ParaHO, what are you talking about ?
GSM Edge Radio Access Network.. That’s the name of a 2G network.
IK, a mobile doesn’t get latched because it cannot perform a location update, it means (as far as i know):
1/ the network rejects the IMSI
2/ or, the IMSI forbids the network
3/ or, the coverage is indeed too low (C1 is negative)
4/ the mobile cannot hear the band 1800 MHz. Is your mobile biband ?
I can help you only on point number 3:
Set your radio parameters at the following values:
RXLev Access Min = -110dBm
MS TxPower Max CCH = 33dBm