Project

General

Profile

Transceiver » History » Version 1

steve-m, 02/19/2016 10:49 PM

1 1 steve-m
= Transceiver =
2
3
The following how-to will guide you through the steps needed for using an OsmocomBB-compatible phone as transceiver for OpenBTS.
4
5
=== Prerequisites ===
6
7
First of all, make sure you have the '''[wiki:PreliminaryRequirements Preliminary Requirements]'''. Also, you '''need to have a [wiki:GettingStarted working setup]''' of OsmocomBB.
8
9
To get started with your phone-as-BTS setup, follow the following steps:
10
11
=== Dependencies ===
12
13
The transceiver needs libosmodsp as a dependency:
14
15
{{{
16
#!sh
17
git clone git://git.osmocom.org/libosmo-dsp.git
18
}}}
19
20
To compile and install it:
21
22
{{{
23
#!sh
24
cd libosmo-dsp/
25
autoreconf -i
26
./configure
27
make
28
sudo make install
29
cd ..
30
}}}
31
32
=== Building OsmocomBB ===
33
34
In the OsmocomBB-tree, switch to the sylvain/testing branch:
35
{{{
36
#!sh
37
git checkout sylvain/testing
38
}}}
39
40
After doing that, build the source:
41
42
{{{
43
#!sh
44
make HOST_layer23_CONFARGS=--enable-transceiver
45
}}}
46
47
=== Building OpenBTS ===
48
49
Follow this [http://wush.net/trac/rangepublic/wiki/BuildInstallRun excellent how-to] in the Range Networks Public wiki on building OpenBTS.
50
51
Once you have OpenBTS up and running, you need to change the following configuration parameters in the database (/etc/OpenBTS/OpenBTS.db):
52
53
{{{
54
Control.GSMTAP.TargetIP = 127.0.0.1
55
GSM.Radio.NeedBSIC = 1
56
GSM.Radio.Band = 1800
57
GSM.CellSelection.Neighbors =           (set to empty string)
58
GSM.RACH.MaxRetrans = 3
59
GSM.RACH.TxInteger = 8
60
GSM.Radio.C0 = <your ARFCN (see note)>
61
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)
62
}}}
63
64
'''Warning:''' Only set GSM.Radio.C0 to an ARFCN you have a '''valid license''' for.
65
66
=== Booting the phone ===
67
68
Use osmocon to execute the '''trx''' app on the phone (trx.compalram/highram.bin).
69
70
=== Starting OpenBTS ===
71
72
In the folder where the OpenBTS executable resides, create a script with the filename '''transceiver''' with the following content and make it executable:
73
74
{{{
75
#!sh
76
#!/bin/bash
77
exec <your path to osmocom-bb>/src/host/layer23/src/transceiver/transceiver 1
78
}}}
79
80
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).
81
82
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.
Add picture from clipboard (Maximum size: 48.8 MB)