I have come across with similar case in Nokia.
voice CSSR (Phase 3 CSSR) is degrading in sec 2.
Multiple alarms like, BTS with no transactions, Object Administrative state changed BCCH missing, BTS O&M Link Failure, Configuration of BCF failed are pegging on site. SDCCH Phase 3 drops have been increased from same date on sec 2. No change in traffic pattern observed. No TCH/SDCCH Blocking observed. No IM/CM found corelated from the date of degradation. HOSR is degraded on sec-1 from same date. BCCH frequency swap has been done between the TRX5 & TRX 6 on same date. On checking TA pattern, sec B is serving till 6.05km, no change in TA pattern observed. Intersite distance is 5.4km and site is at BSC boundary. No frequency Clash, No LAC mismatch observed.
can anybody calrify me about Phase 3 CSSR degradation