abis or ater over satellite will always lead to this situation. The problem is that the MS sends 2 RACH req, because it didn’t receive an answer soon enough (either an accept or a reject)
the 1st rach will get the IMM
the second RACH will also get a IMM but this IMM won’t be “ack” by the MS -> it is this second RACH which is seen as a failure !
what you can try to do is set
RACH retransmit = 0
that should solve your KPI’s issues. but but but… users might experience more “call setup failures”, which won’t be counted in the KPI’s. The 1st RACH request is not received by the BTS (let’s say a noise or a collision with another RACH) – the MS will NOT repeat this RACH. Therefore, the user experiences a failure. But from BSS side, no indicator is incremented.