Low signal strengh

[chonejin]

I have problems with a lot of drop by low signal strengh (in uplink) somebody have information about that ?


Thank you!

[rffreeconsult]

Check the output Power and downtilt to see if they are correct with the design...Installation can be sloppy and affect the link budget. Sweep and check the cables for any installation issues. Check if there are LNA (Low noise amplifiers) and if they are correctly installed. The question is too vague and general to have a a pinpoint solution. but the recommendations are enough to start troubleshooting,.

[pitoyco]

The questions a bit vague. But try checking timing advance if it's 2G or propagation delay if it's 3G. Check whether the cell is overshooting. If problem cell is at urban setting, poor indoor coverage may also be considered.

[radenmohawk]

1. check the coverage (based on TA) from MRR. Hilly area or facing to sea can generate CDR due to signal strength
2. check parameters, neighbor audit.
3. check alarm/HW faulty (VSWR, antenna system, DRU/CDU faulty), try block-deblock DRU to find DRU problem.
4. check antenna tilting/azimuth (suspect to difference of tilting/azimuth if use more than one antenna in one sector.)

[otimes]

thank you,radenmohawk

[otimes]

it may also be the imbalance between the UL and DL.

[rajmeena06]

Hi all,

How we can identify that is call drop is happening due to uplink level only (System huawei 2G)..
what Rx level ul & dl & quality value we should keep in mind while saying drop is happening due to Poor UL Level.Pl discuss

[Ericsson_RND]

As mentioned by our experts, Drive test will give indication, also check the installation especally if this site is new

[stilloboy]

Hi all,How we can identify that is call drop is happening due to uplink level only (System huawei 2G)..what Rx level ul & dl & quality value we should keep in mind while saying drop is happening due to Poor UL Level.Pl discuss

Usually when the downlink coverage is good and the path imbalance is greater than about 25dB. The path imbalance may result due to hardware issues in uplink path or could be due to the fact that the serving cell, before the drop, was overshooting. Of course, the possibility that there was interference on the serving cell will have to be removed before you can begin to suspect high downlink-uplink path difference (or path imbalance).

[danikd]

Prior to see for problem in HW, please, check the parameters set, which is responsible for dropped call classification. It can be wrong settings for those parameters and you are getting misleading drop cause. Parameter called LOWSSDL and LOWSSUL on BSC level.
Please, put the correct values for both of them...the correct values should be validated with your link budget and equipment configuration. The normal LOWSSUL should be 2-4dB above BTS sensitivity level (-110dBm) and LOWSSDL should be 2-4dB above MS sensitivity level (-104dBm). Please, not that LOWSSUL should be ~6dB lower than LOWSSDL (link budget values shift). This will help you classify correctly your drops. With wrong settings of LOWSSDL and LOWSSUL you my noy recognize the real drop cause, since LOWSS reason is the first priority condition that BSC checks for drop classification, then BAD Quality and then TA.
Once you get correct classification, then start to look for the drops reason