Scientists in China have demonstrated a wireless power transmission system that uses a ground-based microwave emitter to beam energy to an antenna array mounted on the aircraft’s underside. Importantly, they were able to do this while both the drone and charging system were in motion.
In tests, the car-mounted system kept fixed-wing drones in the air for up to 3.1 hours at an altitude of 15 metres (49 feet). The key challenge that the team overcame was maintaining alignment between the emitter and the drone during flight, wrote Song Liwei, the project’s leader.
Yes but you are charging through a conductive cable. It’s not even remotely the same as charging something with microwaves.
The power delivered decreases exponentially with distance. I’m sure you’ve heard the phrase “inverse square law”.
Because you divide the effect and gain by 4pi(r^2) meaning your output is decreased by 75% every time you double the distance.
You’re going to need ridiculously powerful hardware and an enormous amount of electricity to run it on any meaningful distance.
A concentrated, collimated beam doesn’t act like a point source. There’s of course some amount of scattering and absorption loss due to atmospheric particles, but other than that a fully collimated wireless energy transmission doesn’t lose intensity over distance. Kind of obvious, really, because “where would the energy go?”.