Cellular Network Infrastructure » Radio Access Network » OsmoPCU

MS can not establish TBF when it is moving away from BTS more than 2 km. This problem is causing by wrong TA adjustment requested by the PCU.

Below is the PCU traces to indicate that the PCU was wrongly set TA from 6 bits to 0 causing no TBF establishment for given MS.

<0001> ../../git/src/pcu_l1_if.cpp:360 RACH request received: sapi=1 qta=24, ra=119, fn=786612
<0007> ../../git/src/gprs_rlcmac_meas.cpp:186 DL Bandwitdh of IMSI=901555000002022 / TLLI=0xf6342bc3: 2 KBits/s
<0009> ../../git/src/gprs_bssgp_pcu.cpp:183 LLC [SGSN -> PCU] = TLLI: 0xc949121b IMSI: 901555000002021 len: 62
<0007> ../../git/src/gprs_rlcmac_meas.cpp:104 UL RSSI of TLLI=0xc949121b: -94 dBm
<0007> ../../git/src/gprs_rlcmac_meas.cpp:159 DL packet loss of IMSI=901555000002022 / TLLI=0xf6342bc3: 0%
<0002> ../../git/src/bts.cpp:1426 MS supports EGPRS multislot class 10.
<0001> ../../git/src/bts.cpp:1664 [PH-DATA] Updating TA 6 -> 0 on TRX = 0, TS = 7, FN = 786695
<0009> ../../git/src/tbf_ul.cpp:388 LLC [PCU -> SGSN] TBF len=62
<0009> ../../git/src/tbf_ul.cpp:388 LLC [PCU -> SGSN] TBF len=1510
<0009> ../../git/src/tbf_ul.cpp:388 LLC [PCU -> SGSN] TBF len=81