Project

General

Profile

Nokia Site family » History » Version 2

Anonymous, 02/19/2016 10:47 PM

1 1
OpenBSC is currently supporting the Site family of Nokia BTSes.
2
3
'''Things that work:'''
4
5
 - Nokia InSite and MetroSite units are proven to be working, UltraSite is probably working
6 2
 - Full Rate and Enhanced Full Rate voice calls (MO & MT)
7 1
 - SMS (MO & MT)
8
 - Cell reselection
9 2
 - Handover (please see this patch: [http://cgit.osmocom.org/openbsc/commit/?id=7d8fa3418ff6c589eba10e562da8b96995e19f7a] )
10 1
11
'''Handover:'''
12
13
The OpenBSC side of the handover logic works quiet well. But at the moment, there is a slight problem with the Nokia units. The handover decision is made correctly, the GSM phone is commanded to switch to the new channel on the new BTS, which the phone does. But despite the channel release is sent, the old channel never get released, and this leads to a Radio Link Failure.
14 2
15
Update: it seems that the root cause of the previous handover failure is that the InSite BTSes (probably others too) are not sending the channel release ACK to the BSC after the old channel release is requested by the BSC. Andreas Eversberg added a patch which overcomes this problem by implicating the missing ACK, so the BSC can continue and finish the handover process. This can be enbaled by adding the next line to the BTS part of the config file:
16
17
{{{
18
nokia_site no-local-rel-conf 1
19
}}}
20
21
This fix is tested on Nokia InSite and MetroSite units, all of them are performing handovers normally.
22
23
For more info, please see this patch: [http://cgit.osmocom.org/openbsc/commit/?id=7d8fa3418ff6c589eba10e562da8b96995e19f7a]
24 1
25
'''E1 cards:'''
26
27
The original Nokia support was written for HFC-E1 and mISDN. The Site can only be interfaced via traditional E1 lines (no IP ABIS support for these old units). It is also possible to use a DAHDI card to interface with the BTS. For this you have to use the following configuration in /etc/dahdi/system.conf:
28
29
{{{
30
span=1,0,0,ccs,hdb3,crc4	
31
bchan=1-31
32
}}}
33
34
Unlike in traditional E1 communication, we are using CCS signalling. For every signalling and traffic channel between the BTS and the BSC, we are using dedicated timeslots. Because of that, we are no longer need any shared signalling channel on the E1 line (e.g. D channel on timeslot 16.
35
36
'''Example config file for an 1800MHz Nokia InSite unit:'''
37
38
39
{{{
40
!
41
! OpenBSC configuration saved from vty
42
!   !
43
password foo
44
!
45
line vty
46
 no login
47
!
48
e1_input
49
 e1_line 0 driver dahdi
50
 # e1_line 0 port 0
51
 log file /root/900_nokia.log
52
 logging filter all 1
53
 logging color 1
54
 logging timestamp 1
55
 
56
network
57
 network country code 1
58
 mobile network code 1
59
 short name OpenBSC
60
 long name OpenBSC 
61
 neci 0
62
 rrlp mode none
63
 mm info 1
64
 handover 0
65
 handover window rxlev averaging 5
66
 handover window rxqual averaging 1
67
 handover window rxlev neighbor averaging 5
68
 handover power budget interval 6
69
 handover power budget hysteresis 3
70
 handover maximum distance 9999
71
 timer t3101 3
72
 timer t3103 5
73
 timer t3105 20
74
 timer t3107 10
75
 timer t3109 15
76
 timer t3111 2
77
 timer t3113 10
78
 timer t3115 0
79
 timer t3117 0
80
 timer t3119 0
81
 timer t3141 0
82
 timer t3122 10
83
84
 bts 0
85
  type nokia_site
86
  band GSM1800
87
  cell_identity 1
88
  location_area_code 1
89
  base_station_id_code 63
90
  training_sequence_code 7
91
  ms max power 12
92
  cell reselection hysteresis 4
93
  periodic location update 10
94
  nokia_site skip-reset 0
95
  
96
  oml e1 line 0 timeslot 8 sub-slot full
97
  oml e1 tei 1
98
  
99
  trx 0
100
   arfcn 885
101
   nominal power 18
102
   max_power_red 10
103
   rsl e1 line 0 timeslot 7 sub-slot full
104
   rsl e1 tei 1
105
106
107
    timeslot 0
108
     phys_chan_config CCCH+SDCCH4
109
     e1 line 0 timeslot 5 sub-slot 0
110
111
    timeslot 1
112
     phys_chan_config SDCCH8
113
     e1 line 0 timeslot 5 sub-slot 1
114
115
    timeslot 2
116
     phys_chan_config TCH/F
117
     e1 line 0 timeslot 5 sub-slot 2
118
119
    timeslot 3
120
     phys_chan_config TCH/F
121
     e1 line 0 timeslot 5 sub-slot 3
122
123
    timeslot 4
124
     phys_chan_config TCH/F
125
     e1 line 0 timeslot 6 sub-slot 0
126
127
    timeslot 5
128
     phys_chan_config TCH/F
129
     e1 line 0 timeslot 6 sub-slot 1
130
131
    timeslot 6
132
     phys_chan_config TCH/F
133
     e1 line 0 timeslot 6 sub-slot 2
134
135
    timeslot 7
136
     phys_chan_config TCH/F
137
     e1 line 0 timeslot 6 sub-slot 3
138
139
}}}
140
141
'''LMP cable pinout for InSite units:'''
142
143
'''LMP cable pinout for MetroSite units:'''
144
145
'''Tips and tricks for Site family and OpenBSC:'''
Add picture from clipboard (Maximum size: 48.8 MB)