GNSS is a generic term for globally available satellite navigation system. GPS is a GNSS implemented and maintained by the USA. Japan is planning to launch thie

GNSS is a generic term for globally available satellite navigation system. GPS is a GNSS implemented and maintained by the USA. Japan is planning to launch thier own satellites as part of QZSS program, to augment this GPS coverage over Japan. GPS receivers in Japan can make use of these "local" sats along with American sats for more accurate positioning.