It is possible to create a digitally controlled analog circuit
by replacing resistors with DACS.

The DACS may talk to ladders of resistors

or one may use digital potentiometers, I'm not sure.

But the principle is the key.

See slide and substitute appropriate parts with acceptable bandwith.

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A simplifying approach for your wideband radio is emerging.

Keep as much of the radio in software as possible.

use a digitally controlled active gain filter for both noise reduction and tuning.

Use a transverter to grab chunks of bandwidth that are out of range of the software demodulation.