Yes,
It is possible.when Uplink RTWP>ifCong(uplink congestion threshold) +iFoffset for IFhyst time period the uplinkcongestion value will be triggered.
Thanks for the reply. but I was rather asking about the external interference. I agree with your comment on UL interference admission limit but is there any measrue to know whether this interference is because of external source? or because of hardware problem?