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.

  • HiTekRedNek@lemmy.world
    link
    fedilink
    English
    arrow-up
    4
    ·
    12 hours ago

    Except that theory has no basis in reality.

    Microwave ovens work by concentrating that energy into a very small space.

    When is the last time you were cooked by radio waves?

    Microwaves ARE radio waves.

    • cynar@lemmy.world
      link
      fedilink
      English
      arrow-up
      6
      ·
      10 hours ago

      Assuming 1MW of transfer, and a 10m diameter beam, your looking at 12.5kW/m^2 . Not instant vaporisation, but dangerous in seconds to humans. The penetration was also mean the energy is delivered internally, where it’s harder to deal with (short term).

      Any viable power transfer beam also, inherently, makes a good anti personnel weapon.

      While the maths is slightly better for short range transfers, like drones, it would still definitely not be something you want hitting your body.

    • sp3ctr4l@lemmy.dbzer0.com
      link
      fedilink
      English
      arrow-up
      4
      ·
      10 hours ago

      Are you somehow entirely unaware of the DEW crowd control devices that have been being used for like 2 decades now?

      https://en.wikipedia.org/wiki/Active_Denial_System

      Yeah, the whole point of these things is they basically microwave the outer layer of your skin, when in wide beam mode.

      Or, they can be dialed in to be a more concentrated beam… to uh, internally heat up a bit more than just your skin.

      But uh, for legal reasons of course nooo they do not do that and cannot do that.

      While it is claimed not to cause burns under “ordinary use”,[50][51] it is also described as being similar to that of an incandescent light bulb being pressed against the skin,[14] which can cause severe burns in just a few seconds. The beam can be focused up to 700 meters away, and is said to penetrate thick clothing although not walls.[52] At 95 GHz, the frequency is much higher than the 2.45 GHz of a microwave oven. This frequency was chosen because it penetrates less than 1⁄64 of an inch (0.40 mm),[53] which – in most humans, except for eyelids and the thinner skin of babies – avoids the second skin layer (the dermis) where critical structures are found such as nerve endings and blood vessels.

      I would imagine that if you had an emorous amount of microwave energy from an orbiting solar array, being beamed to a recieving station on earth, (ie, a very small small space compared to the distance involved) and it uh, missed, yeah, yeah it would microwave people.

      There’s also this:

      https://pmc.ncbi.nlm.nih.gov/articles/PMC8733248/

      Brief but intense pulses of radiofrequency (RF) energy can elicit auditory sensations when absorbed in the head of an individual, an effect known as the microwave auditory or “Frey effect” after the first investigator to examine the phenomenon (1). The effect is known to arise from thermoacoustically (TA)-induced acoustic waves in the head (2).

      Lin has proposed that the Frey effect may be linked to unexplained health problems reported by U.S. officers in Cuba and elsewhere, the so-called Havana syndrome (3).

      Probably don’t tell any schizophrenics you may or may not know about that.

    • LincolnsDogFido@lemmy.zip
      link
      fedilink
      English
      arrow-up
      3
      ·
      11 hours ago

      Yeah, xrays are also radio waves. That doesn’t make them inherently less dangerous. Plenty of people have made mistakes around ground and ship based radar systems too and have accidentally cooked their insides. Just because 5G conspiracy theorists took over that argument doesn’t mean it has no basis in reality.

        • LincolnsDogFido@lemmy.zip
          link
          fedilink
          English
          arrow-up
          2
          ·
          10 hours ago

          https://academic.oup.com/milmed/advance-article/doi/10.1093/milmed/usaf613/8404557

          It doesn’t mention specific cases, but there’s a local man who described his time working on radar arrays during his time in the Navy before he was medically discharged. His explanation of events was that he turned off the array while he was performing maintenance on a specific radar antenna, but someone turned it back on when he was still working. He said he heard the array come back online and stopped working, but there was thermal damage done to his testes.

          I have no reason to doubt him because clearly its possible. But the primary point stands. There’s enough evidence within the military to warrant safety guidelines when working with radar emitters.