical-electric conversion module and a peak value judgment module. The multimode optical pulse entropy source module is used for generating a self-pulsation optical pulse sequence with random amplitude and period stability; the wavelength division demultiplexing module is used for separating the self-pulsation optical pulse sequence into multiple optical channels independent of each other according to wavelength differences; the optical-electric conversion module is used for converting the optical pulse sequence in each optical channel into a corresponding electric pulse signal; and the peak value judgment module is used for judging the electric pulse signal once in each optical pulse repetition period and outputting discrete random bits. The application effectively avoids the problems that high-speed electric sampling depends on an external clock, which can cause large sampling jitter, complex system structure and difficulty in integration.

Description

Technical Field

[0001] This invention relates to the field of laser technology, and in particular to a device and method for generating parallel random signals based on self-pulsation. Background Technology

[0002] Random numbers have been widely used in secure communications, radar, and cryptography, and are a core foundation for ensuring system security. Currently, algorithm-based pseudo-random number generators suffer from significant security flaws due to the limited sequence length and periodicity of the generated sequences. In contrast, physical random number generators derived from random physical processes offer advantages such as unpredictability and aperiodicity, fundamentally guaranteeing information security. In particular, chaotic random signals generated based on the nonlinear dynamics of laser systems, characterized by high bandwidth, large-amplitude random fluctuations, and high complexity, have attracted widespread attention to physical random bit generation technology.

[0003] Currently, the main methods for generating random numbers using chaotic lasers are optical feedback semiconductor lasers, optical injection semiconductor lasers, and electro-optic feedback semiconductor lasers. All of these methods obtain continuous-time chaotic signals. To generate digital random numbers, a high-speed electrical analog-to-digital converter (ADC, which includes sample-and-hold circuits, comparators, flip-flops, etc.) is needed in each parallel branch to sample and quantize the continuous chaotic signal, and then perform digital post-processing to obtain the final random bit stream.

[0004] However, continuous chaotic laser-based random number generation schemes have the following drawbacks: First, existing continuous chaotic signals are all achieved by applying external perturbations to single-mode semiconductor lasers, which can only output a single chaotic signal, lacking the potential for parallel output and making it difficult to further increase the random number output rate. Second, during the electrical sampling process, the electronic analog-to-digital converter driven by the electronic sampling clock inevitably generates significant aperture jitter. This jitter introduces uncertainty in the sampling phase, reducing conversion accuracy and signal-to-noise ratio, and causing difficulties in synchronizing subsequent logic circuits such as shift registers and XOR gates. Furthermore, the decision threshold based on the continuous chaotic signal drifts over time, reducing system stability and reliability in engineering applications.

[0005] Existing parallel random number generation schemes based on chaotic lasers generally use continuous chaotic signals as the entropy source for random numbers. They require high-speed electrical analog-to-digital converters (ADCs) and external trigger clocks to electrically sample and quantize each analog signal, ultimately converting it into a discrete digital signal. In this process, the ADC driven by the electronic sampling clock inevitably generates significant aperture jitter, introducing severe sampling errors between the ideal and actual sampling points. This greatly reduces conversion accuracy and signal-to-noise ratio, and causes timing synchronization difficulties in subsequent processing circuits, severely limiting the speed increase of the random number generator and system stability. Furthermore, the addition of external devices increases the overall structural complexity, power consumption, and poses challenges to the integrated design of parallel systems. Summary of the Invention

[0006] To address the problems in existing technologies where each parallel branch relies on high-speed electrical sampling, which in turn leads to large sampling jitter, complex system structure, and difficulty in integration due to the dependence on an external clock, this invention provides a parallel random signal generation device and method based on self-pulsation.

[0007] To solve the above problems, the technical solution of the present invention is as follows: A parallel random signal generation device based on self-pulse includes a multimode optical pulse entropy source module, a wave decomposition and multiplexing module, a photoelectric conversion module, and a peak decision module connected in sequence. The multimode optical pulse entropy source module is used to generate a self-pulsating optical pulse sequence with random amplitude and stable period. The wavelength decomposition and multiplexing module is used to separate the self-pulsating optical pulse sequence into multiple independent optical channels based on wavelength differences. The photoelectric conversion module is used to convert the light pulses in each of the optical channels into corresponding electrical pulse signals; The peak decision module is used to make a decision on the electrical pulse signal once in each optical pulse repetition period, obtain a decision result, and generate corresponding discrete random bits based on the decision result.

[0008] A method for generating parallel random signals based on self-pulses, using the aforementioned device, includes the following steps: S1. Generate a self-pulsating optical pulse sequence with random amplitude and stable period; S2. The self-pulsating optical pulse sequence is separated into multiple independent optical channels based on wavelength differences; S3. Convert the optical pulse sequence in each optical channel into a corresponding electrical pulse signal; S4. Make a decision on the peak value of the electrical pulse signal once in each optical pulse repetition period, obtain the decision result, and output discrete random bits according to the decision result.

[0009] Compared with existing technologies, its advantages are as follows: This invention generates a sequence of optical pulses with randomly fluctuating amplitudes through a self-pulsating mechanism. Leveraging the multi-mode output characteristics of a saturable absorber multimode semiconductor laser (SEL), a wavelet demultiplexer is used to achieve multi-channel parallel processing. Finally, a differential comparator directly determines the peak value of each optical pulse to generate random bits. The self-pulsating optical pulses generated by the SEL exhibit high stability in their repetition period near the operating point, thus eliminating the high-speed clock triggering problem required for continuous chaotic laser electrical sampling. Because the optical pulses output by the multimode self-pulsating laser have a stable repetition period, the occurrence time of each pulse peak can serve as a sampling timing reference, eliminating the need for external clock time alignment. This avoids sampling errors caused by clock jitter in high-speed electrical sampling and avoids the high-speed sampling process and complex digital post-processing required by ADCs. After passing through the wavelet demultiplexer, each channel of the multimode self-pulsating laser can generate discrete random bit sequences using optical pulses without electrical sampling or external clock triggering, thereby achieving simultaneous output of discrete random bit sequences from multiple channels. Attached Figure Description

[0010] Figure 1 This is a block diagram illustrating the principle of the parallel random signal generation device based on self-pulse according to an embodiment of the present invention. Figure 2 This is a schematic diagram of an experimental apparatus for generating parallel random signals based on self-pulses, according to an embodiment of the present invention. Figure 3 This is a spectral feature map of parallel random signal generation based on self-pulse according to an embodiment of the present invention, as well as three different self-pulse sequence diagrams. Figure 4 This is a schematic diagram of a parallel random signal generation device based on self-pulse according to an embodiment of the present invention; Figure 5 This is a flowchart of a parallel random signal generation method based on self-pulse proposed in this invention.

[0011] In the figure, 1-Saturable absorber multimode semiconductor laser; 2-Optical amplifier; 3-Wavelength demultiplexer; 4-Optical coupler; 5-Tunable optical delay line; 6-Photodetector; 7-Differential comparator; 8-Optical isolator; 9-Optical attenuator; 10-Real-time oscilloscope. Detailed Implementation

[0012] The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples. The following examples are for illustrative purposes only and are not intended to limit the scope of the invention.

[0013] Example 1 like Figure 1 As shown in this embodiment, a parallel random signal generation device based on self-pulse includes a multimode optical pulse entropy source module, a wave decomposition and multiplexing module, a photoelectric conversion module, and a peak decision module connected in sequence. A multimode optical pulse entropy source module is used to generate a self-pulsating optical pulse sequence with random amplitude and stable period. A wavelength decomposition and multiplexing module is used to separate the self-pulsating optical pulse sequence into multiple independent optical channels based on wavelength differences; A photoelectric conversion module is used to convert the light pulses in each of the optical channels into corresponding electrical pulse signals; The peak decision module is used to make a decision on the peak value of the electrical pulse signal once in each optical pulse repetition period, obtain the decision result, and generate corresponding discrete random bits based on the decision result.

[0014] In specific implementation, the multimode optical pulse entropy source module includes a saturable absorber multimode semiconductor laser 1. The saturable absorber multimode semiconductor laser 1 is a Fabry-Perot saturable absorber multimode semiconductor laser, also referred to in this invention as a saturable absorber FP-SA semiconductor laser. The saturable absorber multimode semiconductor laser 1 includes a gain region and an absorption region, and further includes a laser chip. The gain region and absorption region are integrated longitudinally along the laser chip and electrically isolated, making them independent of each other. By injecting current into the gain region and applying a reverse bias voltage to the absorption region, the saturable absorber multimode semiconductor laser 1 enters a self-pulsating chaotic state to generate the self-pulsating optical pulse sequence. The generated optical pulse sequence has an adjustable and stable repetition period. The randomness of the pulse amplitude originates from the mismatch in carrier recovery rates between the gain and absorption regions within the laser, as well as mode competition between different modes of the multimode laser. These factors collectively cause the number of photons within the cavity to vary randomly, thus forming a physical entropy source that can be directly used for random number extraction. The multimode optical pulse entropy source module of this invention utilizes an optical pulse sequence output from a self-pulsating laser, whose pulse period has high stability. The peak values ​​of these pulses constitute a precise sampling time reference, thus eliminating the need for an external clock for triggering. This fundamentally avoids sampling errors introduced by clock jitter and significantly improves the stability of the generated random bit sequence.

[0015] In practical implementation, the wave demultiplexing module is used to separate multi-wavelength optical signals into multiple independent optical channels based on wavelength differences, achieving parallel high-speed signal processing and transmission at the physical level. The wave demultiplexing module includes a wave demultiplexer 3, with a saturable absorber multimode semiconductor laser 1 connected to its input. The wave demultiplexer 3 filters the multi-longitudinal-mode chaotic signal generated by the saturable absorber multimode semiconductor laser 1, simultaneously filtering out multiple signals to generate more bits of random numbers. This invention employs a wave demultiplexing module, possessing scalable multi-channel parallel processing capabilities. It can leverage the multi-longitudinal-mode output characteristics of the multimode optical pulse entropy source module combined with the wave demultiplexer to significantly increase the bit rate. By using the multimode optical pulse entropy source module in conjunction with the wave demultiplexer, simultaneous output of more than ten optical pulse signals can be successfully achieved. After passing through a differential comparator, the overall output rate is significantly increased compared to a single channel, greatly expanding the parallel processing capabilities and application scenarios of multimode self-pulsating lasers.

[0016] In practical implementation, the photoelectric conversion module includes at least one photodetector 6, and each output terminal of the wave demultiplexer 3 is connected to one of the photodetectors 6. After wave demultiplexing, the pulses in each independent optical path are converted into corresponding electrical pulse signals by the photodetectors 6 in the photoelectric conversion module. The photodetectors 6 can be any component that can provide sufficient bandwidth to maintain the pulse shape, such as PIN diodes or avalanche photodiodes. The converted electrical pulse signals maintain the periodic characteristics and peak randomness of the optical pulses and serve as the input to the peak decision module.

[0017] In practical implementation, the peak decision module includes at least one differential comparator 7 or a functionally equivalent peak decision circuit, with the photodetector 6 connected to the differential comparator 7. The differential comparator 7 makes a decision on the peak value of the electrical pulse signal once per optical pulse cycle to generate the corresponding discrete random bits. The triggering timing of the differential comparator 7 is naturally limited by the optical pulse cycle, thus requiring no external high-speed clock, sample-and-hold circuit, or high-speed ADC. That is, the decision timing of the differential comparator 7 is determined by the repetition period of the optical pulse sequence itself, without relying on an external high-speed electrical clock, and without requiring an analog-to-digital converter or sample-and-hold circuit. This invention relies only on a laser, photodetector 6, and differential comparator 7 to complete random bit extraction, eliminating the need for a high-speed ADC and its associated circuitry, making the system structure more compact, reducing the number of components, facilitating on-chip integration and mass production, thereby improving overall reliability and reducing power consumption.

[0018] Based on the functional combination of the aforementioned optical pulse entropy source module, wave decomposition and multiplexing module, photoelectric conversion module, and peak decision module, the technical solution proposed in this invention can simultaneously generate multiple discrete random bits. Because the pulse repetition period is stable, this invention avoids sampling offset caused by clock jitter during high-speed electronic sampling; because the pulse peak itself is random, this invention can directly utilize it as an entropy source without complex digital post-processing; since the saturable absorber multimode semiconductor laser 1 used has multiple longitudinal modes, this invention combines wave decomposition and multiplexing to separate and independently generate multiple parallel random numbers by different wavelengths. Compared with existing parallel random number schemes, the technical solution of this invention has a simple structure, strong scalability, and is suitable for scenarios involving multiple high-speed, secure communication and information processing operations simultaneously.

[0019] In the specific implementation process, it also includes an optical amplifier 2. The input end of the optical amplifier 2 is connected to the multimode optical pulse entropy source module, and the output end is connected to the wave decomposition and multiplexing module. The optical amplifier 2 is used to amplify the pulse signal energy of the self-pulsating optical pulse sequence to compensate for the signal loss of the wave decomposition and multiplexing module in the wave decomposition and multiplexing process.

[0020] In the specific implementation process, it also includes an optical coupler 4 and a tunable optical delay line 5. The optical coupler 4 and the tunable optical delay line 5 are disposed between the wave demultiplexing module and the photoelectric conversion module. Each output terminal of the wave demultiplexer is connected to one of the optical couplers 4. The first output terminal of the optical coupler 4 is connected to the input terminal of the tunable optical delay line 5. The output terminal of the tunable optical delay line 5 is connected to the input terminal of a photodetector 6. The output terminal of the photodetector 6 connected to the tunable optical delay line 5 is connected to the positive input terminal of the differential comparator 7. The second output terminal of the optical coupler 4 is connected to the input terminal of another photodetector 6. The output terminal of the photodetector 6 connected to the optical coupler 4 is connected to the negative input terminal of the differential comparator 7.

[0021] This embodiment employs an FP-SA semiconductor laser with a saturable absorber to generate a periodically stable, randomly amplituded optical pulse sequence. A wavelet demultiplexer is used to separate the longitudinal modes of the FP-SA, resulting in multiple independent paths. These paths are then connected to a differential comparator to directly determine the peak value of the optical pulses in each branch. Each path achieves random signal generation without the need for an analog-to-digital converter, sample-and-hold circuitry, or an external high-speed clock. Discrete random bits are directly extracted from the optical domain of each path via a peak decision circuit. This design eliminates the dependence on high-speed analog-to-digital converters and complex sample-and-hold circuits for each path in parallel random number generation schemes, simplifying the structure and facilitating integration.

[0022] Based on the functional combination of the aforementioned optical pulse entropy source module, wavelet decomposition and multiplexing module, photoelectric conversion module, and peak decision module, the technical solution proposed in this invention can simultaneously generate discrete random bits from multiple channels. Since the pulse repetition period is stable, this embodiment avoids sampling offset caused by clock jitter during high-speed electronic sampling. Since the pulse peak itself is random, this embodiment can directly utilize it as an entropy source without complex digital post-processing. Because the saturable absorber multimode semiconductor laser used has multiple longitudinal modes, this embodiment can be combined with wavelet decomposition and multiplexing to achieve multi-channel parallel random number generation by separating and independenting different wavelengths. Compared with existing parallel random number schemes, the technical solution of this embodiment has a simple structure, strong scalability, and is suitable for scenarios involving multiple high-speed, secure communication and information processing simultaneously. It eliminates the dependence on high-speed analog-to-digital converters and complex sample-and-hold circuits for each channel in parallel random number schemes, simplifying the structure and facilitating integration.

[0023] Example 2 In this embodiment, to verify that the self-pulse-based parallel random signal generation device of the present invention can simultaneously output multiple signals, the self-pulse-based parallel random signal generation device of this embodiment includes a multimode optical pulse entropy source module, a wave decomposition and multiplexing module, and a photoelectric conversion module connected in sequence.

[0024] like Figure 2 As shown, the multimode optical pulse entropy source module includes a saturable absorber multimode semiconductor laser 1; the wave demultiplexing module includes a wave demultiplexer 3; and the photoelectric conversion module includes a photodetector 6. Furthermore, the self-pulse-based parallel random signal generation device of this embodiment also includes an optical amplifier 2, an optical isolator 8, and an optical attenuator 9. The saturable absorber multimode semiconductor laser 1, optical amplifier 2, optical isolator 8, and optical attenuator 9 are connected sequentially. The output of the optical attenuator 9 is connected to the input of the wave demultiplexer 3. Each output of the wave demultiplexer 3 is connected to a photodetector 6, and each photodetector 6 is connected to a real-time oscilloscope 10. The optical isolator 8 ensures unidirectional light propagation and prevents light reflected back to the semiconductor laser due to possible end-face reflections in the optical path, thus preventing signal interference. The optical attenuator 9 controls the power entering the optical amplifier 2, as the output power of the semiconductor laser varies with parameters. This control of the power entering the optical amplifier 2 and subsequent instruments protects these instruments from damage due to exceeding their power tolerance limits. The real-time oscilloscope 10 displays a pulse signal that can output random fluctuations on each channel.

[0025] like Figure 3 As shown, the left figure illustrates the self-pulsating optical pulse sequence input to the wavelength demultiplexer 3. In this embodiment, the self-pulsating optical pulse sequence is wavelength demultiplexed using the wavelength demultiplexer 3.Figure 3 In the left figure, the self-pulsating optical pulse sequence shows 20 longitudinal modes in the 1553 nm-1560 nm wavelength band. If a wider wavelength band is selected, more longitudinal modes can be included. In this embodiment, 10 of these modes are filtered out for analysis. The spectrum at this time represents the state of the saturable absorber multimode semiconductor laser 1 in a self-pulsating state. This embodiment... Figure 3 Select three from the left image, such as Figure 3 The left figure illustrates longitudinal modes M1, M2, and M3. Each of these modes, after passing through photodetector 6, is displayed on the real-time oscilloscope 10 as shown below. Figure 3 As shown in the right figure, the longitudinal modulus M1 corresponds to channel 1, the longitudinal modulus M2 corresponds to channel 2, and the longitudinal modulus M3 corresponds to channel 3. Therefore, the parallel random signal generator based on self-pulse in this embodiment can output multiple signals simultaneously to achieve parallel random signal generation.

[0026] Example 3 like Figure 4 As shown, the parallel random signal generation device based on self-pulse in this embodiment includes a multimode optical pulse entropy source module, a wave decomposition and multiplexing module, a photoelectric conversion module, and a peak decision module connected in sequence. A multimode optical pulse entropy source module is used to generate a self-pulsating optical pulse sequence with random amplitude and stable period; a wavelength decomposition and multiplexing module is used to separate the self-pulsating optical pulse sequence into multiple independent optical channels according to wavelength differences; a photoelectric conversion module is used to convert the optical pulse in each optical channel into a corresponding electrical pulse signal; a peak decision module is used to make a decision on the pulse peak of the electrical pulse signal once in each optical pulse repetition period, obtain a decision result, and generate a corresponding discrete random bit based on the decision result.

[0027] The multimode optical pulse entropy source module includes a saturable absorber multimode semiconductor laser 1; the wave demultiplexing module includes a wave demultiplexer 3; the photoelectric conversion module includes a photodetector 6; and the peak decision module includes a differential comparator 7. The saturable absorber multimode semiconductor laser 1 is connected to the input of the wave demultiplexer 3, and each output of the wave demultiplexer 3 is connected to a photodetector 6. Each photodetector 6 is connected to the differential comparator 7.

[0028] In the specific implementation process, it also includes an optical amplifier 2. The input end of the optical amplifier 2 is connected to the multimode optical pulse entropy source module, and the output end is connected to the wave decomposition and multiplexing module. The optical amplifier 2 is used to amplify the pulse signal energy of the self-pulsating optical pulse sequence to compensate for the signal loss of the wave decomposition and multiplexing module in the wave decomposition and multiplexing process.

[0029] In the specific implementation process, it also includes an optical coupler 4 and a tunable optical delay line 5. The optical coupler 4 and the tunable optical delay line 5 are disposed between the wave demultiplexing module and the photoelectric conversion module. Each output terminal of the wave demultiplexer 3 is connected to one of the optical couplers 4. The first output terminal of the optical coupler 4 is connected to the input terminal of the tunable optical delay line 5. The output terminal of the tunable optical delay line 5 is connected to the input terminal of one of the photodetectors 6. The output terminal of the photodetector 6 connected to the tunable optical delay line 5 is connected to the positive input terminal of the differential comparator 7. The second output terminal of the optical coupler 4 is connected to the input terminal of another photodetector 6. The output terminal of the photodetector 6 connected to the optical coupler 4 is connected to the negative input terminal of the differential comparator 7.

[0030] The saturable absorber multimode semiconductor laser 1 adopts an FP-SA (Fabry-Perot Semiconductor Amplifier) ​​structure. The saturable absorber multimode semiconductor laser 1 includes a gain region and an absorption region, and also includes a laser chip. The gain region and absorption region are integrated longitudinally along the laser chip and electrically isolated, making them independent of each other. A driving current Ig is applied to the gain region, and a reverse bias voltage Vsa is applied to the absorption region. By increasing the current, the gain region is adjusted to be in a stimulated emission state. Increasing the voltage in the absorption region improves the absorption capacity and carrier recovery rate of the saturable absorber. At this point, when the gain recovery time of the gain region no longer matches the recovery time of the absorber (i.e., the gain recovery time is faster than the absorber recovery time), the intracavity light intensity cannot remain stable. The generated self-pulse is in a chaotic state, and the output is a sequence of light pulses with a stable repetition period and random fluctuations in pulse peak value.

[0031] Optical amplifier 2 is used to amplify the energy of the output pulse signal to compensate for the loss caused by the input wave demultiplexer 3.

[0032] In this embodiment, the number of channels for wave demultiplexing is set to 10, the pulse period frequency is 2 GHz, and the total generation rate can reach 20 Gbit / s.

[0033] The self-pulsating optical pulse sequence is multi-path parallelized after being input to the wavelength demultiplexer 3 via optical amplifier 2. Each optical path is connected to a different wavelength of the laser, and then split into two paths by optical coupler 4. One path is first connected to a tunable optical delay line 5 and delayed for a predetermined time, which is an integer multiple of the pulse period, before being connected to photodetector 6. The other path is directly connected to photodetector 6, which is used to convert the optical pulse sequence into an electrical pulse signal corresponding to the pulse waveform. In this embodiment, the optical coupler is a 3dB optical coupler.

[0034] The two output electrical pulse signals are respectively input to the positive and negative input terminals of differential comparator 7, used to make a decision on the peak value of the electrical pulse signal within each pulse cycle. Since the self-pulse is a chaotic pulse, the pulse amplitude intensity changes randomly with time. Therefore, in this embodiment, one of the pulses is delayed, and the delayed pulse changes, becoming different from the undelayed pulse. In this embodiment, the delay time of the pulse is an integer multiple of the pulse period. After delaying the pulse by an integer multiple of the pulse period, the peak values ​​of the pulses are aligned, allowing for peak comparison. The comparator outputs a high or low level. If the positive voltage is greater than or equal to the negative voltage, it outputs 1; if the positive voltage is less than the negative voltage, it outputs 0. Therefore, each peak value outputs a 0 or 1 after passing through the differential comparator. A set of pulse timing sequences forms a set of random signals composed of 0s and 1s through this step. Since the repetition period of the optical pulse is stable, the decision time of the comparator is determined by the pulse's own time structure, eliminating the need for an external high-speed electrical clock and avoiding aperture jitter error.

[0035] Example 4 Based on the self-pulsating parallel random signal generation device described in Embodiment 1, this embodiment provides a self-pulsating parallel random signal generation method, such as... Figure 5 As shown, it includes the following steps: S1. Generate a self-pulsating optical pulse sequence with random amplitude and stable period; S2. The self-pulsating optical pulse sequence is separated into multiple independent optical channels based on wavelength differences; S3. Convert the optical pulse sequence in each optical channel into a corresponding electrical pulse signal; S4. Make a decision on the electrical pulse signal once in each optical pulse repetition cycle, obtain the decision result, and output discrete random bits according to the decision result.

[0036] In step S1, a saturable absorber semiconductor laser 1 is used to generate a self-pulsating optical pulse sequence with random amplitude and stable period. The saturable absorber semiconductor laser 1 adopts an FP-SA (Fabry-Perot-Semiconductor Amplifier) ​​structure, with the gain region and absorption region integrated longitudinally along the laser chip and electrically isolated. A driving current Ig is applied to the gain region, and a reverse bias voltage Vsa is applied to the absorption region. By increasing the current, the gain region is adjusted to be in a stimulated emission state. Increasing the voltage in the absorption region improves the absorption capacity and carrier recovery rate of the saturable absorber. At this time, when the gain recovery time of the gain region no longer matches the recovery time of the absorber, that is, the gain recovery time is faster than the recovery time of the absorber, the intracavity light intensity cannot be continuously stabilized. The generated self-pulse is in a chaotic state, and the output is an optical pulse sequence with a stable repetition period and random fluctuations in pulse peak value.

[0037] In the specific implementation process, in step S4, the electrical pulse signal obtained in step S3 is divided into two paths, one being a first signal and the other a second signal. The first signal is delayed by a predetermined time. The decision is made by comparing the peak values ​​of the delayed first signal and the second signal to obtain the decision result. The predetermined time is an integer multiple of the period of the electrical pulse signal.

[0038] Since the self-pulse is a chaotic pulse, its amplitude intensity changes randomly over time. Therefore, in this embodiment, one of the pulses is delayed, resulting in a different pulse than the undelayed one. In this embodiment, the delay time is an integer multiple of the pulse period. Delaying the pulse by an integer multiple of its period aligns the pulse peaks, allowing for peak comparison. The peak values ​​of the delayed first and second signals are compared, resulting in a high or low level output. If the positive voltage is greater than or equal to the negative voltage, a 1 is output; if the positive voltage is less than the negative voltage, a 0 is output. Therefore, each peak value, after passing through a differential comparator, outputs either a 0 or a 1. This process forms a set of random signals composed of 0s and 1s.

[0039] Generally, analog signals are sampled by an ADC that takes values ​​of the analog signal at regular intervals, thereby converting it into a discrete digital signal for further research. However, the saturable absorber multimode semiconductor laser selected in this invention generates pulse signals, and each peak point constitutes a discrete signal, thus eliminating the need for an electric ADC to sample the already discrete points.

[0040] In summary, this invention provides a self-pulsating parallel random signal generation device and method. Compared with existing parallel random number generation techniques based on continuous chaotic light intensity, this invention utilizes a saturable absorber multimode semiconductor laser to generate a self-pulsating optical pulse sequence with random amplitude and stable repetition period. A differential comparator is used to determine the pulse peak value, thereby extracting discrete random bits. This invention effectively avoids clock jitter errors introduced by high-speed electrical sampling, improving the accuracy and stability of random number generation. Existing technologies rely on high-speed external clocks to sample continuous chaotic signals, and the accompanying clock aperture jitter problem leads to uncertainty in sampling timing and a decrease in quantization accuracy. This invention utilizes the optical pulse sequence output by a self-pulsating laser, whose pulse period has high stability. The peak values ​​of these pulses constitute a precise sampling time reference, thus completely eliminating the need for an external clock trigger. This fundamentally avoids sampling errors introduced by clock jitter, significantly improving the stability of the generated random bit sequence. Furthermore, this invention simplifies the structure of the random number generation device, improving the system's integrability and operational reliability. Existing solutions typically require analog-to-digital converters, sample-and-hold circuits, triggers, and post-processing units, resulting in complex system structures and difficulty in achieving high integration. This invention, however, relies solely on a laser, photodetector, and differential comparator to extract random bits, eliminating the need for a high-speed ADC and its associated circuitry. This leads to a more compact system structure, reduced component count, and facilitates on-chip integration and mass production, thereby improving overall reliability and reducing power consumption. Furthermore, by combining the laser with a wavelength demultiplexer, this invention successfully achieves simultaneous output of over a dozen optical pulse signals. After passing through the differential comparator, the overall output rate is several times higher than that of a single signal, significantly expanding the parallel capabilities and application scenarios of saturable absorber multimode semiconductor lasers.

[0041] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and substitutions can be made without departing from the technical principles of the present invention, and these improvements and substitutions should also be considered within the scope of protection of the present invention.

Claims

1. A parallel random signal generation device based on self-pulse, characterized in that, It includes a multimode optical pulse entropy source module, a wave decomposition and multiplexing module, a photoelectric conversion module, and a peak decision module connected in sequence: The multimode optical pulse entropy source module is used to generate a self-pulsating optical pulse sequence with random amplitude and stable period. The wavelength decomposition and multiplexing module is used to separate the self-pulsating optical pulse sequence into multiple independent optical channels based on wavelength differences. The photoelectric conversion module is used to convert the light pulses in each of the optical channels into corresponding electrical pulse signals; The peak decision module is used to make a decision on the peak value of the electrical pulse signal once in each optical pulse repetition period, obtain a decision result, and generate corresponding discrete random bits based on the decision result.

2. The parallel random signal generation device based on self-pulse according to claim 1, characterized in that, The multimode optical pulse entropy source module includes a saturable absorber multimode semiconductor laser (1); the wave demultiplexing module includes a wave demultiplexer (3); the photoelectric conversion module includes at least one photodetector (6); the peak decision module includes at least one differential comparator (7), the saturable absorber multimode semiconductor laser (1) is connected to the input terminal of the wave demultiplexer (3), each output terminal of the wave demultiplexer (3) is connected to one of the photodetectors (6), and each of the photodetectors (6) is connected to the differential comparator (7).

3. The parallel random signal generation device based on self-pulse according to claim 2, characterized in that, In the multimode optical pulse entropy source module, the saturable absorber multimode semiconductor laser (1) includes a gain region and an absorption region. By injecting current into the gain region and applying a reverse bias voltage to the absorption region, the saturable absorber multimode semiconductor laser (1) is made to enter a self-pulsating chaotic state to generate the self-pulsating optical pulse sequence.

4. The parallel random signal generation device based on self-pulse according to claim 2, characterized in that, In the photoelectric conversion module, the photodetector (6) is a component that can provide sufficient bandwidth to maintain the pulse shape.

5. The parallel random signal generation device based on self-pulse according to claim 4, characterized in that, The photodetector (6) is a PIN diode or an avalanche photodiode.

6. The parallel random signal generation device based on self-pulse according to claim 2, characterized in that, It also includes an optical amplifier (2), the input end of which is connected to the multimode optical pulse entropy source module and the output end of which is connected to the wave decomposition and multiplexing module. The optical amplifier (2) is used to amplify the pulse signal energy of the self-pulsating optical pulse sequence to compensate for the signal loss of the wave decomposition and multiplexing module in the wave decomposition and multiplexing process.

7. The parallel random signal generation device based on self-pulse according to claim 2, characterized in that, It also includes an optical coupler (4) and a tunable optical delay line (5). The optical coupler (4) and the tunable optical delay line (5) are disposed between the wave demultiplexing module and the photoelectric conversion module. Each output terminal of the wave demultiplexer (3) is connected to one of the optical couplers (4). The first output terminal of the optical coupler (4) is connected to the input terminal of the tunable optical delay line (5). The output terminal of the tunable optical delay line (5) is connected to the input terminal of one of the photodetectors (6). The output terminal of the photodetector (6) connected to the tunable optical delay line (5) is connected to the positive input terminal of the differential comparator (7). The second output terminal of the optical coupler (4) is connected to the input terminal of another photodetector (6). The output terminal of the photodetector (6) connected to the optical coupler (4) is connected to the negative input terminal of the differential comparator (7).

8. A method for generating parallel random signals based on self-pulsation, based on the parallel random signal generation device based on self-pulsation as described in any one of claims 1-7, characterized in that, Includes the following steps: S1. Generate a self-pulsating optical pulse sequence with random amplitude and stable period; S2. The self-pulsating optical pulse sequence is separated into multiple independent optical channels based on wavelength differences; S3. Convert the optical pulse sequence in each optical channel into a corresponding electrical pulse signal; S4. Make a decision on the electrical pulse signal once in each optical pulse repetition cycle, obtain the decision result, and output discrete random bits according to the decision result.

9. The method according to claim 8, characterized in that, In step S4, the electrical pulse signal obtained in step S3 is divided into two paths, one of which is a first signal and the other is a second signal. The first signal is delayed by a predetermined time. The decision is made by comparing the pulse peak values ​​of the delayed first signal and the second signal to obtain the decision result.

10. The method according to claim 9, characterized in that, In step S4, the predetermined time is an integer multiple of the period of the electrical pulse signal.

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