抗SPA攻击的Twisted Edwards曲线标量乘法实现

椭圆曲线密码（Elliptic Curve Cryptography,ECC）是一种非对称密码，在信息安全领域中扮演着越来越重要的角色。目前对椭圆曲线密码的研究大多针对Weierstrass曲线，对于Twisted Edwards曲线的研究较少。针对Twisted Edwards曲线上标量乘法的效率及安全性，将Twisted Edwards曲线转换为Montgomery曲线，并采用Montgomery标量乘法在每次循环中都固定进行点加和倍点计算，从而能够抵抗简单能量攻击（Simple Power Analysis,SPA）。最后在复旦微电子公司型号为JFM7K325T的现场可编程门阵列（Field Programmable Gate Array,FPGA）中进行了实现和测试。结果表明，该方法能达到较理想的效果。     

通用工艺与设备

Y2002-63234-325 0302841低 K 电介质的电子束处理及设备=Advanced EB-cureprocess and equipment for low-K dielectric[会,英]/On-ishi,T.& Nagaseki,K.//2001 IEEE InternationalSymposium on Semiconductor Manufacturing.—325～328(E)Y2002-63239-163 0302842多晶硅表面微加工 MEMS 结构制备=Fabrication ofpolysilicon surface micromachined MEMS structures[会,英]/Munger,K.& Fuller,L.F.//2001 IEEE Uni-versity/Government/Industry Microelectronics Sympo-sium.—163～166(E)     

基于MultiBoot的超声设备FPGA更新保护设计

超声台车系统由于体积大,机械外壳不建议频繁拆卸,因此必须考虑FPGA烧录的问题。传统FPGA升级方式往往需要通过JTAG升级,而这种方式必须拆卸外壳。文章基于Xilinx公司的XC7K325T芯片,采用MultiBoot原理研究了一款超声设备FPGA固件升级的更新保护设计。经理论和实际验证,该设计符合预期效果,能成功应用到超声台车系统中。     

AD9548：可利用GPS信号进行同步的时钟IC

ADI推出一款时钟IC，使系统设计人员能使用标准的、无处不在的免费1pps GPS（全球定位系统）卫星发射机的信号，为通信基础设施设备产生同步时钟信号。AD9548时钟发生器，同步器设计用于远程光网络和无线网络节点、有线基础设施和数据通信设备，     

同步时钟设备测试能一种方法及性能分析

可靠的通信依赖于网中数据信号良好的同步，在通信网中，由于种种原因，比如漂移损伤、抖动损伤、节点时钟振荡器的老化和环境温度的变化等等，都会对通信质量产生很大的影响，严重时将会给运营商带来很大的损失，所以当有设备新接人时和出现故障时，对同步时钟设备精准地测试和性能指标的分析变得非常必要。下面以青浦城厢局的中兴小灵通ICSC设备站时钟测试为案例来分析如何对同步时钟设备进行测试和指标分析。     

中央广播电视总台4K超高清播出系统时钟监测方案浅析

中央广播电视总台4K超高清播出系统的时钟系统主要是以NTP网络时间协议来进行授时。为了保障系统中时钟的准确性,监控系统对各级设备都进行了时间监测。本文介绍了该套系统中时钟系统的基本架构,各级设备的时钟报警情况以及监控系统利用NTP协议来监测时钟源时间的比对算法。     

卓联半导体数字时钟芯片

卓联半导体公司(Zarlink Semiconductor)推出一款新DPLL芯片ZL30109，该芯片可为宽带设备提供更高的灵活性和电信级性能。卓联为全球网络应用提供齐全PDH时钟芯片，涵盖了线路卡时钟产生、多种输出、再到位于中心局设备中的时钟控制等应用领域。ZL30109芯片是一款单片硅器件，非常适合应用于高速终端产品和接人网络设备，     

应用矢量信号发生器产生MLS信号

本文简单介绍了微波着陆系统的原理，重点阐述了应用矢量信号发生器产生MLS信号的过程及实现方法，并对此信号进行了详细测试，这种方法与传统的MLS产生方法相比有许多明显的优势，不但可以简化MLS接收设备的调试，还可以进一步提高微波着陆系统的测试精度。     

SDH网络的指针调整机制及故障分析（上）

在SDH传输网络中，要求各个节点设备保持时钟同步，以保证业务的传输质量。但是由于种种原因，网络中各节点SDH设备的时钟不可能绝对地同步，总存在着或多或少的差异，例如：时钟频率差异和时钟相位差，这就对业务的传输质量带来一定的影响。表现在业务信号流经过的SDH设备上出现指针调整，业务流的输出抖动和漂移增加，严重时将使业务信号流产生滑动误码现象。     

雷电在电信和信令网中引起的预期浪涌（K．67）（二）

7．4邻近电信线路的雷闪 7．4．1概述 一些国家研究了电信网络某些转变点的预期雷电浪涌电压和电流的峰值，并在《雷电手册》第10章中报告了这些调查结果。ITU—T K．20、K．21和K．45建议书为电信设备确定的同有抗力要求，它们是以《雷电手册》第十章的调查结果为依据的。     

ILS与VOR分析仪数字中频处理技术研究与实现

本文对仪表着陆与全向信标分析仪中航向信标信号基于FPGA的数字中频处理技术进行了研究,提出了一种基于数据分离滤波的数字中频处理方案。与传统的数字中频处理方案相比,对LOC多频调制信号进行了分离测量,提高了测试的精度,对仪表着陆与全向信标分析仪广泛应用于机场校飞、日常监测和设备维护有着重要的意义。     

New data regeneration scheme for multi-Gbit/s fibre-optic links

A novel optical regeneration scheme without using nonlinear clock recovery elements has been demonstrated in a transmission experiment at 2.4 Gbit/s over 35 km of fibre. In this scheme, the clock is superimposed on the data signal at the transmitter end, and is separated from the composite signal by passive filters at the receiver end for data regeneration     

恶化非归零码信号的全光时钟恢复

全光时钟提取结构应对输入信号的恶化程度有一定的容忍度.在一种半导体光放大器(SOA) 啁啾光纤布拉格光栅(CFBG) 受激布里渊散射(SBS)的方式实现非归零(NRZ)码信号的全光时钟提取结构中,半导体光放大器和啁啾光纤布拉格光栅共同作用实现了非归零码信号的时钟分量增强,基于受激布里渊散射的全光时钟提取结构提取出非归零码的光时钟信号.实验通过对不同恶化程度的非归零码信号的时钟提取比较发现,恶化信号的信噪比是影响光时钟提取的关键.输入非归零码信号的信噪比越差,光时钟信号光谱的噪声水平越高,提取出的光时钟信号的幅度越低.当时钟增强非归零码信号的时钟数据抑制比低于-10 dB时,无法实现非归零码信号的时钟提取.     

Optical Clock Recovery Using a Polarization-Modulator-Based Frequency-Doubling Optoelectronic Oscillator

We propose and demonstrate a flexible optical clock recovery scheme using a polarization-modulator-based frequency-doubling optoelectronic oscillator (OEO). The proposed system can extract both prescaled clock and line-rate clock from a degraded high-speed digital signal using only low-frequency devices. A simple theory is developed to study the physical basis of the optical clock recovery. The OEO operation from a free-running mode to an injection-locking mode is investigated. The locking range is quantitatively predicted. An experiment is then implemented to verify the proposed scheme. A prescaled clock at 10 GHz and a line-rate clock at 20 GHz are successfully extracted from a degraded 20 Gb/s optical time-division-multiplexed (OTDM) signal. The locking range and the phase noise performance are also experimentally investigated. Clock recovery from data signals that have no explicit subharmonic tone is also achieved. The proposed system can be modified to extract prescaled clock and line-rate clock from 160 Gb/s data signal using all 40-GHz devices.      

基于FPGA的光纤通信系统中帧同步头检测设计

为实现设备中存在的低速数据光纤通信的同步复接／分接,提出一种基于FPGA的帧同步头信号提取检测方案,其中帧头由7位巴克码1110010组成,在数据的接收端首先从复接数据中提取时钟信号,进而检测帧同步信号,为数字分接提供起始信号,以实现数据的同步分接。买验表明,此方案成功地在光纤通信系统的接收端检测到帧同步信号,从而实现了数据的正确分接。     

Clock synchronization for packet networks using a weighted least‐squares error filtering technique and enabling circuit emulation service

Circuit emulation service (CES) allows time‐division multiplexing (TDM) services (T1/E1 and T3/E3 circuits) to be transparently extended across a packet network. With circuit emulation over IP, for instance, TDM data received from an external device at the edge of an IP network is converted to IP packets, sent through the IP network, passed out of the IP network to its destination, and reassembled into TDM bit stream. Clock synchronization is very important for CES. This paper presents a clock synchronization scheme based on a double exponential filtering technique and a linear process model. The linear process model is used to describe the behaviour of clock synchronization errors between a transmitter and a receiver. In the clock synchronization scheme, the transmitter periodically sends explicit time indications or timestamps to a receiver to enable the receiver to synchronize its local clock to the transmitter's clock. A phase‐locked loop (PLL) at the receiver processes the transmitted timestamps to generate timing signal for the receiver. The PLL has a simple implementation and provides both fast responsiveness (i.e. fast acquisition of transmitter frequency at a receiver) and significant jitter reduction in the locked state. Copyright © 2006 John Wiley & Sons, Ltd.     

Burst-Mode Clock Recovery Utilizing Relaxation Oscillation in Directly Modulated Lasers

A novel clock recovery scheme utilizing the relaxation oscillation in a directly modulated laser (DML) for burst-mode transmission is proposed for the first time. In this scheme, the DML generates the clock tone along with the transmitted non-return-to-zero data in the optical signal. An injection-locked oscillator (ILO) is employed in the receiver to extract the clock tone and restore the clock. The proposed scheme is investigated systematically and verified by simulations with different laser modulation currents as well as some nonideal characteristics of the system. The simulation results show that the low cost clock recovery method using an ILO in an optical link using a regular DML is highly efficient for burst-mode transmission at 10 Gbps.     

用于高Gb／s光通信系统的新型时钟提取电路

新型时钟提取电路省去传统提取电路中的非线性处理电路，从而简化了接收设备。在利用这种电路的光通信系统中，在发送端，时钟脉冲叠加在数字信号上；在接收端，主放电路以后分成两个通路，一通路接有一个Ｎｙｑｕｉｓｔ滤波器，只允许信号脉冲通过，另一路则接有一窄带滤波器，实现时钟信号的提取。为了验证此方案的可实现性，研制出一套１．２４４Ｇｂ／ｓ光通信系统。本文从理论上分析这种光通信接收机的灵敏度与时钟脉冲调制度及时移的关系，并与实验结果相对比。另一方面，还建立了一个简单的公式计算所提取的时钟信号抖动值。     

仪表着陆系统飞行校验周期延长研究

仪表着陆系统是飞机进近着陆的关键设备，其信号质量直接影响民航安全运行水平， 为确保其持续正常，按照民航规章，每 6 个月要对其进行一次定期飞行校验，随着设备数量的持续增加，给校验运力和航班支持率带来了极大困难。另一方面，设备运行单位外场信号测试手段不断丰富，有效地补充了对仪表着陆系统空间导航信号的日常监测。因此中国民航可进行试点尝试，根据设备运行状况合理设置校验周期，成熟后开始推广应用。     

Bit rate and wavelength transparent all-optical clock recovery scheme for NRZ-coded PRBS signals

All-optical clock recovery from 40-Gb/s nonreturn-to-zero (NRZ) pseudorandom binary sequence data streams based on self-pulsating lasers is presented. A compact preprocessing circuit is utilized to convert an NRZ signal to a pseudoreturn-to-zero sequence before injecting into the optical clock. It comprises a semiconductor optical amplifier followed by a periodical wavelength-division-multiplexing demultiplexer filter. A stable sinusoidal clock signal with a root-mean-square jitter below 700 fs is detected at the output of the self-pulsating laser within data dynamic range of more than 8 dB. The performance of the all-optical clock recovery scheme is investigated by varying the bit rates between 39.81 and 43.02 Gb/s as well as for various wavelengths in the C-band.