Location： User Support > NOTICE ADVISORY
Type Description of Notice Advisory to BDS Users (NABU)
Notice Advisory to BDS Users (RNSS) are divided into three categories, namely planned operations, unplanned outages, and others.
Planned operations include orbital maneuvering (RNSS_SCH_ORBMNV), upgrade maintenance (RNSS_UPD_MTNC), on-orbit maintenance (RNSS_SCH_MTNC), plan changed（RNSS_SCH_CHGD）and operation summary(RNSS_SCH_SUM). Orbital maneuvering refers to the adjustment of satellite orbit parameters and attitude, etc., upgrade maintenance refers to software upgrade operations on satellites in orbit, on-orbit maintenance refers to software and hardware maintenance work on satellites in orbit, plan changed refers to the change of time or cancellation of the published but unfinished plan operation, and operation summary refers to providing the exact time of the planned operation after the plan operation is completed.
Unplanned interruption refers to the events that the system service fails to meet the indicator requirements due to unplanned reasons, including unfinished interruption (RNSS_UNSCH_UFN) and service unavailability (RNSS_UNSCH_UNUSABLE). The unfinished interrupt means that the interrupt is still continuing and the end time is waiting for the next notification; Service unavailability refers to an unplanned interruption that has ended and provides the exact start and end time of the interruption.
Other advisory include satellite launch (RNSS_GNR_LAUNCH), satellite commissioning (RNSS_GNR_COM), satellite decommissioning (RNSS_GNR_DECOM) and other information (RNSS_GNR_INFO). Satellite launch means that a new satellite is launched into orbit, satellite commission means that a new satellite officially joins the network to provide services after testing to meet the requirements, satellite decommissioning refers to the ending of a satellite from service due to its lifespan or other reasons, and other information refer to other information that needs to be announced to users during system operation.