New Zealand is about to test long-range wireless power transmission

Re:New Zealand is about to test long-range wireless power tr... by superkuh on Thursday September 10, 2020 @12:33PM (#24433874)

Path loss through free space at these relatively low frequencies (<6 GHz) isn't from air/water vapor losses. It's from diffraction spread.

This company can say all they want about near field tech, but the beam waist diameter relative to wavelength determines the diffraction spread. And that aspect of path loss is proportional to the distance in wavelengths even if there's no "absorption" by the air components. For any reasonable link at 2.4-5.8 GHz the length in wavelengths will be tens of thousands.

[ Parent | on HN ]

Re:New Zealand is about to test long-range wireless power tr... by Emrod on Thursday September 10, 2020 @05:14PM (#24436632)

The equations governing diffraction are relatively straight forward. We are operating within the near-field (or more accurately in the Frensel range). I'm sure you can do the math and see how focusing a phased array can reduce diffraction at this range :)

[ Parent | on HN ]

Re:New Zealand is about to test long-range wireless power tr... by superkuh on Thursday September 10, 2020 @09:35PM (#24438324)

Just make sure to do your liability math because in a about a year you're going to have a lot of investors very angry at you.

[ Parent | on HN ]