Fast,compact and symmetric modular exponentiation architecture by common-multiplicand Montgomery modular multiplications

In this paper, the primitive common-multiplicand Montgomery modular multiplication is developed for modular exponentiation. Together with Montgomery powering ladder, a fast, compact and symmetric modular exponentiation architecture is proposed for hardware implementation. The architecture consists of one group of processing elements along the central line and two symmetric groups of accumulation units on two sides. The central elements perform modular reductions, while the symmetric units on both sides accumulate the modular multiplication results. A feedforwarding architecture is employed to decrease the latency between processing elements, in parallel with the word-based accumulation units, which are also pipelined. Meanwhile, due to the symmetric architecture and Montgomery powering ladder, the modular exponentiation is immune from fault and simple power attacks. Implemented in FPGA platform, the performance of our proposed design outperforms most results so far in the literature.     

Fast calculation of impulse responses without multiplications

The impulse response of a linear system may be calculated from the response to a pseudorandom sequence. If the calculation is based on the fast Hadamard transform, only additions and subtractions are required.     

High-speed complex-number multiplications based on redundant binary representation of partial products

The complex-number multiplier is one of the key arithmetic components for the baseband signal processing of modern digital communication systems such as channel equalization, timing recovery, modulation and demodulation. This paper presents two algorithms suitable for a high-speed complex-number multiplier, which are based on redundant binary (RB) representation of partial products. The basic idea behind our approach is to convert a pair of binary partial products into a RB form so that the post-addition/subtraction which is inevitable in the conventional methods based on binary multiplication, is eliminated. With the proposed algorithms, the complex-number multiplication is reduced to two RB multiplications, one for the real part and the other for the imaginary part. The RB multiplication is defined by an addition of RB partial products, and is performed in parallel without carry propagation from the least-significant digit to the most-significant digit. This work results not only in simplified arithmetic operations, but also in highly parallel and simple architecture when compared with conventional methods using binary multiplications. To demonstrate the algorithms, two test chips have been implemented using a 0.8µm CMOS technology.     

Wireless sensor networks based on modular arithmetic

The authors propose the method for data coding in wireless sensor networks (WSN) based on the transformation of the residue number system and multipath routing. It enables to utilize efficiently the bandwidth of communication channels as well as reduce message delivery time. It is explored the ant algorithm to search an optimal route of data transmission in the wireless sensor network. There is introduced a limitation for the communication radius of the wireless unit that shorts a number of the search decision modes and improves the accuracy of the wireless network simulation. The correspondent software is designed, it allowes exploring the dynamics of finding the optimal transmission path in WSN in case of different algorithm settings, and exploring the impact of the elite ants on the accuracy of the found path.     

一种基于分块个体子空间的人脸识别方法

针对传统PCA算法的局限性,本文提出了一种基于个体子空间和分块特征提取的人脸识别方法。该方法不同于传统的PCA算法,它为每一个体人脸对象建立一个该个体对象所独有的人脸子空间,并且运用分块特征提取,加强了对样本局部特征信息的提取。在识别过程中,将待测人脸图像对不同个体人脸子空间进行投影后,再运用最近距离分类原则进行分类识别。该方法相对于传统的PCA算法能够更好地描述不同个体人脸之间的差异性,克服各类噪声。本文的实验结果表明,该方法的识别率相对于传统PCA特征脸算法具有一定的提高,能够较好地克服光照、表情和姿态变化的影响。     

基于STM32的模块化平衡车设计

介绍了一种基于模块化设计的两轮自平衡小车,分析了系统软硬件模块和调试过程.为了增强系统灵活性,设计了上位机和手机应用,对小车姿态数据进行实时显示、对系统参数进行实时调节.实践表明,模块化设计的自平衡小车控制稳定,调试方便,扩展灵活.     

基于模运算的客运站车辆调度算法的设计

为了满足经济欠发达中小城市的中小客运站计算机联网售票的需求,设计了一个基于模运算的车辆调度算法。本算法已经应用到一套基于J2EE的售票管理软件中,该售票系统运行在B/S模式下,具有很好的跨平台性和兼容性,能实现跨区域、跨系统、跨平台的联网售票。该售票系统自交付使用至今已使用了近4年,期间经过多次修改,目前系统运行已经较为稳定,具有很好的应用推广价值。     

基于MSFM的快速图像修补算法

近年来,基于非线性高阶偏微分方程的高质量图像修补算法已经得到了发展,但这些方法需要大量的迭代,时间开销大,复杂度高.Telea提出的基于FMM的修补算法可以快速完成修补,但存在行进方向和边缘信息保持的问题.对此进行了改进,采用MFM方法,并引入扩散张量.实验结果表明提出的方法可以达到较高的质量,而且速度快.     

Fast GF(p) modular inversion algorithm suitable for VLSIimplementation

A new, efficient algorithm for modular inversion in Galois field GF(p) is presented. Very large scale integration (VLSI) implementation of the algorithm is described and the high performance and low silicon penalty is demonstrated     

基于Montgomery模乘的RSA算法VLSI实现

介绍了一种基于可伸展的Montgomery模乘结构的1024位RSA加解密芯片实现。设计采用的新型心动阵列结构，可以有在有效控制芯片面积的前提下，极大地提高运算频率，从而提高运算速度。经过ModelSim仿真和Design Compiler综合，与当前已发表的RSA芯片设计相比，该设计在面积和速度上均有优势。     

一种基于CSA加法器的Montgomery模幂乘硬件实现算法

提出了一种改进的Montgomery模乘和模幂算法,该算法采用5-to-2 CSA加法器来实现Montgomery模乘算法中的超长大数加法。目前使用CSA加法器的其他模乘算法在模乘结果输出时均需要用CPA加法器来处理CSA加法器的输出结果,而本文提出的算法使得模乘运算的输入输出操作数均可采用保留进位形式,避免了进行超长操作数的CPA加法这一耗时的操作,因此显著减少了模乘运算所需时钟周期,提高了数据处理的时间效率,并加快了RSA模幂运算的速度。     

基于DSP模型的快速代码的生成

TMS320F2812DSP是控制系统开发中很好的硬件设计平台,但传统的TI DSP代码开发方法周期较长,效率不高。为了在实际控制系统开发中缩短控制算法的设计周期,提高控制器的可靠性,并简化在调试过程中对控制算法的修改,设计与开发了基于DSP的快速原型控制系统。该系统包括基于TI F2812DSP的硬件控制器和基于Matlab/Simulink的软件开发环境。用户可以在Simulink环境中利用RTW功能直接从Simulink模型自动生成可执行代码并下载到目标板,直接运行程序,从而简化DSP系统开发过程,提高开发效率。通过闪烁灯实验实时控制实验,验证了系统的有效性。     

基于熵特征的快速格网逼近

不规则三角格网表示以其优越的性能在地形高度场数据的简化中得到了广州应用。在不规则三角格网生成的过程中,插入点的选取是关系到最终简化后的地形逼近质量好坏的关键。由于通常将在每一个点上计算得到的重要性测度作为插入点选取的依据,因此重要性测度准则的选取成为研究的重点。文中在对传统重要性测度计算方法的性能比较和分析基础上,提出了一种基于局部熵的重要性测度计算准则。实验结果表明,基于局部熵准则的插入点选取方法在各项性能上均优于传统的方法,并且有效地克服了以往方法中的“短视性”问题。     

基才时间信息的快速检索方法探究

本文研究了利用时间信息实现快速检索视频文件的方法,视频文件的压缩编码标准采用的是H．264,该方法主要包括视频分析和视频检索两个部分的研究。在视频分析部分,对码流中的IDR帧（关键帧）进行抓取和获得其时间、位置、大小等信息。并将得到的时间等信息存入至数据库。该部分的重点是时间信息的获取,由于负责传输码流的RTP数据分组的时间戳记录了码流的时间信息,所以着重描述了获取并且记录RTP时间戳的过程。视频检索部分,利用时间等查询条件从数据库中进行视频检索。对所述方法进行研究。结果表明使用该方法能够快速查看某时刻视频内容．避免了检索视频时的重复处理。     

基于DSP的快速以太网通信技术研究

为了适应大量的嵌入式产品的网络接入需求,目前市场上的主流嵌入式操作系统都包含了TCP/IP网络协议栈.这些商品化的TCP/IP协议栈运行可靠、性能也非常好,但是价格较高,降低了市场竞争力.     

Bit-level systolic arrays for finite-field multiplications

Galois-field multiplication algorithms and their systolic realizations are proposed. Parallel and serial architectures as well as their VLSI implementations are presented. They are based on the standard-basis representation of the Galois-field elements. Our algorithms allow the two operands to enter the systolic arrays in the same order. Only one control signal for the serial systolic array is required as compared to two in the previous design. Our multipliers are more regular and modular, requiring simple control signal, and compact in terms of silicon area; they are well suited to VLSI implementation. Expansion to higher order Galois fields are easier to realize than other multipliers. High throughput rates are achieved due to their systolic array architectures. This work was supported in part by the National Science Council, R.O.C., under Contracts NSC80-0404-E007-02 and NSC80-0404-E007-33.     

Fast on-line OSNR measurements based on polarisation-nulling method with downhill simplex algorithm

A fast on-line OSNR measurement technique which uses the downhill simplex algorithm as a minimum finder is proposed and tested in CW signals for different OSNR levels with excellent agreement. The method is shown to be stable after 8 h of uninterrupted operation and is not affected by environmental temperature change during the test.     

一种基于三模冗余的智能复合传感器设计

提出了一种基于三模冗余的智能复合传感器的设计方法,能对环境温度、相对湿度与绝对压力进行测量。为了提高测量的精度,延长产品的寿命,传感器采集的环境参量均从3个敏感元件获得,并通过智能处理器对其进行智能判读,剔除误差较大或错误的数据,实现三模冗余,使得即使有一个敏感元件失效,所设计的传感器依然能正常工作并且能上报故障状态,极大地提高了传感器的可靠性与使用寿命。经过试验,设计的传感器在-40⁸5℃的环境中,温度采集精度优于0.5℃,相对湿度采集精度优于3%,绝对压力采集精度优于0.1 kPa。该型复合传感器现已完成样机试制,具有重要工程应用价值。     

基于模运算标签分类的RFID标签防碰撞识别方法

为了解决射频识别(RFID)系统中的多标签防碰撞问题,在分析帧时隙ALOHA算法的基础上,提出一种基于模运算标签分类的RFID标签防碰撞识别方法。引入一种检测信息碰撞的时隙选择信息,对标签所选取时隙的碰撞情况进行分析并估计标签数量;然后对标签EPC编码进行逐级的取模运算,将同余的标签归为一组。各个标签经过K次取模运算后,分为2k组,每组只有发生少量碰撞位的标签。再将标签按照分组对应的时隙发送,碰撞标签采用二叉树后退式算法处理。本方法极大的提高了标签的识别效率,适用于射频识别系统中阅读器对于大量电子标签的快速识别。     

基于快速曲波变换的图像水印算法

提出了一种新的基于曲波变换的数字图像水印算法。首先,利用快速曲波变换对原始载体图像进行多分辨率分解,并对待嵌入的水印图像进行Arnold置乱;然后,根据人类视觉特征和曲波系数分布特点,将水印信息嵌入到原始图像的中高频系数中。实验结果表明,该算法具有好的不可见性和安全性,对噪声、裁剪、滤波、JPEG压缩等攻击有好的鲁棒性。