基于LPT的多路输入板的设计

介绍基于ISA总线的输入板的设计,对单片机扫描按键状态,通过并行打印口和上位机通讯的输入板做了详细的设计分析,包括硬件设计和软件设计的分析。     

计算机绘制军用地图程序系统SJ84

一、系统SJ84的功能和特点 1.数据键盘输入与图形数宇化方法把一幅军用地图输入计算机,一般有三种方法: 1) 采用图形输入板:人在输入板上描画,地图数字化后进入内存。     

医学图形计算机辅助分析系统

本文对采用脉冲感应技术为图形输入手段的微机辅助分析系统,从软硬件设计、脉冲感应图形输入板基本原理、性能与结构、实现作图及检测的过程和方法、开发应用软件等方面作了描述。系统以电磁感应笔或游标为传输数据媒质,在汇编软件支持下,简便地实现了二维图形的输入问题。为进一步探讨分析医学研究中的图形问题提供了一个可靠、灵活的工具。     

电力直流系统监控模块的研制

根据电力直流系统的特点和要求,设计了以嵌入式ＰＣ为核心,扩展了多串口板、开关量输入板、开关量输出板、模拟量采集模块的监控模块,软件具有强大的组态能力,并具有专家系统的功能,可能实现蓄电池智能管理和其他各种监控功能,与后台监控通讯,可以实现电力直流系统的集中监控和“四遥”功能。     

收费输入法真的靠谱吗？

我们都知道在iOS系统中,不越狱是无法安装第三方输入法的。而iOS的自带输入法又不能满足所有人的要求,比如笔者身边就总有些朋友希望能够用上九宫格布局的输入法。于是搜狗推出了《搜狗输入板》,采取在输入板内打字再复制出来粘贴的策略。虽然不是很理想,不过由于是免费的,所以笔者认为也还可以接受。     

写出的WACOM2000大礼

个性化的签名、中国的水墨画等都在电脑屏幕上轻松的用“笔”绘出,这是笔者1月10日,在京召开的日本“WACOM 2000大礼盒”新闻发布会上见到的。WACOM 2000大礼盒是为我国家庭教育市场设计的一款产品组合,包括输入板、输入笔各一只和三张光盘,光盘软件含绘画、照相加工、三维美术字设计、电子相册以及汉字手写识别和手写电子邮件的5个软件,以及 Photoshop、Painter     

感兴趣区的图象放大

本文提出了一种感兴趣图象放大的新算法。这种算法解决了任何形状的感兴趣区的图象插值放大的问题,适用于用图形输入板、计算机作图和用边界跟踪方法获取的闭合曲线内的图象放大。本文还给出了放大实例。     

论数字化仪的安装与配置

AutoCAD软件包是由美国Autodesk司开发的一个很实用的计算机辅助设计软件包,目前在我国微机上得以广泛的应用,其中数字化仪作为光标定标设备用于Au-toCAD,现已成为AUTOCAD的不可缺少的设备之一.MOUSE是以在专用的台面上移动的方式工作的,移动鼠标时,光标则在屏幕上跟着它移动,这样就可以直接在屏幕上进行光标定位,也可以通过Mouse 按钮标定菜单的选择项,MOUSE在AUTOCAD中工作起来比键盘更加方便,而数字化仪的工作方式与Mouse相似,在图形输入板上移动铁笔式游标,就可以完成Mouse的工作,但是,图形输入板还提供了其它的定标设备所不具备     

NT启动超小型设备

在过去的一年中,PC制造商一直在不断地将Micmsoft公司的Windows NT操作系统植入到他们的高端笔记本PC系统中。而现在,这一企业级的操作系统正在谋求进入更小尺寸的设备中,例如基于笔式输入板的PC     

用鼠标“写”汉字

不少软件开发商一直致力于手写输入系统的研制与开发,其产品在硬件方面都离不开输入板和手写笔等附加设备。对此,北大方正新近推出了用鼠标直接在桌面上书写的“手易手写联想输入系统”。我们试用后,认为其优点是构思较独特。     

Miniaturized multi‐frequency Wilkinson power dividers based on nonuniform coplanar waveguide

In this work, the design of miniaturized dual‐ and triple‐ frequency Wilkinson power dividers using nonuniform coplanar waveguides is presented. The miniaturized configurations are achieved by replacing the conventional uniform arms with their equivalent multi‐frequency nonuniform transmission lines. The nonuniform width variation is governed by a truncated Fourier series expansion with coefficients optimized to obtain the desired multi‐frequency operation. The optimization process is carried out through the analysis of the even/odd mode circuits. The proposed dividers are simulated, fabricated, and measured to validate the design methodology. Simulated and measured results agree very well, and show input/output ports return loss and isolation better than 14.4 dB and transmission parameters in the range of ?3 ± 2 dB at the design frequencies. Size reduction of 16.7% and 17.6% are achieved for the fabricated dual‐ and triple‐frequency dividers, respectively.     

核心路由器千兆以太网线卡输入数据的分路设计与实现

千兆以太网线路接口卡是高速路由器中实现与外部链路连接的重要模块,本文介绍了其主要功能,给出一种基于FPGA和CAM实现的输入报文数据流分路处理方案和CAM维护软件的设计方法。测试结果表明,该设计方案可以很好地实现对10端口千兆以太网接口线速处理的支持。     

LTE-A空口监测仪下行基带板的可行性分析

针对国内研制出的多类仪器仪表中基带板的设计仅限于通过实现来验证其可行性的问题,提出在基带板设计之前对可行性进行分析,防止在实现时芯片资源不足而导致人力和时间等资源的浪费,同时为增强型长期演进空口监测仪中基带板的设计提供参考。根据增强型长期演进特性以及监测仪需求确定核心处理器的选型;重点对基带板上存储器的存储能力和总线能力进行分析,确保所选的元器件有足够的能力并留有一定的余量;最终通过在基带板上的测试证明该可行性分析的正确性,也为其他的硬件芯片选型提供参考。     

Analysis and design of packaged and ESD protected BiCMOS RF front‐end for a UHF receiver

The design of packaged and ESD protected RF front‐end circuits for UHF receiver working at ISM band is presented. By extensively evaluating the effects of the package and ESD parasitics on the LNA input impedance, transconductance, and noise figure, some useful guidelines on the design of inductively degenerated common emitter LNA with package and ESD protection are provided. In addition, by taking advantage of both the bipolar and MOSFET devices, a BiFET mixer with low noise and high linearity is also described in this article. With the careful consideration of the tradeoffs among noise figure, linearity, power gain, and power consumption, the front‐end is implemented in a generic low‐cost 0.8‐μm BiCMOS technology. The on‐board measurement of the packaged RF front‐end circuits demonstrates a 20.3‐dB power gain, 2.6‐dB DSB noise figure, and ?9.5‐dBm input referred third intercept point while consuming about 3.9‐mA current. © 2007 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2007.     

基于OWPB和LS-SVM的电路板故障诊断系统

针对雷达电路板检修困难的问题,提出了基于最优小波包基和最小二乘支持向量机相结合的雷达电路板故障诊断方法。利用小波变换对采样数据进行去噪处理,通过小波包分解选择最优小波包基提取熵值作为故障特征向量,并作为基于最小二乘支持向量机的雷达故障诊断模型的输入向量,经诊断模型输出后,完成雷达电路板故障诊断。基于此方法设计了雷达电路板故障诊断系统,提高了雷达故障诊断的正确性和效率。     

Adaptive tracking control of MIMO nonlinear nonminimum phase system with unknown input nonlinearity

This paper proposes a nonlinear adaptive control for output tracking of multi‐input multi‐output nonlinear nonminimum phase system with input nonlinearity. The parameters of the input nonlinearity are assumed to be unknown. This problem is challenging, not only because of the unstable internal dynamics of nonminimum phase system, but also the existence of the unknown input nonlinearity. The partially linearized model of the original system is obtained through input/output linearization, and a states tracking model is constructed based on the computed ideal internal dynamics. A nonlinear adaptive controller, which can guarantee the bounded of output tracking error in the existence of unknown input nonlinearity, is proposed. Finally, a numerical simulation on vertical takeoff and landing aircraft is given to show the effectiveness of the proposed control methods.     

Wideband MIMO handset antenna design based on theory of characteristic modes

A novel multi‐input multi‐output (MIMO) antenna array in a compact mobile handset has been designed to operate in a wide frequency band below 1 GHz. Based on theory of characteristic modes (TCM), a pair of parallel folding metal strips is introduced to make a chassis generate two orthogonal eigenmodes with wideband resonant characteristics. A meander line‐loaded monopole structure is employed to excite higher frequency eigenmode, and a parallel lumped L‐C structure is used to excite lower frequency eigenmode. With two proposed feeding structures, the proposed MIMO antenna array can operate in a wide frequency band covering 745‐960 MHz with an envelope correlation coefficient (ECC) <0.12. Simulation and measurement results demonstrate that the proposed MIMO antenna array has total efficiency better than 40% over the whole operating band.     

基于以太网的多串口数据采集系统及应用

提出了一种基于工业以太网的多串口现场数据采集系统.该系统核心是由微处理器MCF5307控制的具有多个RS232接口和一个RJ45以太网接口的数据采集板,它能够通过串行口对数个监控对象进行并行数据采集,同时提供了以太网联网能力,实现了计算机远程监控.也介绍了处理器和通讯芯片的硬件连接设计和基本软件执行流程.     

智能交通系统中的人机界面设计*

为实现智能交通系统中人与机器之间的灵活交互,分析人机界面的功能,详细介绍了智能交通系统中基于多平台的人机界面的设计过程。阐述了ARM-uClinux系统软件构架以及如何在进程间传递信息以实现多进程协调工作。设计了基于短消息服务人机交互方法。鉴于Web服务的广泛性,提出了Web服务作为另一种交互平台,在智能交通人机界面应用的可行性和实现方法。试验结果证明,基于多平台的人机界面的可靠性,并可以改善智能交通系统的服务。     

Design,analysis, and modeling of miniaturized multi‐band patch arrays using mushroom‐type electromagnetic band gap structures

Novel designs of miniaturized multi‐band 1 × 2 patch antenna array with electromagnetic band gap (EBG) for wideband operation are presented in this article. The proposed patch array is composed of three unequal arms fed by CPW‐to‐slotline transitions to widen the impedance bandwidth with multiple resonances. By adding two conventional mushroom‐type EBG (CMT‐EBG) structures on both sides of 100 Ω slotline transitions, the compact wideband patch array (first design) is obtained. This proposed design with CMT‐EBG includes two bands with the measured ranges (S₁₁ ≤ ?10 dB) of 6.65‐6.95 GHz (C‐band) and 8.57‐11.53 GHz (X‐band). Moreover, the proposed 1 × 2 patch array with the 3 × 3 CMT‐EBG array on the one side of the structure (second design) operates at multi‐bands with the measured ?10 dB impedance bandwidths of 5.80‐5.98 GHz, 6.25‐6.47 GHz, and 8.48‐11.52 GHz. The second design compared to the first design introduces a considerable size reduction with more resonance tuning capability. The performance of the proposed designs is analyzed based on the EBG band gap properties near the slotline transitions. These designs with the EBGs indicate prominent features like resonance tuning capability, acceptable miniaturization, and enhanced impedance bandwidth with low‐fabrication cost. In this study, an equivalent circuit model of the proposed first design with EBG is also offered to describe the properties of multi‐band operation.