A Computer-On-Module, or COM, is a Module with all components necessary for a bootable host computer, packaged as a super component. A COM requires a Carrier Board to bring out I/O and to power up. COMs are used to build single board computer solutions and offer OEMs fast time-to-market with reduced development cost. Like integrated circuits, they provide OEMs with significant freedom in meeting form-fit-function requirements. For all these reasons the COM methodology has gained much popularity with OEMs in the embedded industry. COM Express® is an open industry standard for Computer-On-Modules. It is designed to be future proof and to provide a smooth transition path from legacy parallel interfaces to LVDS (Low Voltage DIFFERENTIAL Signaling) interfaces. These include the PCI bus and parallel ATA on the one hand and PCI Express and Serial ATA on the other hand.
上傳時間： 2013-11-05
上傳用戶：Wwill
Single-Ended and DIFFERENTIAL S-Parameters DIFFERENTIAL circuits have been important incommunication systems for many years. In the past,DIFFERENTIAL communication circuits operated at lowfrequencies, where they could be designed andanalyzed using lumped-element models andtechniques. With the frequency of operationincreasing beyond 1GHz, and above 1Gbps fordigital communications, this lumped-elementapproach is no longer valid, because the physicalsize of the circuit approaches the size of awavelength.Distributed models and analysis techniques are nowused instead of lumped-element techniques.Scattering parameters, or S-parameters, have beendeveloped for this purpose [1]. These S-parametersare defined for single-ended networks. S-parameterscan be used to describe DIFFERENTIAL networks, but astrict definition was not developed until Bockelmanand others addressed this issue [2]. Bockelman’swork also included a study on how to adapt single-ended S-parameters for use with DIFFERENTIAL circuits[2]. This adaptation, called “mixed-mode S-parameters,” addresses DIFFERENTIAL and common-mode operation, as well as the conversion betweenthe two modes of operation.This application note will explain the use of single-ended and mixed-mode S-parameters, and the basicconcepts of microwave measurement calibration.
上傳時間： 2014-03-25
上傳用戶：yyyyyyyyyy
為了在CDMA系統中更好地應用QDPSK數字調制方式，在分析四相相對移相（QDPSK)信號調制解調原理的基礎上，設計了一種QDPSK調制解調電路，它包括串并轉換、差分編碼、四相載波產生和選相、相干解調、差分譯碼和并串轉換電路。在MAX+PLUSⅡ軟件平臺上，進行了編譯和波形仿真。綜合后下載到復雜可編程邏輯器件EPM7128SLC84-15中，測試結果表明，調制電路能正確選相，解調電路輸出數據與QDPSK調制輸入數據完全一致，達到了預期的設計要求。 Abstract: In order to realize the better application of digital modulation mode QDPSK in the CDMA system， a sort of QDPSK modulation-demodulation circuit was designed based on the analysis of QDPSK signal modulation-demodulation principles. It included serial/parallel conversion circuit, DIFFERENTIAL encoding circuit, four-phase carrier wave produced and phase chosen circuit, coherent demodulation circuit, difference decoding circuit and parallel/serial conversion circuit. And it was compiled and simulated on the MAX+PLUSⅡ software platform,and downloaded into the CPLD of EPM7128SLC84-15.The test result shows that the modulation circuit can exactly choose the phase，and the output data of the demodulator circuit is the same as the input data of the QDPSK modulate. The circuit achieves the prospective requirement of the design.
上傳時間： 2013-10-28
上傳用戶：jyycc
Calculation of the DIFFERENTIAL Impedance of Tracks on FR4 substrates There is a discrepancy between calculated and measured values of impedance for DIFFERENTIAL transmission lineson FR4. This is especially noticeable in the case of surface microstrip configurations. The anomaly is shown tobe due to the nature of the substrate material. This needs to be considered as a layered structure of epoxy resinand glass fibre. Calculations, using Boundary Element field methods, show that the distribution of the electricfield within this layered structure determines the apparent dielectric constant and therefore affects theimpedance. Thus FR4 cannot be considered to be uniform dielectric when calculating DIFFERENTIAL impedance.
上傳時間： 2013-10-18
上傳用戶：masochism
用JAVA語言編寫，包括PSO（Particle swarm optimization, 中文譯名為粒子群優化或微粒群算法), DE (DIFFERENTIAL evolution, 中文譯名為差分進化或差異演化)等算法，有一些不帶約束和帶約束的算例（如Michelawicz的幾個問題）。使用說明見usage.txt、RUNExample.bat和程序中的注釋。
上傳時間： 2014-01-06
上傳用戶：agent
The purpose of this application note is to describe the main elements of an RS-422 and RS-485 system. This application note attempts to cover enough technical details so that the system designer will have considered all the important aspects in his data system design. Since both RS-422 and RS- 485 are data transmission systems that use balanced DIFFERENTIAL signals, it is appropriate to discuss both systems in the same application note. Throughout this application note the generic terms of RS-422 and RS-485 will be used to represent the EIA/TIA-422 and EIA/TIA-485 Standards.
標簽： application describe elements purpose
上傳時間： 2013-12-29
上傳用戶：sxdtlqqjl
CLAWPACK is a software package designed to compute numerical solutions to hyperbolic partial DIFFERENTIAL equations using a wave propagation approach
標簽： hyperbolic numerical solutions CLAWPACK
上傳時間： 2014-01-03
上傳用戶：woshini123456
matlab 求解微分方程 ，This module Does FEM analysis of a field problem when the Governing DIFFERENTIAL equation
上傳時間： 2016-06-02
上傳用戶：二驅蚊器
數值分析算法源碼(java) 這個學期一邊學習java一邊學習數值分析,因此用java寫了一個數值分析算法的軟件包numericalAnalysis. [說明] 適合使用者:會java的,想要學習數值分析算法的人. 本代碼對照書:數值分析第二版,史萬明等編,北京理工大學出版社. 本代碼盡量按書中描述的來寫,可以提供參考. [使用方法] 在java的ide中新建一個項目,把numericalAnalysis包直接拷貝到此項目的源文件夾中,然后要解決什么問題,就相應的編譯運行什么包. 另外有這些類的API提供參考,可以自己根據自己要求寫驅動類.運行API文件夾中的index.html文件就行. [包的結構] numericalAnalysis包中又含有9個包,除function包的是接口外,其余包都含有一個獨立的數值分析問題的類以及其驅動類.9個包如下: DIFFERENTIAL:微分問題 equation:方程 function:只含一個接口,用來讓用戶寫自己的函數 functionApproximation:離散情況下函數逼近問題 integration:積分問題 interpolation:插值問題 linearEquationGroup:線性方程組問題(包括過定方程組) norm:求解向量和矩陣的范數 ode:常微分方程數值解的求解
標簽： java numericalAnalysis 數值分析 算法
上傳時間： 2014-01-04
上傳用戶：wff
Toolbox for Numerical Computing with MATLAB （by Cleve Moler). Numerical Computing with MATLAB （by Cleve Moler) is a textbook for an introductory course in numerical methods, Matlab, and technical computing. The emphasis is on in- formed use of mathematical software. We want you learn enough about the mathe- matical functions in Matlab that you will be able to use them correctly, appreciate their limitations, and modify them when necessary to suit your own needs. The topics include * introduction to Matlab, * linear equations, * interpolation, * zero and roots, * least squares, * quadrature, * ordinary di?erential equations, * random numbers, * Fourier analysis, * eigenvalues and singular values, * partial DIFFERENTIAL equations.
標簽： Numerical Computing MATLAB with
上傳時間： 2014-01-01
上傳用戶：guanliya
