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Bwana
01-29-2011, 07:45 AM
So have any of you had any experience with satellite phones? I have been throwing around the idea of picking one up, but they seem kind of limited. When I first started looking into it, I called globalstar. http://www.globalstar.com/en/

Before looking into it, I assumed you could just make a call whenever. Upon further review, it would seem one must wait for a satellite to pass over and you can only make calls for a limited time. http://calltimes.globalstar.com/

With all the time I spend way the hell back in the mountains and walking around the jungle once in awhile, I was thinking about it as a decent saftey tool.

I'm also considering one of these, a GPS satellite locator. http://www.findmespot.com/en/index.php?cid=102

Have any of you had any experience with these?

tmax63
01-29-2011, 07:48 AM
I've heard good things about the GPS beacons in the back country but have never used them.

RedNeckRaider
01-29-2011, 07:50 AM
I was wondering about those. My son is back in Bagdad and I thought about one to talk to him would be cool. Phone lines are spotty and we use Skype. I will track this thread and maybe get some info from the smart people :)

Bwana
01-29-2011, 07:50 AM
I've heard good things about the GPS beacons in the back country but have never used them.

My brother just picked one up and loves it, but I have never used one, or a satellite phone for that matter. :shrug:

bevischief
01-29-2011, 08:37 AM
I thought there was one satellite provider that was working with one the big cell phone companies to increase coverage...

Bwana
01-29-2011, 09:01 AM
I thought there was one satellite provider that was working with one the big cell phone companies to increase coverage...

I'm not sure about that bevischief.

When I was talking to Globelstar earlier in the week, in theory, they are getting ready to launch 5 or 6 more satellite's this year to increase coverage. With that being said, I don't necessarily buy into that. Right now, the coverage is sketchy at best.

Buehler445
01-29-2011, 09:16 AM
The GPS beacon is a pretty smart idea. There should be pretty decent coverage on it. They use it for our tractor guidance and there are anywhere between 10-20 passing over the skies all the time (or else the guidance wouldn't work).

I'm sure the satphone satellites are different, but it's weird to me that there wouldn't be good coverage out there.

RedNeckRaider
01-29-2011, 09:24 AM
If the price is right I might be interested. My son is a contractor and is always on the FOB. That allows us to stay in touch but it would be nice for him to have a reliable cell phone. The bullshit raghead cell phones are a rip off~

vailpass
01-29-2011, 11:30 AM
Iridium

Bwana
01-29-2011, 11:32 AM
Iridium

Expand on that, if you would?

Dartgod
01-29-2011, 12:00 PM
I had one once, but a dinosaur ate it. I found it later in a pile of dinosaur dung, but I didn't really want to use it anymore after that.

Bwana
01-29-2011, 01:50 PM
I had one once, but a dinosaur ate it. I found it later in a pile of dinosaur dung, but I didn't really want to use it anymore after that.

Dude, I knew you were getting long in the tooth, but I didn't think you were THAT old. :evil:

RippedmyFlesh
01-29-2011, 03:15 PM
I guess this explains the moving target.
You need LEO because you may not always be able to get a clear shot at a sat.
The list of places you CAN'T have one was intresting


Satellite phone network
Geosynchronous satellites



Some satellite phones use satellites in geostationary orbit, which are meant to remain in a fixed position in the sky. These systems can maintain near-continuous global coverage with only three or four satellites, reducing the launch costs. The satellites used for these systems are very heavy (approx. 5000 kg) and expensive to build and launch. The satellites sit at an altitude of about 22,000 miles (35,000 km); a noticeable delay is present while making a phone call or using data services due to the large distance from users. The amount of bandwidth available on these systems is substantially higher than that of the Low Earth Orbit (LEO) systems; all three active systems provide portable satellite Internet using laptop-sized terminals with speeds ranging from 60 to 512 kbits per second (kbps).

Another disadvantage of geostationary satellite systems is that in many areas—even where a large amount of open sky is present—the line-of-sight between the phone and the satellite is broken by obstacles such as steep hills and forest. The user will need to find an area with line-of-sight before using the phone. This is not the case with LEO services: even if the signal is blocked by an obstacle, one can wait a few minutes until another satellite passes overhead, but a moving LEO may drop a call when line of sight is lost.

* ACeS: This small regional operator provides voice and data services in East Asia using a single satellite.
* Inmarsat: The oldest satellite phone operator, founded in 1979. It originally provided large fixed installations for ships, but has recently entered the market of hand-held phones in a joint venture with ACeS. The company operates eleven satellites, with another planned for launch in 2010. Coverage is available on most of the Earth, except polar regions.
* Thuraya: A system based in the UAE. Three satellites are currently in service that provide coverage to the most of Eurasia, Africa and Australia. There is some degree of coverage overlap between adjacent satellites within the network.
* MSAT / SkyTerra: An American satellite phone company that uses equipment similar to Inmarsat, but plans to launch a service using hand-held devices in the Americas similar to Thuraya's.
* Terrestar: Satellite phone system for North America
* ICO Global Communications: A satellite phone company which has launched a single geosynchronous satellite which is not yet active.

[edit] Low Earth orbit

LEO telephones utilizes LEO (low Earth orbit) satellite technology. The advantages include providing worldwide wireless coverage with no gaps. LEO satellites orbit the earth in high speed, low altitude orbits with an orbital time of 70–100 minutes, an altitude of 640 to 1120 kilometers (400 to 700 miles), and provide coverage cells of about (at a 100-minute orbital period) 2800 km in radius (about 1740 mi). Since the satellites are not geosynchronous, they must fly complete orbits. At least one satellite must have line-of-sight to every coverage area at all times to guarantee coverage. Depending on the positions of both the satellite and terminal, a usable pass of an individual LEO satellite will typically last 4–15 minutes on average;[3] thus, a constellation of satellites is required to maintain coverage (as is done with Iridium, Globalstar, GPS, and others).

Two such systems, both based in the United States started in the late 1990s but soon went into bankruptcy after failing to gain enough subscribers to fund launch costs. They are now operated by new owners who bought the assets for a fraction of their original cost, and are now both planning to launch replacement constellations supporting higher bandwidth. Data speeds for current networks are between 2200 bit/s and 9600 bit/s using a satellite handset.

* Globalstar: A network covering most of the world's landmass using 44 active satellites; however many areas are left without coverage since a satellite must be in range of an earth station. Satellites fly in an inclined orbit of 52 degrees, so polar regions cannot be covered. The network went into limited commercial service at the end of 1999 .
* Iridium: A network operating 66 satellites in a polar orbit that claims coverage everywhere on Earth. Commercial service started in November 1998 and fell into bankruptcy soon after. In 2001, service was re-established by a new company. Radio cross-links are used between satellites to relay data to the nearest satellite with a connection to an earth station.

[edit] Tracking

LEO systems have the ability to track a mobile unit's location using doppler shift calculations from the satellite.[4] However, this method can be inaccurate by tens of kilometers. On some Iridium hardware the coordinates can be extracted using AT commands, while recent Globalstar handsets will display them on the screen.[5]
[edit] Locations banning satellite phones

In some countries possession of a satellite phone is illegal.[6] Their signals will usually bypass local telecoms systems, hindering censorship and wiretapping attempts. These countries tend to score low on the Democracy index, with the exception of India, so a ban can be the result of the state's desire for mass surveillance or that it lacks the technology to intercept satellite phone traffic.

* North Korea
* India - Proper permission required [7][8][9]
* Cuba[citation needed]
* Libya[citation needed]
* Burma [10]

Satellite phones are legal in most countries and are not disfavoured by many governments. In Australia, residents of remote areas may apply for a government subsidy for a satellite phone.[11]


http://en.wikipedia.org/wiki/Satellite_phone

vailpass
01-29-2011, 05:26 PM
Expand on that, if you would?

A former business partner of mine wasinvolved with the original Iridium project when he was at Motorola here in Phoenix before it went bankrupt. Iridium is now restructured and strong.
Iridium /General Dynamics is a very solid group of engineers.
Their phones are not inexpensive but are the highest quality.

http://www.iridium.com/Products.aspx

googlegoogle
01-29-2011, 05:31 PM
I know when the shit hits the fan that those types of phones might be the only ones that work.

Not that expensive. I just wonder what the monthly bill is.
http://www.satphonestore.com/

Bwana
01-29-2011, 05:48 PM
I know when the shit hits the fan that those types of phones might be the only ones that work.

Not that expensive. I just wonder what the monthly bill is.
http://www.satphonestore.com/

It depends. Globalstar has a two hundred and forty dollar deal for a year, for two models, one of which you can pick up for nothing on Ebay. The problem with them is, their service seems to blow. (A real hit and miss) I don't want to be laying at the base of a cliff after a dust up with a grizzy and having to wait an hour before one of their birds flys over. Vailpass seems to be right about Iridium and their coverage. You get a lot better coverage, but shit oh dear on the price.

You can buy pre-paid minutes with others, but they expire fast and are a shit load of money, if you're not using it all the time. I still don't know what the answer is, but I will be doing a lot more research, before I make up my mind on this one. There is some good information on here, that some of you dug up as well. Well played gents, well played indeed! :thumb:

Bwana
01-31-2011, 01:58 PM
Bump for Monday crew, any advise on this?