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GPS and its Civil Application in Japan INTRODUCTION The purpose of this paper is to construct a framework for understanding the commercial implications of the Global Positioning System (GPS) and its applications in Japan. Most literature, while touching upon GPS, tends to concentrate on the technicality of how GPS works, seems to be overlook the user’s segment and commercial market where the bulk of revenues are generated. I choose Japan as a case study because Japan is a place where the civilian (commercial) applications of GPS are at high speed of development. Therefore, in this paper, I will first give a brief overview of GPS and its use in the world. Then I will discuss about to what extent and in what aspects GPS has been applied for civilian use in Japan. GPS AND ITS BRIEF HISTORY The Global Positioning System—GPS, is installed 24 Navstar satellites in six orbital planes. Each plane is settled four satellites that rotated with circular 20,200-kilometer orbits at an inclination angle of 55 degrees and a period of 12 hours. The configuration makes the satellites appearing in the same position at the same sidereal time each day. Because the location will be observed by at least five satellites from anywhere at any time, a GPS receiver can receive the signals from at least three of these satellites. Thus, a position can be determined (El-Rabbany, 2002; Muller, 2000) To determine the position, it is necessary to calculate the timing differences from at least three signals which are encoded. Each satellite transmits a signal including its orbital elements, clock behavior, system time, and status massages. A contained calendar provides the estimated data for each active satellite, and all satellites have to be located once the first one has been successfully confined. The raw data from satellites can be displayed in some ways such as local time, Universal Time, Standard time. The date acts as an alarm clock, and can calculate sunrise and moonrise, as well as define position, travel direction, speed, and estimate arriving time (El-Rabbany, 2002; Parkinson & Spilker, 1996). The twenty-four active GPS satellites orbit 11,000 nautical miles above the Earth. Each GPS satellite sends radio signal containing its code, orbital position, and exact time. Comparing the time which takes for signals to arrive from three or more satellites, a GPS receiver can determine [the own exact coordinates] because each satellite is at a recognized position in space (El-Rabbany, 2002; Muller, 2000; Parkinson & Spilker, 1996). (Source: National Defense Academy in Japan Official Web Site http://www.nda.ac.jp/cc/users/nami/GPS/outline.html) (Source: Source: National Defense Academy in Japan Official Web Site http://www.nda.ac.jp/cc/users/nami/GPS/carrier.html) The first navigation system was the U.S. Navy’s Navigation Satellite System introduced in 1960s, and by 1973, there came a new innovating navigation system planned and completed by a small group of armed forces officers and civilians in the Pentagon. It was based on radio lining up to artificial satellites which were called NAVSTARs (Parkinson & Spilker, 1996). Since then, the GPS system had been upgraded on continuous basis with a huge cost of $13 billion dollars over nearly 2 decades (Muller, 2000). The first success application of GPS system was seen during the first Gulf War in 1991 when United States forces used the system for navigation and targeting. During the War, U.S. tanks depended on GPS to find their direction around the desert in Iraq and Saudi Arabia. Since then, there has been an increased demand for GPS in world market, not just for military purposes, but more for civilian use. GPS is now used in car navigation, and the on-screen and voice instructions can point out the location on the digital map and chart a path with real-time route guidance for drivers. Today, anyone who carries a GPS receiver, in anywhere in the world, is ensured to almost instantaneously get free benefit from the GPS system for navigational purposes (Wilson, 2002). In its applications, the GPS has proved itself to have more civilian utility than military use. Because of this, the code structure has thus been designed into two coded—the P code used by military, and the C/A code used by civil users. Its civilian utility has been expended from its initial use for accurate time transfer to its current use for survey in marine, air, land, and even space. Now the number of civil users is over more than 10 times than military users. With cost decreasing, it is expected that the number of civil users would increase rapidly (El-Rabbany, 2002; Parkinson & Spilker 1996). What follows is a list of some major civil applications. o Public safety (i.e., ambulance route navigation and wireless 911) o Recreational vehicle navigation (land, air or marine vehicles) o Other recreational/gaming (such as hunting and fishing devices) o Automotive /intelligent vehicle navigation o Asset tracking o "Smart" agriculture o Mining and geological applications o Construction/civil engineering applications o Marine surveying and oceanography o Precision Timing (including personal locating and wireless) (El-Rabbany, 2002; Muller, 2000; Newton, 2001; Parkinson & Spilker, 1996).
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