Thread: [Idea] Walkie Talkie with FM Trans/Receiver (Maybe stupid, but just an idea)
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Wikiwide is offline Wikiwide
2010-11-27 , 04:28
Posts: 2,006 | Thanked: 3,351 times | Joined on Jun 2010 @ N900: Battery low. N950: torx 4 re-used once and fine; SIM port torn apart
#29
Originally Posted by TiagoTiago View Post
A while ago, i think it was on the IRC channel, there was someone talking about how they had used a SIP server (i think it was running on a N900, though there might have been a laptop and/or a WiFi router involved) to call other SIP+WiFi enabled devices, i think this was done while camping, creating their own little SIP network while they were there.
There is Asterisk PBX workable on N900 or a laptop. What does it do? It seems that it allows attached telephones to call to each other.

When a phone connects to Asterisk server, using login and password, Asterisk finds corresponding number in conf file, and then any phone attached to Asterisk can dial this phone using this number.

As N900 supports SIP calling out-of-the-box, the main question would be how difficult it is to get SIP client and Asterisk server talking with each other on the same machine. Though Wi-Fi should be able to be used by several programs at the same time in all directions.

https://wiki.asterisk.org/wiki/displ...p+Applications

Asterisk can also connect to cellular network. But it seems that it isn't working like BTS, though I'm not sure.

Originally Posted by theonelaw View Post
I have been following your link to OpenBTS
and as I read it the phone radio firmware is probably locked
into needing a BTS to camp on.

The open BTS way sounds completely workable though.

As the radio firmware is probably one of Nokia's darkest secrets
it may be impossible to find a way to actually drive the radio
to to call/sms another radio without going through a BTS.
Just guessing - never really studied GSM before this.
Very well, can an open BTS be compiled on N900?
It should be possible, because MeeGo should be completely open, and MeeGo works on N900.
When BTS works on N900, can N900 use it for transmitting its own SMS aka through SMS center? It's most likely impossible because one antenna would have to transmit and receive at the same time. Or it might be possible by telling BTS to use external headphones antenna.
Is SMS centre also used for phone calls? It would simplify switching N900 to an alternative BTS.
Besides, if certain frequency supported by N900 isn't used by telephony in your region, but isn't used by any other service either, then BTS would have much less interference with existing towers.

Just throwing in some ideas...

Hoping some GSM guru will come and tell whether it's implementable and possibly code a basic program.
Last edited by Wikiwide; 2010-11-27 at 05:59.
 

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