阅读说明：本技术 一种基于反馈干涉原理的全光真随机数发生器 (All-optical true random number generator based on feedback interference principle ) 是由 王云才 桑鲁骁 张建国 李璞 王安帮 于 2019-10-31 设计创作，主要内容包括：本发明涉及一种基于反馈干涉原理的混沌光熵源,尤其是一种基于反馈干涉原理的全光随机数发生器,应用于保密通信和大规模计算中。一种基于反馈干涉原理的全光真随机数发生器,包括第一3dB耦合器,第一3dB耦合器的输入端输入连续光,作为第一探测信号,第一3dB耦合器的一个输出端顺次连接有第一半导体光放大器和第一波分复用器,第一3dB耦合器的另一个输出端顺次连接有第二半导体光放大器和第二波分复用器；第一波分复用器和第二波分复用器的一个输出端共同连接有第二3dB耦合器的两个输入端。本发明的真随机数产生装置中只需D触发器就可提取出随机码,克服了现有技术因采样过程导致的信号失真带来的附加结构问题,且突破了“电子瓶颈”的限制。(The invention relates to a chaotic light entropy source based on a feedback interference principle, in particular to an all-optical random number generator based on the feedback interference principle, which is applied to secret communication and large-scale calculation. An all-optical true random number generator based on a feedback interference principle comprises a first 3dB coupler, wherein continuous light is input to the input end of the first 3dB coupler and serves as a first detection signal, one output end of the first 3dB coupler is sequentially connected with a first semiconductor optical amplifier and a first wavelength division multiplexer, and the other output end of the first 3dB coupler is sequentially connected with a second semiconductor optical amplifier and a second wavelength division multiplexer; one output end of the first wavelength division multiplexer and one output end of the second wavelength division multiplexer are connected with two input ends of the second 3dB coupler. The random code can be extracted by only using the D trigger in the true random number generating device, so that the additional structure problem caused by signal distortion in the sampling process in the prior art is solved, and the limitation of 'electronic bottleneck' is broken through.)

1. An all-optical true random number generator based on a feedback interference principle is characterized by comprising a first 3dB coupler (1), wherein continuous light is input to the input end of the first 3dB coupler (1) and serves as a first detection signal, one output end of the first 3dB coupler (1) is sequentially connected with a first semiconductor optical amplifier (2) and a first wavelength division multiplexer (4), and the other output end of the first 3dB coupler (1) is sequentially connected with a second semiconductor optical amplifier (3) and a second wavelength division multiplexer (5); one output end of the first wavelength division multiplexer (4) and one output end of the second wavelength division multiplexer (5) are connected with two input ends of a second 3dB coupler (6) together; the optical fiber detection device also comprises a third semiconductor optical amplifier (7) and a circulator (8), continuous light serving as a second detection signal is input at the input end of the third semiconductor optical amplifier (7), the output end of the third semiconductor optical amplifier (7) is connected with the input end of the circulator (8), the reflecting end of the circulator (8) is connected with the output end of a second 3dB coupler (6), the output end of the circulator (8) is connected with a 1 x 3 coupler (9), a first output end of the 1 x 3 coupler (9) is connected with an optical D trigger (13), and the second end of the 1 x 3 coupler (9), the third output end is respectively connected with a first delay optical fiber (10) and a second delay optical fiber (11) with different lengths, the output end of the second delay optical fiber (11) is connected with the other input end of the first wavelength division multiplexer (4), and the output end of the first delay optical fiber (10) is connected with the other input end of the second wavelength division multiplexer (5); the optical D flip-flop (13) outputs an optical random code with the same speed as the optical clock (12) at the output port under the triggering of the optical clock (12).

2. The all-optical true random number generator based on the feedback interference principle of claim 1, wherein the first detection signal and the second detection signal are not the same wavelength.

3. The all-optical true random number generator based on the feedback interference principle of claim 1, wherein neither the first probe signal nor the second probe signal has a power of more than 1 mW.

4. The all-optical true random number generator based on the feedback interference principle as claimed in claim 1, wherein the time difference of the two delay optical fibers is smaller than the carrier recovery time of the third semiconductor optical amplifier (7).

Technical Field

The invention relates to a chaotic light entropy source based on a feedback interference principle, in particular to an all-optical random number generator based on the feedback interference principle, which is applied to secret communication and large-scale calculation.

Background

Random numbers have wide application in scientific computing such as Monte Carlo (Monte Carlo) simulation, statistical sampling, artificial neural networks, and the like. In particular, in the field of secure communication, generating secure and reliable random numbers (also called keys) is related to many aspects such as national defense security, financial stability, business confidentiality, personal privacy, and the like.

The information theory nose ancestor shannon proposes: absolutely secure secret communication requires the use of the one-time pad encryption theory. Three conditions are proposed for the random number generation apparatus: 1) the length of the key is not shorter than that of the plaintext; 2) the key is completely random; 3) the key cannot be reused. This requires the generation of large, real-time numbers of true random numbers with code rates not lower than the communication rate.

Random number generators can be divided into two categories: pseudo-random number generators and true-random number generators. Pseudo-random number generators can conveniently generate fast random numbers with a certain period by giving different seeds to some deterministic algorithms. With the continuous improvement of the computing power of a computer, the event that the pseudo-random number is cracked by taking the pseudo-random number as a key is endless, and the information security is seriously threatened.

The true random number generator can ensure the accuracy of scientific calculation and the safety of secret communication, and can generate unpredictable and non-periodic completely random true random numbers by using a microscopic quantum mechanism or a macroscopic random phenomenon in nature as a physical entropy source. The physical entropy sources selected by the traditional true random number generator are mostly thermal noise, spontaneous radiation noise, nuclear radiation decay, phase noise of an oscillator, chaotic circuits and the like of resistors or other electronic elements. The code rate is in Mb/s order, and has a huge gap with the transmission rate of modern high-speed information.

In recent years, due to the emergence of a novel random physical entropy source of chaotic light, a true random number is developed in a breakthrough manner in the aspect of production rate. In 2008, the chaos optical entropy source was first utilized by Tian Chunhu project group in Japan on Nature Photonics to realize the online and real-time generation of 1.7 Gb/s true random number [ Nat. photon, vol.2, pp.728-732, 2008 ]. In 2013 and 2018, the topic group of the applicant successfully constructs a true random code generator with code rates of 4.5 Gb/s and 10Gb/s by using chaotic light [ Opt. Express, 21 (17): 20452-.

However, in the existing true random number real-time generation technology based on chaotic light, a photoelectric detector is generally adopted to convert chaotic signals emitted by the photoelectric detector into electric signals, an ADC is utilized to sample and quantize the corresponding electric signals in an electric domain, and then a certain post-processing technology is combined to realize the generation of high-speed true random codes; or sampling the chaotic signal in the optical domain, converting the chaotic signal into an electric pulse signal by using a photoelectric detector, and quantizing and post-processing the corresponding electric sampling signal in the electric domain to realize the generation of the high-speed true random code.

As the rate of optical communication increases, the way in which such optical-electrical-optical generation of random numbers tends to be constrained by "electronic bottlenecks". And the sampling and quantizing device generated by the random number is complex at present, and the random code with good randomness can be obtained only by carrying out post-processing.

Disclosure of Invention

The invention provides an all-optical true random number generator based on a feedback interference principle, aiming at solving the technical problems that the existing all-optical random numbers are required to be subjected to optical-electrical-optical conversion, cannot meet the requirements of a modern optical communication system, are complex in sampling and quantizing devices and can obtain random codes with good randomness only by carrying out post-processing.

The invention is realized by adopting the following technical scheme: an all-optical true random number generator based on a feedback interference principle comprises a first 3dB coupler, wherein continuous light is input to the input end of the first 3dB coupler and serves as a first detection signal, one output end of the first 3dB coupler is sequentially connected with a first semiconductor optical amplifier and a first wavelength division multiplexer, and the other output end of the first 3dB coupler is sequentially connected with a second semiconductor optical amplifier and a second wavelength division multiplexer; one output end of the first wavelength division multiplexer and one output end of the second wavelength division multiplexer are connected with two input ends of the second 3dB coupler; the optical fiber coupler also comprises a third semiconductor optical amplifier and a circulator, wherein continuous light serving as a second detection signal is input into the input end of the third semiconductor optical amplifier, the output end of the third semiconductor optical amplifier is connected with the input end of the circulator, the reflection end of the circulator is connected with the output end of a second 3dB coupler, the output end of the circulator is connected with a 1 multiplied by 3 coupler, the first output end of the 1 multiplied by 3 coupler is connected with an optical D trigger, the second and third output ends of the 1 multiplied by 3 coupler are respectively connected with a first delay optical fiber and a second delay optical fiber, the output end of the second delay optical fiber is connected with the other input end of the first wavelength division multiplexer, and the output end of the first delay optical fiber is connected with the other input end of the second wavelength division multiplexer; the optical D flip-flop outputs an optical random code with the same speed as the optical clock at the output port under the triggering of the optical clock.

A first detection light signal is input from an A end and is divided into two paths by a first 3dB coupler 1, and the upper path enters a second 3dB coupler 6 by a first semiconductor light amplifier 2 and a first wavelength division multiplexer 4; the lower path enters a second 3dB coupler 6 through a second semiconductor optical amplifier 3 and a second wavelength division multiplexer 5. The first 3dB coupler 1, the first semiconductor optical amplifier 2, the second semiconductor optical amplifier 3, the first wavelength division multiplexer 4, the second wavelength division multiplexer 5 and the second 3dB coupler 6 form an SOA-MZI (Mach-Zehnder interferometer based on the semiconductor optical amplifier). Under the condition that no high-power feedback signal is injected into the first semiconductor optical amplifier 2 and the second semiconductor optical amplifier 3 to consume the current carriers of the first semiconductor optical amplifier and the second semiconductor optical amplifier, two beams of continuous light undergo the same gain and phase change, so the interference is cancelled, and the output signal passes through the circulator 8 to the third semiconductor optical amplifier 7 without consuming the current carriers of the third semiconductor optical amplifier. Continuous light is input into a port B to serve as a second detection light signal, high-power continuous light is output through a third semiconductor optical amplifier 7, the high-power continuous light is divided into three paths through a circulator 8 and a 1 x 3 coupler 9, and one path of the high-power continuous light is fed back to the second semiconductor optical amplifier 3 through a first delay optical fiber 10 and a second wavelength division multiplexer 5; one path is fed back to the first semiconductor optical amplifier 2 through the second delay optical fiber 11 and the first wavelength division multiplexer 4.

It should be noted here that the lengths of the first delay fiber 10 and the second delay fiber 11 are not uniform. Therefore, the time of the two feedback signals reaching the first semiconductor optical amplifier 2 and the second semiconductor optical amplifier 3 is different, the upper arm detection signal and the lower arm detection signal experience different phase differences, so that the interference of the second 3dB coupler 6 is long, the output signal passes through the circulator 8 to the third semiconductor optical amplifier 7, and a large amount of current carriers are consumed. The second probe optical signal input at the B port is led to output low-power continuous light through the third semiconductor optical amplifier 7, and then divided into three paths through the 1 × 3 coupler 9, wherein two paths are used as feedback, and the other path is connected to the data input end of the optical D flip-flop 13.

Since the delay difference between the first delay fiber 10 and the second delay fiber 11 is smaller than the carrier recovery time of the SOA (third semiconductor optical amplifier) used, so that the SOA gain recovery is incomplete, and the SOA-MZI interferes to output an abnormal signal. The process is circulated in sequence, and then the chaotic optical signal is output from the 1 × 3 coupler 9, and then the chaotic optical signal passes through the optical D trigger, and under the trigger of the optical clock, the optical random code with the same speed as the optical clock is output from the C port.

The invention has the beneficial effects that:

firstly, the random code can be extracted only by the D trigger in the true random number generating device, so that the problem of an additional structure caused by signal distortion in the sampling process in the prior art is solved;

secondly, the signal processing process of the true random number generating device is carried out in the optical domain, and any photoelectric conversion device and electronic analog-to-digital conversion equipment are not needed, so that the limitation of 'electronic bottleneck' is broken through;

thirdly, the true random number generating device of the invention can be directly compatible with an optical network without any external modulator, thereby overcoming the technical limitation of the prior random number generator when being applied to the optical communication network.

Drawings

FIG. 1 is a schematic diagram of the structure of the present invention.

1. A first 3dB coupler 2, a first semiconductor optical amplifier 3 and a second semiconductor optical amplifier; 4. a first wavelength division multiplexer; 5. a second wavelength division multiplexer; 6. a second 3dB coupler; 7. a third semiconductor optical amplifier; 8. A circulator; 9. a 1 × 3 coupler; 10. a first delay fiber; 11. a second delay fiber; 12. an optical clock; 13. an optical D flip-flop.

Fig. 2 shows a boolean chaotic optical signal input to the data terminal of the optical D flip-flop.

FIG. 3 shows an output pattern when the frequency of the external input clock is 10 GHz.

Detailed Description

The first detection optical signal and the second detection optical signal have different wavelengths.

The first delay fiber 10 and the second delay fiber 11 are not of the same length.

The power of the first detection optical signal and the power of the second detection optical signal are not more than 1 mW.

The time difference of the two paths of delay optical fibers is less than the carrier recovery time of the semiconductor optical amplifier.

As shown in fig. 1, continuous light with power of 0.5mW and wavelength of 1550nm is used as first detection signal light, which is input from the a end and divided into two paths by the first 3dB coupler 1, and the upper path enters the second 3dB coupler 6 by the first semiconductor optical amplifier 2 and the first wavelength division multiplexer 4; the lower path enters a second 3dB coupler 6 through a second semiconductor optical amplifier 3 and a second wavelength division multiplexer 5. The first 3dB coupler 1, the first semiconductor optical amplifier 2, the second semiconductor optical amplifier 3, the first wavelength division multiplexer 4, the second wavelength division multiplexer 5 and the second 3dB coupler 6 form an SOA-MZI. Under the condition that no high-power feedback signal is injected into the first semiconductor optical amplifier 2 and the second semiconductor optical amplifier 3 to consume the current carriers of the first semiconductor optical amplifier and the second semiconductor optical amplifier, two beams of continuous light undergo the same gain and phase change, so the interference is cancelled, and the output signal passes through the circulator 8 to the third semiconductor optical amplifier 7 without consuming the current carriers of the third semiconductor optical amplifier. Continuous light with the power of 0.5mW and the wavelength of 1554nm is input into a port B to serve as a second detection light signal, the high-power continuous light is output through a third semiconductor optical amplifier 7 and is divided into three paths through a circulator 8 and a 1 x 3 coupler 9, and one path of the high-power continuous light is fed back to the second semiconductor optical amplifier 3 through a first delay optical fiber 10 and a second wavelength division multiplexer 5; one path is fed back to the first semiconductor optical amplifier 2 through the second delay optical fiber 11 and the first wavelength division multiplexer 4.

It should be noted here that the lengths of the first delay fiber 10 and the second delay fiber 11 are not uniform. Therefore, the time of the two feedback signals reaching the first semiconductor optical amplifier 2 and the second semiconductor optical amplifier 3 is different, the upper arm detection signal and the lower arm detection signal experience different phase differences, so that the interference of the second 3dB coupler 6 is long, the output signal passes through the circulator 8 to the third semiconductor optical amplifier 7, and a large amount of current carriers are consumed. The second probe optical signal input at the B port is led to output low-power continuous light through the third semiconductor optical amplifier 7, and then divided into three paths through the 1 × 3 coupler 9, wherein two paths are used as feedback, and the other path is connected to the data input end of the optical D flip-flop 13.

Since the delay difference between the first delay fiber 10 and the second delay fiber 11 is smaller than the carrier recovery time of the SOA (third semiconductor optical amplifier) used, so that the SOA gain recovery is incomplete, and the SOA-MZI interferes to output an abnormal signal. The process is sequentially cycled, and the chaotic light signal is output at the 1 × 3 coupler 9, as shown in fig. 2. And then, the optical D flip-flop outputs an optical random code with the same speed as the optical clock at the trigger of the 10GHz optical clock, as shown in FIG. 3.

The transmission equation of the SOA-MZI can be expressed as:T _MZI = [P _SOA2 +P _SOA3 -2(P _SOA2 P _SOA3 )^1/2 cos(Φ _SOA2 -Φ _SOA3 )]/4. Here, theP _SOA2 、P _SOA3 、Φ _SOA2 、Φ _SOA3 Respectively representing the power and phase changes of the upper and lower detection signals caused by the first semiconductor optical amplifier 2 and the second semiconductor optical amplifier 3;T _MZI the meaning of (A) is: the output power of the probe optical signal passing through the SOA-MZI and the formula in which the phase and power change.

When the first semiconductor optical amplifier 2 and the second semiconductor optical amplifier 3 do not have external feedback light to be injected, only the upper path and the lower path of detection signals are amplified, the phase difference is not influenced, the SOA-MZI interference is cancelled, and the output signals enter the third semiconductor optical amplifier 7. At this time, the second probe optical signal reversely input from the B port is subjected to cross gain modulation in the third semiconductor optical amplifier 7, and two paths of high-power signals are fed back through the circulator 8 and the 1 × 3 coupler.

When only one path of external high-power feedback light is injected into the first semiconductor optical amplifier 2 and the second semiconductor optical amplifier 3, the high-power feedback light is injected into the path to perform cross phase modulation on the detection signal, the high-power feedback light is not injected into the path to perform amplification on the detection signal, and two paths are generated "π"the SOA-MZI interference is constructive, and the output signal enters the third semiconductor optical amplifier 7. At this time, the second detection signal reversely input from the B port is subjected to cross gain modulation in the third semiconductor optical amplifier 7, and two low-power signals are fed back through the circulator 8 and the 1 × 3 coupler.

When the first semiconductor optical amplifier 2 and the second semiconductor optical amplifier 3 both have external high-power feedback light to inject, the same cross phase modulation effect is only carried out on the two paths of detection signals, the two paths have no phase difference, the SOA-MZI interference is cancelled, and the output signals enter the third semiconductor optical amplifier 7. At this time, the second probe optical signal reversely input from the B port is subjected to cross gain modulation in the third semiconductor optical amplifier 7, and two paths of high-power signals are fed back through the circulator 8 and the 1 × 3 coupler.

Since the delay difference between the first delay fiber 10 and the second delay fiber 11 is smaller than the carrier recovery time of the SOA (third semiconductor optical amplifier) used, so that the SOA gain recovery is incomplete and the SOA-MZI interferes to output an abnormal signal. The process is circulated in sequence, and then the chaotic optical signal is output from the 1 × 3 coupler 9, and then the chaotic optical signal passes through the optical D trigger, and under the trigger of the optical clock, the optical random code with the same speed as the optical clock is output from the C port.