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rishi
2011-11-16, 03:40 PM
Dear Expert,

Can anyone tell what exactly is UL Bad Quality and what are the causes for UL BAd quality????

How do we measure C/I at a given pooint if a two signals are meeting at a desired location with Rx level -70dbm and -80 dbm and what would be its value????

Please reply me if anyone knows about this....

Piscean21
2011-11-16, 06:44 PM
Dear
Ul Bad quality may be due to weak uplink. You need to sort out the TRX in this case on which bad quality is being observed.

Regarding your second question DT softwares e.g Tems Investigation can be used.

rishi
2011-11-16, 08:44 PM
I know about tems and its value but if i want to calculate its exact value by means.of any formula what can be its formula can anyone know its formula

tharinduwije
2011-11-16, 09:00 PM
Did you check the ICm band levels of the current TCH frequencies? May be due to an external interference

RF engineer
2011-11-17, 01:36 AM
Dear Expert,

Can anyone tell what exactly is UL Bad Quality and what are the causes for UL BAd quality????

How do we measure C/I at a given pooint if a two signals are meeting at a desired location with Rx level -70dbm and -80 dbm and what would be its value????

Please reply me if anyone knows about this....


Dear

Uplink Quality could be interference when u have all MS working at maximum power which in this case need to optimize power control to handle near far effect or it may be you have external interference . and C/I for the above level will be 10 ( -70+80) .

BR

Fado
2012-05-16, 01:49 AM
Dear Expert,

Can anyone tell what exactly is UL Bad Quality and what are the causes for UL BAd quality????

How do we measure C/I at a given pooint if a two signals are meeting at a desired location with Rx level -70dbm and -80 dbm and what would be its value????

Please reply me if anyone knows about this.... UL bad quality means BTS can't hear the MS well..it might be due to interference on uplink which is either caused by bad freq plan or too many MS trying to talk to BTS with full power -shouting ;) - , also it might be due to bad RX antenna of BTS,bad TMA,LNB/A,faulty TRX that is anything between MS to BTS path... C/I is easy as it is in db (that is logarithmic) you should subtract it (-80-(-70)=-10dbm..cheers!

huawrx
2012-05-16, 09:06 PM
I hope that this could help you...
"
Interference is divided into uplink interference and downlink interference. You can analyze the uplink interference according to the number of interference bands into which the idle TCHs drop. It is normal that the idle TCHs drop into interference band 1 and interference band 2. For the network with aggressive frequency reuse, it is acceptable that the idle TCHs drop into interference band 3. Here the frequency hopping, PBGT handover and coverage control must be considered. If the idle TCHs drop into interference band 4 or above, you should carefully check the interference. Generally, the interference within the network increases with the traffic volume. The increase of the Rxqual class can be seen through the Rxqual measurement task and Rxlev measurement task. The poor handover ratio can be seen arising through inter-cell handover performance measurement. In addition, the handover re-establishment failures will result in more handover failures."