My IF is 5Mhz.
I need to reduce my sampling frequency 409.8Mhz to 20.48 Mhz by using FIR lowpass filter, so i am decimating it in 2 stages , first time i am using cic filter and decimation factor 5 then i will get the new sampling frequency 81.9 which is given to half band filter by decimating factor 4 then we will obtain finally 20.48 Mhz.

i also would like to know which filter will be best suitable for this for decimation... if i am wrong in selecting the filers ..

parameters ; passband is 0.1dB, stop band is 30dB, passband frequency 10Mhz, Stop band 15Mhz.

i need matlab code for this and if possible vhdl code 2...

it will be great help for me ....

waiting for reply,

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