SatPhones — Why Can't They Make It Work? 337
RedEaredSlider writes "Satellite phones aren't as clunky as they once were, and technology has made them more powerful. Gone are the days when satellite phones had to be accompanied by a suitcase. Yet to date, the field is littered with bold attempts at a phone that could be used anywhere, without depending on earthbound cell phone networks. Billions have been invested, with relatively little to show for it. Part of the answer is debt. TerreStar is only the latest casualty of a crushing $1.2 billion debt load. The company introduced its Genus phone last month, but is in the middle of Chapter 11 proceedings. It's unclear that the phone will sell enough to help TerreStar stay in business, especially when it carries a $799 price tag."
Can't make a call from inside (Score:5, Informative)
Re:Do they still use geostationary satellites? (Score:5, Informative)
Iridium satellites are at 475 miles, not geo sync
Re:Can't make a call from inside (Score:5, Informative)
Re:Can't make a call from inside (Score:4, Informative)
Few satellites use an RTG. Too high a risk of the radioactive material being released into the atmosphere if something goes wrong. Really hard for private companies to get the clearance to use them. It looks to me like most satellites using RTGs are government-backed.
Re:It's a tough business plan, but they do work (Score:4, Informative)
What I'd like to see is a LEO network with satellites as cheap as possible that provide store and forward text/data messages only.
That's what the Iridum pager [wcclp.com] does.
Re:Do they still use geostationary satellites? (Score:3, Informative)
TerreStar, Sky Terra (Lightsquared), and Inmarsat use geostationary satellites. Iridium and GlobalStar use low earth orbits (below 1000 km ), while ICO Global initially opted for satellites in a medium earth orbit, at about 10,000 km. ICO's latest bird, however, will be geosynchronous.
Re:It's not cost effective. (Score:5, Informative)
It's not a direct comparison, AT&T-s network has a much higher aggregate capacity.
The Iridium satellites can only handle 1100 concurrent phone calls each. While there are 66 active satellites, most of the coverage is over the poles because of their orbits, so the capacity over occupied land is much lower than one would think, probably below 10,000 concurrent calls. Each of those channels in turn is very narrow bandwidth, about 2400 bits per second, and uses heavy audio compression to make speech intelligible. This explains why Iridium plans are so expensive. They're not for "chatting", they're for professionals that need emergency communication in the middle of nowhere.
The iPhone in my pocket has a higher bandwidth for a single connection than an entire Iridium satellite!
Re:Do they still use geostationary satellites? (Score:4, Informative)
I think that the problem with these phones and why they will never take off is that they will never be cheap enough for mere mortals to use. They just don't have enough bandwidth to have the unwashed masses using it to talk about the latest celeb gossip. With a space based solution, it would be hard to break geographic areas into cells like what is currently done with cell phone tech. The result is that everyone is on the same tower, and there is only so much signal to go around. Because supply is so tight, price has to remain high.
Re:Can't make a call from inside (Score:4, Informative)
For us armchair rocket scientists, an RTG [wikipedia.org] is also known as a nuclear battery.