If it's not tilted, that sounds like a squirrel and bird platform. -----Original Message----- From: AF <af-boun...@af.afmug.com> On Behalf Of Robert Andrews Sent: Wednesday, July 15, 2020 5:18 PM To: af@af.afmug.com Subject: Re: [AFMUG] OT: Details on the Starlink router
What I noticed is the flat surface of the "UFO".. Gonna get some snow on that without a heater... On 07/15/2020 12:00 PM, Ken Hohhof wrote: > So are they looking at it from the mobile wireless perspective, where > speeds are aspirational, “up to”, or “on a good day”? Or from the > home Internet perspective, where people run speedtests and bitch if > they don’t get what they’re paying for? > > Who has ever gotten a refund or cancelled a 12 month contract on a > cellphone because the speed didn’t match the marketing? > > And of course with any new service, whether it’s satellite or 5G, the > early adopters will probably get fantastic speeds because there’s > nobody else on the network. Let’s face it, WISPs do this too. Who > hasn’t had a new WISP pop up in your area advertising speeds that > sound like every subscriber gets the full capacity of the AP at max > modulation. And how many reviews do you see that say the WISP was > fast at first and then the speeds just got slower and slower. > > *From:* AF <af-boun...@af.afmug.com> *On Behalf Of *Adam Moffett > *Sent:* Wednesday, July 15, 2020 1:42 PM > *To:* af@af.afmug.com > *Subject:* Re: [AFMUG] OT: Details on the Starlink router > > The FCC allowed them 2Ghz of bandwidth for the satellite to user > terminal. 20Gbps must assume 10 bits/hz. Or maybe they mean a > different sense of "capacity". The journalistic sources are never > precise about these things. > > I've been assuming that just like any other wireless you can't put the > same channel into the exact same location at the same time, or else > they would interfere. So they might simplify and say "20 Gbps per > satellite", but I think it's really going to be "20Gbps for a given > geographic area". I don't know how big that area will be, but the > smaller the satellite is, the smaller the antenna has to be, and then > of course the wider the beam is. I imagine each satellite won't use > the full 2ghz, but maybe dozens of satellites over a certain area will > each use their own non-interfering chunk. > > ....I'll freely admit that I'm filling in blanks left by the articles > I've seen. Maybe there are additional details to explain how they're > solving these problems, but I suspect the 20Gb per satellite is not > going to be meaningful. It'll be 20Gb total for a region of some size. > > On 7/15/2020 1:32 PM, Colin Stanners wrote: > > Doing some math: > > 40K subscribers on 60 satellites is 666 subs/satellite if equally > loaded. But load is far from equal, the planet surface is 70% water. > I don't know how much the "standard" orbit is over water but let's > say 50% as it's further from the poles. Say that at any point in > time, around half the satellites will be barely useful (except for > cruise ships, and overseas aircraft service) due to being over water > and ground obstructions. > > So a more accurate number is 1300 subs/well-positioned satellite, > assuming for simplicity that subs are equally physically spread out. > > The numbers that I saw state that every satellite has 20Gbps > capacity, let's assume that that is downlink subscriber capacity at > maximum modulation, and that the backhaul to the ground station is > fully available to that satellite and also 20Gbps at max modulation. > 20Gbps / 1300 subs is 15mbit per sub, assuming that everyone's using > it simultaneously. > > But there are the issues with wireless in general, added to those > about customer self-installs (shudder), and satellite service: > mainly subs having trees or obstructions in the way, blocking or > reducing LoS to at least part of the sky where their hand-off > satellite should be, and rain. I'd say that altogether that a more > realistic number with those is 8-12mbit per user. > > Being generous, 12Mbit average per sub: not bad these days, > considering the traffic patterns at peak time (1/3rd subscribers > using Netflix / D+ / etc with 1-3 streams at HD or 4K) I'd assume > that from that they could sell mostly 30-70mbit download speed plans > without too much consternation. But as traffic keeps increasing, > over time they may run out of capacity for the higher plans and > decide to reduce. > > On Wed, Jul 15, 2020 at 11:58 AM Bill Prince <part15...@gmail.com > <mailto:part15...@gmail.com>> wrote: > > There are some details in this story that were new to me. One of > the > ones that popped up was that each group of 60 Starlink > satellites is > expected to support ~~ 40,000 subscribers. > > That puts the 800 satellite "moderate service level" at > supporting about > half a million subscribers (~~ 533,000). > > In order to support a million subscribers, they will need about > 1500 > satellites. > > > https://www.tesmanian.com/blogs/tesmanian-blog/starlink-router-fcc?_po > s=19&_sid=a6c7fff07&_ss=r > > -- > > bp > <part15sbs{at}gmail{dot}com> > > > -- > AF mailing list > AF@af.afmug.com <mailto:AF@af.afmug.com> > http://af.afmug.com/mailman/listinfo/af_af.afmug.com > > > > > -- AF mailing list AF@af.afmug.com http://af.afmug.com/mailman/listinfo/af_af.afmug.com -- AF mailing list AF@af.afmug.com http://af.afmug.com/mailman/listinfo/af_af.afmug.com
