how can I find the delay between two seperate sine waves

Status
Not open for further replies.

keremcant

Member level 5
Joined
Dec 25, 2009
Messages
87
Helped
6
Reputation
12
Reaction score
5
Trophy points
1,288
Activity points
1,910
I am pulsing an transducer with an FPGA board and I get both the pulse signal and an echo of it after some time. the pulse I am using is a combination of three sine waves. I want to measure the delay between the pulse itself and the echo. how can I do it? probably I will have to compare the signals, but how?
 

hmm...

cross correlation would be a good approach but correlating sine waves, might not be the best thing as you'll get multiple-peaks.

But I think it will give a decent enough approximate.


Why don't you sent a pn sequence?
 

Why don't you sent a pn sequence?
Click to expand...
May be an option, the original poster should clarify the requirements. I was already wondering what's the purpose of a "combination of three sine waves".

I guess it's a small band (e.g. US) transducer, having a sine burst as impulse response anyway. And the intention is to achieve a time resolution of a fraction of the self resonance period. Ambiguousity is then a general problem, not only specific to cross-correlation. The stimulation must be carefully designed, e.g. a phase-keyed or small-band chirp signal. Possibly the threefold sine has a similar purpose.
 
Status
Not open for further replies.

Similar threads

Menu
Log in
Register
Cookies are required to use this site. You must accept them to continue using the site. Learn more…