Hi ,
The chip suport 12GHz at RF signal but sampling is only 3Gsps.
How to get the great sampling at 4th Nyquest??
Example:
Input Signal= 11.8GHz~12GHz , What 's output EVM value at digital domain??
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Hi ,
The chip suport 12GHz at RF signal but sampling is only 3Gsps.
How to get the great sampling at 4th Nyquest??
Example:
Input Signal= 11.8GHz~12GHz , What 's output EVM value at digital domain??
Hi,
The RF sampling is based 'band-limited' sampling of the input signal. So that if the input signal (11.8G - 12G = 200M BW), then ADC sampling at ~3GHz will not result in aliasing within the 200MHz channel BW. I will draw this out in a plot to demonstrate.
regards,
Ali
Hi Syed,
I find out a good tool in TI; https://www.ti.com/tool/FREQ-DDC-FILTER-CALC
I set Fs=3000MHz, Interleave=1, Fc=11900MHz, BW=200MHz.
I get: Rx band=50~150MHz, HD2=100~300MHz, HD3=150~450MHz,
The HD2 have interfere the Rx band,
I guess the Rx EVM is not good Does it correct??
Gordon,
If possible, please move Fc around such that HD2 and HD3 does not land in-band as the RX band. You may also want to consider using our HD2 correction/calibration, available on the AFE7952 to correct the HD2 to lower level to not impact the in band signal. Thank you.
-Kang