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Anomaly of a QZS in Orbit

Jun.05,2018
National Space Policy Secretariat, Cabinet Office 

The Quasi-Zenith Satellite System (QZSS) currently perform the technical confirmation and adjustments for the start of services in November 2018.
On June 2, 2018, an anomaly occurred on the third Quasi-Zenith Satellite (QZS-3, a geostationary satellite that was launched in August 2017). The switching device which selects one of the signal amplifier A and B for the satellite’s L5S signal transmission was unexpectedly flipped and the switch ceased functioning. The satellite’s L5S signal is the test signal which is used for the Positioning Technology Validation Service.

Accordingly, test signal transmission has been temporarily halted to be operated at the check-out of the switching device for QZS-2/ QZS-3 / QZS-4, which are equipped with the same switches.
An investigation will be conducted to determine the cause of this anomaly based on the views of experts who are familiar with related phenomena, and the future operation method will be considered, before restarting test signal transmission.

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