简述极化SAR定标处理技术研究进展

极化定标是极化SAR数据用于图像解译和定量参数反演的关键步骤。综述了国内外极化SAR定标技术及应用研究的主要成果,着重介绍极化SAR定标技术发展以来取得的多种关键算法进展,系统梳理包括点目标定标算法、分布目标定标算法、法拉第旋转校正算法等技术原理介绍、参数定义估计及技术脉略发展分析,并讨论各技术方法在机载及星载SAR系统定标领域取得的应用发展现状,同时逐步分解该技术领域目前面临的技术难点及算法发展。最后探讨分析极化SAR定标技术发展中的未来需求难点和继续需要解决的问题,为研究人员进一步推动极化SAR定标技术发展提供参考。     

S-parameters-based high speed signal characterization of Al interconnect on low-k hydrogen silsesquioxane-Si substrate

The International Technology Roadmap for Semiconductors (ITRS) predicts that by 2010 over one billion transistors will be integrated into one chip [Semiconductor Industry Associations, International Technology Roadmap for Semiconductors, 2004. Available from: <http://public.itrs.net/Files/2004UpdateFinal/2004Update.htm>]. The interconnect system of this one billion transistor chip will provide the required high-speed signal and power to transmit each transistor on the chip. This system will deliver high frequency signals to various circuits, and the parasitic effects associated with interconnect will become evident and cannot be ignored. Small parasitic capacitance (C) between interconnect are required to reduce the crosstalk, power consumption, and RC delay associated with the metal interconnect system. Therefore, interconnect with low dielectric constant (k) materials is required.In this study, hydrogen silsesquioxane (HSQ) thin films prepared under various conditions are employed as the intermetal dielectric and the high frequency characteristics of Al-HSQ system are investigated and compared with those of Al-SiO₂ system. The S-parameters of the Al interconnect are measured for insertion loss and crosstalk noise. The interconnect transmission parameters are extracted from the S-parameters. A figure of merit (FOM) is employed to evaluate the characteristics of the Al-HSQ system at high frequencies (100 MHz-20 GHz). It is found that Al interconnect with HSQ films annealed at 400 °C has an insertion loss of 1.64 dB/mm, a coupling of −13.3 2 dB at 20 GHz, and a propagation delay of 0.121 ps/μm, while those of the PECVD SiO₂ films are 2.01 dB/mm (insertion loss), −13.40 dB (coupling), and 0.149 ps/μm (propagation delay). The Al-400 °C-annealed-HSQ system has better performance than the Al-SiO₂ system does from 100 MHz to 20 GHz. However, specimens with 350 °C-annealed HSQ films or plasma-treated HSQ films exhibit larger insertion losses and higher crosstalk noises than those with PECVD SiO₂ films do. Both annealing temperature and O₂ plasma treatment of the HSQ films affect the high frequency characteristics of the Al-HSQ system.     

一种基于统计特性估算串扰概率的方法

该文所提出的基于统计特性估算总线串扰概率的方法与以往基于数据流的方法相比，具有更短的运行时间，且精度相当，可以更有效地为综合工具采取相应避免措施提供参考依据。     

系统芯片IP核间互联总线串扰故障检测模型的BIST实现

文章针对系统芯片IP核间互联总线串扰故障的激励检测问题,在已经提出一种有效的串扰故障渐进式激励检测模型的基础上,给出了一种该渐进式模型的内建自测试(BIST)实现,对其中的测试矢量产生单元、测试响应分析单元以及测试控制单元进行了详细的分析。同时还给出了该BIST结构实现的参数化HDL描述,文章的最后给出了使用综合工具Synopsys对该BIST结构的综合结果。     

Crosstalk optimization for through-silicon vias by exploiting temporal signal misalignment

The vertical interconnects between the components of a 3D system-on-chip (SoC) are realized by through-silicon vias (TSVs). These large global vias are a frequent performance bottleneck due to their high capacitive crosstalk. In order to reduce it, this work analyses the effect of temporal misalignment between the transitions on the signal nets of an interconnect structure and presents a technique to exploit it. The approach, based on a crosstalk-aware net-to-TSV assignment and hardware-efficient low-power codes, enables a dramatic improvement in the 3D interconnect performance. Circuit simulations show that the proposed technique reduces the delay and the noise of modern TSV interconnects by about 35%–50%, without noticeable cost. In combination with the classical bus invert coding, an additional decrease in the energy consumption by about 17% is obtained.     

基于三值神经网络和混沌搜索的数字电路串扰时滞故障测试生成算法

提出了一种有效的串扰时滞故障测试生成算法,该算法使用了三值神经网络理论和混沌搜索方法。首先在电路的受害点处把电路分成两个部分,对第一部分,可以得到时滞时间表达式;对第二部分,使用混沌搜索和三值神经网络网络的方法把故障传播到输出端。最后,能够把故障传播到输出端且使时滞时间表达式取最大值的输入矢量就是串扰时滞故障的最优测试矢量。实验结果表明该算法能够容易地得到故障输入测试矢量,平均测试生成时间小于0. 25μs,故障覆盖率能够达到98. 2%。     

电路板上地保护走线的阻抗数学模型和串扰控制

文章提出了一种基于地保护走线的互连线的特性阻抗闭环计算公式,采用变分法结合横向传输线结构,分析地保护走线引起的两耦合信号线的耦合系数的变化。提出如何让地保护走线能很好的弥补串扰,还可以使传输线达到需求的稳定的特性阻抗。并且用高频三维电磁场仿真软件模拟仿真,并用矢量网络分析仪测量验证。     

17圆柱形混合棒塑料光纤耦合器中的串扰及其功率代价

研究17圆柱形混合棒塑料光纤耦合器(CMRC)中由于混合棒端面反射造成的结构性串扰,建立不同误码率条件下串扰与功率代价的关系。串扰与功率代价的关系表明,在误码率为10-9的条件下,17 CMRC的串扰小于-20dB时其功率代价接近于零。实验制作了17 CMRC,测得其端口间串扰为-23.5dB。为了进一步降低17 CMRC的串扰,试验了在混合棒的失配面上涂覆光吸收介质的方法。测量结果表明该方法可以使串扰降低5dB。     

WDM光网络中OADM的矩阵理论

该文用矢量和矩阵等数学工具对光网络中的OADM(Optical add-drop multiplexer)节点进行了全面的系统的理论分析,提出了一种新的OADM分析模型,并应用这种模型对光网络上传输的信号进行了详细的分析推导,得到了OADM环网中信号串扰的普适公式,为OADM及全光网的设计和分析提供了一种新的方法。     

一种基于邻域的小像元红外焦平面阵列串音测试方法

串音是评价红外焦平面阵列(InfraRed Focal Plane Array, IRFPA)性能的重要参数之一,随着IRFPA技术的发展,探测器单元尺寸逐渐减小,传统小光点测试方法的光斑尺寸已接近甚至大于探测器单元尺寸,需要采用新的测试理论和方法。论文分析了红外光斑照射到IRFPA上的典型分布情况,研究了小像元情况下探测器单元的信号电荷及其相互关系,建立了基于八邻域的小像元IRFPA串音测试的理论模型,并将四邻域串音模型和传统串音模型作为八邻域串音模型的特例,给出了相应的测试方法。数值模拟表明:在小像元情况下光斑尺寸对串音系数的测量具有明显的影响;采用基于邻域的小尺寸像元IRFPA串音测试方法,可在现有测试设备上通过测试软件的修改,实现小像元IRFPA串音的测试。