Nokia InSite handover

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Sipos Csaba dchardware at gmail.com
Mon Jul 22 21:51:10 UTC 2013


Hi Harald,

> this check should be conditional on using a nanobts/sysmobts, and not be
> present for E1 based bts's.

I just removed that check from the code and now it is possible to
enable the HO functions without the RTP Proxy.

> You should enable debugging logging of the handover code and see what
> kind of messages you get.  'logging enable' 'lgging filter all 1' and
> 'logging level ho debug' should do the trick.

I did as you said, the result is interesting, I just paste the
relevant log parts, the full dump (logging all debug) is attached.

So I wanted to do inter-BTS handover (two Nokia InSite units, one
GSM900 and one GSM1800), neighbors list configured. Two phones calling
each other, each one is camped on different cell. The one that is
camped on the GSM1800 unit tries to handover to the GSM900 unit. Here
is what happens:

<000c> handover_decision.c:203 (bts=0,trx=0,ts=2): Cell on ARFCN 123 is better:
<000c> handover_logic.c:96 (old_lchan on BTS 0, new BTS 1) Starting handover
<0004> abis_rsl.c:1165 (bts=1,trx=0,ts=2,ss=0) CHANNEL ACTIVATE ACK
<000c> handover_logic.c:204 handover activate ack, send HO Command
<0004> abis_rsl.c:1138 (bts=1,trx=0,ts=2,ss=0) HANDOVER DETECT access delay = 0
<0000> abis_rsl.c:1621 (bts=1,trx=0,ts=2,ss=0) SAPI=0 ESTABLISH INDICATION
<0000> abis_rsl.c:1621 (bts=1,trx=0,ts=2,ss=0) SAPI=0 DATA INDICATION
<0003> bsc_api.c:515 HANDOVER COMPLETE cause = Normal event
<000c> handover_logic.c:261 Subscriber 244153333330126 HO from BTS 0->1 on ARFCN 885->123
<0000> chan_alloc.c:405 (bts=0,trx=0,ts=2,ss=0) starting release sequence
<0000> abis_rsl.c:891 (bts=0,trx=0,ts=2,ss=0) RSL RLL RELEASE REQ (link_id=0x00, reason=1)

<0004> abis_rsl.c:1069 (bts=0,trx=0,ts=2,ss=0): MEAS RES for inactive channel
<0004> abis_rsl.c:1069 (bts=0,trx=0,ts=2,ss=0): MEAS RES for inactive channel
<0004> abis_rsl.c:1069 (bts=0,trx=0,ts=2,ss=0): MEAS RES for inactive channel
..
..
<0004> abis_rsl.c:1069 (bts=0,trx=0,ts=2,ss=0): MEAS RES for inactive channel
<0004> abis_rsl.c:1069 (bts=0,trx=0,ts=2,ss=0): MEAS RES for inactive channel
<0004> abis_rsl.c:1069 (bts=0,trx=0,ts=2,ss=0): MEAS RES for inactive channel

<0004> abis_rsl.c:988 (bts=0,trx=0,ts=2,ss=0) CONNECTION FAIL: RELEASING CAUSE=0x01(Radio Link Failure)
<0004> abis_rsl.c:679 (bts=0,trx=0,ts=2,ss=0) RF Channel Release CMD due error 1
<0004> abis_rsl.c:633 (bts=0,trx=0,ts=2,ss=0) DEACTivate SACCH CMD
<0000> abis_rsl.c:891 (bts=0,trx=0,ts=2,ss=0) RSL RLL RELEASE REQ (link_id=0x40, reason=1)
<0004> abis_rsl.c:1069 (bts=0,trx=0,ts=2,ss=0): MEAS RES for inactive channel
<0004> abis_rsl.c:731 (bts=0,trx=0,ts=2,ss=0) RF CHANNEL RELEASE ACK
<001a> trau_frame.c:196 unimplemented TRAU Frame Type 0x06
<-- a lot of "unimplemented TRAU Frame Type 0x06" -->
<001a> trau_frame.c:275 unimplemented TRAU Frame Type 0x06
<0004> abis_rsl.c:988 (bts=0,trx=0,ts=3,ss=0) CONNECTION FAIL: RELEASING CAUSE=0x28(unknown 0x28)
<0004> abis_rsl.c:679 (bts=0,trx=0,ts=3,ss=0) RF Channel Release CMD due error 1
<0004> abis_rsl.c:633 (bts=0,trx=0,ts=3,ss=0) DEACTivate SACCH CMD
<0000> abis_rsl.c:891 (bts=0,trx=0,ts=3,ss=0) RSL RLL RELEASE REQ (link_id=0x40, reason=1)

<0004> abis_rsl.c:731 (bts=0,trx=0,ts=3,ss=0) RF CHANNEL RELEASE ACK
<0001> gsm_04_08.c:1265 (bts 0 trx 0 ts 3 ti 0 sub 12346) Sending 'MNCC_REL_IND' to MNCC.
<0006> mncc_builtin.c:348 (call 1) Received message MNCC_REL_IND
<0006> mncc_builtin.c:257 (call 1) Releasing remote with cause 47
<0006> mncc_builtin.c:52 (call 1) Call removed.
<0006> gsm_04_08.c:2877 receive message MNCC_REL_REQ
<0001> gsm_04_08.c:3063 (bts 0 trx 0 ts 2 ti 08 sub 12345) Received 'MNCC_REL_REQ' from MNCC in state 10 (ACTIVE)
<0001> gsm_04_08.c:1739 starting timer T308 with 10 seconds
<0001> gsm_04_08.c:1204 new state ACTIVE -> RELEASE_REQ
<0001> gsm_04_08.c:113 (bts 1 trx 0 ts 2 ti 80) Sending 'RELEASE' to MS.
<0001> gsm_04_08.c:1204 new state ACTIVE -> NULL

<0000> abis_rsl.c:1621 (bts=1,trx=0,ts=2,ss=0) SAPI=0 DATA INDICATION
<0001> gsm_04_08.c:3156 (bts 0 trx 0 ts 2 ti 8 sub 12345) Received 'RELEASE_COMPL' from MS in state 19 (RELEASE_REQ)
<0001> gsm_04_08.c:1245 stopping pending timer T308
<0001> gsm_04_08.c:1265 (bts 1 trx 0 ts 2 ti 8 sub 12345) Sending 'MNCC_REL_CNF' to MNCC.
<0006> mncc_builtin.c:348 (call 80000001) Received message MNCC_REL_CNF
<0006> mncc_builtin.c:52 (call 80000001) Call removed.
<0001> gsm_04_08.c:1204 new state RELEASE_REQ -> NULL
<0000> chan_alloc.c:405 (bts=1,trx=0,ts=2,ss=0) starting release sequence
<0003> gsm_04_08_utils.c:231 Sending Channel Release: Chan: Number: 0 Type: 2
<0004> abis_rsl.c:633 (bts=1,trx=0,ts=2,ss=0) DEACTivate SACCH CMD
<0000> abis_rsl.c:1621 (bts=1,trx=0,ts=2,ss=0) SAPI=0 RELEASE INDICATION
<0004> abis_rsl.c:679 (bts=1,trx=0,ts=2,ss=0) RF Channel Release CMD due error 0
<0004> abis_rsl.c:731 (bts=1,trx=0,ts=2,ss=0) RF CHANNEL RELEASE ACK
<0004> abis_rsl.c:648 (bts=0,trx=0,ts=2,ss=0) is back in operation.
<0004> abis_rsl.c:648 (bts=0,trx=0,ts=3,ss=0) is back in operation.

In the moment when the phone handed over to the new serving BTS, the
voice is completely noisy, and after a few seconds both phones got
disconnected.

This is the same with both directions, and "show statistics" shows
that these handovers were all successful.

My config:

 handover 1
 handover window rxlev averaging 10
 handover window rxqual averaging 1
 handover window rxlev neighbor averaging 10
 handover power budget interval 6
 handover power budget hysteresis 3
 # handover maximum distance 9999
 timer t3101 10
 timer t3103 6
 timer t3105 2
 timer t3107 0
 timer t3109 4
 timer t3111 9
 timer t3113 60
 timer t3115 0
 timer t3117 0
 timer t3119 0
 timer t3141 0
 timer t3122 5

bts 0
       cell reselection hysteresis 4
       periodic location update 6
       neighbor-list mode manual
       neighbor-list add arfcn 123
       rxlev access min 22
bts 1
     cell reselection hysteresis 4
     periodic location update 6
     neighbor-list mode manual
     neighbor-list add arfcn 885
     nokia_site skip-reset 1
     rxlev access min 22

For OML and RSL I am using D channels, the traffic channels are B
channels in the DAHDI config file.

If someone has an idea what to do or try, it will be appreciated.

Thanks,
Csaba
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