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O3b satellite network
3rd Jun, 2017 at 11:09am
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The O3b satellite network comprises multiple satellites in orbit directly above the equator. They are at 8064 km altitude and are moving eastwards. As satellites set in the east, others rise in the west. To operate you need 2 tracking antennas.
The satellite has 12 tracking antennas, each pointing at an earth station.



The image above is intended to give an impression of how it works. See http://www.satsig.net/O3b/O3b-orbit.htm for an animation.

Eric
« Last Edit: 9th Feb, 2018 at 11:30am by Admin1 »  

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Re: O3b satellite network
Reply #1 - 15th Jul, 2017 at 6:10pm
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It looks like that some territory on the earth are out of signal from that four satellites for a couple of hours !!!
Would you please explain the advantage of these shifting satellites  over Geo-stationary satellites( which provides continuous communication).
Thanking you.
  
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Re: O3b satellite network
Reply #2 - 16th Jul, 2017 at 1:29pm
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The O3b network is not intended to provide service in the polar regions. Its satellites orbit along above the equator and are not visible from the polar regions.

There are sufficient satellites in the O3b network to provide continuous service in the intended service area, plus and minus either way from the equator, and there are at least 2 visible satellites above the horizon at any time.

See this page and picture http://www.satsig.net/africa/algeria/vsat-installer-o3b-algeria.htm


Each earth station site has two tracking antennas.

My animation only shows a limited number of satellite. In reality there are more satellites around and above the equator, always moving eastwards.

Beyond the north and south extremes of the 24/7 coverage area, satellites will be visible for short periods and further north or south, not visible at all. Run the simulation and look to see where are the north-south latitude limits of the coverage. Experiment by increasing or reducing the simulated satellite height.

The key advantage of the O3b network is its low latency (low time delay) due to its lower orbit distance as compared with geo-stationary. Latency affects the standard two-way internet protocol, making web pages slower to load. For geo satellites special protocols are used to speed up web pages and downloads. A web page may suffer second or so initial delay and then suddenly the whole lot comes quickly.

O3b is similar to terrestrial fibre, both with regard to short latency and also very high speed bit rates. It is attractive to ISPs serving towns, communities, large cruise ships etc.

Best regards, Eric.
« Last Edit: 9th Feb, 2018 at 11:31am by Admin1 »  

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Re: O3b satellite network
Reply #3 - 18th Jul, 2017 at 12:10pm
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To avoid confusion, I have spent some time working on the software that generates the animation picture of the O3b beams.


The output now shows 9 satellites moving along at 40 deg increments above the equator.

Hope it works OK. Test it here: http://www.satsig.net/O3b/O3b-orbit.htm
Please tell me if you see problems. There is still a maths bug with large size beams, e.g. 27cm satellite antenna and 1.5 GHz frequency. I know about it but not fixed!.
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Re: O3b satellite network
Reply #4 - 18th Jul, 2017 at 4:28pm
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Sorry Admin1
Actually I made the comment on the basis of 5 satellites those you showed. Thanks for clarifying the secret.
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Re: O3b satellite network
Reply #5 - 5th Aug, 2017 at 5:55pm
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Actually their main claim is the lower latency, which is a plus for VoIP/telephone backhaul. But it is not a cheap system to use! I hear complaints from the Cook Islands that pricing didn't come down with O3B. And of course, one expensive installation only serves one single island; and you still face the cost of a system to distribute it. Expensive multiple tracking antennas have to be a bit of a nightmare for reliability and maintenance in REMOTE places.

I also don't see any reason why it would be much faster, at least not faster than the new HTS satellites.

I'd love to see price comparisons between O3B, conventional GEO's and HTS's, bot wholesale and retail. I hear that O3B is rather secretive about their own pricing.

My 2 cts.

Christian
  
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Re: O3b satellite network
Reply #6 - 6th Aug, 2017 at 12:30pm
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I too would be very interested in a price comparison between GEO, GEO-HTS, MEO and LEO systems, and cable.

To get started here are a few thoughts about O3b. Regarding financials, I read this from 10 Dec 2015.

http://spacenews.com/o3b-orders-eight-more-satellites-from-thales-alenia-space/

Each O3b satellite has 10 customer spot beams. Each customer beam has one transponder with 215 MHz bandwidth. Assuming 8PSK modulation and 3/4 FEC, each customer beam provides a download bit rate of 486 Mbit/s.

The reference above hopes that each satellite will produce $35 million revenue per year. That is $3.5 million per beam per year or $291,000 per month or $600 per Mbit/s per month. Is that calculation right ?

Each customer therefore needs to pay $291,000 per month and gets the full 486 Mbit/s and this then needs to be shared out locally amongst other people in the local town, island, community, cruise ship or aircraft carrier etc.  486 Mbit/s is good for some 13,800 domestic end user customers each paying $35 per month. So customer total income = $483,000 per month, which more than pays for the satellite capacity.

This is all assuming the maximum 13,800 end users per customer. Once you start to consider the start up and growth phase with fewer end user customers you get worse results.

Does any of this make sense ?

  

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Re: O3b satellite network - lowest beam elevation angle
Reply #7 - 26th Mar, 2018 at 3:06pm
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Does anyone know at what low elevation angle are the beams lifted up and re-pointed eastwards ?

  

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