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Homework Help: Frequency domain conversion

  1. Feb 6, 2009 #1
    1. The problem statement, all variables and given/known data

    Dear all ,

    Am new to matalb and am having some couple of problems. i want to convert the following wave form from time to frequency domain .

    I have made conversion by using integration by parts.Please find the matlab attached files.

    ACos(ωt+φ)*exp(-jωt) , limit [0,T]

    2. For T=n*pi/2ω where n= odd, how to generate odd values of "n".

    3. Graph
    When ever i try to plot a graph between Amplitude and Time , it generates error or when ever i plot a graph between two variable values e.g
    T 1:45;
    Pi 0:360;
    "??? Error using ==> mtimes
    Inner matrix dimensions must agree."

    2. Relevant equations

    3. The attempt at a solution
    T=n*pi/2w where w= omega
    function L=laser()
    %T=n*pi/2w where w= omega
    phi= 0:360;
    T=45;% just used to plot a graph

    L= (-cos(phi)*w*sin(w*T)*exp(-j*w*T))+(w*cos(phi))-sin(phi)*(w*cos(w*T)*exp(-j*w*T)-w+ (w^2)*sin(w*T)*exp(-j*w*T)/(1+w^2))
    subplot(1,1,1), plot(phi,L);

  2. jcsd
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