you may first try to figure out ur parameters in matlab/systemview/spw or sth. To design a filter is simple in concept, convolution, piles of multiply-add operations. You may also read some papers discussing different architectures of FIR implementations.
I've said the only things I need to know is about how to implement the complex flouting point multiplications with verilog in efficient way.
and after that I wanna use that in implementing FFT in my filter.
If u can plz help me in this way