The GPS or Global Positioning System, which first became popular as a means of car navigation have become widespread with their integration in mobile phones. A navigation signal can point to an exact location with the help of at least four satellites but in areas whose geographical terrains are populated with mountains, the satellites signals can be hampered by their presence and the same is true in urban areas where skyscrapers abound. Mountains, skyscrapers and other tall structures, manmade or otherwise, can cause signal errors. The QZSS and the BeiDou-2 Satellite Systems were launched to remedy such situations.
In 2003, Japan launched the Quasi-Zenith Satellite System that will provide a regional satellite positioning service in addition to communication and broadcasting services. This is the first satellite positioning of Japan and it is a joint effort of government and private sectors. The Advanced Satellite Business Corporation or ASBC is a private company that is tasked with the development and operation of the communications and broadcasting functions of the satellite system. Four ministries of the Government, on the other hand, are tasked with the development of the satellite positioning system.