[[bts-examples]] == OsmoNITB example configuration files The `openbsc/doc/examples/osmo-nitb` directory in the OpenBSC source tree contains a collection of example configuration files, sorted by BTS type. This chapter is illustrating some excerpts from those examples [[bts_example_bs11]] === Example configuration for OsmoNITB with one dual-TRX BS-11 .OsmoNITB with BS11, 2 TRX, no frequency hopping ==== ---- e1_input e1_line 0 driver misdn network network country code 1 mobile network code 1 short name OpenBSC long name OpenBSC timer t3101 10 timer t3113 60 bts 0 type bs11 <1> band GSM900 cell_identity 1 location_area_code 1 training_sequence_code 7 base_station_id_code 63 oml e1 line 0 timeslot 1 sub-slot full <2> oml e1 tei 25 <3> trx 0 arfcn 121 max_power_red 0 rsl e1 line 0 timeslot 1 sub-slot full <4> rsl e1 tei 1 <5> timeslot 0 phys_chan_config CCCH+SDCCH4 e1 line 0 timeslot 1 sub-slot full timeslot 1 phys_chan_config TCH/F e1 line 0 timeslot 2 sub-slot 1 <6> timeslot 2 phys_chan_config TCH/F e1 line 0 timeslot 2 sub-slot 2 timeslot 3 phys_chan_config TCH/F e1 line 0 timeslot 2 sub-slot 3 timeslot 4 phys_chan_config TCH/F e1 line 0 timeslot 3 sub-slot 0 timeslot 5 phys_chan_config TCH/F e1 line 0 timeslot 3 sub-slot 1 timeslot 6 phys_chan_config TCH/F e1 line 0 timeslot 3 sub-slot 2 timeslot 7 phys_chan_config TCH/F e1 line 0 timeslot 3 sub-slot 3 trx 1 arfcn 123 max_power_red 0 rsl e1 line 0 timeslot 1 sub-slot full <4> rsl e1 tei 2 <5> timeslot 0 phys_chan_config TCH/F e1 line 0 timeslot 4 sub-slot 0 <6> timeslot 1 phys_chan_config TCH/F e1 line 0 timeslot 4 sub-slot 1 timeslot 2 phys_chan_config TCH/F e1 line 0 timeslot 4 sub-slot 2 timeslot 3 phys_chan_config TCH/F e1 line 0 timeslot 4 sub-slot 3 timeslot 4 phys_chan_config TCH/F e1 line 0 timeslot 5 sub-slot 0 timeslot 5 phys_chan_config TCH/F e1 line 0 timeslot 5 sub-slot 1 timeslot 6 phys_chan_config TCH/F e1 line 0 timeslot 5 sub-slot 2 timeslot 7 phys_chan_config TCH/F e1 line 0 timeslot 5 sub-slot 3 ---- ==== <1> The BTS type must be set to __bs11__ <2> The OML E1 timeslot needs to be identical with what was on the BTS side using LMT. <3> The OML TEI value needs to be identical with what was configured on the BTS side using LMT. <4> The RSL E1 timeslot can be identical for all TRX. <5> The RSL TEI values __must__ be different if multiple TRX share one E1 signalling timeslot. <6> The TCH all need to be allocated one 16k sub-slot on the E1 [[bts_example_nbts]] === Example configuration for OsmoNITB with one single-TRX nanoBTS .OsmoNITB with one single-TRX nanoBTS ==== ---- e1_input e1_line 0 driver ipa <1> network network country code 1 mobile network code 1 short name OpenBSC long name OpenBSC auth policy closed location updating reject cause 13 encryption a5 0 neci 1 rrlp mode none mm info 1 handover 0 bts 0 type nanobts <2> band DCS1800 <3> cell_identity 0 location_area_code 1 training_sequence_code 7 base_station_id_code 63 ms max power 15 cell reselection hysteresis 4 rxlev access min 0 channel allocator ascending rach tx integer 9 rach max transmission 7 ip.access unit_id 1801 0 <4> oml ip.access stream_id 255 line 0 gprs mode none trx 0 rf_locked 0 arfcn 871 <5> nominal power 23 max_power_red 20 <6> rsl e1 tei 0 timeslot 0 phys_chan_config CCCH+SDCCH4 timeslot 1 phys_chan_config SDCCH8 timeslot 2 phys_chan_config TCH/F timeslot 3 phys_chan_config TCH/F timeslot 4 phys_chan_config TCH/F timeslot 5 phys_chan_config TCH/F timeslot 6 phys_chan_config TCH/F timeslot 7 phys_chan_config TCH/F ---- ==== <1> You have to configure one virtual E1 line with the IPA driver in order to use Abis/IP. One e1_line is sufficient for any number of A-bis/IP BTSs, there is no limit like in physical E1 lines. <2> The BTS type must be set using `type nanobts` <3> The GSM band must be set according to the BTS hardware. <4> The IPA Unit ID parameter must be set to what has been configured on the BTS side using the __BTS Manager__ or `ipaccess-config`. <5> The ARFCN of the BTS. <6> All known nanoBTS units have a nominal transmit power of 23 dBm. If a `max_power_red` of 20 (dB) is configured, the resulting output power at the BTS Tx port is 23 - 20 = 3 dBm. [NOTE] ==== The `nominal_power` setting does __not__ influence the transmitted power to the BTS! It is a setting by which the system administrator tells the BSC about the nominal output power of the BTS. The BSC uses this as basis for calculations. ==== [[bts_example_nbts_multi]] === Example configuration for OsmoNITB with multi-TRX nanoBTS .OsmoNITB configured for dual-TRX (stacked) nanoBTS ==== ---- e1_input e1_line 0 driver ipa network network country code 1 mobile network code 1 short name OpenBSC long name OpenBSC auth policy closed location updating reject cause 13 encryption a5 0 neci 1 rrlp mode none mm info 0 handover 0 bts 0 type nanobts band DCS1800 cell_identity 0 location_area_code 1 training_sequence_code 7 base_station_id_code 63 ms max power 15 cell reselection hysteresis 4 rxlev access min 0 channel allocator ascending rach tx integer 9 rach max transmission 7 ip.access unit_id 1800 0 <1> oml ip.access stream_id 255 line 0 gprs mode none trx 0 rf_locked 0 arfcn 871 nominal power 23 max_power_red 0 rsl e1 tei 0 timeslot 0 phys_chan_config CCCH+SDCCH4 timeslot 1 phys_chan_config SDCCH8 timeslot 2 phys_chan_config TCH/F timeslot 3 phys_chan_config TCH/F timeslot 4 phys_chan_config TCH/F timeslot 5 phys_chan_config TCH/F timeslot 6 phys_chan_config TCH/F timeslot 7 phys_chan_config TCH/F trx 1 rf_locked 0 arfcn 873 nominal power 23 max_power_red 0 rsl e1 tei 0 timeslot 0 phys_chan_config SDCCH8 timeslot 1 phys_chan_config TCH/F timeslot 2 phys_chan_config TCH/F timeslot 3 phys_chan_config TCH/F timeslot 4 phys_chan_config TCH/F timeslot 5 phys_chan_config TCH/F timeslot 6 phys_chan_config TCH/F timeslot 7 phys_chan_config TCH/F ---- ==== <1> In this example, the IPA Unit ID is specified as `1800 0`. Thus, the first nanoBTS unit (`trx 0`) needs to be configured to 1800/0/0 and the second nanoBTS unit (`trx 1`) needs to be configured to 1800/0/1. You can configure the BTS unit IDs using the `ipaccess-config` utility included in OpenBSC. [NOTE] ==== For building a multi-TRX setup, you also need to connect the TIB cables between the two nanoBTS units, as well as the coaxial/RF AUX cabling. ====