CS Call drop caused by Blind Detect switch after RNC upgrade

[jukreew]

CS Call drop caused by Blind Detect switch after RNC upgrade (Huawei document)

At G country GU swap project,after RNC was upgraded from SPC 600 to SPC700,the RNC CS call drop rate was worsen from 2% to 7%.Most of cause is RF cause.From performance,the reason is VS.RAB.Loss.CS.SRBReset;from the data of trace,the reason is failure in the radio interface procedure.