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pwlresp

Calculate time response of piecewise linear input signal

    Description

    [tran,t] = pwlresp(h,signalTime,signalValue,tsim) computes the time response, tran, and time vector, t, of a piecewise linear input signal. The time response is calculated for a rational or rfmodel.rational object, h, using the signal parameters, signalTime and signalVlaue, over the simulation time, tsim.

    example

    [tran,t] = pwlresp(h,signalTime,signalValue,tsim,tper) computes the time response for the period of the input signal, tper.

    [tran,t] = pwlresp(h,signalTime,signalValue,tsim,tper,flag) computes the time response across a set of time points that speed up the time response computation.

    Note

    Use the flag input argument only for periodic signals. When you use the flag input, the first element of tsim vector should be 0.

    Examples

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    Calculate the transient output waveform when a piecewise linear input signal is applied to a system described using a rational object.

    Perform Rational Fit

    Read the specified S2P data file.

    S = sparameters('passive.s2p');
    freq = S.Frequencies;

    Convert the S-parameters of the two-port network to a transfer function and fit to a rational object.

    tf_data = s2tf(S);
    h = rational(freq,tf_data);

    Define Parameters of Periodic Input Signal

    Define the parameters of a periodic input signal over its first period, tper.

    signalTime = [0,0.1,0.6,0.7,1.5]*1e-9;
    signalValue = [0,5,5,0,0];
    tper = 1.5e-9;

    Calculate and Plot Transient Response

    Calculate the transient response over three time periods for the simulation time interval, ts.

    ts = 2e-11;
    tsim = 0:ts:3*tper;
    [tran,t] = pwlresp(h,signalTime,signalValue,tsim,tper);

    Plot the output response and the periodic input signal.

    vin = repmat(signalValue,1,3);
    tin = [signalTime,signalTime+tper,signalTime+2*tper];
    figure
    plot(tin*1e9,vin,t*1e9,tran,'LineWidth',2)
    axis([0 4.5 -2 6.2]);
    xlabel('Time (ns)');
    ylabel('Input Signal and Response (v)');
    legend('Input','Resp');

    Figure contains an axes object. The axes object contains 2 objects of type line. These objects represent Input, Resp.

    Input Arguments

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    Rational fit object, specified as either an rfmodel.rational or a rational object.

    Input signal time, specified as a vector in seconds.

    Input signal amplitude, specified as a vector. The signal amplitude corresponds to the input signal time specified in signalTime.

    Note

    For a periodic input signal, specify the signalValue over only to the first period of the signal.

    Simulation time, specified as a vector in seconds.

    Period of the input signal, specified as a positive scalar in seconds.

    Flag to speed up the time response computation, specified as 'Rapid'. Use the flag argument for the function to rapidly compute the time response.

    Note

    When you specify flag as an input argument to this function, the time vector, t corresponding to the output response ,tran, might be different from the simulation time tsim specified.

    Output Arguments

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    Output response of a piecewise linear input signal, returned as a vector.

    Time vector corresponding to the output response, tran, returned as a vector.

    Introduced in R2021a