Compensate for FIR filter attenuation

1. How do you compensate for filter delay?
2. How do you normalize FIR filter coefficients?
3. What are the conditions to be satisfied for linear phase FIR filters?
4. What is the condition for the impulse response of FIR filter to satisfy for a constant group and phase delay only for constant group delay?
5. Which filter Realisation is used for FIR filter?

How do you compensate for filter delay?

When the shift is constant, you can correct for the delay by shifting the signal in time. Sometimes the filter delays some frequency components more than others. This phenomenon is called phase distortion. To compensate for this effect, you can perform zero-phase filtering using the filtfilt function.

How do you normalize FIR filter coefficients?

The coefficients are then normalized by dividing by the sum of the coefficients themselves. This is done in order to have a DC gain equal to 1 (0 dB). At this point the FIR filter is a low pass filter. By negating every other coefficient, the FIR filter becomes a high pass filter.

What are the conditions to be satisfied for linear phase FIR filters?

A FIR filter is linear-phase if (and only if) its coefficients are symmetrical around the center coefficient, that is, the first coefficient is the same as the last; the second is the same as the next-to-last, etc.

What is the condition for the impulse response of FIR filter to satisfy for a constant group and phase delay only for constant group delay?

The group delay is constant for all frequencies, because the filter has a linear phase, i.e. its impulse response is symmetrical (or asymmetric).

Which filter Realisation is used for FIR filter?

FIR filters that are embedded in adaptive FIR filters are often realized by a lattice structure [13,14,15]. A drawback is that there are two multiplications and two additions for each filter coefficient, but two complementary filters are computed simultaneously.