Project

General

Profile

Actions

Transceiver » History » Revision 1

Revision 1/5 | Next »
steve-m, 02/19/2016 10:49 PM


= Transceiver =

The following how-to will guide you through the steps needed for using an OsmocomBB-compatible phone as transceiver for OpenBTS.

=== Prerequisites ===

First of all, make sure you have the '''[wiki:PreliminaryRequirements Preliminary Requirements]'''. Also, you '''need to have a [wiki:GettingStarted working setup]''' of OsmocomBB.

To get started with your phone-as-BTS setup, follow the following steps:

=== Dependencies ===

The transceiver needs libosmodsp as a dependency:

{{{
#!sh
git clone git://git.osmocom.org/libosmo-dsp.git
}}}

To compile and install it:

{{{
#!sh
cd libosmo-dsp/
autoreconf -i
./configure
make
sudo make install
cd ..
}}}

=== Building OsmocomBB ===

In the OsmocomBB-tree, switch to the sylvain/testing branch: {{{
#!sh
git checkout sylvain/testing
}}}

After doing that, build the source:

{{{
#!sh
make HOST_layer23_CONFARGS=--enable-transceiver
}}}

=== Building OpenBTS ===

Follow this [http://wush.net/trac/rangepublic/wiki/BuildInstallRun excellent how-to] in the Range Networks Public wiki on building OpenBTS.

Once you have OpenBTS up and running, you need to change the following configuration parameters in the database (/etc/OpenBTS/OpenBTS.db):

{{{
Control.GSMTAP.TargetIP = 127.0.0.1
GSM.Radio.NeedBSIC = 1
GSM.Radio.Band = 1800
GSM.CellSelection.Neighbors = (set to empty string)
GSM.RACH.MaxRetrans = 3
GSM.RACH.TxInteger = 8
GSM.Radio.C0 = <your ARFCN (see note)>
Control.LUR.OpenRegistration = ^26242.*$ (note: in this example only IMSIs with MCC 262 and the MNC 42 will be allowed to register to the network, change that accordingly)
}}}

'''Warning:''' Only set GSM.Radio.C0 to an ARFCN you have a '''valid license''' for.

=== Booting the phone ===

Use osmocon to execute the '''trx''' app on the phone (trx.compalram/highram.bin).

=== Starting OpenBTS ===

In the folder where the OpenBTS executable resides, create a script with the filename '''transceiver''' with the following content and make it executable:

{{{
#!sh
#!/bin/bash
exec <your path to osmocom-bb>/src/host/layer23/src/transceiver/transceiver 1
}}}

Whereas 1 needs to be replaced with the ARFCN of the reference cell you want to use for synchronization (find a strong one with the '''rssi'''-app for example).

You now can start up OpenBTS and should hopefully see the BTS by performing a manual network search with your phone. Monitor the output of osmocon and the transceiver/OpenBTS to see if all goes well. If anything should fail, reboot the phone and start over.

Files (0)

Updated by steve-m about 8 years ago · 1 revisions

Add picture from clipboard (Maximum size: 48.8 MB)