著者

伊藤 泰義 井上 圭典

出版者

運輸省船舶技術研究所

雑誌

船舶技術研究所報告 (ISSN:0495775X)

巻号頁・発行日

vol.34, no.3, pp.99-140, 1997

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This paper is divided into two parts. Hie first part outline of GPS,while the second part describes the method of fixing the position ,which can minimize the effect of SA, and gives the result of an experiment that attests to the efficacy and advantage of the method. Starting with introductory remarks the first part deals with the following themes : the principle of position fix, code pseudoranges, phase pseudoranges, the kinematic method, the OTF technique, and lastly DGPS network both in Japan and the rest of the world. The second part addresses itself to the following contents: the calculating method of satellite coordinates and its examples, the relationship between the age of ephemeris and the degrees of precision of satellite coordinates, the construction of the observation equation and its solution, the relationship between the stability of the solution and the determinant of the coefficient matrix, examples of inferior precision caused by the effect of SA, and examples in which errors caused by SA are reduced. Whereas the effect of SA normally produces random variation for a fixed position with the error ranging from 50 to 150 meters, our method could reduce the amount of variation of the error by 50 % approximately. A glossary of GPS terminology is appended at the end of the paper.