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The receiving rectenna would be large, but from what I know it would basically consist of a spaced array of small vertical antennas. The sat does not need to b

by evgen 5y ago

The receiving rectenna would be large, but from what I know it would basically consist of a spaced array of small vertical antennas. The sat does not need to be in geostationary orbit and in fact a better solution is to have a constellation at lower orbits. This also eliminates the last problem you posed because if something goes wrong with the sat you just de-orbit it before you had planned and write it off. If you fly through the beam or walk through it you would not know. Do you feel a slight warming when you put your hand on top of your wifi antenna? There are problems with space-based solar and beaming energy, but none of your objections make the list.

xt00 5y ago
The non-geostationary design in low-earth orbit is mentioned with not much detail in this article and would generate far less power for a particular receiving location since it only periodically receives power -- so there are various objections to that approach as well. In the case of the geostationary energy being sent through the atmosphere to the receiver -- they mentioned 2000MW of power being delivered -- assuming you use the area of a house (as viewed from top down) as an area to compare against, by some rough calculations roughly 10KW would be impinging upon a house surface that is roughly 1500sqmeters -- so 10KW of microwave energy directed into a house area -- that is non-trivial, so I assume your comparison between wifi antenna's was in reference to the low earth orbit solution -- the geo stationary solution referenced in the article is very powerful and would be in a totally different class from the approx sub 1W range coming from your wifi antennas. So I would be worried to walk through it.
senectus1 5y ago
>in fact a better solution is to have a constellation at lower orbits only that this turns the cost of something that is already very very expensive into something that is hideously ridiculously expensive.
- evgen 5y ago
  No it doesn’t. The major cost is not the satellite structure, it is getting up there. Low orbit costs significantly less.

by evgen 5y ago

xt00 5y ago

The non-geostationary design in low-earth orbit is mentioned with not much detail in this article and would generate far less power for a particular receiving location since it only periodically receives power -- so there are various objections to that approach as well. In the case of the geostationary energy being sent through the atmosphere to the receiver -- they mentioned 2000MW of power being delivered -- assuming you use the area of a house (as viewed from top down) as an area to compare against, by some rough calculations roughly 10KW would be impinging upon a house surface that is roughly 1500sqmeters -- so 10KW of microwave energy directed into a house area -- that is non-trivial, so I assume your comparison between wifi antenna's was in reference to the low earth orbit solution -- the geo stationary solution referenced in the article is very powerful and would be in a totally different class from the approx sub 1W range coming from your wifi antennas. So I would be worried to walk through it.

senectus1 5y ago

>in fact a better solution is to have a constellation at lower orbits only that this turns the cost of something that is already very very expensive into something that is hideously ridiculously expensive.

evgen 5y ago
No it doesn’t. The major cost is not the satellite structure, it is getting up there. Low orbit costs significantly less.