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A Private GSM Cell?
mr number two asks: "I live in the mountains and have poor GSM reception. I can buy an active repeater to boost signal strength in my home to good levels, but what I'd really like to do is have a private GSM picocell, such that at home I would be connected to my own PBX. Calls to my home phone number would ring through to my cell phone. I wouldn't have to worry about a home cordless phone (and 802.11 interference) and I'd have all my speed dialing / contacts info right there. There are many other benefits. Ignoring FCC licensing issues, is there a base station I can purchase which has a signalling interface that will interface to a small PBX?"
This looks like it might be helpful:
http://www.voip-info.org/wiki-VOIP+GSM+Gateways
The site www.voip-info.org itself looked promising during my brief visit....
Everything is available for a price.
On the other hand, I might suggest searching for a solution that does not ignore the rules. Rules for communication systems are (for the most part) fairly sane. The avoid pesky things such as cross talk, interference, etc. But hey, this is Slash, who really cares about that kind of thing ;)
-- www.WhereHaveIBeen.com
they seem to sell alot of different equipment. www.tessco.com
Si vis pacem, para bellum! For evil to succeed good men need only do nothing!
Sure. You can do what you want but the hardware is incredibly expensive and you'd need a license to operate as a telecoms provider which also is incredibly expensive. If you're looking for a way to reduce your cell phone bills then this isn't it.
Since you're going to be operating a transmitter it's not going to be too hard to find out where that rogue cell signal is coming from either.
Don't think that they won't notice because you're up in the moutains. People are employed to drive around with a pile equipement and do site surveys. There was an article with pics about it recently.
There are two options, either of which avoids the problem, either 900Mhz or 5Ghz (you weren't planning on deploying 802.11a were you ?)
Please tell me you didn't go out and buy the coolest phone a few years back in the 2.4Ghz range, and now aren't willing to "upgrade" to a 5Ghz phone.
I have mod points and I am not afraid to use them
Administering a wireless telecommunications switch, I have to ask: do you want a network of your own with no ties to other carriers, or just a cell?
If you're looking for a "just you" thing, good luck. The GSM standards are pretty easy to get your hands on, and with a little ingenuity, you could build a GSM switch. It's basically a few DBs and hardware interfaces. That's where things get tricky. GSM cells (which you could easily purchase for $100,000 (CDN)) need to communicate to the switch using a standardized protocol over T1. So you'd have to build THAT network stack over some sort of Frame-Relay-over-T1 interface (which are often rather expensive in and of themselves... also, good luck with Linux drivers...).
I left out the possibility of buying a GSM switch, because I doubt you'd be on Ask Slashdot if you had that kind of cash.
Now I know you said "apart from FCC regulations" or something, but that's what's going to kill you. GSM uses a 200KHz carrier (at least with the 800 and 900 MHz spectrum), and to put a site on the air with any sort of wattage in any location of any use (you are in rough terrain, no? So you'd put in on a peak... and spread your signal pretty far) without interfering with anyone else and without the FCC turning your way is going to be quite tricky.
Karma: Raspberry Kiwi
I have a problem with mosquitoes in my yard and I wonder if anyone has some good advice on the best kind of cannon and ammo I should get to shoot them down?
"It's a wonderful idea. But it doesn't work." -- Tad Danielewski
Ignoring FCC licensing issues
That could get you a 6 x 9 cell with a roommate.
Speak to a GSM network providor, like Vodaphone, Orange, O2 or something (to give UK examples). All of these providors will sell you a local cell unit, its a service they provide to companies with large sites or campuses, to use mobile phones instead of DECT phones across a wide area with automatic roaming off site. Calls within the same cell are free, with a annual rental, and calls off the local cell are charged at the standard airtime rate, and the bonus is that its just a normal mobile cell.
"Hi! I live in a cave and have voices in my head telling me to kill people. I can pay my local prostitute to feign death, but what I'd really like to do is have a private basement pit, such that at home I would be able to do my murders undisturbed. I wouldn't have to worry about getting blood over my slacks, and I'd have all my brain-sized stewing pots right there. There are many other benefits. Ignoring local anti-murder laws, is there a particular type of teen hitch-hiker it's better to prey on?"
~~~~~ BigLig2? You mean there's another one of me?
T-Mobile has been rumored to offer in-home VoIP service in the fall of 2005. It wouldn't be legal for you to run your own "picocell" as the GSM frequencies are licensed, even in those picocells that the carriers deploy in malls and sporting events.
T-Mobile's rumored new service will utilize a new class of mobile phones which are GSM and WiFi hybrids. While you are away from home the handset works like a normal GSM phone. When you get home the handset switches to WiFi and connects calls using a wireless VoIP gateway that you connect to your high-speed internet connection. T-Mobile will bundle the hybrig GSM+WiFi mobile phone, the WiFi VoIP gateway device, and the VoIP service. To the mobile phone user the only thing they notice is that their T-Mobile phone works at home and they can finally drop that PSTN line.
This is in response to the overwhelming T-Mobile customers who tried to use number portability to switch their home phone numbers to T-Mobile and found that their mobile phone didn't work in their homes. Most of T-Mobile's spectrum is 1900 MHz which doesn't penetrate well into buildings. At the same time, T-Mobile (and the other carriers) were spending billions to acquire space in the 800 MHz spectrum to try to improve the situation but someone had the bright idea for T-Mobile to offer all-in-one GSM+VoIP service for much less money than building out their mobile GSM networks which already work really well outdoors.
I think it's a brilliant plan and it's much cheaper than giving everyone GSM repeaters at $500-$1200 per unit just so their mobile phones will work in the house (but never the basement)... of course the hybrid GSM+WiFi phone *will* work in the basement. It's simply brilliant.
Let's see if they really roll this service out.
Kriston