Nice...8x300Gbit optical beams; that's awesome.
On Fri, May 17, 2013 at 11:33 AM, Warren Bailey < wbai...@satelliteintelligencegroup.com> wrote: > Super high frequency stuff is already in space. Iridium uses ka for > their space craft to space craft routing network. Not much attenuation in a > vacuum.. ;) > > Look up vortex beams. These guys should hook up with the vortex guys. > They were getting like 40bits to hertz using oam. > > > Sent from my Mobile Device. > > > -------- Original message -------- > From: Phil Fagan <philfa...@gmail.com> > Date: 05/17/2013 10:29 AM (GMT-08:00) > To: Warren Bailey <wbai...@satelliteintelligencegroup.com> > Cc: Carsten Bormann <c...@tzi.org>,NANOG list <nanog@nanog.org> > Subject: Re: 40 GBit @ 240 GHz across 1 km LoS > > > Well put; 1kM is a giant leap from .1Km, but its a far cry from rural > transport. > > I wonder what the fixed mobile/metro use cases might look like; > Alternate path, aggregate short distance media backhaul... > > I think I like the idea most for non-earth atmosphere use cases, space > vehicle or exploration vehicle use. > > Can you blast your way through rain, snow, or hell...a sandstorm by > increasing your power? > > > On Fri, May 17, 2013 at 10:44 AM, Warren Bailey < > wbai...@satelliteintelligencegroup.com> wrote: > >> I disagree. >> >> It's not the near field stuff that is an issue.. It's the far field stuff >> further down the road that is going to murder the link.. Look at his Fig 1 >> and Fig 2. >> >> Fig 1 is saying that he is getting killed at 50mm/h of rain at 60 gig and >> at 175 gig. Fig 2 is saying that everything works well until you exceed >> .1km - where real life kicks back in. His clear sky is normal for anything >> wireless, but look at what happens at distances exceeding his comfort >> zone. From .1km to 1km he's taking 30-50dB of loss on his link. I don't >> know what kind of transmitter he has, but *IF* he were to encounter rain I >> sure as hell hope he has a form of transmit power control. I also noticed >> that they're using OOK, which is much better than FSK but runs the risk of >> being clobbered by a relatively small amount of noise. >> >> So yes, this is awesome for running huge data rates across the street. >> Down the road, you may have a few bad days. >> >> On 5/17/13 8:22 AM, "Carsten Bormann" <c...@tzi.org> wrote: >> >> >On May 17, 2013, at 16:30, Warren Bailey >> ><wbai...@satelliteintelligencegroup.com> wrote: >> > >> >> By not working. At those frequencies you're talking a light moisture >> >>pocket taking the entire link down. >> > >> >Not quite as bad: >> > >> > >> http://www.uni-stuttgart.de/int/institut/MA_Publikationen/reichart/COMCAS_ >> >25G_link.pdf >> > >> >The ~ 50 mm/h rain they seem to budget for is not yet quite an "end of >> >the world" torrent, but it's not like you sneeze and the link goes down. >> >(And if you have more than 50 mm/h sustained, you've got a much, much >> >bigger problem :-) >> > >> >Grüße, Carsten >> > >> >> >> > > > -- > Phil Fagan > Denver, CO > 970-480-7618 > -- Phil Fagan Denver, CO 970-480-7618
