circuit group unblocking (mobile communications) (CGU)
Circuit Group Unblocking (CGU) is a message for unblocking blocked GSM user channels. The CGU message has the opposite function of Circuit Group Blocking( CGB), the blocking function. One CGU command can unblock up to 32 channels at a time.
The CGUA message is the acknowledgement message for the unblocking (CGU) of a group of user channels.