Abstract: A positioning system and method utilizing a plurality of artificial satellites, in which times of positioning time signals transmitted from at least four artificial satellites to a positioning available area are always made coincident with a standard time of a ground control station to maintain accuracy of the time. In the ground control station, phases of a receive PN code obtained from the time signal included in the positioning signal of the artificial satellite and a pseudo receive PN code obtained by delaying the standard time of the ground control station by a radio wave propagation time, measured in real time, corresponding to a range between the ground control station and the artificial satellite are compared, and from the detected time error, a time correction command signal is obtained and is transmitted to the artificial satellite to correct the time of the positioning time signal of the artificial satellite.

Abstract: A method of positioning an observation point utilizing artificial satellites. In order to make it possible to make a range measurement in areas within the latitude of 65 degrees where almost all people in the world reside, a predetermined first number of satellites, for example, ten satellites are placed in geosynchronous orbits, the inclination angle thereof being set to about six degrees. The respective satellites are placed so that the mean anomalies thereof are equally separated. A control station, which keeps track of a predetermined second number of satellites, monitors signals indicating times and frequencies generated from the satellites and compares the times and frequencies with national standard time and frequency obtained in a ground station, thereby enabling the position of the observation point to be determined. The control station frequently transmits commands for compensating clocks mounted in the satellites whereby each satellite generates a highly accurate signal for range measurement.

Abstract: A method of determining the position of an observation point on the earth using M satellites on geosynchronous orbits having predetermined orbit inclination angle such that N (<M) satellites are in the range of vision of the observation point. One of the N satellites generates a reference signal at a known time. This reference signal is sent directly to the observation point, sequentially relaved to the remaining subsequent satellites and transmitted from the respective satellites in order upon receiving the reference signal from a preceding adjacent satellite to the observation point. The observation point measures the differences in time of reception of the signals from the N satellites. The position of the observation point is determined as an intersecting point of the hyperboloids each having foci on adjacent two of the satellite positions.

Abstract: A method of determining the position of an observation point on the earth using M satellites on a stationary orbit which has a predetermined orbit inclination angle such that N (<M) satelites are in the range of vision of the observation point. One of the N satellites generates a reference signal at a known time. This reference signal is sent directly to the observation point, sequentially relayed by the remaining satellites and transmitted from the respective satellites to the observation point. The observation point measures the differences in time of reception of the signals from the N satellites and determines the positions of the N satellites. The position of the observation point is determined as an intersecting point of the hyperboloids each placing the foci on adjacent two of the satellite positions.