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by chrismorgan 999 days ago
Starlink is low earth orbit, around 550km up, adding best-case latency of under 4ms (550km*2/c ≈ 3.67ms). That allows an excellent service.

Satellite phones (and I’ve confirmed this applies to the Huawei Mate 60) connect with satellites in geostationary orbits, meaning an altitude of about 35,786km, adding latency of around 240ms (35786km*2/c ≈ 238.74ms). This can be acceptable for some purposes, but harms things far more than you might imagine. (Source: personal experience with the Australian NBN SkyMesh or whatever it was called before NBN took it over, only once, about five years back. Look, a lot of the internet is located in the USA, and many things perform vastly worse from Australia than from the USA, e.g. several second page loads instead of under one second, and this satellite connection was basically that but even for stuff in Australia, and several times as bad for stuff in America.)

2 comments

There's a a Chinese plan for Guo Wang equivalent

https://rusi.org/explore-our-research/publications/commentar...

The mate 60 uses beidou sats which are not quite geostationary but also in a pretty high orbit.

But messaging is only a small part of their task, the main one is geolocation. They're only able to supply short message service where latency isn't really relevant.

I’m out of my depth here, but my research said Tiantong-1 and that that’s geostationary. Adding the keyword BeiDou I do get a few results too, but it looks like BeiDou is GNSS, so I think those might be errors?

Anyway, my point was just that this stuff isn’t equivalent to Starlink. For what satellite phones do, GEO or whatever similar is fine, but the appeal of Starlink certainly requires that it be LEO.

I didn't look into it but I read that in a review, that BeiDou-3 sats have a sidechannel for emergency comms and that this is what's being used. Perhaps that info was wrong, it's hard to get info on this in Europe.

If this is the case it would be too bad though, because Tiantong-1 is indeed geostationary (leading to suitability issues for emergency comms like needing visibility to the Southern horizon) but also only available in the China region.