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  1. #1
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    qam matlab

    Hi,I am trying to design the timing recovery loop in the QAM demodulator.If i have finished the algorithm design of the loop,then how can i verify my design in the matlab/simulink?How can i get the proper input I/Q data and the right output data,which can be used to verify my verilog implementation?
    Thanks!

  2. #2
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    matlab qam

    1) generate input I/Q data in MATLAB
    2) read this data in simulator (Modelsim, Aldec, etc.)
    3) save output data of your design in simulator
    4) compare the output data of hdl design and MATLAB model

    Aldec and Modelsim also can work with MATLAB directly, but i don't know how



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  3. #3
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    qam simulink

    How to generate the proper I/Q data and set the matlab simulation model?
    That is to say,how to verify my algorithm ?
    That is critical.


    1 members found this post helpful.

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  4. #4
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    16 qam matlab

    for example, the simulink demos:
    Rayleigh Fading Channel generate the qpsk I/Q signals

    you can to convert this demos to qam I/Q signal generator



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  5. #5
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    qam matlab code

    Quote Originally Posted by mhytr
    How to generate the proper I/Q data and set the matlab simulation model?
    u can use the Random integer generator block in the simulink to generate random pulses for the QAM signal. then u can use the doppler block and the AWGN channel for generating the real QAM modulated signals. Verify ur I/Q outputs using the Discrete-Time Scatter plots.



  6. #6
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    16qam matlab

    echo on
    K=10;N=2*K;T=100;
    a=rand(1,36);
    a=sign(a-0.5);
    b=reshape(a,9,4);
    % Generate the 16QAM points
    XXX=2*b(:,1)+b(:,2)+j*(2*b(:,3)+b(:,4));
    XX=XXX';
    X=[0 XX 0 conj(XX(9:-1:1))];
    xt=zeros(1,101);
    for t=0:100
    for k=0:N-1
    xt(1,t+1)=xt(1,t+1)+1/sqrt(N)*X(k+1)*exp(j*2*pi*k*t/T);
    echo off
    end
    end
    echo on
    xn=zeros(1,N);
    for n=0:N-1
    for k=0:N-1
    xn(n+1)=xn(n+1)+1/sqrt(N)*X(k+1)*exp(j*2*pi*n*k/N);
    echo off
    end
    end
    echo on
    pause % press any key to see a plot of x(t)
    plot([0:100],abs(xt))
    % Check the difference between xn and samples of x(t)
    for n=0:N-1
    d(n+1)=xt(T/N*n+1)-xn(1+n);
    echo off
    end
    echo on
    e=norm(d);
    Y=zeros(1,10);
    for k=1:9
    for n=0:N-1
    Y(1,k+1)=Y(1,k+1)+1/sqrt(N)*xn(n+1)*exp(-j*2*pi*k*n/N);
    echo off
    end
    end
    echo on
    dd=Y(1:10)-X(1:10);
    ee=norm(dd);



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  7. #7
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    modulacion qam matlab

    Hello,
    Can anyone plz explain, how this formula works,
    XXX=2*b(:,1)+b(:,2)+j*(2*b(:,3)+b(:,4));
    What is the idead behind using this fromula to generate 16 QAM.
    thankyou.



  8. #8
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    qam simulation using matlab

    i need it too



  9. #9
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    qam simulation

    hi ashay.deshpande
    XXX=2*b(:,1)+b(:,2)+j*(2*b(:,3)+b(:,4));
    is same as
    for (i=0;i<size of b array;i++)
    XXX+=2*b(i,1)+b(i,2)+j*(2*b(i,3)+b(i,4));

    so : implies all the values in an array



  10. #10
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    matlab qam signal

    i also want 2 know how simulations of QAM r done



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