analog to digital problem

[h_rafii]

hi;

i have 10 mhz bandwidth in 200-210 mhz and i want to convert it to digital with 20msps and 10 bit resolution.

any way i wanna know shall i down convert the signal to 0-10 mhz or can i down convert it to 50-60 mhz and sample it with 20msps adc??
( there is some problem with adc (dc problem and mixer problem)if i wanna take the data down to 0-10 mh!!!)

 

[kookooli]

Your sampling frequency should be double the maximum frequency in your waveform(Nyquist)
if your maximum frequency of your signal is 10MHz your sampling speed should be at least 20MSPS and if your maximum frequency is 200MHz your sampling speed should be at least 400MSPS .