NAQU is an abbreviation of "NOTICE ADVISORY TO QZSS USERS".

It is the QZSS version of the NANU(NOTICE ADVISORY TO NAVSTAR USERS) which the US Coast Guard Navigation Center gives out for information on GPS.

NAQUs are announced from the MCS to the users to give information of the QZSS status. They include: outage of service, reports of anomaly, forecast of events, etc.

Users will get NAQU messages to read in this web page or to follow the Twitter account: "@QZSS_Status".

Details of NAQU format

NAQU notification times typically vary by NAQU group. Nominal NAQU notification times for the four NAQU groups are summarized in Table

NAQU Group	Nominal Notification Times
Forecast Outages	48 hrs prior to outage start
Unscheduled Outages	Less than 1 hr after outage start
Other	No Nominal - Timing determined on a case-by-case basis
Resumed service	Less than 1 hr after resumed service*
	*There are a few exceptional cases due to failure.

The cell color of the list means below.

Forecast Outages

Unscheduled Outages

Other

Resumed service

The operational status of each satellite operated by QZSS can be confirmed on Constellation status.

Current effective NAQUs that indicate the notice of outage of service, forecast of events, etc. can be confirmed too.

Check Constellation status

* PNT = Satellite Positioning, Navigation and Timing Service, SLAS = Sub-meter Level Augmentation Service,
DC Report = Satellite Report for Disaster and Crisis Management, DCX=Satellite Report for Disaster and Crisis Management（Extended Information）(*),
CLAS = Centimeter Level Augmentation Service, MADOCA-PPP=Multi-GNSS Advanced Orbit and Clock Augmentation - Precise Point Positioning
(*) The trial signal transmission of DCX is planned for January 2024 and operational service of DCX is planned to start in April 2024.
The specification of DCX will be published from October to December 2023.