
LimeSDR GSM Base Station Demo - ChuckMcM
https://www.crowdsupply.com/lime-micro/limesdr/updates/gsm?utm_source=LimeSDR+supporters&utm_campaign=ea161a4144-Project_Update_Lime_GSM_6_18_2016&utm_medium=email&utm_term=0_1e5a81cd57-ea161a4144-112322449
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Ebrahim24
LimeSDR board is open source and the complete database is published on:
[https://github.com/myriadrf/LimeSDR-USB](https://github.com/myriadrf/LimeSDR-
USB)

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ChuckMcM
This is why I hope this gets funded, I would really like to understand the GSM
protocols as deeply as these folks do.

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teamster94
This group of people are not the developers of the open-source GSM basestation
stack they demod, funding them does not contribute to the OpenBTS. Fairwaves
built a business trying to commercialize the readily available OpenBTS
software stack, which was developed by Range Networks. Range split and the
original author of OpenBTS, is the project maintainer behind YateBTS, which is
a totally revamped version of OpenBTS with support in the works for LTE. So if
you care about GSM, and LTE basestations go directly to the source
[http://yatebts.com](http://yatebts.com)

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ChuckMcM
Thanks for the links, my concern is for having affordable hardware to run the
stack on.

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teamster94
The whole setup to run something like this already runs in the high thousands.
If you plan on doing anything worthwhile (legally) you will be spending nearly
$5,000 on a benchtop RF cage. If you plan on needing amplifiers to get more
than 10 feet of range you will be spending $2,000 on an amplifier. There are
no shortcuts in RF, operating an illegal basestation can very easily affect
E911 service and put you in jail for a very long time if your basestation
stops someone from receiving emergency services.

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dogma1138
I don't want to go into too many details for obvious reasons but you really do
not need to spend a 2000$ on an amplifier to get more than 10 feet of range if
you are building say a DIY IMSI catcher.

Just suffice to say are over the counter (if you are willing to order from
china, or heck Dealextreme) cell blockers and boosters that cost <200$ that
can block cell reception over a much much greater area than a 10 ft radius.

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walrus01
Just a warning: If you mess around with ANY of this and:

a) don't have specific written permission from the FCC or Industry Canada (or
your local spectrum regulator)

and/or

b) Don't do it in a good quality faraday cage

You deserve an FCC party van...

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tostitos1979
Can you change the transmission bands to the ISM ones or is it fixed to GSM
bands? For a tinkers setup, the frequency shouldn't matter since you may not
care about performance? Asking out of curiosity.

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walrus01
I suppose you could, on the SDR, but then no standard feature phone or
smartphone would talk to it.

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SSLy
Is there any open source project that codes the "core" network elements of
mobile neworks? BTS are just tip of the iceberg.

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chemeris
Yes. Osmocom/OpenBSC actually started as an open-source "network in a box"
which implements all critical GSM network elements in a single executable. It
greatly expanded since then - check out a list of projects there. As I
mentioned below, more companies are joining Osmocom and there will be
hopefully more work on the core network side. Other open-source projects
targeting core network elements are
[http://www.mobicents.org/](http://www.mobicents.org/) and
[http://www.projectclearwater.org/](http://www.projectclearwater.org/) (IMS).

