[asterisk-biz] satellite & voip providers

[James Sharp]

On Tue, 10 Jan 2006, Mark wrote:

> monitors (leaving to the satellite and the return from the satellite) That 
> delay would apply that to voice packets both coming and going, and I really 
> dont know how anyone could carry on a normal phone conversation under those 
> circumstances..

I guess I should have qualified my entire question.  It was late and I was 
half-asleep.

I work for a satellite company and we already have uplink facilities and 
space segments on several satellites (Including Intelsat 701, that can see 
out into Africa and parts of the Middle East from our uplink on the US 
East Coast).  I'm trying to get a feel for the market to see if its worth 
our time pursuing clients and customers in those areas for voip 
termination.

We have numerous clients on our domestic links that run voip to their 
mobile satellite trucks/trailers with 500-600ms latencies without a 
problem, so I'm not worried about that.  As long as the latency stays 
consistent, there's no problem with voice quality.

>
> Of course you could make your own calculations however the distance of a 
> geosynchronous satellite is 27,300 (possibly 23,700 as I do not recall 
> exactly) miles above the equator, and factoring the speed of light. Keep in 
> mind that the further you are from the equator that distance greatly 
> increases and the Earth is also curved. There is sometimes additional latency 
> introduced at the satellite.

Right.  Slant range and all that.  Cursed speed of light.  Curse you, 
Einstein!

> There are low earth orbit satellites such as Iridium. In fact I once made an 
> Iridium phone call, and the latency was barely more than an international 
> long distance call.. The advantage of low earth orbit satellites is that the 
> latency is greatly reduced, as the distance is less.

Irridium is damn expensive though.  Almost $2 a minute.

>
> I know that Sprint several years back started a low earth orbit internet and 
> phone service. It was abandoned only a short time later as I recall. I think 
> it is about time that the tecnology gets revisited.
>
> Bringing lower latency internet to the world via low earth orbit satellites 
> would be a potentially huge global market. Low earth orbit satellites circle 
> the globe, so once the sattellites are in place, serving Africa is no 
> different from serving the USA. Geosyncronous or Geostationary satellites 
> remain in the same place relative to the earth, and maintain a higher orbit.

There's people like Irridium and Globalstar shooting at the LEO market, 
but then there's Hughes aiming at hand-held terminals pointing at 
high-power/high-sensitivity geosync birds.