在Multisim 10軟件環境下，設計一種由運算放大器構成的精確可控矩形波信號發生器，結合系統電路原理圖重點闡述了各參數指標的實現與測試方法。通過改變RC電路的電容充、放電路徑和時間常數實現了占空比和頻率的調節，通過多路開關投入不同數值的電容實現了頻段的調節，通過電壓取樣和同相放大電路實現了輸出電壓幅值的調節并提高了電路的帶負載能力，可作為頻率和幅值可調的方波信號發生器。Multisim 10仿真分析及應用電路測試結果表明，電路性能指標達到了設計要求。
Abstract:
Based on Multisim 10， this paper designed a kind of rectangular-wave signal generator which could be controlled exactly composed of operational amplifier， the key point was how to implement and test the parameter indicators based on the circuit diagram. The duty and the frequency were adjusted by changing the time constant and the way of charging and discharging of the capacitor， the width of frequency was adjusted by using different capacitors provided with multiple switch， the amplitude of output voltage was adjusted by sampling voltage and using in-phase amplifier circuit，the ability of driving loads was raised， the circuit can be used as squarewave signal generator whose frequency and amplitude can be adjusted. The final simulation results of Multisim 10 and the tests of applicable circuit show that the performance indicators of the circuit meets the design requirements.
TOYFDTD1 is a stripped-down minimalist, 3D FDTD code demonstrating the basic tasks in implementing a simple 3D FDTD simulation. An idealized rectangular waveguide is modeled by treating the interior of the mesh as free space and enforcing PEC conditions on the faces of the mesh. A simplified plane wave source is inserted at one end. First released 12 April 1999. Version 1.03 released 2 December 1999.
PID calculations for the _pid structure *a. This function uses the positional form of the pid equation, and incorporates an integral windup prevention algorithim. rectangular integration is used, so this function must be repeated on a consistent time basis for accurate control.
This a very simple Yee algorithm 3D FDTD code in C implementing the free space form of Maxwell s equations on a Cartesian grid. There are no internal materials or geometry. The code as delivered simulates an idealized rectangular waveguide by treating the interior of the mesh as free space/air and enforcing PEC (Perfect Electric Conductor) conditions on the faces of the mesh.
Frequency Scale Conversion
From f To f Scale
frq2mel mel2frq mel The mel scale is based on the human perception of sinewave pitch.
frq2erb erb2frq erb The erb scale is based on the equivalent rectangular bandwidths of the human ear.
frq2midi midi2frq midi The midi standard specifies a numbering of semitones with middle C being 60. They can use the normal equal tempered scale or else the pythagorean scale of just intonation. They will in addition output note names in a character format.
LINEINTRGAL Line Integral in a 2D Vector Field.
LINEINTRGAL(X,Y,U,V,C) computes the line integral along the lines given in cell array C.
X and Y define the coordinates of a rectangular grid over which
U and V are defined. X and Y must be monotonic and 2D plaid as
％ produced by MESHGRID. X, Y, U, and V must all be the same size.
Solutions are obtained for Poissson, diffusion, or wave PDEs homogeneous or nonhomogeneous equations and/or boundary conditions rectangular, cylindrical, or spherical coordinates time, Laplace, or frequency domains Dirichlet, Neumann, Robin, singular, periodic, or incoming/outgoing boundary conditions. Output is suitable for pasting into LaTeX documents.
In this paper, a new family of Cassinian wave-guides
is proposed, simulating and calculation are finished with CST
Microwave Studio that based on Finite Integral Technique (FIT),
and some results are given. Electromagnetic field mode type of it
is TE, electromagnetic field is stronger near neck region, and
some resonance frequencies appear. The new Cassinian curve
wave-guides will possess higher power than ones of the
rectangular and elliptic wave-guides because the height at the
position where maximal electric field occurs is smaller.
法國cromda編寫的新版本MATRICE 2（矩陣和矢量運算單元）。
// ----------------------------------------------------------
// 12-01-02 : MODIFIED Matrice to Matrice2 (Delphi 6)
// All routines now operate on rectangular matrix, except (InvMat and SysLin)
// No more need to use the InitMat procedure (suppressed) :
// - the routines detect automaticaly the dimensions of matrix and vector
// - error code MatDimNul is generated if zero lines or column in matrix and vector (See DimensionMatrice and DimensionVecteur)
// - error code MatMauvDim is generated if the dimensions of matrix/vector don t allow valid result
// -
// The result matrix is dimensioned automaticaly
