Hi,

I tried to create a FIR filter with the wizard using the following setup but noticed the FIR coefficients were twice the value they should be which in turn was giving twice as much gain as expected. Have I configured something wrong or is there a bug?

Hi Rob,

Corresponding to the AD9361 design, the filter design wizard calculates the gain in a different way than yours.

If you look into the filter design function: ad936x-filter-wizard/internal_design_filter.m at 2016_R1 · analogdevicesinc/ad936x-filter-wizard · GitHub

From Line 549 to Line 576, you will find how the gain is determined. Then, Line 578 and Line 579 calculates the coefficients based on the gain.

- Di