How to perform efficient sampling

abariska@student.ethz.ch wrote:

   ...

> I think the OP is faced with a signal with varying bandwidth, otherwise
> a frame-by-frame analysis makes no sense.

Pity the poor receiver! (And think how much more might be gained by 
choosing the sample rate line by line.)

Jerry
-- 
Engineering is the art of making what you want from things you can get.
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In article <y_-dnU6TlqAYHzfeRVn-jg@giganews.com>, "renaudin" <alsaeed86@gmail.com> wrote:

>**************************************************************************
>
>Thanks for the ideas,
>
>1. We can find out the effective Bandwidth with a Fourier Transform but
>this methode requires a lot of computation.
>
>2.Lowpass filter the data prior to decimation process will change its
>natural Bandwidth, which I donot want to be change.
>
>** I am Searching for a simple and efficient methode to calculate/estimate
>the natural Bandwidth of a signal.
>
>Looking forward for the discussion and ideas.
>
>Renaudin    

Estimating the signal bandwidth is very hard to do in realtime.  It is nearly 
impossible unless the signal to noise ratio is high.  In any case, you would 
have to design the system for the maximum bandwidth.

If you were going to estimate the signal bandwidth, you would likely have to 
depend on halfband filters and power detectors to determine the bandwidth.  
With a series of halfband filters, you could do a binary search to determine 
the bandwidth of the signal.  This would allow you to decimate by one-half, 
one-quarter, one-eighth, ... as appropriate for your signal bandwidth.