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thuti
2010-12-29, 02:47 AM
Hi everybody,

I have problem in analyzing dropcall in 3G. Now, if you see picture, the received signal (RSCP) is -70 dBm; however, logfile appear suddenly signal GSM (BSIC 2-7, RxLev -69). It makes to drop call. I don't know why this problem appear. Plz, help me to explain this problem. Thanks a lot :confused:

http://ca2.upanh.com/18.636.23074722.dQ0/analyse.png

http://upload69.net/images/72915817043489041709.pnghttp://www.finetopix.com/attachment.php?attachmentid=12968&stc=1&d=1293558337
http://upload69.net/images/72915817043489041709.png

icebreaker05
2010-12-29, 03:08 AM
Hi,

Could you please check the neighbor relation. From what I can see, there is one Detected Neighbor(DN) appearing on the WCDMA neighbor relation tab of TEMS which has good Ec/No. Try to define it or if in case its not one of the close neighbors, try to downtilt it. Then do again the drivetest.

BR,

tremalnike
2010-12-29, 03:21 AM
icebreaker05 outstrip me :)

Missing neighbor SC48 and pilot pollution in this area .

thuti
2010-12-29, 03:41 AM
Thanks, however I don't understand why appear 2G signal GSM????? Does it make interferences and drop-call?

In this case, why does appear drop-call? (This case appear GSM signal, too)

http://ca8.upanh.com/18.637.23075531.uiQ0/analyse2.png

Additionally, I want to ask you about " Drop type: Abnormal RRC Connection Release" (why?)

And, "e1c, a non-active primary CPICH becomes better than an active primary CPICH"???:confused:

http://ca9.upanh.com/18.637.23075532.sAR0/analyse3.png

icebreaker05
2010-12-29, 03:53 AM
Thanks, however I don't understand why appear 2G signal GSM????? Does it make interferences and drop-call?

In this case, why does appear drop-call? (This case appear GSM signal, too)

http://ca8.upanh.com/18.637.23075531.uiQ0/analyse2.png

Additionally, I want to ask you about " Drop type: Abnormal RRC Connection Release" (why?)

And, "e1c, a non-active primary CPICH becomes better than an active primary CPICH"???:confused:

http://ca9.upanh.com/18.637.23075532.sAR0/analyse3.png


Your question is already answered by the layer 3 message. There is still a non active CPICH(ec/no) better than you serving(AS) CPICH ec/no. In this case your neighbor is not defined therefore forcing the connection to be released. The UE can't make the undefined neighbor as part of your Active set. Clear case of pilot pollution..

thuti
2010-12-29, 04:49 AM
Your question is already answered by the layer 3 message. There is still a non active CPICH(ec/no) better than you serving(AS) CPICH ec/no. In this case your neighbor is not defined therefore forcing the connection to be released. The UE can't make the undefined neighbor as part of your Active set. Clear case of pilot pollution..

OK, I accept with your reply about pilot and missing neighbor. However, I want to ask you about the signal of GSM (2G) appeared in area. How to explain? :L

a19997104
2010-12-29, 02:24 PM
in some moment the event 2D was trigered (start searching for GSM neighbours) because of low EcIo (due to pillot pollution or missing neighbour), in the L3 messages you can see that the UE is reporting also 2F events, so its measuring GSM also

regards

Frank Mamani - Wireless Communications - Wireless Communications - Science (http://www.allexperts.com/ep/2435-119860/Wireless-Communications/Frank-Mamani.htm)

sala70vic
2010-12-29, 04:58 PM
Hi everybody,

I have problem in analyzing dropcall in 3G. Now, if you see picture, the received signal (RSCP) is -70 dBm; however, logfile appear suddenly signal GSM (BSIC 2-7, RxLev -69). It makes to drop call. I don't know why this problem appear. Plz, help me to explain this problem. Thanks a lot :confused:

http://ca2.upanh.com/18.636.23074722.dQ0/analyse.png

http://upload69.net/images/72915817043489041709.pnghttp://www.finetopix.com/attachment.php?attachmentid=12968&stc=1&d=1293558337
http://upload69.net/images/72915817043489041709.png

Hi,
In addition to the below analysis by the forume members:
1- What is the setting of Event 1B relative threshold and its time to trigger?
2- Is there any CIO offset with cells SC425 & SC314?
regards,

zhanglw268
2010-12-29, 08:25 PM
In the events Window, the compressed Mode was started before RRC was fully released, so it is possible that TEMS was measuring GSM at that time, you can replay the log file to see whether this is true.

OK, I accept with your reply about pilot and missing neighbor. However, I want to ask you about the signal of GSM (2G) appeared in area. How to explain? :L