Make an on-the-fly tunable-frequency periodic signal in Simulink

1 次查看（过去 30 天）

Chuong Le 2017-4-5

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/333679-make-an-on-the-fly-tunable-frequency-periodic-signal-in-simulink

My question is relating to "Repeating Sequence Interpolated" block in Simulink.

My target is building a signal which is periodically repeated with tunable frequency. As my study, "Repeating Sequence Interpolated" will work.

However, I cannot change the frequency of this block output signal on-the-fly because the block uses fixed parameter (not signal).

I decided to wrote a m file to create my function, then I pass this function to "Repeating Sequence Interpolated" block. As a result, my function is periodically repeated. That's great the frequency can be changed on the workspace, however, I still cannot change the frequency on-the-fly (simulation). I passed t, and ang to "Repeating Sequence Interpolated" block parameter.

if f == 0
    t = [0 1]';
    ang = [0 0];
else
    T = 1/f;
    fs = 44100;
    Ts = 1/fs;
    t = linspace(0, T, T/Ts + 1)';
    sample_per_half_cyc = T/Ts/2 + 1;
    u1 = linspace(-pi/2, pi/2, sample_per_half_cyc);
    u2 = linspace(pi/2, -pi/2, sample_per_half_cyc);
    u2(1) = [];
    u = [u1 u2];
    dif = length(t) - length(u);
    ang = cat(2, u, -pi/2*ones(1,dif));
end