DC offset removal using FPGA?

I understand the method provided by Kaz, i think. But i lag the connection of how do we implement this DC filter using FPGAs, as this would would be my first attempt to try some DSP usinf FPGAs.

I have data from a transducer and it is being passed through ADc and then deserialized.

I will check for the DC and AC coupling.

But if i am right, i need to simulate this model using matlab to atleast figure out the basics of how moving average filter works.

Thankx

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I am new to interface FPGAs with DSP concepts. I have ADCs and then i have deserializers after them to parallelize the data. So should i apply the DC removal after the deserializer or before it?

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Can you control the DC offset in the analog domain? If so, it would be better to eliminate it there, as then you can use the full dynamic range of your ADC.

Where is this DC coming from? If your ADC is AC-coupled, then the DC could be due to a bad input offset voltage, which some ADCs provide controls to eliminate. If your ADC is DC coupled, then you need to decide why its DC coupled, and decide if you want to change to AC coupling for your current application.

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Also, i need guidence regarding the DC removal.I have studied about it but got nothing as a final conclusion that whether to apply a HPF or LPF and then a subtractor.

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What is the signal you are trying to measure?

If you are digitally demodulating your signal and then filtering it, its quite possible your digital filter will be sufficient to remove the DC. Whether this would be sufficient, depends on how much DC is getting into your system, i.e., if you have a huge DC spike, then your filter stop-band rejection might need to be very high to remove it.

You can also use the methods Kaz suggests in the thread he references, or a combination of DC removal filter, followed by digital demodulation and further filtering.

Cheers,

Dave

See my post at:

http://www.alteraforum.com/forum/showthread.php?t=29991&highlight=dc+filtering&page=2

you filter your data when parallelised into readable samples.