Is it possible to transmit half-wave signals repetitively, like repetitive "north" magnetic fields like going from 0-1 Gauss "north" and repeat however many times per second without going 0-north-0-south like a full-wave signal?
Look at Maxwell's equations: There are nabla operators in them - these will only pick up changes in the value over time.
That means the receiver will ignore any DC offset regardless whether it is magnetic or electric (unless it is very very close to the sender).
Also note that rectifying a (HF?) signal will change it in the frequency domain quite a bit - which does affect the receiver.