Issue 34

Japan Launches QZS-1R Navigation Satellite

26 October 2021: Japan launched the QZS-1R position, navigation and timing (PNT) satellite aboard H-IIA rocket from LA-Y1 from the Tanegashima Space Center. The QZS-1R satellite will join other satellites as a part of the Quasi-Zenith Satellite System, or QZSS, which is a satellite navigation system for Japan. QZS-1R…

26 October 2021: Japan launched the QZS-1R position, navigation and timing (PNT) satellite aboard H-IIA rocket from LA-Y1 from the Tanegashima Space Center. The QZS-1R satellite will join other satellites as a part of the Quasi-Zenith Satellite System, or QZSS, which is a satellite navigation system for Japan. QZS-1R is now in its inclined geostationary orbit (IGSO).

– QZS-1R joins 4 other QZSS spacecraft. The QZS-1R’s orbit is inclined 34°. The inclination of the other QZSS satellites varies. Orbits are optimized for providing PNT services to Japan.

– The QZSS constellation is designed to improve the accuracy of the US GPS constellation for Japanese users in urban areas. The QZS-1R will replace the QZS-1 once it becomes operational.

– The first satellite (QZS-1) was launched on 11 Sep 2010 and now past its designed 10-year life service.

– Japan launched an additional three satellites (two with a quasi-zenith satellite orbit [QZO] and one with a geostationary orbit [GEO]) in FY2017.

– Plans are set to add three more satellites to the QZSS in 2023 to bring the constellation to 7 operational satellites.

QZSS can be used in an integrated way with GPS, ensuring a sufficient number of satellites for stable, high-precision positioning. QZS are compatible with GPS and receivers can be procured at a low cost. The quasi-zenith orbit (QZO) for QZSS is shaped like a figure eight with north-south asymmetry. This makes satellites on this orbit spend more time in the northern hemisphere (around 13 hours versus 11 hours in the southern hemisphere) and remain visible from Japan for a long period of time.

Japan Launches QZS-1R Navigation Satellite

Original PDF links: Source 1 · Source 2