乘法器在信号处理中的应用

介绍了乘法器的使用原理,详细介绍了利用乘法器进行信号处理,调整乘法器的输入进行差模测试的设计过程。     

模拟数字混合乘法器矢量测量的原理及应用

首先介绍了一种矢量测量的新原理，并对该测量原理的幅度误差和相位误差进行了理论分析。然后，仿真分析了谐波分析的矢量误差，并给出了相应的实验测试结果。结果表明，相位测量的理论误差为零，幅度测量的理论误差可用修正系数消除，且使用较低位数的D／A转换器，可得到高准确度的结果。最后，给出此种矢量测量原理应用的几种方案。     

低成本实用模拟乘法器设计

本文介绍了利用通常器件构成的一种低成本模拟乘法器。分析了其工作原理和应用条件．最后给出了具体的实现电路。     

被动免疫算法在模拟电路故障诊断中的应用研究

基于生物免疫系统的信息处理机理,介绍了被动免疫算法的实现过程,并将其应用到某装备电路板的故障诊断之中。该算法具有边检测边学习的动态调整功能,仿真和实验实例表明,该算法适合于电路板的故障诊断,有较高的故障诊断率。     

PSPICE结合MATLAR在模拟电路故障诊断中的应用研究

本文将MATLAB与PSPICE有效的结合在一起,着重通过一个模拟电路实例说明了PSPICE和MATLAB的数据通信在模拟电路故障诊断中的应用方法。实验结果表明,将PSPICE仿真所得的数据输入给MATLAB进行分析处理,能够进一步对仿真结果提取更有效的故障特征。     

基于AD9923A的ICX274模拟前端电路设计

ICX274是SONY公司生产的每秒15帧200万像素高速CCD,针对ICX274的模拟前端电路(Analog front end,AFE),本文给出了基于Analog Devices公司芯片AD9923的硬件电路和寄存器设置方法.AD9923芯片内部功能电路模块通过SPI接口控制相关寄存器实现,通过分析AD9923内部主要电路模块的工作原理,介绍了与之相关电路的寄存器控制方法.对比SONY方案可以看出,该设计硬件结构简单、成本低、可靠性高.测试表明,驱动时序控制满足ICX274时序要求,可以驱动ICX274输出模拟视频信号,能正确控制相关双采样电路的采样时刻,完成模拟数字转换得到CCD的数字视频信号.     

电路模拟方法在数学建模中的应用

本文采用电路模拟的方法来预测2008年北京奥运会体育场馆周围商区的消费需求情况.首先根据道路拓扑结构提取出相应电路结构,在每条导线(代表道路)上设置一个较大的控制电阻,根据电阻的阻值控制人流的流动规律,使电流和人流一样按一定比例选择可行的道路;同时在每条导线上串联一个较小的采样电阻,根据该电阻上的电压可求得该商区的人流量或消费需求.     

电路模拟方法在数学建模中的应用

本文采用电路模拟的方法来预测2008年北京奥运会体育场馆周围商区的消费需求情况。首先根据道路拓扑结构提取出相应电路结构,在每条导线(代表道路)上设置一个较大的控制电阻,根据电阻的阻值控制人流的流动规律,使电流和人流一样按一定比例选择可行的道路:同时在每条导线上串联一个较小的采样电阻,根据该电阻上的电压可求得该商区的人流量或消费需求。     

PSPICE结合MATLAB在模拟电路故障诊断中的应用研究

本文将MATLAB与PSPICE有效的结合在一起,着重通过一个模拟电路实例说明了PSPICE和MATLAB的数据通信在模拟电路故障诊断中的应用方法.实验结果表明,将PSPICE仿真所得的数据输入给MATLAB进行分析处理,能够进一步对仿真结果提取更有效的故障特征.     

基于比率法的高精度电桥电路及其应用

提出一种基于比率法的高精度电桥电路,用于测量电阻传感器中的高精度电阻。该电桥电路是基于模数转换器的数字量输出,采用模拟输入电压与参考电压比率的方法,将电桥的不平衡输出经放大后作为模数转换器的模拟量输入,将电阻式传感器相同一侧另一桥臂两端的电压差经放大后作为模数转换器的参考电压,经过模数转换后两者比率的数字量作为系统的输出。经过该电路处理后,电阻信号与系统的输出之间成线性关系,并克服了供电电压波动对电阻测量结果的影响,消除了系统的零点漂移和温度漂移。该电桥电路具有高准确度的电阻测量性能。     

A translinear circuit for sinusoidal frequency division

A translinear circuit for sinusoidal frequency division, by an integer number, is presented. The circuit uses no inductors, no capacitors, no analog multipliers and is, therefore, attractive for integration. Simulation results are included.     

High frequency characteristics of printed Cu conductive circuit

The effects of sintering temperature on microstructural evolution and electrical characteristics of screen printed Cu patterns were observed. A commercial conducting paste containing Cu nanoparticles was screen printed onto a sodalime wafer sintered under a sintering temperature range of 300 degrees C to 450 degrees C. A network analyzer and Cascade's probe system in the frequency range of 10 MHz to 20 GHz were employed to measure the S-parameters of the sintered Cu conducting patterns. From the measured S-parameters, the insertion losses in high frequencies decreased with increasing sintering temperature due to the formation of an interparticle necking after heat treatment at high temperatures. However, oxidation of Cu nanoparticles during the sintering deteriorated the RF performance of the circuits, resulting large deviation of the S-parameters from the simulated curves.     

差分跳频码性能检验研究

差分跳频是一种新的扩展频谱通信技术．在介绍差分跳频基本原理的基础上，将差分跳频的频率跳变过程建模成齐次马尔可夫链．分析了G函数的功能，重点讨论了差分跳频码性能的检验方法，包括不可约性、频隙滞留、均匀性和随机性检验，其中频隙滞留是首次提出应用于差分跳频码性能的检验．这些检验方法对于差分跳频G函数的设计具有一定的指导意义．     

LabVIEW在时间频率计量测试中的应用

介绍了一种利用LabVIEW和测量仪器中的程控功能实现对时间频率计量参数的自动测量方法,并结合LabSQL实现了数据的实时存储、分析与处理.     

Variable frequency SCR inverter with an auxiliary commutation circuit

With the recent development of static inverters using thyristors (silicon controlled rectifiers), many extensive attempts have been made to use them as adjustable frequency sources with the aim of realizing simple and accurate speed control systems of ac motors. For these applications, we have developed the improved inverter which has an auxiliary commutation circuit and a feedback current transformer. The auxiliary commutation circuit functions to improve the commutation characteristics and operation reliability, while the feedback current transformer improves the efficiency and stability. The distinguished characteristics of this new inverter have been proved by the experimental drives of induction motors and synchronous motors in wide frequency ranges.     

The application of the cryogenic system on the HTS power cable circuit in actual grid

The 22.9 kV/50 MVA AC HTS power cable system consisted of power cable with 410 m length and cryogenic system has been manufactured by LS Cable & System and installed in Icheon substation of KEPCO grid in the end of 2010. High temperature superconductor only appears the superconductivity at the constant temperate range. So in order to maintain the superconductivity, the cryogenic system is needed. The cryogenic system, the open-loop type, is consisted of the Pressure Control System (PCS), Gas/liquid separator, Circulation Pump, Decompression unit, Filter and so on. Decompression unit is a device that keeps the sub-cooled nitrogen by way of the latent heat of evaporation and includes the heat exchanger. The effectiveness-NTU method is used for the design of the heat exchanger. After installation of the cryogenic system on the site, the test of the cooling capacity of the cryogenic system and commissioning tests were performed. During the grid operation of the HTS power cable system, no major problems have been encountered to this point. The cryogenic system has been operated sufficiently to maintain a stable of the HTS power cable system. This paper will summarize the design of the cryogenic system and the results of the grid operation.