How to generate continuous time domain signal with different start and end time?

I am trying to generate 8 signals with 8 different frequencies. Each signal have same total time period. And each signal start at different time. Second signal starts at end of the first signal and so on. I want to do it in loop so that I don’t have to write repetitive instructions for all 8 signals. So how can I do it ?

Answer 1

[Paul]

By "continuous time domain signal" do you mean signal defined symbolically (otherwise, I'm not sure what's meant by "continuous"). If so, then

w = sym([1 2 3]); % example with three frequencies
syms t
totaltime = 2; % for example
pw = piecewise(0 < t <= totaltime, sin(w(1)*t));
for ii = 2:numel(w)
pw = piecewise((ii-1)*totaltime < t <= ii*totaltime, sin(w(ii)*t),pw);
end
pw

pw = 

fplot(pw,[0 6])

Is there supposed to be a continuity constraint at the transition points?

[Omkar Vaze]

fs=f_t*20; %Sampling frequency

Ts=1/fs; %Sample time

I have frist signal with time and frequency as below:

T=0:Ts:(0.667e-3)-Ts; %Time period of signal starting at zero and end at (0.667e-3).

x1=cos(2*pi*f_actual1(3,1)*T); %signal with frequency 1

Now, the second signal have time period (0.667e-3) but start time is at (0.667e-3) and end time is (1.333334e-3).

Similarly I have 8 more signals. So how I can do this without retyping the instructions?

[Paul]

Using some made up data because not all was supplied. One way to do this:

f_actual = (1:8)*50; % frequencies
nsignals = numel(f_actual);
duration = 2/3*1e-3;
samplespersignal = 100;
Ts = duration/samplespersignal;
npts = samplespersignal*nsignals;
t = (0:(npts-1))*Ts;
t = reshape(t,samplespersignal,[]);
s = cos(2*pi*f_actual.*t);

% plot each signal individually
plot(t,s)

% combine into a single signal
plot(t(:),s(:))