关键词: 半导体激光器/
混沌激光/
多位量化/
物理随机数
English Abstract
14-Gb/s physical random numbers generated in real time by using multi-bit quantization of chaotic laser
Wang Long-Sheng1,2,Zhao Tong1,2,
Wang Da-Ming1,2,
Wu Dan-Yu3,
Zhou Lei3,
Wu Jin3,
Liu Xin-Yu3,
Wang An-Bang1,2
1.Key Laboratory of Advanced Transducers and Intelligent Control System, Ministry of Education, Taiyuan University of Technology, Taiyuan 030024, China;
2.Institute of Optoelectronic Engineering, College of Physics and Optoelectronics, Taiyuan University of Technology, Taiyuan 030024, China;
3.Microwave Devices and Integrated Circuit Laboratory, Institute of Microelectronics of Chinese Academy of Sciences, Beijing 100029, China
Fund Project:Project supported by the National Nature Science Foundation of China (Grant Nos. 61475111, 61671316), the Natural Science Foundation for Excellent Young Scientists of Shanxi, China (Grant No. 2015021004), the International Science and Technology Cooperation Program of Shanxi Province, China (Grant No. 201603D421008), and the International Science and Technology Cooperation Program of China (Grant No. 2014DFA50870).Received Date:12 July 2017
Accepted Date:04 August 2017
Published Online:05 December 2017
Abstract:Real-time high-speed physical random numbers are crucial for a broad spectrum of applications in cryptography, communications as well as numerical computations and simulations.Chaotic laser is promising to construct high-speed physical random numbers in real time benefitting from its complex nonlinear dynamics.However,the real-time generation rate of physical random numbers by using single-bit extraction is confronted with a bottleneck because of the bandwidth limitation caused by laser relaxation,which dominates the laser chaos and then limits the effective bandwidth only to a few GHz.Although some bandwidth-enhanced methods have been proposed to increase the single-bit generation rate, the potential is very limited,and meanwhile the defects of system complexity will be introduced.An alternative method is to construct high-speed physical random numbers by using the multi-bit extraction.In this method,each sampling point is converted to N digital bits by using multi-bit analog-to-digital converter (ADC) and their M(M 6 N) least significant bits are retained as an output of random bits,where N and M are the numbers of ADC bits and retained bits,respectively.The generation rate of random numbers is thus equal to M times sampling rate and can be greatly increased.Whereas,in the multi-bit extraction demonstrations,the intensity output of chaotic laser is usually digitized by the commercial oscilloscope and then processed with least-significant-bit retention followed by other postprocessing methods such as derivative,exclusive-OR,and bit-order reversal.These followed post-processing operations have to be implemented off-line and thus cannot support the real-time generation of random numbers.Resultantly,it is still an ongoing challenge to develop high-speed generation schemes of physical random numbers with the capability of real-time output.In this paper,a real-time high-speed generation method of physical random numbers by using multi-bit quantization of chaotic laser is proposed and demonstrated experimentally.In the proposed generation scheme,an external-cavity feedback semiconductor laser is utilized as a source of chaotic laser.Through quantizing the chaotic laser with 6-bit ADC, which is triggered by a clock at a sampling rate of 7 GHz,a binary sequence with six significant bits can be achieved. After the selection of the two least-significant bits and self-delayed exclusive-OR operation in the field-programmable gate array (FPGA),a real-time 14-Gb/s binary stream is finally achieved.This binary stream has good uniformity and independence,and has passed the industry-standard statistical test suite provided by the National Institute of Standards and Technology (NIST),showing a good statistical randomness.It is believed that this work provides an alternative method of generating the real-time high-speed random numbers and promotes its applications in the field of information security.
Keywords: semiconductor laser/
laser chaos/
multi-bit quantization/
physical random number
