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Altera_Forum
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15 years ago

Unwanted offset attenuation in FIR filters

My FIR is now working so far - thanks to Altera Guru "MSchmitt" - but I still have two problems left. Please have a look at the attached pictures - there is an unwanted offset attenuation of 6dB in t...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
15 years ago

I've added a measurement without a FIR filter in between ADC and DAC - so it seems that 3dB are lost (maybe) in the coneverters - but the remaining 3dB must have to do something with the FIR filter.

Loosing exactly half of the signal could indicate a problem with the sign!? - or the converters do not work correctly.

What should I try next?