阅读说明：本技术 一种基于反馈干涉原理产生混沌光方法 (Method for generating chaotic light based on feedback interference principle ) 是由 王云才 张国栋 张建国 李璞 王安帮 李才 于 2019-10-31 设计创作，主要内容包括：本发明涉及混沌信号领域,具体为一种基于反馈干涉原理产生混沌光方法。本发明提出一种基于反馈干涉原理产生混沌光方法,该方法区别于利用半导体光器通过光注入、光反馈、光电反馈等扰动方式产生混沌光的传统方法,是一种混沌光产生新方法,能够有效消除传统扰动方式对混沌光系统的安全威胁,大大提高了混沌系统的抗扰能力。该混沌光作为一种相位混沌信号,为后期实现高速的采集量化过程提供可能和依据。而且,本发明可以通过调试和优化,产生宽频谱、高熵值的混沌光信号,在高速真随机密钥、混沌光时域反射仪、混沌超宽带脉冲信号产生、相干长度可调谐光源等领域具有重要意义。(The invention relates to the field of chaotic signals, in particular to a method for generating chaotic light based on a feedback interference principle. The invention provides a method for generating chaotic light based on a feedback interference principle, which is different from the traditional method for generating the chaotic light by using a semiconductor optical device through disturbance modes such as light injection, light feedback, photoelectric feedback and the like, is a novel chaotic light generation method, can effectively eliminate the safety threat of the traditional disturbance mode to a chaotic optical system, and greatly improves the anti-interference capability of the chaotic system. The chaotic light is used as a phase chaotic signal, and provides possibility and basis for realizing a high-speed acquisition and quantization process in the later period. Moreover, the invention can generate wide-spectrum and high-entropy chaotic light signals through debugging and optimization, and has important significance in the fields of high-speed true random keys, chaotic light time domain reflectometers, chaotic ultra-wideband pulse signal generation, coherent length tunable light sources and the like.)

1. A method for generating chaotic light based on a feedback interference principle is characterized in that a first detection light signal is divided into two paths, and the two paths of detection light signals are respectively input into a first annular light path and a second annular light path after being subjected to cross gain modulation and cross phase modulation according to the strength and the time delay of the feedback light signal under initial conditions; according to the phase states of the two paths of detection optical signals, the optical signals output by the first annular optical path and the second annular optical path are subjected to interference cancellation or interference constructive action and then input to a third annular optical path; the second detection optical signal is input to a reflection port of a third annular optical path after being acted by the cross gain modulation principle of a third semiconductor optical amplifier (9); the signal light output by the third annular light path is divided into three paths of optical signals, 1 path of optical signal is finally output, 2 paths of optical signals are used as feedback signals and respectively act on the first annular light path and the second annular light path after optical time delay operation, the two paths of feedback optical time delays are unequal through adjustment and cannot simultaneously reach the first annular light path and the second annular light path, and the two paths of first detection optical signals respectively perform cross gain modulation and cross phase modulation according to the strength and the time delay of the feedback optical signals at that time and are input into the first annular light path and the second annular light path; the process is circulated in sequence, and the output optical signal can generate periodic oscillation; by further adjusting that the feedback delay difference is smaller than the carrier recovery time of the third semiconductor optical amplifier (9), abnormal pulses occur in the carrier recovery time of the third semiconductor optical amplifier (9), so that uncertain optical signals are output and are repeated in sequence, and finally the output optical signals are subjected to random oscillation to generate broadband chaotic light with binary change of amplitude and random change of phase.

2. The method of claim 1, wherein the first and second detection optical signals have different wavelengths.

3. The method of claim 1, wherein the powers of the first and second detecting light signals are not more than 1 mW.

4. The method for generating the chaotic light based on the feedback interference principle as claimed in claim 1, wherein the two feedback loops respectively realize the time delay through the first optical delay line (10) and the second optical delay line (12), and the two optical delay lines have different lengths.

Technical Field

The invention relates to the field of chaotic signals, in particular to a method for generating chaotic light based on a feedback interference principle.

Background

In recent years, due to the characteristics of noise-like and wide spectrum of chaotic light signals, the chaotic light signal has a wide application prospect in the fields of high-speed true random keys, chaotic light time domain reflectometers, chaotic ultra-wideband pulse signal generation, coherent length tunable light sources and the like, and has received wide attention of researchers.

The conventional chaotic light generation method is obtained by using a semiconductor laser (a distributed feedback laser DFB, a vertical cavity surface emitting laser VECSEL) and the like through disturbance modes such as optical feedback, optical injection or photoelectric feedback.

However, no matter the distributed feedback laser or the vertical cavity surface emitting laser, the quality of a transverse mode of a light spot of an output optical signal is poor, so that the difficulty in subsequent application is increased; moreover, the chaotic intensity oscillation of a semiconductor laser is typically affected by the relaxation oscillation frequency of the laser. Through frequency domain analysis, the power spectrum distribution has obvious peaks at the relaxation oscillation frequency, so that the effective bandwidth is limited; in addition, the chaotic light signal generated by the external disturbance mode can cause a plurality of adverse factors, such as time delay characteristic introduced by external cavity feedback, and can cause the output signal to present weak periodicity, so that the anti-interference capability of the system can be reduced by further extracting and analyzing the time delay information, and the safety of the whole chaotic light system can be threatened.

In consideration of the technical problems that the effective bandwidth is limited and the anti-interference capability of the system is reduced due to the fact that the chaotic light signal is generated in the traditional disturbance mode, the method for generating the chaotic light based on the feedback interference principle has great significance.

Disclosure of Invention

The invention provides a method for generating chaotic light based on a feedback interference principle, which aims to solve the technical problem caused by generating chaotic light signals by using a traditional disturbance mode.

The invention is realized by adopting the following technical scheme: a method for generating chaotic light based on a feedback interference principle comprises the steps that a first detection light signal is divided into two paths, and the two paths of detection light signals are subjected to cross gain modulation and cross phase modulation according to the strength and the time delay of the feedback light signal under initial conditions and input into a first annular light path and a second annular light path; according to the phase states of the two paths of detection optical signals, the optical signals output by the first annular optical path and the second annular optical path are subjected to interference cancellation or interference constructive action and then input to a third annular optical path; the second detection optical signal is input to a reflection port of a third annular optical path after being acted by a cross gain modulation principle of a third semiconductor optical amplifier; the signal light output by the third annular light path is divided into three paths of optical signals, 1 path of optical signal is finally output, 2 paths of optical signals are used as feedback signals and respectively act on the first annular light path and the second annular light path after optical time delay operation, the two paths of feedback optical time delays are unequal through adjustment and cannot simultaneously reach the first annular light path and the second annular light path, and the two paths of first detection optical signals respectively perform cross gain modulation and cross phase modulation according to the strength and the time delay of the feedback optical signals at that time and are input into the first annular light path and the second annular light path; the process is circulated in sequence, and the output optical signal can generate periodic oscillation; by further adjusting that the feedback delay difference is smaller than the third semiconductor optical amplifier carrier recovery time, abnormal pulses occur in the third semiconductor optical amplifier carrier recovery time, so that uncertain optical signals are output and are repeated in sequence, and finally the output optical signals generate random oscillation, and broadband chaotic light with binary change of amplitude and random change of phase is generated.

The invention provides a method for generating chaotic light based on a feedback interference principle, which is different from the traditional method for generating the chaotic light by using a semiconductor optical device through disturbance modes such as light injection, light feedback, photoelectric feedback and the like, is a novel chaotic light generation method, can effectively eliminate the safety threat of the traditional disturbance mode to a chaotic optical system, and greatly improves the anti-interference capability of the chaotic system.

The chaotic light is used as a phase chaotic signal, and provides possibility and basis for realizing a high-speed acquisition and quantization process in the later period.

Moreover, the invention can generate wide-spectrum and high-entropy chaotic light signals through debugging and optimization, and has important significance in the fields of high-speed true random keys, chaotic light time domain reflectometers, chaotic ultra-wideband pulse signal generation, coherent length tunable light sources and the like.

Drawings

Fig. 1 is a schematic structural diagram of a method for generating chaotic light based on the feedback interference principle.

1-first semiconductor laser, 2-first 3dB coupler, 3-first semiconductor optical amplifier, 4-second semiconductor optical amplifier, 5-first circulator, 6-second circulator, 7-second 3dB coupler, 8-second semiconductor laser, 9-third semiconductor optical amplifier, 10-first optical delay line, 11-third circulator, 12-second optical delay line, 13-1 × 3 coupler.

Detailed Description

As shown in fig. 1, the present invention provides a method for generating chaotic light based on the feedback interference principle, the apparatus includes: a semiconductor laser, a circulator, a 3dB coupler, a Semiconductor Optical Amplifier (SOA), an optical delay line, and a 1 × 3 coupler. The specific connection mode is as follows: the first probe optical signal λ is detected by the first semiconductor laser 1^/Injected into the input of the first 3dB coupler 2; the first 3dB coupler 2 is divided into two paths to output and is respectively connected with a first semiconductor optical amplifier 3, a first circulator 5, a second semiconductor optical amplifier 4 and a second circulator 6 in sequence; the outputs of the two couplers are connected to the input end of a second 3dB coupler 7, and the output end of the second 3dB coupler 7 is connected to the input end of a third circulator 11; a second probe optical signal lambda is detected by a second semiconductor laser 2^//Injecting a third semiconductor optical amplifier 9, wherein the output end of the third semiconductor optical amplifier 9 is also connected to the input end of the third circulator 11; the output end of the third circulator 11 is connected to the input end of the 1 × 3 coupler 13, the output of the 1 × 3 coupler 13 is divided into 3 paths, and the two paths are used as feedback optical signals and are respectively connected with the first optical delay line 10, the first circulator 5 and the second optical delay line in sequenceWire 12, first circulator 6; the other 1 path is used as the final output of the chaotic optical signal.

The specific working process is as follows: the first probe optical signal λ is detected by the first semiconductor laser 1^/Injecting the mixture into the input end of the first 3dB coupler 2, and outputting the mixture in two paths through the first 3dB coupler 2; first probe light λ^/The light enters a second 3dB coupler 7 through a first semiconductor optical amplifier 3 and a first circulator 5 in sequence; similarly, the first probe optical signal λ^/Enters the second 3dB coupler 7 through the second semiconductor optical amplifier 4 and the second circulator 6 in this order. Because the system is in an initial state, both the two feedback loops have no optical signal input, SOA carriers are not consumed in the process, and the first detection optical signal lambda is^/Under the condition of same gain, the first semiconductor optical amplifier 3 and the second semiconductor optical amplifier 4 respectively output high power through the first circulator 5 and the second circulator 6; because the feedback optical signals are the same, the two paths of probe light generate the same phase change through the SOA, and according to the cross phase modulation principle, the optical signals are subjected to interference cancellation in the second 3dB coupler 7 through the first circulator 5 and the second circulator 6, and the output is low power; from the first probe optical signal λ^/The second probe optical signal lambda is fed to the third semiconductor optical amplifier 9 via the third circulator 11 without consuming charge carriers, and is fed to the second semiconductor laser 8^//Injecting the signal into a third semiconductor optical amplifier 9 to generate a cross gain modulation effect, and outputting an optical signal opposite to the input, namely high power; then 3 paths of optical signals are generated by the 1 × 3 coupler 13, 1 path of optical signals is used as final output, and 2 paths of optical signals are used as feedback signals and are respectively acted on the first circulator 5 and the second circulator 6 through the first optical delay line 10 and the second optical delay line 12.

Because the feedback light time delays are unequal, the output light signals are high power and cannot reach the first circulator 5 and the second circulator 6 simultaneously through the first light delay line 10 and the second light delay line 12 respectively; if the output optical signal reaches the first circulator 5 through the first optical delay line 10, the first semiconductor optical amplifier 3 consumes the carriers and the output is low power through the first circulator 5; the second circulator 6 does not consume the current carrier of the second semiconductor optical amplifier 4 because no feedback optical signal is input at this time, and the output is high power through the second circulator 6; because the two feedback signals are inconsistent, the two detection light beams generate pi phase difference through the SOA, and are subjected to interference and constructive through the second 3dB coupler 7, and the output is high power; similarly, the output of the final 1 × 3 coupler 13 is low power, and the optical signal is fed back to the first circulator 5 and the second circulator 6 through the first optical delay line 10 and the second optical delay line 12. The process is circulated in sequence, and the output optical signal can generate periodic oscillation; when the feedback delay difference is further adjusted to be smaller than the SOA carrier recovery time, abnormal pulses occur in the SOA carrier recovery time, so that uncertain optical signals are output, and the output is repeated in sequence, and the optical signals are found to have random oscillation, so that broadband chaotic light with binary change of amplitude (high and low power) and random change of phase is generated.

In addition, the characteristics of the frequency spectrum, the amplitude and the like of the chaotic light signal can be controlled and optimized by further adjusting parameters such as feedback delay, the working rate of the node and the like until an optimal working interval generated by the chaotic light is found, so that the chaotic light signal with wide frequency spectrum and high entropy can be generated.