Japan: Expansion of navigation satellite system QZSS
Japan is expanding its navigation satellite program to augment GPS navigation signals for users in the Asia-Pacific region, as spaceflightnow.com reported. The expansion of the Quasi-Zenith Satellite System (QZSS) will be carried out via a $526 million contract with the company Mitsubishi Electric, which will build three navigation satellites to be launched by the end of 2017.
Two of these satellites will be placed in inclined orbits, the third one will operate in geostationary orbit over the equator. The three new satellites will join Japan's firstQZSS satellite, Michibiki, launched in September 2010, thus forming a four-satellite constellation.
According to the Japanese government's Office of National Space Policy, GPS signals are currently only available about 90 percent of the time in Japan, but satellite navigation will be possible 99.8 percent of the time with the QZSS satellites.