基于振荡器的真随机数发生器的研究

以基于振荡器的真随机数发生器为研究对象,理论分析了影响随机数发生器输出随机性的关键因素.对影响随机性的因素给出不同的参数选取,并使用Matlab软件对各种条件下输出序列的0/1概率差进行了计算,分别验证了采样时刻、高频占空比等因素对真随机数发生器输出的影响,给出了能够提高基于振荡器采样的真随机数发生器随机性的具体方法.所得的结论对设计一个具体的基于振荡器的真随机数发生器具有明确的指导意义.     

应用于UHF RFID标签的低功耗真随机数发生器

设计了一种基于振荡采样法的真随机数发生器.针对UHF RFID标签芯片功耗低、面积小的特点,利用简单有效的电路结构增强发生器的随机性.采用频率受控的被采样数据振荡器与采样时钟异或后形成初步随机数,并增加异或链输出负反馈结构,有效提高了输出序列中"0""1"分布的均匀性,降低了序列的自相关性.标签采用SMIC 0.18μm RF CMOS工艺设计并流片,采样时钟为2MHz,总工作电流少于2μA.     

一种基于噪声的真随机数发生器的ASIC设计与实现

提出了一种应用于密码系统的硬件随机数发生器的ASIC实现,即通过振荡采样把相位噪声转变为随机数.为了使输出平稳,在输出级设计了异或链和伪随机网络.理论研究和仿真测试证明,该方案能生成分布均匀、彼此独立的随机信号.经制版流片后,芯片在1 MHz时钟下输出满足随机性测试的串行随机数.     

一种基于混沌原理的真随机数发生器

选取一维分段线性混沌映射函数设计真随机数发生器的随机源,具体分析了函数中各参数对输出序列随机性和电路稳定性的影响.通过改进函数在混沌吸引盆外的映射关系,成功解决了真随机源电路在各种噪声干扰和器件失配影响下所可能存在的失效问题,显著提高了电路的稳定性.该混沌函数以电压作为迭代变量,电路采用了负反馈形式的运放、采样保持电路和逻辑判断电路等模块,并运用了电荷再分配技术.以该随机源构成的真随机数发生器不但具有理想的随机性,在1M bit/s的输出速率下,平均功耗不超过0.3mW,可广泛应用在SoC等嵌入式环境中.     

新型振荡采样随机源电路与快速仿真

基于对振荡电路的研究,设计实现了一种振荡采样随机源电路。该电路结构中采用了由组合逻辑电路与复杂反馈回路相结合实现的新型快速振荡器,相较于传统的环形振荡器在保留容易实现、受环境影响小等特点的同时,还有提高随机位产生速率、增强随机性等优势。为实现电路的快速仿真,利用MATLAB/Simulink建立了该随机源的模型,并且为提高仿真准确性,建模过程中考虑了CMOS中的主要噪声,引入噪声模型。最后对系统进行仿真测试,结果表明该模型的输出序列具有较好的随机性。     

随机数发生器检测与设计

随机数常作为密钥、初始化向量或密码协议中的时变参数,在密码应用中起到非常重要的作用。根据密码应用对随机性的要求,随机数生成器的输出序列必须满足随机性和不可预测性要求。文中分析了随机数生成器和伪随机数生成器两种生成器模型,给出了常用的随机性检测方法,以及可能的安全攻击方法,最后提出了一种随机性检测新方法。该方法基于输出样本的每比特的信息熵估计,可用于随机数发生器设计过程中的随机性评估。     

一种基于单电子隧穿结和MOS晶体管的混合随机数发生器

提出了一种新颖的单电子随机数发生器(RNG).该随机数发生器由多个单电子隧穿结(MTJ)以及单电子晶体管(SET)/MOS管混合输出电路组成.MTJ被用于实现一个高频率的振荡器.它利用了电子隧穿的物理随机性得到了很大的振荡频率漂移.SET/MOS管输出电路放大并输出MTJ振荡器的输出信号.该信号经过一个低频信号采样后,产生随机数序列.所提出的随机数发生器使用简单的电路结构产生了高质量的随机数序列.它具有简单的结构,输出随机数的速度可以高达1GHz.同时,该电路还具有带负载能力以及很低的功耗.这种新颖的随机数发生器对未来的密码和通讯系统具有一定的应用前景.     

一种基于单电子隧穿结和MOS晶体管的混合随机数发生器

提出了一种新颖的单电子随机数发生器(RNG).该随机数发生器由多个单电子隧穿结(MTJ)以及单电子晶体管(SET)/MOS管混合输出电路组成.MTJ被用于实现一个高频率的振荡器.它利用了电子隧穿的物理随机性得到了很大的振荡频率漂移.SET/MOS管输出电路放大并输出MTJ振荡器的输出信号.该信号经过一个低频信号采样后,产生随机数序列.所提出的随机数发生器使用简单的电路结构产生了高质量的随机数序列.它具有简单的结构,输出随机数的速度可以高达1GHz.同时,该电路还具有带负载能力以及很低的功耗.这种新颖的随机数发生器对未来的密码和通讯系统具有一定的应用前景.     

基于改进RRT-Connect的协同航迹规划

提出一种基于改进双向快速扩展随机树(RRT-Connect)算法的无人机协同航迹规划方法.首先针对基本RRT-Connect算法效率较低且采样具有随机性的缺陷,提出一种改进RRT-Connect算法,通过控制采样范围、引入目标引力来降低无效采样,加快算法的收敛性;利用混沌序列来保证采样节点一定的随机性.利用改进RRT-Connect算法考虑航迹规划模型的约束条件,并引入人工势场,提出一种协同航迹规划方法.通过仿真实验验证了改进RRT-Connect算法与基本RRT-Connect算法相比性能的优越性,以及协同航迹规划方法的有效性.     

基于信号传输理论的Glitch物理不可克隆函数电路设计

通过对信号传输理论、竞争-冒险现象和物理不可克隆函数(Physical Unclonable Functions, PUF)电路的研究,论文提出一种基于信号传输理论的毛刺型物理不可克隆函数电路(Glitch Physical Unclonable Functions, Glitch-PUF)方案。该方案首先根据偏差延迟的信号传输理论,推导出获得稳定毛刺输出的电路级数;然后利用组合逻辑电路的传播延迟差异,结合1冒险和0冒险获得具有毛刺的输出波形,采用多级延迟采样电路实现Glitch-PUF的输出响应。由于毛刺信号具有显著的非线性特性,将其应用于PUF电路可有效解决模型攻击等问题。最后在TSMC 65 nm CMOS工艺下,设计128位数据输出的电路结构,Monte Carlo仿真结果表明Glitch-PUF电路具有良好的随机性。     

On a Scrambling Property of Feedback Shift Registers

A scrambling property of binary feedback shift registers is investigated. When the input sequence has a certain defined randomness, the output symbols are uncorrelated everywhere, except possibly at symbol separations that are integer multiples of the exponent of the feedback polynomial. At those points the output autocorrelation is shown to be equal to higher order moments of the input sequence.     

一种基于神经网络的混沌序列产生方法

应用具有全局最优的ＢＰ改进算法,建立了产生混沌序列的神经网络模型（ＣＧＮＮ）。该模型产生序列随机性良好,序列更换调整容易。对ＣＧＮＮ系统的抗破译性能进行了分析,结果表明,该模型产生的混沌序列确可以作为最优加密密匙及扩频码。     

Logistic chaotic sequence generator based on physical unclonable function

Logistic nonlinear chaotic system has many good characters such as initial value sensitivity and topological mixing in the some parameter condition,which is used to create the random sequence signal generator.Because of the attributions of randomness and uniqueness even under the exact,the same circuit layouts and manufacturing procedures,there is still an instinct unclonable difference in each integrated circuit.Therefore,a new sequence stream generator was proposed based on Logistic chaotic system and physical unclonable function designed by double output look-up-table (LUT).The output of the Logistic sequence generator was associated with a specific physical circuit.This kind of sequence generator could resist an attack such as the replication of the keys of the system.The system was designed and tested on the Xilinx FPGA board.The results show that the same architecture of the circuit and the same config file operated on the different FPGA developing board can generate the total different random chaotic sequence stream and improve the randomness of the stream.     

Extension of an entropy property for binary input memorylesssymmetric channels

The channel output entropy property introduced by A.D. Wyner and J. Ziv (ibid., vol.IT-19, p.769-762, Nov.1973) for a binary symmetric channel is extended to arbitrary memoryless symmetric channels with binary inputs and discrete or continuous outputs. This yields lower bounds on the achievable information rates of these channels under constrained binary inputs. Using the interpretation of entropy as a measure of order and randomness, the authors deduce that output sequences of memoryless symmetric channels induced by binary inputs are of a higher degree of randomness if the redundancy of the input binary sequence is spread in memory rather than in one-dimensional asymmetry. It is of interest to characterize the general class of schemes for which this interpretation holds     

一种超混沌PN序列的设计与实现

为了产生性能良好的伪噪声（PN）序列,基于一个新的超混沌系统,文中提出了一种超混沌PN序列的设计与实现方法,在对连续超混沌系统离散、量化的基础上,利用FPGA芯片实现了这种超混沌PN序列。通过一个串口通信模块电路采集了输出序列的全部样本并进行了序列性能分析,分析表明这种超混沌PN序列具有优良的随机特性和自相关特性,可用于扩频通信和信息加密之中。     

基于压控振荡器的真随机数发生器设计

通过对频率抖动机理的研究,提出一种基于压控振荡器（Voltage-Controlled Oscillator,VCO）的真随机数发生器（True Random Number Generator,TRNG）设计方案.该方案将电阻热噪声放大后作为VCO的控制信号使其振荡频率在中心频率附近随机抖动.VCO所产生的慢振荡信号对周期固定的快振荡信号采样生成原始随机序列,然后利用后处理电路提高序列均匀性并消除自相关性.通过热噪声发生器调节VCO的中心频率可实现序列比特率和随机性之间的权衡.所提电路采用SMIC 55nm CMOS工艺设计,芯片面积0.0124mm²,比特率10Mbps,平均功率0.81mW.输出的随机序列通过NIST SP 800-22测试.     

Resolvability theory for the multiple-access channel

We study the randomness needed for approximating the output distribution of a multiple-access channel, where the original input processes are independent of each other. The approximation is achieved by simulating (possibly alternative) input processes at each of the entries, where the sources of randomness available for the simulators are independent of each other, and the simulators do not cooperate. The resolvability region of a multiple-access channel is defined as the set of all random-bit rate pairs at which accurate output approximation is possible, where the simulation accuracy is measured by the variational distance between finite-dimensional output distributions. Inner and outer bounds on the resolvability region are derived, and close relations between the concepts of resolvability region and capacity region are demonstrated     

Universal discrete denoising: known channel

A discrete denoising algorithm estimates the input sequence to a discrete memoryless channel (DMC) based on the observation of the entire output sequence. For the case in which the DMC is known and the quality of the reconstruction is evaluated with a given single-letter fidelity criterion, we propose a discrete denoising algorithm that does not assume knowledge of statistical properties of the input sequence. Yet, the algorithm is universal in the sense of asymptotically performing as well as the optimum denoiser that knows the input sequence distribution, which is only assumed to be stationary. Moreover, the algorithm is universal also in a semi-stochastic setting, in which the input is an individual sequence, and the randomness is due solely to the channel noise. The proposed denoising algorithm is practical, requiring a linear number of register-level operations and sublinear working storage size relative to the input data length.     

True Random Number Generator With a Metastability-Based Quality Control

We present a metastability-based true random number generator that achieves high entropy and passes NIST randomness tests. The generator grades the probability of randomness regardless of the output bit value by measuring the metastable resolution time. The system determines the original random noise level at the time of metastability and tunes itself to achieve a high probability of randomness. Dynamic control enables the system to respond to deterministic noise and a qualifier module grades the individual metastable events to produce a high-entropy random bit-stream. The grading module allows the user to trade off output bit-rate with the quality of the bit-stream. A fully integrated true random number generator was fabricated in a 0.13 mum bulk CMOS technology with an area of 0.145 mm².     

一种混合混沌序列的研究

针对单一混沌映射产生的序列复杂度比较低的缺点,提出一种新的混合混沌序列产生方法。该方法主要是通过组合不同的混沌映射并且扰动混沌映射中的参数来产生混沌序列。对产生的序列进行了平衡性、随机性和相关性等分析,并将该序列作为扩频码用于直接序列扩频系统中进行仿真。仿真结果表明,这种混合混沌序列有较好的平衡性、随机性和相关性,证明了该序列作为扩频码的可行性。