Even if viasat's consumer service was handing out high quality steel 1.8 meter elliptical offset ku band dishes with norsat PLL LNBs and 8W BUCs to consumers, the path loss and modulations required would mean that a given section of contended (let's say, 10MHz of a transponder) service to many terminals would still have significantly lower speeds and greater oversubscription to be economically viable compared to what end users see right now on starlink.

that's simply not true. they have transponders that should deliver 10Gbps to a single user IF they were willing to pay for both the service and terminal. SpaceX is limited in the exact same way, and their terminals + satellite costs are much higher for the number of them.

10Gbps to a single terminal using exactly what modulation and code rate, and channel size?

Or course you can achieve high speeds over geostationary if you throw entire transponders full of MHz at the problem. Which has a proportionally huge monthly recurring cost to control that transponder space. Or as a total percentage of the satellite's transponders dedicated to your network.

Yes satellite tx power from the twta is more powerful than it used to be. You still need a huge ass earth station to start doing 16apsk/32apsk reliably.

I'm not sure what point you're trying to make here. starlink is also multiple smaller beams within a single beam for frequency reuse. a single beam does not get more bandwidth (in Gbps) than a viasat terminal.

> You still need a huge ass earth station to start doing 16apsk/32apsk reliably.

16apsk has been used for about a decade now on GEO satellites. I'm not sure why the gateway size matters when we're talking about user speeds.

If you don't understand why in a geostationary based link, the antenna size at either end matters a great deal for overall link budget, gain, Eb/No and what modulation you can use at a certain MCS and code rate before it gets too blurry in a QAM eyeball chart, there's no sense in talking about satellite communications with you.

I note you didn't answer my question because you have no idea of what modulations, channel size and such are required to actually push 10Gbps through a satellite link to a single terminal. I think you're going off Viasat's marketing material where they're claiming aggregate throughput of an entire satellite or something.

Show me the exact hardware configuration of modems you think are capable of 10Gbps by geostationary and how much transponder MHz it needs.

I literally just said that 16APSK has been used for a decade on Geo satellites. I don't know if you aren't aware what modulation means, but that is the modulation. it does not matter at all what size the gateway or the user antenna is. 16APSK (actually 32APSK is used as well) and the carrier size tells you all you need to know about the speeds, unless you've never done a link budget or worked in this industry.

I said if they wanted to they could sell a 10Gbps plan, because that's what the link budget allows. they don't, of course, because it's not profitable. SpaceX also could in theory, do that, but they also don't. your original claim is that SpaceX somehow has far greater bandwidth to an area than Geo is patently false.

> the path loss and modulations required would mean that a given section of contended (let's say, 10MHz of a transponder) service to many terminals would still have significantly lower speeds and greater oversubscription to be economically viable compared to what end users see right now on starlink.

if your definition of economically viable is getting VC money and government subsidies pumped in so that someone else other than the subscriber is paying for the service, then I agree with you. but that's not the metric most people use when they discuss being profitable