[Elecraft] RF Noise canceller ?

[Marinos Markomanolakis, M.D.]

Just a question for the technically inclined group members:

How feasible or worth the effort, would be the addition of an option to the 
K2 which would sample RF noise from a ferquency close to the used 
band,(tunable?) which is devoid of signals, phase invert and reinject the 
noise to an IF stage or even the antenna input in order to cancel our the 
"white or pulse" noise components, preserving the desired signal ?

Why similar circuits are not preferred in HF receiver designs instead of DSP 
filters ?

Similar circuits are commonly used in biomedical devices (called linear 
averagers if I am not mistaken) and are very effective in isolating electric 
signals from a particular organ eg Heart in EKG or brain area of interest in 
EEG, filtering out the irrelevant noise from the muscle cells...

Just some food for thought.