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Laser Light Communications (US) plan for several dozen optical high speed data links between satellites and ground is described in Aviation Week's article Big Gains On Horizon For Laser Communications Suppliers and Lightwave's online website: Laser Light to leverage free-space optics in space for Optical Satellite as a Service.

All Optical Hybrid Global Network (or HALO, as laser Light calls it)

The plan is to use lasers to establish optical links between satellites in Earth orbit (MEO) and between them and a network of ground stations.

According to the company's website, Laser Light will leverage 8 to 12 satellites in medium Earth orbit to create a network that will offer an initial service capacity of 7.2 Tbps. The satellites will pass signals among themselves and to the ground via free-space optics. The space interconnections will include 48 links of 200 Gbps apiece, as well as 72 steerable up/down links to Earth at 100 Gbps. (my emphasis)

edit: Confirming that the plan is to establish several dozen laser communications link between ground stations and satellites, from the article The Speed of Light: Laser Light and Optus Explain Optical Communications Partnership:

Laser Light’s hybrid network is broken into two elements: an OSS part and the Ground Network System (GNS). The OSS half is comprised of a constellation of eight to 12 Medium Earth Orbit (MEO) satellites, which beam down data to a GNS via a completely optical spectrum. The data then connects to terrestrial fiber infrastructure, such as the one Optus already has in place. (my emphasis)

enter image description here

above: Graphic from The Speed of Light: Laser Light and Optus Explain Optical Communications Partnership to Via Satellite Magazine Note: since the satellites are in medium Earth orbit (MEO) and not Geosynchronous orbit (GEO), these beams would not be fixed, but in fact scan repeatedly through tens of kilometers of airspace each.

These would not be narrow, millimeter-diameter beams like we see from laser pointers. In order to combat diffraction, they would actually be expanded to at least tens of centimeters in diameter or larger. There is also a chance they would be just outside the visible wavelength range in the (very near) infrared. So I would guess there is a good chance that - depending on the actual implementation - these beams might not actually pose any risk to a pilot if an aircraft passes though one, but I don't know that for a fact.

I would like to know who must approve globally distributed continuous laser data links between Earth stations and orbiting Satellites in the context of aviation safety.

The answers to the related question How does aviation deal with satellite and Moon laser ranging, and other scientific lasers in the sky? seem to suggest that there are some rules and best practices associated with ground-based lasers from observatories that are used intermittently, but in the case of bidirectional, near continuous laser traffic from dozens to perhaps hundreds of sites (each satellite has 72 independently steerable beams) the existing procedures (having two human spotters watching for planes) would not really be feasible.

There is some discussion here but I don't see any mention of aviation.

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    $\begingroup$ @mins Thanks. This is a bit different - maybe a 100 or more laser beams moving around day and night, 24/7 and probably not all in low air traffic locations where they can just shut off the internet if a spotter notices a plane in the area. $\endgroup$ – uhoh Oct 13 '16 at 9:41
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    $\begingroup$ Yes of course. The problem here is that neither power or frequency is known. IR would be a problem for eyes for instance, but power may not be a problem at all, a minimum slant distance could be imposed, and 10 Gb/s may not need high powers (it's a matter of signal/noise ratio). On the ground radio-amateurs use IR leds (not lasers) for 10/30 km data links. $\endgroup$ – mins Oct 13 '16 at 9:56
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    $\begingroup$ just because the beams are wider doesn't mean they're not problematic. The power required would be quite a bit higher than your laser pointer to get a decent signal at hundreds to thousands of kilometers of range, especially given the beam width being of necessity large. And to burn through atmospheric blooming your power requirements get to be even higher. Think of dozens or hundreds of ABM lasers being up 24/7. Would need to be a permanent no-fly zone of quite a size around each of them. $\endgroup$ – jwenting Oct 13 '16 at 11:19
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    $\begingroup$ @jwenting yep I understand. I didn't wanted to raise a "sharks with lasers" alert. Visible sunlight is a few hundred watts per square meters. I'm asking here because I'd like to see if this has been addressed quantitatively somewhere, but I'm guessing these beams would also be of the same intensity. They have to be wide so that they won't diverge due to diffraction. For a given received signal strength, a beam starting with twice the diameter will go 2 times farther, but twice the power only gets you 1.4 times. $\endgroup$ – uhoh Oct 13 '16 at 11:48
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    $\begingroup$ @abelenky thanks, but this is definitely about lasers between satellites and ground stations passing through aviation airspace. Thus the map showing eight satellites and dozens of ground stations and green lines connecting them, and the quote in bold: "The satellites will pass signals among themselves and to the ground via free-space optics" $\endgroup$ – uhoh Oct 15 '16 at 4:14

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