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) ?

Kaushal

The approach will work without any performance degradation. It will however add

delay. There is also no harm in putting all zeroes at the trailing edge.

Kaushal