Maybe this one: http://www.servalproject.org/ Mark Jordan On 09-Apr-13 17:37, Peter Loron wrote: > You may want to check this out: > > http://wush.net/trac/rangepublic/wiki > > At first glance, it looks like one could set up exactly what you're after= .. > > -Pete > > On Apr 9, 2013, at 5:21 AM, RussellMc wrote: > >> I'm interested in knowing what it would take at a minimum to enable >> GSM cellphone to cellphone comms among a limited number of phones in >> the absence of a traditional cell-site structure. ie add your own >> cell-site if necessary. >> >> That could be tightened up somewhat to say GSM 2G platform or better >> and could be just SMS, just voice, and ideally SMS and voice and data. >> >> Either all phones involved need to be capable of peer to peer >> communications, or a cell site / base station "cellphone tower" is >> needed. >> >> Has anyone here any experience in this area or can comment on the >> feasibility of using existing in-phone GSM hardware to meet this need. >> >> Assume regulatory issues are not of concern (even though in many cases >> they will be). >> A hypothetical example application might be a "flying cell site" that >> is used in look-down mode from high altitudes to provide search and >> rescue radio communications in rugged terrain allowing the use of >> cellphones by ground parties - which would otherwise be ineffective >> in cell-site-less valleys. If you can talk to the cellphone equipped >> hiker lying incapacitated with a broken leg, so much the better. (An >> extremely experienced wilderness veteran died some years ago in NZ >> after lying incapacitated for several weeks after a fall and not being >> found until too late. He should have been carrying a locator beacon, >> but with a flying cellsite a $25 phone would have saved his life. This >> example would easily support the basic "$1000 solution" below >> (although it would usually done for even more in that application) but >> some applications would benefit from lowest possible cost. >> >> >> Russell >> >> >> >> "Resources:" >> >> The minimum arrangement that I'm currently aware of is to implement a >> cell site (or "cellphone tower") using a SDR (Software defined radio) >> and a computer of some sort. Almost any linux box can be used and I've >> recently read of people doing it with a Raspberry Pi. >> >> The probably most accessible, but not necessarily the best, solution >> is the use of Open BTS (Open Base Transceiver Station) free software >> (refs below) with a suitable SDR (Software Defined Radio). >> >> The usual hardware starting point is the open source USRP1 - User >> Software Defined Radio transceiver. >> A version of this, the USRPB100 can be bought fully assembled from >> Ettus Research for $US650 retail. >> Various Ettus Research SDR's here >> https://www.ettus.com/product/category/USRP_Bus_Series >> Add an eg Raspberry Pi and probably a GPS timing source, basic power >> supply and aerial(s) and you have a workable base for around $US1000 >> (assuming your time is worth zilch). >> >> That's a good start , but cheaper still would be better. >> >> _____________________ >> >> Android SDR anyone :-) >> Agh: That opened up a whole new line of thought. eg Realtek RTL2832U >> DVB stick gives you an SDR control core for under $20. >> Looks like it could handle the receive size OK. >> Transmit? >> http://wiki.spench.net/wiki/RTL2832U >> http://www.hamradioscience.com/forum/discussion/88/setting-up-your-rtl28= 32u-dongle-for-sdr-use/p1 >> http://sdr.osmocom.org/trac/wiki/rtl-sdr >> http://dx.com/p/rtl2832u-r820t-mini-dvb-t-dab-fm-usb-digital-tv-dongle-b= lack-170541 >> >> __________________ >> >> Open BTS - Wikipedia http://en.wikipedia.org/wiki/OpenBTS >> >> OpenBTS (Open Base Transceiver Station) is a software-based GSM access >> point, allowing standard GSM-compatible mobile phones to be used as >> SIP endpoints in Voice over IP (VOIP) networks. OpenBTS is the first >> free software implementation of the lower three layers of the >> industry-standard GSM protocol stack. It is written in C++ and >> released as free software under the terms of version 3 of the GNU >> Affero General Public License (AGPL). >> >> Good GSM / Open BTS video 5m:34 >> http://www.youtube.com/watch?v=3DZoWKYJ1ATeE&feature=3Dplayer_embedded >> >> USRP Wikipedia >> http://en.wikipedia.org/wiki/Universal_Software_Radio_Peripheral >> >> USRP1 circuit diagram >> http://code.ettus.com/redmine/ettus/attachments/download/209/usrp1.pdf >> http://www.tcmaker.org/wiki/doku.php?id=3Dhamradio:ettus_researc= h_usrp1 >> >> USRP1 for sale $700 >> https://www.ettus.com/product/details/USRP-PKG >> >> The USRP1 is the original Universal Software Radio Peripheral=99 >> hardware (USRP) that provides entry-level RF processing capability. It >> is intended to provide software defined radio development capability >> for cost-sensitive users and applications. The architecture includes >> an Altera Cyclone FPGA, 64 MS/s dual ADC, 128 MS/s dual DAC and USB >> 2.0 connectivity to provide data to host processors. A modular design >> allows the USRP1 to operate from DC to 6 GHz. The USRP1 platform can >> support two complete RF daughterboards. This feature makes the USRP >> ideal for applications requiring high isolation between transmit and >> receive chains, or dual-band dual transmit/receive operation. The >> USRP1 can stream up to 8 MS/s to and from host applications, and users >> can implement custom functions in the FPGA fabric. >> _____________________________ >> >> 25C3 - Running your own GSM network. >> Excellent 44 minute video. >> http://www.youtube.com/watch?feature=3Dendscreen&NR=3D1&v=3De_9hPRF5fzA >> http://events.ccc.de/congress/2008/wiki/GSM/ >> >> Harald Welte This presentation will mark the first public release of a >> new GPL licensed Free Software project implementing the GSM fixed >> network, including the various minimal necessary functionality of BSC, >> MSC, HLR. It will introduce the respective standards and protocols, as >> well as a short demonstration of an actual phone call between two >> mobile phones registered to the base station. On the Ethernet/IP based >> Internet, we are used to Free Software and general-purpose hardware. >> The worlds second largest communications network GSM couldn=92t be any >> more different. Even though the protocols are standardized and >> publicly available at the ETSI, all implementations are highly-guarded >> proprietary secrets of a few major players in the industry. The >> hardware is even more closed, as there is not a single GSM subscriber >> or base station chipset with even the least bit of publicly known >> information. Nonetheless, in recent years there are a number of >> different projects working on driving a wedge of Openness into this >> world. You might have heard about other projects like the THC GSM >> sniffer project (pure wireshark-like functionality) and OpenBTS (a >> software defined radio based GSM base station interfacing with the >> Asterisk VOIP server). This presentation is about yet another new GSM >> related Open Source project. A project that follows the GSM specs more >> closely and actually aims at interoperability with existing equipment >> such as hardware BTS hooked up via S2M =85 >> >> _____________ >> >> Raspberry Pi Used To Replace A 30-Foot GSM Base Station And Create A >> Working Mobile Network >> Uses Open BTS and a Ettus SDR >> Excellent links in discussion >> http://techcrunch.com/2012/12/21/raspberry-pi-used-to-replace-a-30-foot-= gsm-base-station-and-create-a-working-mobile-network/ >> >> Open BTS source forge redirect page >> http://wush.net/trac/rangepublic >> This Trac is the home of the OpenBTS public release, a FOSS version >> of Range Network's self-contained SDR/GSM/VoIP stack. >> >> GNU Radio >> http://gnuradio.org/redmine/projects/gnuradio/wiki/OpenBTS >> >> Freeswitch >> http://en.wikipedia.org/wiki/FreeSWITCH >> FreeSWITCH is free and open source communications software for the >> creation of voice and messaging products. It is licensed under the >> Mozilla Public License (MPL), a free software license. Its core >> library, libfreeswitch, is capable of being embedded into other >> projects, as well as being used as a stand-alone application. >> >> Open BTS =96 superb You tube intro video for Open BTS >> >> Uses Ettus Research SPR USRP N210, ($US 1500 list) BUT could use eg >> USRPB100 at $US650 list. >> >> Software Radio / OpenBTS - The Well Tempered Hacker Ep 4 >> 16m 20s http://www.youtube.com/watch?v=3DpTb1_v8M6iA >> >> Range Networks >> http://www.rangenetworks.com/ >> >> -- >> http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive >> View/change your membership options at >> http://mailman.mit.edu/mailman/listinfo/piclist -- http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .