what type of mean(average) is taken...

[Nosheen]

hi there...
can anyone help me in answering that what type of mean(average) is taken in selecting a center(carrier) frequency in the entire AM (audio frequency band) at which sampling can be performed for extracting a particular channel(radio frequency channel)...

i'll be highly greatful if someone helped me in...

 

[brmadhukar]

You do not take a mean -- You gradually lock into it.

BRMadhukar

 

[m_llaa]

Hi
You r not clear, but if you work in frequency domain and FFT, you should just take sample mean to predict your carrier frequency.
But it is not the method, using PLL is better.

 

[Nosheen]

well m working in fequency domain and FFT.but how wod i get the sample mean..moreover the problem arises when my bandwidth iz also varying.
How wod i get the center frequency(as carrier) then for extracting my information...
And secondly how Phase Lock Loop help me extract the required freq band by using appropriate carrier frequency.
thanx
Regardz
Nosheen

 

[m_llaa]

Hi Nosheen
Do you see Carlson's book? I think this book can help you.
About your first question, if your FFT vector has N points, you can add M vectors and devide it to M for averaging. Choosing proper M and N is depend on you and some other points in your design and processing.