UL Sync Drops

[tsiz]

Hi All,

Does anybody know the trick to troubleshoot UL Sync drops? What should I be looking at to bring the drops due to UL sync down?

Thanks for sharing.

[cocoloco]

Due to bad RF conditions (bad Ec/Io mainly) there are UL Sync drops

[no_1'sfasterthanradiowave]

Basically due to unbalanced link - either due to noise rise in the UL or could be a hardware issue. The latter i have experienced with one cell , which is added in SHO with good quality&level but link is removed /5 secs after, but that would depend on timers set/ due to loss of synch /also configurable/. After change of faulty equipment everything was ok.
You could also increase the number of "out of synchs" and reduce the ones for regaining synchrinization but that would probably be a RNC parameter.
Also check for extensive hsupa traffic and try to offload the cell if that is the case.

[salamanda1969]

Assuming you are discussing a 3G issue:
If UL Sync fail experienced at call set up or handover, check if admission control was triggered, high PS/HSDPA traffic observed (both pointing to congestion in the cell) or some kind of UL interference.
Hope that helps.