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Comment by joecool1029 | Hacker News Reader

So long as you don't live in a crater or have skyscrapers blocking your view line of sight should not be an issue for a majority of the population. Starlink wouldn't require a specific southern view of the sky like a GEO system does but it won't do well in 'urban canyons'. MEO consumer things you might be familiar with that experience reduced signal in the described conditions include GNSS (GPS) and SiriusXM.

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Starlink is not meant for densly populated areas where 'urban canyons' as you called them would be found. The bandwidth of the simultaneously reachable satellites is basically constant everywhere, except at higher latitudes where satellites on different orbital planes get closer to each. So distributed users are preferred to lots of users in a single place, since the latter would have to share the bandwidth while the same number of distributed users would access via different satellites instead and would see an increased total bandwidth available.

Look at the graph on "population and satellite density per degree" in [0] to see why SpaceX has most likely chosen the inclination that they use.

[0] https://caseyhandmer.wordpress.com/2019/11/02/starlink-is-a-...

Sirius is now GEO, but has ground repeaters in problem areas.

GPS has the advantage of seeing multiple satellites and working with that by design since its one way. Despite that, Japan launched its own satellite to supplement GPS because it had so many issues. I think we’re spoiled by our phones that supplement GPS with cellular signals, wifi and inertial references.

The newest phones actually even do dual-frequency GPS using a newer signal (L5). It's accurate enough to do lane-keeping.

Existing systems also supplement GPS network data with russia's GLONASS, as well as sometimes WAAS if the satellite gets picked up (WAAS is GEO system to provide for additional accuracy, since it's further and requires a path facing south, it's not often picked up on phones)

>Inertial reference

Can we really do inertial reference with current phone hardware? I would imagine our usecases don't really even give inertial reference a nice playing field.

>Can we really do inertial reference with current phone hardware?

Yes, check the specs for any recent (past 3 years) qualcomm chipset, initia sensors will be included. You can play around with this sensor (and others) using the Phyphox app for ios and android.

Maybe my terminology isn’t ideal, but I figured my NAV apps can tell I’m doing things like a U-Turn based on G-forces. But maybe it’s just using its compass.

My old Garmin wouldn’t realize I did a u-turn until I have half way back down the street.

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