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Comment by wcoenen | Hacker News Reader

Teslarati is reporting that these satellites will not yet have the laser interlinks. I guess that means they can't route traffic from satellite to satellite; they can only bounce data traffic back down to a base station.

https://www.teslarati.com/spacex-starlink-satellites-tease-r...

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I saw an unsourced comment on reddit that claimed they would have a microwave interlink instead of the laser interlinks, which would give several orders of magnitude lower bandwidth (although still better than nothing).

Either way, I think that these are mostly being put up to serve two important purposes: testing various technologies with enough test vehicles to get strong(ish) statistics, and working their way to the thousands of deployed satellites the FCC will require them to have deployed if they don’t want to lose their frequency allocation.

I have also heard that they are having some trouble with the laser interlinks and alignment as well as the cost of them at this point, so they are starting with the microwave interlinks. They still plan on doing the laser interlinks eventually, but they weren't reliable or cheap enough by the time they wanted to begin launching, so they are being left off this first batch.

All of that is completely unsourced and heard through anonymous sources that have posted on various forums, so take it with as much salt as you need.

Oh, microwave links effectively nothing compared to the laser ones. Terrible news. So I guess marketed bandwidth will never be delivered within the first generation of the network.

>they weren't reliable or cheap enough

Sounds highly plausible to me, given [1]. I won't say that they won't eventually get there, but it's definitely not going to be a cakewalk.

[1] https://news.ycombinator.com/item?id=19892265

To use microwave inter-satellite links, SpaceX would have needed to file for frequency allocations. As far as I know, they have not done so - they only have frequency allocations requested (and approved) by the FCC for the up and downlinks. I think this largely rules out microwave ISLs on this batch of satellites.

What laser interlinks are the planning to use anyway? Do they plan on making their own, or to buy them?

I've helped with EDRS [1] and I can confidently assert that these things are everything but trivial to get to work well. The technology is so highly sophisticated on so many levels that I was quite literally shocked more than once during that time.

[1] https://en.wikipedia.org/wiki/European_Data_Relay_System

I don't know about making their own lasers, but they are almost certainly making their own laser interlink system.

If there’s one thing that SpaceX/Tesla seem to universally excel at it is their electronics / board / chip design.

Listening to Sandy Munro rant about so many things he doesn’t like about how Tesla builds their cars, one thing he is awed by is their electronics.

I will say that they fucked up the eMMC chip in their first gen MCU though, people are out there unsoldering, cloning, and replacing the chip to try to bring back their cars from the dead to avoid paying ~$3k for a whole new MCU.

[1] - http://teslaservicemanual.com/2019/01/18/replacing-emmc-in-m...

Electronics alone is only one of many thing's they'll have to excel at to produce reliable laser terminals.

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