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Oversampling algorithm for root raised cosine pulse shaping filter

Started by chowash June 29, 2005
hello !

I am working on a design of a Root Raised Cosine Pulse Shaping Filter and
my design of filter taps are on the basis of sampling frequency which is
of 4 times the BB frequency. Now to use this filter in the Tx section, I
need to oversample my input data by 4 times. I would like to have a
suggestion from you regarding the type of Oversampling Algoirthm that I
can use for this purpose.



		
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"chowash" <chowmee1410@yahoo.com> wrote in message
news:nq6dnQSaw98gOF_fRVn-jQ@giganews.com...
> hello ! > > I am working on a design of a Root Raised Cosine Pulse Shaping Filter and > my design of filter taps are on the basis of sampling frequency which is > of 4 times the BB frequency. Now to use this filter in the Tx section, I > need to oversample my input data by 4 times. I would like to have a > suggestion from you regarding the type of Oversampling Algoirthm that I > can use for this purpose.
The most common method for this kind of oversampling is to use sinc interpolation to get the 4x oversampled data. Of course, there are plenty of other techniques, but this is what I've seen in my limited experience for these applications. Cheers Bhaskar
> > > > > This message was sent using the Comp.DSP web interface on > www.DSPRelated.com

chowash wrote:
> hello ! > > I am working on a design of a Root Raised Cosine Pulse Shaping Filter and > my design of filter taps are on the basis of sampling frequency which is > of 4 times the BB frequency. Now to use this filter in the Tx section, I > need to oversample my input data by 4 times. I would like to have a > suggestion from you regarding the type of Oversampling Algoirthm that I > can use for this purpose. > > > > > This message was sent using the Comp.DSP web interface on > www.DSPRelated.com
I like this solution: http://www.dspguru.com/comp.dsp/tricks/dsn/firintrp.htm John
Basically, 'Sinc' is the result of Low-Pass-filtering which suppresses the
image in frequency domain that has been created by zero-padding.
So it is pretty theoretically ok as long as the filter tap length is long
enough. And unquestionably, long filter tap causes long delay and also
consumes more memory resource, sometimes, linear interpolation is also
used. Also try to search for some high order approximation that has better
performance in passing band-ripple (by sacrificing stop band suppression.)
And also, try to think about trade-offs between passband ripple and
stopband suppression.




>"chowash" <chowmee1410@yahoo.com> wrote in message >news:nq6dnQSaw98gOF_fRVn-jQ@giganews.com... >> hello ! >> >> I am working on a design of a Root Raised Cosine Pulse Shaping Filter
and
>> my design of filter taps are on the basis of sampling frequency which
is
>> of 4 times the BB frequency. Now to use this filter in the Tx section,
I
>> need to oversample my input data by 4 times. I would like to have a >> suggestion from you regarding the type of Oversampling Algoirthm that
I
>> can use for this purpose. > >The most common method for this kind of oversampling is to use sinc >interpolation to get the 4x oversampled data. >Of course, there are plenty of other techniques, but this is what I've
seen
>in my limited experience for these applications. > >Cheers >Bhaskar > >> >> >> >> >> This message was sent using the Comp.DSP web interface on >> www.DSPRelated.com > > >