Japan has developed its own satellite navigation system called QZSS (Quasi-Zenith Satellite System), which complements existing global navigation systems like GPS. This system enhances the accuracy and availability of positioning services in urban canyons and mountainous areas, demonstrating Japan's commitment to technological advancement and self-reliance in critical infrastructure. Understanding such national systems is relevant for UPSC Prelims as it highlights the geopolitical dimensions of space technology and its implications for national security and economic development.