Interpolation

Hi Friends,

I hav a signal(time_domain). 80ms/s. Sample distance = 12.5ns. I wana
interpolate by factor 6.

Wht should i use, interpolation filter?

Amrish.

amrish wrote:
> I hav a signal(time_domain). 80ms/s. Sample distance = 12.5ns. I wana
> interpolate by factor 6.
> 
> Wht should i use, interpolation filter?
> 

No offense intended, but you should consider doing your own homework. If 
you don't have a textbook, I like Oppenheim and Schafer, but others have 
other opinions.

What is the application of this filter? What is more important: SNR, 
bandwidth or performance? How much data do you have? You need the 
answers to these questions before you find a solution to a real world 
problem.

There are many types of interpolation filters which would be suitable. 
Which you choose depends on the details of the application.

Regards

Marc Brooker

>amrish wrote:
>> I hav a signal(time_domain). 80ms/s. Sample distance = 12.5ns. I wana
>> interpolate by factor 6.
>> 
>> Wht should i use, interpolation filter?
>> 
>
>No offense intended, but you should consider doing your own homework. If

>you don't have a textbook, I like Oppenheim and Schafer, but others have

>other opinions.
>
>What is the application of this filter? What is more important: SNR, 
>bandwidth or performance? How much data do you have? You need the 
>answers to these questions before you find a solution to a real world 
>problem.
>
>There are many types of interpolation filters which would be suitable. 
>Which you choose depends on the details of the application.
>
>Regards
>
>Marc Brooker
>

First i m very new to this, i tried but i m not able to get any clear view
on this. I have to do it urgently, so i dont have time to research. My
application - I intention to increase the resolution of my data by 2ns,
which may b required to compensate 2ns jitter. Thats what i have been told
to do.  How can you suggest. Data rate is 80ms/s. 14 bit output from ADC.

amrish wrote:
>> amrish wrote:
>>> I hav a signal(time_domain). 80ms/s. Sample distance = 12.5ns. I wana
>>> interpolate by factor 6.
>>>
>>> Wht should i use, interpolation filter?
>>>
>> No offense intended, but you should consider doing your own homework. If
> 
>> you don't have a textbook, I like Oppenheim and Schafer, but others have
> 
>> other opinions.
>>
>> What is the application of this filter? What is more important: SNR, 
>> bandwidth or performance? How much data do you have? You need the 
>> answers to these questions before you find a solution to a real world 
>> problem.
>>
>> There are many types of interpolation filters which would be suitable. 
>> Which you choose depends on the details of the application.
>>
>> Regards
>>
>> Marc Brooker
>>
> 
> First i m very new to this, i tried but i m not able to get any clear view
> on this. I have to do it urgently, so i dont have time to research. My
> application - I intention to increase the resolution of my data by 2ns,
> which may b required to compensate 2ns jitter. Thats what i have been told
> to do.  How can you suggest. Data rate is 80ms/s. 14 bit output from ADC.
> 
> 

First, and most importantly, upsampling will not increase your 
resolution. You aren't going to get any more data than what you already 
have. If you know this already, then you can proceed.

Do you need to do this in real time? On a general purpose CPU or on a 
DSP? If not, then how much efficiency do you need? What kind of 
limitation can there be on your passband? What amount of distortion are 
you willing to put up with?

It's impossible to hand you a recipe for doing this without knowing a 
bit more about your system and application.

Cheers

Marc Brooker

hi marc,
though i am not sure of this, but interpolating this signal ie increasing
the resolution by 2ns might introduce noise?
APS
 




>amrish wrote:
>>> amrish wrote:
>>>> I hav a signal(time_domain). 80ms/s. Sample distance = 12.5ns. I
wana
>>>> interpolate by factor 6.
>>>>
>>>> Wht should i use, interpolation filter?
>>>>
>>> No offense intended, but you should consider doing your own homework.
If
>> 
>>> you don't have a textbook, I like Oppenheim and Schafer, but others
have
>> 
>>> other opinions.
>>>
>>> What is the application of this filter? What is more important: SNR, 
>>> bandwidth or performance? How much data do you have? You need the 
>>> answers to these questions before you find a solution to a real world

>>> problem.
>>>
>>> There are many types of interpolation filters which would be suitable.

>>> Which you choose depends on the details of the application.
>>>
>>> Regards
>>>
>>> Marc Brooker
>>>
>> 
>> First i m very new to this, i tried but i m not able to get any clear
view
>> on this. I have to do it urgently, so i dont have time to research. My
>> application - I intention to increase the resolution of my data by
2ns,
>> which may b required to compensate 2ns jitter. Thats what i have been
told
>> to do.  How can you suggest. Data rate is 80ms/s. 14 bit output from
ADC.
>> 
>> 
>
>First, and most importantly, upsampling will not increase your 
>resolution. You aren't going to get any more data than what you already 
>have. If you know this already, then you can proceed.
>
>Do you need to do this in real time? On a general purpose CPU or on a 
>DSP? If not, then how much efficiency do you need? What kind of 
>limitation can there be on your passband? What amount of distortion are 
>you willing to put up with?
>
>It's impossible to hand you a recipe for doing this without knowing a 
>bit more about your system and application.
>
>Cheers
>
>Marc Brooker
>

On Thu, 08 Feb 2007 14:10:24 +0200, Marc Brooker
<myrealname@gmail.com> wrote:

  (snipped)
>>>
>> 
>> First i m very new to this, i tried but i m not able to get any clear view
>> on this. I have to do it urgently, so i dont have time to research. My
>> application - I intention to increase the resolution of my data by 2ns,
>> which may b required to compensate 2ns jitter. Thats what i have been told
>> to do.  How can you suggest. Data rate is 80ms/s. 14 bit output from ADC.
>> 
>> 
>
>First, and most importantly, upsampling will not increase your 
>resolution. You aren't going to get any more data than what you already 
>have. If you know this already, then you can proceed.
>
>Do you need to do this in real time? On a general purpose CPU or on a 
>DSP? If not, then how much efficiency do you need? What kind of 
>limitation can there be on your passband? What amount of distortion are 
>you willing to put up with?
>
>It's impossible to hand you a recipe for doing this without knowing a 
>bit more about your system and application.
>
>Cheers
>
>Marc Brooker

Hi Marc,
  you're very considerate to try to help Amrish.
I always wonder about these posts that say,
"What's the solution to my problem?
Hurry and give me an answer because I don't 
have the time to learn the theory so that 
I can solve it on my own."

See Ya',
[-Rick-]
 

>
>Hi Friends,
>
>I hav a signal(time_domain). 80ms/s. Sample distance = 12.5ns. I wana
>interpolate by factor 6.
>
>Wht should i use, interpolation filter?
>
>Amrish.
>

Hi,

perhaps you could try with inserting 6 samples between every two adjacent
samples. The easy method is by using spline function. This works if you
are working in Matlab.