Correct. If you look at the block diagram of the AD9084 (from the article link), it has on-chip DUC (Digital Up Converter) and DDC (Digital Down Converter) blocks.
That's not really true, there's plenty of applications that use these sort of bandwidths. A big one is optical communications (28 GHz bandwidth is actually not super high there), but also some specialised microwave comms and radar/military. They alm do processing at 10s to 100s of GS/s (obviously highly parallel).
While full bandwidth applications certainly exist, it is rare. Most direct sampling schemes are used for having a purely digital RF front end within the Nyquist range of the ADC/DACs. It's cheaper and easier to develop firmware/gateware than debug analog RF issues and respin hardware.
drmpeg|2 years ago
https://www.analog.com/en/products/ad9084.html
cycomanic|2 years ago
oscillonoscope|2 years ago
KeplerBoy|2 years ago
Get your data into the system via PCI-E, do some RDMA magic to get the data onto your GPU and put the cores to work.