can_Eck avn0003 CPICH_Scan_Eck CPICH_Scan_Eck Monitore -15.0 -106 0 CPICH_Scan_Ecl -21.0 112.0 CPICH_Scan_Ec -21.0 -112.0 avn0143b1 avn0144 M0068b1 CPICH_Scan_RSCP_ -25.0 -116.0 mv0190b1 CPICH_Scan_SC_So Ec/lo 2 Miles Statistics Data avn013 Other -2'41'27 04" Lon. 51°26'34.46" avn0107b avn0137b1 UMTS Cal Inform Vendor Specific Replay SuperStream001 N Nemo SuperStream001 TxPower Event Data Called 797 7399001 NemoEvent NemoEvent Calling NemoEvent Call ID NemoEvent_ NemoEvent Outgoing Cell Sclup ARI FCN 10011 NemoEvent 09:04:039 Fevorites Analyzer Ready Figure 2.95 Drop call analysis Symptoms: low Ec/10 in the UE and Ec/10 on the scanner; low RSCP in the UE and in the scanner; UE transmitting on the maximum TX power. Problem: poor coverage area. The Ec/10 handover threshold should first trigger an interfrequency han- dover; if no 3G neighbour is detected the intersystem handover is triggered. If the UE is still not able to detect any neighbours the radio link to the serving cell is failing. The power control cannot improve signal quality due to maximum UE/NodeB transmission power already used. The call drops. Symptoms: low Ec/10 in the UE and Ec/10 on the scanner; normal RSCP in the UE and in the scan- ner; several scrambling codes with similar Ec/10 are detected in the active and monitored sets; high RSSI. Problem: pilot pollution area. Too many cells are covering the same area with equal RSCP. With many scrambling codes present the RSSI that measures the total received power has a high value. The RSCP should be within -15 dBm of the RSSI. If the overall interference level is high the requirement for the serving signal increases and thus even a normal RSCP does not provide the required Ec/10. Analysing Poor Performing Cells The poor coverage area and pilot pollution area problems described in the drop call analysis section also apply when analysing poor performing cells. The calls have not necessarily been dropping, but there could be performance problems on the cell level that could cause calls to drop, but this w