Most serious HFT moved to shortwave type links a while back, the microwave path between the CME and New Jersey is obsolete... Think big ass yagi-uda antennas, dipoles, much lower frequencies, very low data rates.
On Sat, Jun 15, 2019 at 4:02 PM Bill Prince <part15...@gmail.com> wrote: > This is the best explanation I've seen (so far) of how the system is > expected to work. One thing I didn't think about was the low latency. This > video speculates that it will have lower latency than trans-Atlantic fiber. > Ergo, this may become the new darling of flash traders. > > https://www.youtube.com/watch?v=giQ8xEWjnBs > > bp > <part15sbs{at}gmail{dot}com> > > > On 6/3/2019 11:19 AM, ch...@wbmfg.com wrote: > > I wonder how snow on the cpe antenna will affect things. > > *From:* Bill Prince > *Sent:* Monday, June 3, 2019 12:16 PM > *To:* af@af.afmug.com > *Subject:* Re: [AFMUG] SpaceX Says Its 60 Starlink Satellites Are All > Phoning Home (and Fading Out) | Space > > > That would be per satellite. So it doesn't really tell us what the system > capacity is. Don't forget there will be ~ 600 satellites per ring, and (I > think) 24 rings. > > > > bp > <part15sbs{at}gmail{dot}com> > > > On 6/3/2019 10:18 AM, Adam Moffett wrote: > > People always ask about system capacity, but it's simpler than that. > Their FCC filings show 2ghz of spectrum for the downlink from satellite to > user terminal. They have two polarities, not unlike us. We could > generously assume they'll get 10 bits/hz. That's 20gbps in a given > geographic area. It doesn't matter how many satellites there are, or what > the capacity of a given satellite is. I don't know how big that geographic > area will be exactly. > > -Adam > > > On 6/2/2019 6:15 PM, Bill Prince wrote: > > There are whole bunches of risk factors. > > Assuming the satellite-mesh system works (and that is still an if; note > that this first batch does not include the sat-sat laser link capability), > I have not seen a real estimate of the system capacity. I would presume > there would be separate earth stations for each orbital plane. There could > even conceivably be multiple earth stations for each orbital plane, which > would make the system capacity flexible. > > IDK if they're making money or not, but they are serving body blows to the > competition. > > There was open speculation that the Falcon heavy was going into a limited > demand situation, but now that it seems to be working (so far), that market > opportunity may be shifting as well. > > > > bp > <part15sbs{at}gmail{dot}com> > > > On 6/2/2019 12:52 PM, Ken Hohhof wrote: > > You’d think that SpaceX is highly profitable and is using those profits to > expand into the satellite Internet business. But actually there is debate > whether SpaceX is profitable without accounting tricks, and even if it is > profitable, the margins are very thin. Reportedly the geostationary launch > business is softening, and SpaceX is actually looking to Starlink for > profits. No doubt it helps if you can launch your own satellites, maybe > even having them ride along while you get paid to launch stuff for paying > customers. But this sounds like a pretty risky venture, paid for with > borrowed money. If it wasn’t risky, it wouldn’t be Elon, right? > > > > > > *From:* AF mailto:af-boun...@af.afmug.com *On Behalf Of *Mike Hammett > *Sent:* Sunday, June 2, 2019 12:04 PM > *To:* AnimalFarm Microwave Users Group mailto:af@af.afmug.com > *Subject:* Re: [AFMUG] SpaceX Says Its 60 Starlink Satellites Are All > Phoning Home (and Fading Out) | Space > > > > I would suspect they are going to have hundreds of earth stations as > opposed to one or two earth stations that legacy platforms have. Up to the > bird, maybe across one or two birds, and back down to the fiber-fed earth > stations. I've seen the numbers, but I forgot the numbers. It's real > bandwidth at each one. > > > > ----- > Mike Hammett > Intelligent Computing Solutions <http://www.ics-il.com/> > <https://www.facebook.com/ICSIL> > <https://plus.google.com/+IntelligentComputingSolutionsDeKalb> > <https://www.linkedin.com/company/intelligent-computing-solutions> > <https://twitter.com/ICSIL> > Midwest Internet Exchange <http://www.midwest-ix.com/> > <https://www.facebook.com/mdwestix> > <https://www.linkedin.com/company/midwest-internet-exchange> > <https://twitter.com/mdwestix> > The Brothers WISP <http://www.thebrotherswisp.com/> > <https://www.facebook.com/thebrotherswisp> > > > <https://www.youtube.com/channel/UCXSdfxQv7SpoRQYNyLwntZg> > ------------------------------ > > *From: *"Tim Withrow via AF" <af@af.afmug.com> > *To: *af@af.afmug.com > *Cc: *"Tim Withrow" <timwith...@aol.com> > *Sent: *Saturday, June 1, 2019 4:43:01 PM > *Subject: *Re: [AFMUG] SpaceX Says Its 60 Starlink Satellites Are All > Phoning Home (and Fading Out) | Space > > What kind of bandwidth capacity could each satellite have at any given > point? > What is the usable bandwidth of their system? Who makes a radio that big > to carry/transmit such capacity or is it an > aggregate of small radio's? > > > ------------------------------ > > On Saturday, June 1, 2019 Bill Prince <af@af.afmug.com> wrote: > > Naturally, we're all thinking about what effect this will have in rural > America, but I am also wondering if this would have some effect on China's > "great firewall"? > > > > bp > > <part15sbs{at}gmail{dot}com> > > > > On 6/1/2019 1:47 PM, Ken Hohhof wrote: > > I think one factor advocacy groups and govt critters need to keep in mind > is that instead of robust competition, what could occur is “disruptive” > pricing, having the effect of discouraging or bankrupting the competition. > And now some new entrant is the only game in town. And if it turns out to > be unreliable, or not to have enough capacity, or their speeds are > actually best effort, or their satellites start dropping out of the sky, or > whatever, people can’t switch back to their old provider. Like being > dissatisfied with online stores and assuming you can always switch back to > the old brick and mortar store, from Uber and Lyft back to taxis and > limos. Sorry, they don’t exist anymore. > > > > This is unlikely to happen in big cities, I doubt Comcast will go bankrupt > because of Starlink. But to just assume there will be lots of choices out > in the middle of nowhere driving the price down without any of them turning > off the lights, seems a little naïve. > > > > And to assume big megacorps like SpaceX, Amazon, Googe, Facebook, etc. > would never price below cost to be “disruptive” also seems naïve. > > > > > > *From:* AF mailto:af-boun...@af.afmug.com *On Behalf Of *Bill Prince > *Sent:* Saturday, June 1, 2019 3:20 PM > *To:* af@af.afmug.com > *Subject:* Re: [AFMUG] SpaceX Says Its 60 Starlink Satellites Are All > Phoning Home (and Fading Out) | Space > > > > Sure. But after the clouds, geostationary still needs to go another 23,000 > miles. LEO only has to go a few hundred. > > > > bp > > <part15sbs{at}gmail{dot}com> > > > > On 6/1/2019 10:47 AM, Mathew Howard wrote: > > Clouds are generally a lot lower than a couple hundred miles... > > > > On Sat, Jun 1, 2019, 10:58 AM Bill Prince <part15...@gmail.com> wrote: > > Maybe at geostationary distances, but these are only a few hundred miles > up. > > bp > <part15sbs{at}gmail{dot}com> > > On 6/1/2019 8:56 AM, Matt Hoppes wrote: > > Don't those bands have significant attenuation issues with like... > > clouds? > > > > On 6/1/19 10:55 AM, Bill Prince wrote: > >> According to Wikipedia, they will be on Ku, Ka, and V bands. > >> > >> https://en.wikipedia.org/wiki/Starlink_(satellite_constellation) > >> > >> bp > >> <part15sbs{at}gmail{dot}com> > >> > >> On 6/1/2019 7:46 AM, Jaime Solorza wrote: > >>> Wonder what frequencies they will use? > >>> > >>> > https://www.space.com/spacex-starlink-satellites-phone-home-dimming.html > >>> > >>> > >> > > -- > 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 > > > -- > 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 > > -- > AF mailing list > AF@af.afmug.com > http://af.afmug.com/mailman/listinfo/af_af.afmug.com >
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