Thanks for the reply, pancho_hideboo.
Well, I found the same webpage you sent from Wikipedia, but I've read few articles that differentiate the two, without explaining how.
My understanding is :
for a complex signal x(t),
PAPR = max(x(t).x*(t))/E(x(t).x*(t))
As an example, if x(t)= sin(2.pi.f.t) - a real valued signal, PAPR=2 (linear) - doing the math!
The 'E' is the expected value function.
http://en.wikipedia.org/wiki/Expected_valueAnd going by the same wikipedia page, crest factor of x(t)= sin(2.pi.f.t) is √2. i.e. crest factor = √papr.
Maybe crest factor deals with voltages and papr deals with power, because in the dB scale, they're both 3.01dB for a sine wave. I just need someone to clarify it with details!
Regarding multi-carrier PAPR, I read the same about 10log(Nc) not being applicable for WCDMA (multi-carrier), but without any explanation. Would you know why?
If it is due to the spread spectrum, how is different from OFDM-LTE? Because, beyond a certain number of carriers, OFDM has the same treatment as gaussian noise.
I find an alarming number of articles that use terms like 'carrier' (as opposed to modulated carrier or subcarrier) and 'crest factor' (as opposed to PAPR), very loosely, hence my confusion.
-sandman.