Efficient and Simple Method for Designing Chaotic S‐Boxes

A substitution box (S‐box) plays a central role in cryptographic algorithms. In this paper, an efficient method for designing S‐boxes based on chaotic maps is proposed. The proposed method is based on the mixing property of piecewise linear chaotic maps. The S‐box so constructed has very low differential and linear approximation probabilities. The proposed S‐box is more secure against differential and linear cryptanalysis compared to recently proposed chaotic S‐boxes.     

一种高效模（2n-2p）乘法器的设计

结合两类修正方法,提出了一种高效的模（2n -2p ）乘法器（n≥2 p）的实现方法。与文献[1]中设计比较,本文乘法器结构上少了一级加法,并且综合结果也显示平均面积和延迟分别有10％和13％的减小。     

DPBD—设计一类强NP—Complete问题近似算法的有效方法

本文针对一类强NP-Complete问题近似算法的设计问题,提出一种通用的设计策略DPBD,它通过一局部近似算法而获得一全局近似算法,并保证精度在一定范围内.最后,本文将DPBD应用于一著名的NP难度问题:平面Covering问题,对方法的有效性给予了证实.     

Efficient Design of Rounding Based Static Segment Imprecise Multipliers for Error Tolerance Application

Journal of Electronic Testing - Error-Tolerant applications regularly accomplish more data adaption. Approximate computing is one of the optimum strategies for data manipulation in several...     

如何设计安全、有效的信号继电器

高档的通信设备曾一度只能在办公环境中才能使用,然而现在这种情况已经改变,家庭中已经普遍具备了互连能力,许多家用电子设备现在通过Ipv6和其他技术已经具备了上网能力。随着宽带通信应用的增加,调制解调器、各种DSL接入复用器以及其他类似设备的安装已经遍及办公室和家庭,消费者可以方便获得价廉的通信设备。对于设备制造商来说,这些装置必须满足安全标准,如IEC60950(InternationalElectrotechnicalCommission第三版),它要求在与数据通信线连接的设备上实现电话网络高压电路的隔离。一般情况下,人们采用传统的电磁通信继电器来开关内…     

设计高效能的手持设备照明解决方案

现今的便携设备不单功能越来越多,而且对功率的需求也越来越大,这对便携电池的电源设计构成很大的挑战.然而,如果对有关应用的能源消耗有更深入的认识,便可设计出更加节能的解决方案,这不单可以延长电池的寿命,而且可以提供更好的用户体验.     

电磁散射的拉格朗日乘子区域分解算法

针对电磁散射问题,提出了一种基于广义变分原理的区域分解算法.将原求解区域划分为若干个不重叠的子区域,引入拉格朗日乘子法以满足相邻子区域之间场的连续性要求,并建立其修正泛函,使原问题转化为求解拉格朗日乘子.研究了子区域系数矩阵的可逆性.为了进一步提高效率,采用了重启的广义最小残量法为求解器.数值算例验证了本文方法的准确性和有效性.     

Multipliers for residue-number-arithmetic digital filters

A recently proposed residue-number-arithmetic digital filter offers major cost and speed advantages over binary-arithmetic digital filters, but suffers one major drawback. The filter coefficients must be constant, since the lack of a fast method of multiplication by a fraction in residue arithmetic requires the coefficients to be realised by a fixed table look-up read-only memory. Two multipliers are proposed which realise a completely general fractional multiply and are suitable for digital-filtering applications.     

基于交替方向乘子法的Capon层析SAR成像方法

合成孔径雷达（Sythetic Aperture Radar, SAR）层析成像（TomoSAR）是一种多基线干涉测量技术,可沿垂直于视线（Perpendicular to the Line?Of?Sight, PLOS）方向估计功率谱图（Power Spectrum Pattern, PSP）即后向散射系数,从而实现三维成像。本文提出一种改进的波束形成优化算法,在双约束鲁棒Capon波束形成算法（Doubly Constrained Robust Capon Beamforming, DCRCB）的基础上,结合L1范数的约束函数,构建交替方向乘子法（Alternating Direction Method of Multipliers, ADMM）的代价函数,将DCRCB恢复的后向散射系数进行进一步稀疏优化,实现层析SAR的三维成像。ADMM算法以增广拉格朗日算法为基础,将较为复杂的全局求解问题转换为两个或多个更易求解的简单局部子问题。ADMM算法在迭代中,各子问题可分别完成稀疏重构和降噪运算,被分离的局部子问题代数式都较为简单,均能较容易地求出确定的解,且不必对其进行收敛运算与约束操作。因此,ADMM算法具有重建精度高的优势。本文采用2021年中国科学院空天信息创新研究院发布的山西运城地区的8通道机载阵列干涉SAR数据进行了实验验证,实验结果验证了算法的有效性。     

基于FTTH的ODN设计方法——上海“城市光网”技术创新和应用实践之三

当前,为适应三网融合、智慧城市、基础宽带网建设等一系列国家信息化发展战略的要求,各电信运营商已全面开展以光纤接入替代原有铜线接入的宽带网络改造工作.其中,ODN是FITH建设和改造中的重点和难点,作为电信运营商,在ODN设计中应该考虑哪些问题以及如何实现标准化ODN的建设方案,是摆在面前的一个重要课题.本文围绕PON技术演进对ODN的要求、ODN覆盖半径、分光方式和分光位置、用户光缆网拓扑结构和交接配线方法、ODN验收测试指标等方面,全面论述了基于FTTH的ODN设计思路和方法.     

一种精确的衍射微透镜设计方法

考虑光线在微透镜衍射层中的实际光程，本文对现有的衍射微透镜设计公式进行了改进，提出一种精确的衍射微透镜设计方法。按照精确的光程差方法和现有方法分别具体设计了微透镜面形。并用衍射叠加积分方法进行了成像质量分析和比较。     

Designing Energy Efficient Strategies Using Markov Decision Process for Crowd-Sensing Applications

Mobile Networks and Applications - In mobile crowd-sensing, smartphone users take part in sensing and then share the data to the server (cloud) and get an incentive. These data can be utilized for...     

一种数字全通滤波器的设计方法研究

研究了一种数字全通滤波器的设计方法.对于一个平稳的全通滤波器,其分母多项式一定具有最小相位.该方法是基于最小相位滤波器的复倒谱系数和其群迟延函数以及其系统函数之间的关系,通过一个非线性的递归方程求解分母多项式的系数.由全通滤波器的特性已知,分母系数可以完全决定全通滤波器的传递函数.仿真结果表明这种方法能够使所设计滤波器的群延迟特性在整个频率范围内以近似理想的群延迟特性存在.并结合实现提出了一种用FIR逼近IIR的方法.     

用查表法实现数控振荡器的ASIC设计

介绍了一种用查表法实现数控振荡器的专用集成电路设计方法,主要部件分为频率控制字寄存器、相位控制字寄存器、累加器、加法器、锁存器等。该电路具有频率分辨率高、频率变化速度快、相位可连续线性变化和生成的正/余弦信号正交特性好等特点,波形发生器存储量大、读取速度快。采用正向全定制设计存储器,嵌入片内集成,并引入流水线结构,设计出高速、高精度的数控振荡器。电路结构简单,可靠性高,该设计采用0.5μm单层多晶三层铝的CMOS工艺成功加工,在数控振荡器的传统设计方法上提高了电路精度和频率。     

应用于非负稀疏信号重构的交替方向乘子法

非负稀疏信号在欠定线性观测条件下的重构效果不理想,仍有进一步提高的余地。文中将非负稀疏信号重构建模为线性规划问题,在交替方向乘子法的框架下得到了具有闭合解形式的优化算法,且算法复杂度较低。为了进一步增强重构信号的稀疏性,提出了迭代加权线性规划算法,通过对权值向量和重构信号交替优化提高了重构准确率。实验仿真验证了算法的有效性,针对随机生成信号和实际语音能量谱这两类非负稀疏信号均取得了较好的重构效果,重构性能优于目前一些流行的稀疏重构算法。      

基于FPGA的数字乘法器性能比较

详细描述了四种基本的FPGA数字乘法器设计方法即阵列法、查找表法、移位相加法、Booth法的原理和实现过程.以4×4和16×16数字乘法器的设计为例,通过在AlteraFPGA芯片上的仿真与综合,给出了这四种数字乘法器的运算速度和占用逻辑资源情况.结果表明随着位宽的变化,各方法的相对效果会有变化,对于具有较宽数据位的乘...     

An Efficient Scheduling Scheme for HSDPA System in Mixed Traffic Environments

In this letter, an efficient scheduling scheme is proposed to increase throughput of the mixed traffic over HSDPA system. The proposed scheme employs a channel-dependent adaptive delay barrier function to maximize throughput of besteffort services while satisfying the quality of VoIP services.     

Ultrafast Thermodynamic Control for Stable and Efficient Mixed Halide Perovskite Nanocrystals

Low photoluminescence quantum yield (PLQY) and spectra instability, the two most difficult challenges in blue‐emitting CsPbBr_xCl_3?x NCs, have not yet been solved. Quickly controlling the reaction thermodynamics is crucial to enhance crystallinity, thus PLQY and spectra stability, but it has been ignored until now. An ultrafast thermodynamic control (UTC) strategy is designed by utilizing liquid nitrogen to instantaneously freeze the superior crystal lattices of CsPbBr_xCl_3?x NCs formed at high temperature. The average cooling rate exhibits a 33‐fold increase compared to conventional ice‐water cooling (from 1.5 to 50 K s^?1). This UTC can make the reaction thermodynamic energy of the system lower than the threshold very quickly. Therefore, abrupt termination of further crystal growth can be achieved, which also avoids additional nucleation at low temperature. With the assist of defect passivation, the final blue‐emitting CsPbBr_xCl_3?x NCs exhibit an absolute PLQY of 98%, representing the highest value in Pb‐based blue perovskites to date. More importantly, they exhibit superior spectra instability. This UTC strategy not only represents a new avenue to synthesize perovskite NCs with excellent crystal quality and ultrahigh PLQY, but also provides a good reference to deal with the recognized bottleneck of spectra instability.     

An Efficient Critical Path Tracing Algorithm for Designing High Performance Vlsi Systems

Fast and correct timing verification is a critical issue in VLSIdesign. Several timing verification algorithms have been proposed in thelast few years. However, due to the huge computation time needed toeliminate false paths, existing algorithms have difficulty in performingtiming verification for large circuits. This paper presents efficientcritical path analysis algorithm based on test pattern generation with a newsensitization criterion. The algorithm does not require generation of a pathlist and elimination of false paths to find out the correct critical path ofthe circuit. The inputs which sensitize the critical path are determined aswell. The efficiency and speed of our algorithm are demonstrated using theISCAS benchmark circuits, and the critical paths are found in vastlyimproved times.     

一种片上系统(SOC)时钟同步设计方法

SoC设计很大程度上依赖于IP核的可重用性。由于各IP核中时钟延时的不同，要将IP核集成到一个同步SoC中时钟分布变得很难。本文介绍了一种SoC时钟同步设计方法，这种方法将可调节延时的时钟电路插入在时钟分布网络中．以取得时钟边沿的匹配和同步。使用可调节电路进行时序调整，减少了设计迭代时间，节约了设计成本。