# plot a stepped frequency singal

3 views (last 30 days)
ting po chun on 2 Jul 2023
Commented: Sam Chak on 3 Jul 2023
Hi,
I want to plot a stepped frequency singal (like the picture)
(Time during 0 to 1 sec)
ting po chun on 3 Jul 2023
@Sam Chak Thank you very much, but I still don't know the define of R,c is the speed of wave. Suppose I change Beta is it possible to make the attached image look like?
Sam Chak on 3 Jul 2023
There are many missing info. As a person from this research field, you know the formula of the frequency, yet you don't know what R and c are. There must be a reference book, textbooks, or journal papers that show the frequency formula. So, I'm unsure how it will work out for you. For example, even if I provide a math function by guessing, you are unable to feed the values of R and c into the given math function.
Would it be more effective if you just search the math function from the literature?
Thus, I'm wondering, you accidentally produced such periodic pattern. Now, you want to identify its math function. Are you searching for a general math function that produces such periodic pattern (not the exact signal)? Or, a perfect math function with the known values of the parameters ?
How many cycles in the following time intervals?
• between 0 and
• between and
• between and
• between and
• between and

Sara Boznik on 2 Jul 2023
Hi,
if you dont have specific function, you can do simple step function like below:
t = linspace(0, 1, 1000); % This defines the time scale in the plot
f = @(t) [(t > 1) - (t > 0.5)] + [(t > 0) - (t > 0.5)];
stairs(t, f(t));
Hope it help.
ting po chun on 2 Jul 2023
@Sara Boznik i do'nt know the real function but i found a function maybe refer to.
f=(-2Rβ)/cτ
f is frequency-domain, chirp of bandwidth β and pulse width τ
Tnank you!