非均匀传输线间的串扰研究

应用时域有限差分法对非均匀传输线间的串扰耦合进行分析。基于细线散射的时域有限差分法分析非均匀结构时,采用阶梯式均匀传输线模型,对非均匀传输线进行分段逼近。针对不等长、线径变化、非平行线和交叉线4种情况分析其参数变化对串扰的影响。研究表明：不等长电缆超出部分长度对串扰耦合幅度影响较小,对谐振频率影响较大;电缆线径的变化对其串扰耦合影响较小;非平行线和交叉线的角度对电缆间串扰的影响较大。     

The experimental evaluation of flat periodic transmission lines for use as an information source in automated transportation systems

A brief summary of some past studies of the use of transmission lines as an information source for automated ground transportation systems is presented. One method, which involves the use of helically wound transmission lines, was found to be promising [6] but such lines are difficult to implement. Here the geometry-dependent properties of the magnetic-field distribution of flat periodic transmission lines is developed. It is found that such lines should be usable as a replacement for helically wound lines. The results of an experimental evaluation of several flat lines are presented with emphasis on triangular-shaped lines. It is found that the performance characteristics are even better than those of the helically wound line.     

非平行微带线间的串扰抵消研究

非平行微带线是印刷电路板(PCB)上不可避免的互连结构。针对PCB 上非平行微带线间的串扰问题,用平行微带线近似非平行微带线,把平行耦合微带线间的串扰抵消方法应用到非平行耦合微带线中,提出了利用耦合传输线信道传输矩阵方法来进行远端串扰抵消,在对非平行耦合传输线信道传输矩阵进行特征值分解的基础上构建串扰抵消电路。仿真了非平行微带线间夹角分别为q=3°、5°、10°时的串扰,结果表明,该方法可以有效改善非平行微带线上信号眼图的质量,串扰抵消效果良好。     

Condition of modal analysis in time domain of lossy coupled lines

Modal decomposition in the time domain is shown to be applicable to lossy coupled transmission lines of equal width. It is rigorous for two lines and is a good approximation for more than two lines. This allows a direct time-domain simulation of buses made of microstrip lossy lines on chip or on board in digital circuits     

直升机防撞系统的电力线检测方法

使用防撞系统探测电力线,对低能见度条件下直升机的低空飞行安全至关重要。通过理论分析,介绍了电力线的布拉格散射特征。在静态条件下,利用毫米波收发系统对电力线的散射特性进行了试验验证。在运动条件下进行运动补偿,将电力线的布拉格散射回波和输电铁塔的强回波峰进行图像累积,并利用霍夫变换进行电力线提取。试验结果可清晰地检测到电力线,证明了处理模型和方法的正确性。     

Class of nonuniform multilayer RC distributed networks

A simple alternative solution is given to the problem of obtaining the network parameters of a class of multilayer RC lines considered recently by Singhal and Wing. It is further shown that, as in the single-layer lines, the transmission parameters are interrelated, and the transposes of these parameters satisfy either the current or the voltage differential equation of the multilayer lines. An exact equivalent circuit, using ideal transformers, is given for this class of multilayer lines in terms of single-layer lines.     

Void formation mechanism in VLSI aluminum metallization

Void formation is aluminum lines caused by high-temperature heat treatment has been investigated, particularly from the aspect of mechanical interaction between the passivation layer and aluminum lines. It is found that there are two effects causing voids in aluminum lines: the deformation of the passivation layer and the so-called thermal expansion mismatch between aluminum lines and their surrounding layers. While the thermal expansion effect is independent of aluminum line dimensions, the passivation deformation effect dominates preferentially in wide aluminum lines. Bulge deformation of the passivation layer is caused by its own compressive stress, forcing the encapsulated aluminum to expand. In fine lines, void formation is controlled by the volume difference caused by the thermal expansion mismatch and aluminum diffusion     

外场作用双导线的电磁耦合时域分析方法

基于时域有限差分（finite-difference time-domain，FDTD）法和传输线方程，并结合插值技术，研究了一种高效的时域混合算法，能够快速模拟电磁波照射自由空间和屏蔽腔内双导体传输线的电磁耦合，并实现空间电磁场与双导线瞬态响应的同步计算.该算法先采用FDTD方法模拟双导线周围空间的电磁场分布，结合插值技术构建适用于双导线电磁耦合的传输线方程，再采用FDTD的中心差分格式进行离散，从而求解得到传输线和端接负载上的瞬态响应.同时，分析双导线间距对其电磁耦合的影响，掌握其耦合规律.通过相应数值算例的模拟，并与FDTD方法进行对比，验证了该时域混合算法的正确性和高效性.     

端接非线性负载的非均匀传输线瞬态分析

在均匀多导体传输线的时域有限差分法(FDTD)基础上，对非均匀多导体传输线及端接非线性负载的情况进行了分析。结果表明：对于非均匀多导体传输线，采用FDTD法进行瞬态分析极为方便，并且可以处理端接非线性负载的情况；同时，还可获得线上各点的电压、电流波过程。通过实例验证了所提出的FDTD算法的有效性，可用于传输线波过程的研究。     

Crosstalk between microstrip transmission lines

Methods for prediction of crosstalk between microstrip transmission lines are reviewed and simplified for the weak-coupling case. Classical coupled transmission line theory is used for uniform lines, and potential and induced EMF methods are used for crosstalk between nonuniform lines. It is shown that the potential method is equivalent to classical coupled transmission line theory for the case of uniform lines. An experiment was performed for uniform coupled microstrip lines for frequencies from 50 MHz to 5 GHz, and good agreement between theory and measurement was obtained for both near- and far-end crosstalk     

一种快速稳定的倾斜文档校正方法

在文档扫描数字化过程中会出现倾斜,依据文档图像自身的线条和文字行特征,提出了一种快速而稳健的文档校正算法.该算法首先对文本进行数学形态学处理、边缘检测,然后利用直线拟合技术得到直线,从中筛选出有代表性的直线,通过直线与主轴方向的夹角检测出角度,最后对图像进行旋转校正.通过实验验证以及与目前具有相关代表性的方法对比,论证...     

利用增强等离子体谱线反演高精度电子密度

提出了一种基于非相干散射雷达(incoherent scatter radar,ISR)等离子体谱线提取高精度电子密度的方法.以欧洲非相干散射雷达科学联合会(European Incoherent Scatter Scientific Association,EISCAT)在2015年10月31日14:00—14:09...     

Open Wire Lines

The properties of two-wire lines and single wire lines (surface wave transmission lines) are discussed on a comparative basis. The two-wire line is actually a system of two coupled single wire lines and thus requires a high degree of symmetry to maintain the desired wave mode. While the single wire line is more affected by bends it has the advantages that it is simpler in construction and is less susceptible to weather conditions. The main domain of the two-wire lines lies in the frequency range below 100 mc and that of the single wire line in the range above 100 mc.     

Characterization of Co-Planar Silicon Transmission Lines With and Without Slow-Wave Effect

Co-planar lines on silicon substrates with and without slow-wave effect are characterized using time-domain reflectometry (TDR) and vector network analyzer (VNA) measurements, and simulated using a proposed nonphysical resistance-inductance-conductance-capacitance (RLGC) model. The silicon co-planar lines are characterized based on comparison to package transmission lines. Co-planar silicon lines without slow-wave mode are modeled in the same way as package transmission lines, but co-planar lines with slow-wave mode are modeled in a different way from package transmission lines. Hence, a nonphysical RLGC model including slow-wave mode is proposed along with the extraction method from VNA measurements. Simulation results correlate well with time- and frequency-domain measurements for the co-planar silicon lines.     

有机聚合物光波导延迟线研制的新进展

由于孔径效应和孔径渡越时间的限制,传统的相控阵雷达难以在大扫描角下实现大瞬时带宽,有机聚合物光波导延迟线可解决这一问题。先介绍了有机聚合物光波导延迟线的原理和优点,接着综述了三种延迟线：利用聚酰亚胺制成的4位有机聚合物光波导延迟线,多层结构的有机聚合物光波导延迟线,开关选择的超长有机聚合物光波导延迟线。     

Perturbations impulsionnelles créées par un champ électromagnétique non uniforme sur des câbles multiconducteurs

The purpose of this paper is to show the effects of electromagnetic pulses (emp) on multiconductor transmission lines. The response of multiconductor transmission lines excited by an electromagnetic field, suspended over a reference conductor, in homogeneous and/or in-homogeneous medium is obtained. In quasi-tem assumption, we derive matrix expressions of the terminated voltages and currents. Experimental and numerical results, related to short lines, power lines, microstrip lines, shielded isdn bus illuminated by an electromagnetic field show how the perturbations can be reduced.     

耦合微带线的散射参数特性分析

针对耦合微带线的散射参数在一些频率点处呈现出波峰、波谷现象,该文根据微波网络理论,从两根平行微带线的奇模和偶模的散射参数出发,推导出四端口网络散射参数的波峰、波谷处频率与并行长度和线间距的关系。同时分别在频域和时域研究了两根平行微带结构的插入损耗对信号传输的影响。经分析发现,由于微带线间的耦合,波峰、波谷处的频率随线间距增大而提高,随长度增大而降低;而且在串扰产生的同时,所传输的信号也有一定程度的衰减。     

A low-power charge-recycling ROM architecture

This paper describes a newly proposed low-power charge-recycling read-only memory (CR-ROM) architecture. The CR-ROM reduces the power consumption in bit lines, word lines, and precharge lines by recycling the previously used charge. In the proposed CR-ROM, bit-line swing voltage is lowered by the charge recycling between bit lines. When N bit lines recycle their charges, the swing voltage and the power of the bit lines become 1/N and 1/N/sup 2/ compared to the conventional ROMs, respectively. As the number of N increases, the power saving in bit lines becomes salient. Also, power consumption in word lines and precharge lines can be reduced theoretically to half by the proposed charge-recycling techniques. The simulation results show that the CR-ROM consumes 60%/spl sim/85% of the conventional low-power ROMs with 1 K /spl times/ 32 b. A CR-ROM with 32 Kb was implemented in a 0.35-/spl mu/m CMOS process. The power dissipation is 6.60 mW at 100 MHz with 3.3 V and the maximum operating clock frequency is 150 MHz.     

激光雷达在电力巡线应用中的计算方法

针对激光雷达在电力巡线中的深度应用,通过数学建模,对基于三维激光点云的输电杆塔倾斜、电力线弧垂、多电力线交叉跨越、电力线周围净空排查等巡线作业重点关注的参数建立计算方法,克服了激光雷达常规内业数据处理中过份依赖专用商业软件的问题。用实际激光点云数据进测试,效果良好,进一步提升了激光雷达在电力巡线中的优势和效能。     

The effect of straight- and U-shaped lines on quality

Straight lines and U-lines are two commonly used layouts for production lines. To date, no research has studied the effect of these layouts on the quality of the products produced by the line. This paper examines U-shaped lines and straight lines from the viewpoint of their effect on quality, which is organized into Juran's quality planning, quality control, and quality improvement categories. Two or more quantitative measures are developed for each quality category, the effect of the shape of the line on the values of these measures is carefully analyzed, and the implications for problems of realistic size are discussed. The authors find that U-shaped lines outperform straight lines in all of the aspects of quality they examined