忆感器的Simulink模型及其特性分析

忆感器是一种具有记忆功能的非线性电感器。根据忆感器的数学模型,建立了Simulink仿真模型,并由该模型的仿真结果得到关于忆感器的典型特性,验证了模型的有效性。研究了不同参数对忆感器特性的影响。根据该模型,磁控忆感系统的建模也可以采用类似的方法。     

忆阻-电容等效忆感器的有源回转实现及其特性仿真

忆阻器的出现给电子信息技术的进一步发展带来新的契机。忆感器作为新型模拟记忆器件的另一种类型,其实体器件尚待研发。基于模拟记忆器件特性的分析,利用电压模和电流模电路分别进行电抗性质的变换,实现对电容和忆阻回转的忆感器有源等效。MATLAB的系统级仿真结果表明:等效忆感器具有电流-磁通量之间的自收缩滞回特性,这与理论概念上的忆感特性相吻合,为忆感器在电子学中产生新功能的实验研究提供了功能模拟实体。     

基于忆阻器的Simulink模型及其特性分析

忆阻器是纳米级尺寸、非易失性的两端无源性器件,在数据存储、图像处理和模拟神经网络突触等方面有很大的优势。为了研究忆阻器的特性,在理想的忆阻器模型的基础下,搭建了2种不同窗函数的忆阻器Simulink模型。通过Matlab仿真研究了不同的输入激励以及模型的变化对忆阻器的影响,获得了关于忆阻器的许多新特性和一些重要的结果,并与已知的忆容器和忆感器的输入输出特性作了对比,说明忆阻器与忆容器、忆感器具有相似的特性。仿真结果表明忆阻器在应用方面的具有很大的潜力。     

Petri网在电信管理网可信性建模中的应用

介绍了ＴＭＮ（电信管理网）可信性建模的一种新的方法－Ｐｅｔｒｉ网。首先简要介绍了Ｐｅｔｒｉ网的基本概念和Ｐｅｔｒｉ网的特性分析，然后描述了用Ｐｅｔｒｉ网进行建模的一般方法并举例说明了它在ＴＭＮ可信性建模中的应用。最后还介绍了一种自动生成可信性Ｐｅｔｒｉ网模型的方法。     

一种荷控忆容器的电路模拟器设计及其基本特性分析

直接从荷控忆容器的数学模型出发,首先采用通用有源电路芯片设计了忆容器"浮地"电路模拟器,之后结合Matlab和Multisim混合仿真的方法,研究了其二端口的基本电特性,给出了在不同交变信号激励以及不同参数下忆容器电路模拟器的系统级仿真实验,最后完成了其硬件电路的实现及性能测试。结果表明:所设计的荷控忆容器具有电荷-电压之间的自收缩磁滞回线特性,是一种具有记忆特性的非线性电容,这与理论概念上的忆容器特性相吻合,可为忆容器在电子学领域产生新的应用电路提供器件模拟实体。     

忆阻元件的研究进展

忆阻元件是一种联系电荷和磁链之间关系的新的无源电路元件,可以称其为第四类基本电路元件。本文首先介绍了忆阻元件的概念、基本模型及其数学表示方法,然后介绍了目前国内外的研究现状。国内研究主要集中于忆阻元件的数学模性、特性及与其它元件组成的简单电路的性能;国外的研究主要集中于忆阻元件在各方面的潜在应用以及由忆阻概念进一步推测忆容和忆感元件及其系统。     

带有阈值电压的非线性忆容器混合建模与特性分析

忆容器是在电感、电容和电阻基本电路元件之后出现的新型电路元件,因其具有非易失性和非线性特点,在众多领域中具有广泛的应用前景。为了使忆容器模型更接近实际忆容器和方便与其他二端口电路元件连接,通过引入阈值电压的方法改进了忆容器荷控数学模型,并利用Simscape和Simulink相结合的混合建模方法建立了带有阈值电压的忆容器二端口仿真模型。通过仿真实验分析了触发电压的幅值和频率对该仿真模型磁滞回线的影响。结果表明,建立的仿真模型符合忆容器的基本特性,即磁滞回线随电压幅值的增大逐渐变宽,随电压频率的增加逐渐变窄。该模型可为以后忆容器的应用研究和仿真研究奠定基础。     

基于UML的全程建模研究与应用

统一建模语言(Unified Modeling Language, UML)是一种通用的、可视化标准建模语言,是面向对象的系统开发工具之一,它适用于各种软件开发方法、软件生命周期的各个阶段.I2DEF(Integrated IDEF)建模方法又称全程建模方法,它全面支持系统调查、系统分析和设计等各个阶段的建模,实现了软件开发从分析向设计阶段的平稳过渡.对用UML实现全程建模进行了研究,从结构建模、动态建模和功能建模三位一体的角度,提出了一套基于UML的全程建模方法,并通过一个具体的实例应用了上述建模方法,最后把UML与其他描述全程建模的工具进行了分析比较.     

一个磁控忆阻器混沌电路及其FPGA实现

忆阻器是一种新的电路元件.为研究忆阻器混沌的基本特性和实现方法,对一种三次光滑特性忆阻器混沌电路的基本动力学特性进行了深入分析,包括平衡点集及其稳定性,暂态混沌及其状态转移,提出了一种克服暂态混沌从而产生稳定混沌的方法,并基于FPGA研究了忆阻器混沌的数字化实现问题,获得了预期的实验结果.     

简化Markov模型的可靠性分析

Markov模型是电子产品系统可靠性分析中最常使用的方法。但在应用Markov模型的时候一个主要的问题是它的巨大的状态数，使得它对复杂系统的建模和分析变得非常困难。本文提出了一种新的简化Markov模型的方法来简化对系统可靠性的分析。并且对该简化方法的误差界限进行了讨论。数值仿真结果表明了该方法的有效性。     

Mutator-Based Meminductor Emulator for Circuit Applications

A mutator-based meminductor emulator whose inductance can be varied by an external current source is proposed. The implementation of a meminductor emulator is very important, since real meminductors are not physically realizable with current technology. Though there is active research on memristor or memcapacitor emulators, no significant contribution for the meminductor emulator has been presented yet. In this paper, a meminductor emulator has been built using the principle of a mutator, in that a memristor with \(v-i\) at one port functions as a meminductor in the other port, whose input is characterized by \(\varphi - i\) curve. It is shown that multiple meminductor circuits can be built in various configurations with memristors combined with a single mutator. The feasibility of our meminductor emulator and its expandable configurations are verified experimentally and SPICE simulation.     

Study on Time Domain Characteristics of Memristive RLC Series Circuits

The notion of memristive system was first proposed in 2009. This concept of memory element has been extended from memristors \((\hbox {R}_{\mathrm{M}})\) to memcapacitors \((\hbox {C}_{\mathrm{M}})\) and meminductors \((\hbox {L}_{\mathrm{M}})\). Currently, the above elements are not available as off-the-shelf components. Therefore, based on the realization of a light-dependent resistor (LDR), memristor analog model, memcapacitor and meminductor analog circuit models based on \(\hbox {R}_{\mathrm{M}}-\hbox {C}_{\mathrm{M}}\) and \(\hbox {R}_{\mathrm{M}}-\hbox {L}_{\mathrm{M}}\) converters are first introduced. Then, instead of the traditional resistor, capacitor, and inductor, memristor-, memcapacitor-, and meminductor-equivalent circuits are used to determine the time domain characteristics of the RLC-mode circuits with mem-elements. These circuits are discussed in detail, and in particular, the phenomena caused by the memory characteristics of the mem-elements are studied. This research provides an important reference for further research into mem-element applications in circuit theory.     

Meminductor Response Under Periodic Current Excitations

Recently, the mem-elements-based circuits have been addressed frequently in the nonlinear circuit theory due to their unique behavior. Thus, the modeling and characterizing of the mem-elements has become essential, especially studying their response under any excitation signal. This paper investigates the response of the meminductor under DC, sinusoidal, and periodic current signals for the first time. Furthermore, a meminductor emulator is developed to fit the obtained formulas which are built using commercial off the shelf components. The proposed analysis offers closed form expressions for the meminductance for each case. Moreover, many fundamentals and properties are derived to understand the responses such as the maximum saturation time in case of the DC response. A general closed form expression for the meminductance is derived under any periodic waveform, and this formula has been validated by applying a square wave as an example.     

Non-Volatile Memories for Removable Media

NAND Flash memory has become the preferred nonvolatile choice for portable consumer electronic devices. Features such as high density, low cost, and fast write times make NAND perfectly suited for media applications where large files of sequential data need to be loaded into the memory quickly and repeatedly. When compared to a hard disk drive, a limitation of the Flash memory is the finite number of erase/write cycles: most of commercially available NAND products are guaranteed to withstand 10$^{5}$ programming cycles at most. As a consequence, special care (remapping, bad block management algorithms, etc.) has to be taken when hard-drive based, read/write intensive applications, such as operating systems, are migrated to Flash-memory based devices. One of the basic requirements of the consumer market for data storage is the portability of stored data from one device to the other. Flash cards are the actual solution. A Flash card is a nonvolatile “system in package” in which a NAND Flash memory is embedded with a dedicated controller. This paper presents the basic features of the NAND Flash memory and the basic architecture of Flash cards. We provide an outlook on opportunities and challenges of future Flash systems.      

宽带DRFM雷达干扰机信号处理模块设计

给出了宽带数字射频存储器(DRFM)雷达干扰机信号处理模块组成框图以及信号处理流程,描述了模块实现的关键技术,特别是在FPGA中实现高速信号并行处理的方法.该信号处理模块可以提供1 GHz瞬时处理带宽,存储深度达到2 048 μs,可实现对新体制宽带雷达有效干扰,具有广阔的应用前景.     

Low-Power Limited-Search Parallel State Viterbi Decoder Implementation Based on Scarce State Transition

In this paper, a low-power Viterbi decoder design based on scarce state transition (SST) is presented. A low complexity algorithm based on a limited search algorithm, which reduces the average number of the add-compare-select computation of the Viterbi algorithm, is proposed and seamlessly integrated with the SST-based decoder. The new decoding scheme has low overhead and facilitates low-power implementation for high throughput applications. We also propose an uneven-partitioned memory architecture for the trace-back survivor memory unit to reduce the overall memory access power. The new Viterbi decoder is designed and implemented in TSMC 0.18-mum CMOS process. Simulation results show that power consumption is reduced by up to 80% for high throughput wireless systems such as Multiband-OFDM Ultra-wideband applications.     

基于散斑相关的宽视场成像技术研究进展（特邀）

散射成像技术因具备透过生物组织等散射介质后清晰成像的能力而受到广泛关注。近年来,基于散斑自相关的成像方法以其非接触、无需先验信息且能够单帧成像的特点得到迅速发展。然而,散斑自相关成像受光学记忆效应的限制。当多个目标之间的距离在记忆效应范围之外时,基于散斑自相关的成像方法会导致目标自相关信息在相关域发生混叠,导致成像严重退化。文中在光学记忆效应及散斑自相关成像基本原理的基础上,首先介绍了基于散斑自相关和与散斑相关成像有关的其他散射成像技术。接着介绍了拓展光学记忆效应的主要技术及相关应用。最后总结了基于散斑相关的宽视场成像技术目前存在的问题,并对未来的发展应用进行了展望。