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How to choose the right MIPS for my filters design

Started by domistep February 12, 2004
HEllo,

I have an acquisition system of 30 measurements.
The sampling rate for one acquisition is 1000 Hz.
Each acquisition must be filtered with a FIR with 16 Taps and 16
sample of the signal acquistion will be used.

I will use a TSM320C2xxx with a frequency of 150 Mhz.

How many MIPs do i need to achieve thoses filtering operations.

Thank oyu
"domistep" <domistep@free.fr> wrote in message
news:11efef01.0402121320.2b852753@posting.google.com...
> HEllo, > > I have an acquisition system of 30 measurements. > The sampling rate for one acquisition is 1000 Hz. > Each acquisition must be filtered with a FIR with 16 Taps and 16 > sample of the signal acquistion will be used. > > I will use a TSM320C2xxx with a frequency of 150 Mhz. > > How many MIPs do i need to achieve thoses filtering operations. > > Thank oyu
Around 1 MIP - Your processing task is rather simple for modern DSPs from a filtering point of view. Make sure you pick a way of multiplexing all of your sample data (from 30 different sources?) together for efficient handling. Do you need to do all 30 measurements at the same time? You may not need a DSP at all - depending on the latency/concurrency requirements you may just need an aquisition board attached to a PC and let the PC do the processing. -- Clay S. Turner, V.P. Wireless Systems Engineering, Inc. Satellite Beach, Florida 32937 (321) 777-7889 www.wse.biz csturner@wse.biz
"Clay S. Turner" <CSTurner@WSE.Biz> wrote in message news:<8vVWb.21353$A75.11627@bignews5.bellsouth.net>...
> "domistep" <domistep@free.fr> wrote in message > news:11efef01.0402121320.2b852753@posting.google.com... > > HEllo, > > > > I have an acquisition system of 30 measurements. > > The sampling rate for one acquisition is 1000 Hz. > > Each acquisition must be filtered with a FIR with 16 Taps and 16 > > sample of the signal acquistion will be used. > > > > I will use a TSM320C2xxx with a frequency of 150 Mhz. > > > > How many MIPs do i need to achieve thoses filtering operations. > > > > Thank oyu > > > Around 1 MIP - Your processing task is rather simple for modern DSPs from a > filtering point of view. Make sure you pick a way of multiplexing all of > your sample data (from 30 different sources?) together for efficient > handling. Do you need to do all 30 measurements at the same time? You may > not need a DSP at all - depending on the latency/concurrency requirements > you may just need an aquisition board attached to a PC and let the PC do the > processing.
Thank you for your amswer.. The point is that i have to choose the way those acquisition will have to be performed. Using a TMS320F28xx, the 30 inputs will be multiplexed and will be use on GPIO. If multiplexing is done , i surely can t do the 30 acquisitions in the same time. I ll have to think about the way to do it
Hello Domistep,
Even with staggered sampling, you can make the measurements effectively at
the same time. Basically design an FIR lowpass filter and subdivide the
impulse response into 30 different filters[1]. Now each filter has an
incrementally different delay, so run each of the 30 inputs through their
respective delay compensating filters and you will have all of your data
time aligned. And since you are looking at a fast DSP, the MIPS issue isn't
really an issue at all. This is an application of a polyphase filter.

IHTH,
Clay

[1] There are other ways of generating the polyphase filter, windowed sinc
etc., but this way is quick and simple to do with a Parks-McClellan Algo and
it is easy to bound the resampling error.

-- 
Clay S. Turner, V.P.
Wireless Systems Engineering, Inc.
Satellite Beach, Florida 32937
(321) 777-7889
www.wse.biz
csturner@wse.biz



"domistep" <domistep@free.fr> wrote in message
news:11efef01.0402130605.4ba12a0a@posting.google.com...
> "Clay S. Turner" <CSTurner@WSE.Biz> wrote in message
news:<8vVWb.21353$A75.11627@bignews5.bellsouth.net>...
> > "domistep" <domistep@free.fr> wrote in message > > news:11efef01.0402121320.2b852753@posting.google.com... > > > HEllo, > > > > > > I have an acquisition system of 30 measurements. > > > The sampling rate for one acquisition is 1000 Hz. > > > Each acquisition must be filtered with a FIR with 16 Taps and 16 > > > sample of the signal acquistion will be used. > > > > > > I will use a TSM320C2xxx with a frequency of 150 Mhz. > > > > > > How many MIPs do i need to achieve thoses filtering operations. > > > > > > Thank oyu > > > > > > Around 1 MIP - Your processing task is rather simple for modern DSPs
from a
> > filtering point of view. Make sure you pick a way of multiplexing all of > > your sample data (from 30 different sources?) together for efficient > > handling. Do you need to do all 30 measurements at the same time? You
may
> > not need a DSP at all - depending on the latency/concurrency
requirements
> > you may just need an aquisition board attached to a PC and let the PC do
the
> > processing. > > Thank you for your amswer.. > > The point is that i have to choose the way those acquisition will have > to be performed. > Using a TMS320F28xx, the 30 inputs will be multiplexed and will be use > on GPIO. > If multiplexing is done , i surely can t do the 30 acquisitions in the > same time. > I ll have to think about the way to do it