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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...
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Altera_Forum
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15 years ago

@kaz:

Multiplying the FIR filter output with 2 lead to a output signal stuck at GND. I've tried to use the multiply operation before and after the FIR filter.

@FvM:

The output signal seems to have no DC component - an average measurement with an Agillent DSO7012A delivered -100µV, while measuruing an aplitude of 206mV.

This is strange, because in the Signal Tap II Logic Analyzer, the output signal occupies only one half of the diagrams scaling.

From tomorrow on, I will be on vacation until next week - so don't wonder if my replies do not come in time.