Hi 

We have two FIR Filters, running on same input data, generated for different purposes.
1. FIR1 - N Taps (as generated in Matlab)
2. FIR2 - N+10 Taps (as generated in Matlab)

Case 1
======
Have 2 separate Input Data Arrays of length matching to the taps.
i.e. 
Array 1 of length N for FIR1.
Array 2 of length N+10 for FIR2.
Feed the incoming input sample to both the arrays.

Case 2
======
Have a single Input Data Array of length N+10.
i.e.
Array of length N+10 for both FIR1 & FIR2.
Feed the incoming input sample to the array.
Add 5 zeroes on each side of the filter coefficients for FIR1 to make it length / taps as N+10.

i.e. 
FIR1 = [0, 0, 0, 0, 0, N Original Generated Coefficients, 0, 0, 0, 0, 0]
FIR2 = [N+10 Original Generated Coefficients]

"Case 1" brings in complexity in our design and hence we were looking into "Case
2" and have certain queries:
1. Will adding zeroes degrade the performance of the filter i.e. roll-off/ attenuation etc. ?
2. Will the group delay of the Filter(original generated with added zeroes) differ from the
Filter(original generated coefficients) ?

Regards
Chinmoy.

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