JPH06102337A - Clock synchronization type system for measuring position of satellite - Google Patents

Abstract

PURPOSE:To realize the reduction of a required installation in space and the efficient utilization of a satellite communication network by using at least one satellite for range for transmitting a radio wave of range and one communication satellite permitting two-way communication between a mobile radio station and a stationary radio station. CONSTITUTION:One communication satellite permitting two-way communication of mobile type and one satellite for range like a GPS satellite for continuously transmitting a radio wave of range are used. And when two-ray communication between a mobile radio station and a stationary radio station is performed, a mobile radio station transmits a radio wave of range by synchronizing the timing at which the radio wave of range from a GPS satellite and the like is received, and the displacement in a reference of time, that is, clock offset TB, is estimated by utilizing a time difference between the time when the radio wave of range is transmitted to a stationary radio station and the arrival time of the radio wave of range from the GPS satellite. Thereby, the continuous measurement of the position of the mobile radio station can be performed by the minimum number of a satellite for range.

Description

Detailed Description of the Invention

[0001]

This invention relates to NAVSTAR / GPS (Naviga
tion System with Time and Ranging / Global Positionin
g System (hereinafter referred to as GPS), a positioning system using a range-finding satellite such as a satellite possessing only a range-finding radio and a communication satellite capable of two-way communication between a mobile radio station and a fixed radio station. Regarding More specifically, for example, in mobile communication using a communication satellite that is already widely used in Japan, the mobile wireless station uses GPS satellites when performing two-way communication between a mobile wireless station and a fixed wireless station. And the like when the distance measurement radio waves reach the fixed wireless station by transmitting the distance measurement radio waves in synchronization with the timing when the distance measurement radio waves are received.
By estimating the clock offset, that is, the clock offset, between the ranging satellite and the mobile radio station by using the time difference from the transmission time of the ranging radio wave of the S satellite, The present invention relates to a clock-synchronized satellite positioning system that enables continuous positioning.

[0002]

2. Description of the Related Art In recent years, traffic control and operation management of moving vehicles such as ships, aircrafts and land vehicles are very important for maintaining the economical efficiency and safety of mobile operations. Two-way mobile communication means with the location determination means and the ground center that manages the operation are essential. This is being recognized in various industrial fields such as courier services.

By the way, as a positioning means, there is a positioning-only system conventionally used such as Loran, Omega, Decker having a radio base station on the ground. In addition, NNSS (NavyNavigation Satellite System), which is already widely used in Japan as a positioning-only system that uses satellites,
tem) and the above-mentioned GPS, which is capable of full service within the past few years, are typical systems, all of which are systems mainly developed and operated by the United States for military use.

Next, as a mobile communication means, there are systems having a wireless base station on the ground such as an MCA system and a car telephone system which are now widely used in Japan. The only Inmarsat satellite system (hereinafter referred to as INMARSAT) operated by the International Maritime Satellite Organization is widely used mainly in the field of ships. But recently
A private company that operates a mobile communication system (hereinafter referred to as OmniTRACS) that tries to provide a two-way message communication service with a mobile unit using a communication satellite normally used for fixed communication appears in the United States, and Has become the focus of attention of private companies.

On the other hand, in the fields of the transportation industry and the traffic administration, which attempt to manage the operation of mobile units, the means for positioning and two-way communication of mobile units are indispensable, and at the same time, they are necessary means. Development of a positioning and communication complex system that is functionally integrated is under consideration. First, VICS that uses wireless equipment such as a large number of sign posts and tele terminals.
(Road traffic information communication system) is the most typical positioning and communication complex system mainly composed of ground communication means, and is currently being developed in cooperation with government agencies and private companies. Next, as a positioning communication complex system using satellites, there is a GEOSTAR system which has already started business in a US private company and is gradually increasing the service content.

As listed above, there are various types of systems that provide the functions of positioning and communication of a mobile body, even if they are limited to the representative ones, and the functions and performances that they achieve are different. The characteristics are also very different.

Whether the positioning means or the mobile communication means, the system using a satellite as a radio wave transmitting / receiving means has a large number of moving bodies scattered over a wide area, as compared with a system using radio equipment on the ground. On the other hand, it has a distinctive feature in that it can provide positioning communication service. Therefore, the use of satellites is an inevitable trend in today's mobile operation management, which is being deployed on a national and global scale.

In the positioning method using the propagation time of radio waves,
By modulating and demodulating this radio wave, it can be used for data communication. Therefore, as shown in the above-mentioned GEOSTAR, the positioning and communication complex system using satellites is becoming an inexpensive and simple means for the user who aims at the operation management of the mobile body.

However, in the communication between the satellite and the mobile body, the radio wave propagation distance is much longer than that in the ground communication, and the mobile body changes its posture even during the communication. Therefore, there are many restrictions on the communication line and The conditions are very strict. Therefore, in the above-mentioned GPS, positioning is possible only by receiving the distance measurement radio wave from the satellite on the mobile body side, and the bidirectional communication function is not originally considered. In GEOSTAR, the data transmission rate is limited to hundreds of tens of bits / second, and finally data communication from a mobile body is possible.
Even in SAT, a relatively expensive satellite tracking antenna is required to enable voice communication. As described above, since mobile communication using satellites has a limitation in bidirectional communication of a large amount of data, the communication cost is higher than that of normal communication. Therefore, establishing an efficient positioning method and communication technology is an important issue in this field.
It is indispensable for reducing the price and usage fee of a mobile user device (hereinafter simply referred to as a user device).

[0010] Such a situation is due to the fact that the positioning communication means are being used in large quantities in land vehicles such as automobiles,
It is becoming an increasingly important issue. That is, for example, GPS is used as a positioning means, OmniTRACS or INMARS
In a positioning communication system that uses ATs as mobile communication means in combination, positioning can be achieved only by receiving distance measurement radio waves, which are said to be free of charge. Therefore, although the usage fee can be reduced, the user device is expensive because it is composed of two types of components.

On the other hand, a GE having a combination of positioning and communication functions.
In OSTAR, since the components of the user equipment are commonly used for positioning and communication, it is highly expected that the price of the equipment will be reduced.

However, the above-mentioned GEOSTAR positioning system is not efficient in terms of the number of satellites used on the communication line, as will be described below. That is, GEOSTA
Fixed radio station on the ground in R (hereinafter simply referred to as ground station)
The distance measurement radio wave transmitted from the satellite is relayed to the satellite and the user device in this order, and the round trip propagation time when the satellite is relayed again to reach the ground station is determined to determine the position of the mobile body. On this occasion,
The mobile positioning function cannot be achieved unless the ranging radio waves relayed by the user equipment are relayed by at least two satellites and transferred to the ground station. Therefore, the communication line from the mobile to the satellite, which is the most severe on the communication line, is occupied by two channels, which limits the number of users that can be accommodated, which is an obstacle to reducing the system usage fee.

From the viewpoint of the needs of navigation and operation management of mobile bodies, GEOSTAR has a slightly inefficient aspect in the positioning system. That is, in the GEOSTAR user device, first, the ranging radio wave transmitted from the ground station is received via one satellite, and the ranging radio wave is returned in synchronization with this reception timing. Next, this distance measurement radio wave reaches the ground station via at least two satellites, and the ground station determines the position of the corresponding mobile body from the time difference between the arrival time and the transmission time of these return radio waves. Therefore, it is necessary to perform bidirectional communication between the ground station and the mobile body at a frequency at which positioning is required, and the ground station must notify the mobile body of the positioning information. As described above, the GEOSTAR positioning system requires a communication frequency that is proportional to the frequency at which positioning information is needed, so GEOSTAR is an inefficient system for users who request almost continuous positioning information.

[0014]

As described above, G
EOSTAR is an extremely effective system in that it provides intermittent positioning and mobile communication services at the same time, and is a powerful method for achieving a low price of user equipment, but continuous positioning is possible and at the same time. In order to reduce the system usage fee, it is desirable to use a positioning method that uses the minimum number of communication satellites and does not increase the number of communications from the user device to the satellite even if the positioning frequency increases.

The present invention has been made in view of the above circumstances, and achieves the following objects. That is, according to the present invention, in continuous two-dimensional positioning using user altitude information, one of the GPS satellites that orbits the earth has a good reception state of the ranging radio wave at the mobile body. Satellite and 1
This can be achieved by applying a satellite capable of mobile communication.
Therefore, the implementation of the present invention does not require a special communication satellite, so that the equipment to be prepared is few. In positioning, bidirectional communication between the ground station and the user equipment is performed only when the clock offset of the user equipment is updated. Therefore, if a stable clock is used for the user equipment, the number of times bidirectional communication is used is reduced. To be done. Therefore, according to the present invention, it is possible to reduce the necessary space facilities and to efficiently use the satellite communication line, so that it is possible to provide the positioning means at a low usage fee.

[0016]

A range-finding satellite that continuously transmits range-finding radio waves W _N , a communication satellite that enables two-way communication between a mobile radio station and a fixed radio station whose installation position is known, and The position of the mobile radio station is determined by using a plurality of satellite tracking stations capable of determining the positions of the range satellite and the communication satellite at any time, and the fixed radio station capable of accurately determining the timing at which the ranging radio waves W _N are transmitted. In the satellite positioning method for determining, the time reference maintaining means CI for accurately maintaining the timing at which the distance measurement radio wave W _N is transmitted in the fixed radio station, and the fixed distance measurement in the fixed radio station. In the mobile radio station, the distance measurement radio wave generation means G1 for continuously transmitting the distance measurement radio wave W _C1 to the communication satellite in synchronization with the timing when the radio wave W _N is transmitted, and the distance measurement radio wave W Keep the exact timing when _N was sent In the time reference maintaining means C2 and the mobile radio station, the distance measurement radio waves W _U1 are transmitted to the communication satellite at a predetermined frequency, that is, relayed, in synchronization with the timing at which the distance measurement radio waves W _N are received. Distance measurement radio wave generation means G
2, the arrival time of the distance measurement radio wave W _U2 , which is transmitted by the communication satellite relaying the distance measurement radio wave W _U1 transmitted by the mobile radio station in the fixed radio station, and the distance measurement radio wave W _C1 . Distance measurement radio wave measuring means M1 for measuring a time difference T _G from the transmitted time
And a ranging satellite determined in the fixed wireless station by using the time difference T _G , orbit data of the ranging satellite superimposed on the ranging radio wave W _N , and position data of the fixed wireless station.・ The fixed inter-station distance S _NG and the radio wave for communication W _G1
By using the synchronization support processing means P1 for performing data processing for notifying the mobile radio station, the arrival time of the distance measurement radio wave W _{N and} the time of the time reference maintaining means C2 in the mobile radio station. The time difference T _{N from the} reference and the time difference T _C between the arrival time of the distance measurement radio wave W _{C2 which} the communication satellite relays and transmits the distance measurement radio wave W _C1 and the time reference of the time reference maintaining means C2 are continuously defined. The distance measurement radio wave measuring means M2 for measuring the position of the mobile radio station in the mobile radio station using the time differences T _N and T _C and the distance between the ranging satellite and the fixed radio station S _NG. And the time difference T _B between the time when the distance measurement radio wave is transmitted from the distance measuring satellite and the time reference of the time reference maintaining unit C2 is updated at a predetermined frequency by using the time difference T _G. Positioning calculation processing means P2 for maintaining position determination accuracy is provided. The mobile radio station position is continuously determined by using at least one distance measurement satellite that transmits range radio waves and one communication satellite that enables bidirectional communication between a mobile radio station and a fixed radio station. It is a clock-synchronized satellite positioning system characterized by enabling the following.

[0017]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 shows the overall configuration of a clock-synchronized satellite positioning system (hereinafter referred to as the present system) according to an embodiment of the present invention. The present system is used for moving vehicles such as ships, aircrafts, automobiles, and people. A large number of mobile radio stations (hereinafter referred to as user devices) carried by (hereinafter referred to as users), fixed radio stations fixedly installed on the ground (hereinafter referred to as ground stations), and one communication satellite 1 It consists of three segments of space radio stations consisting of more than one ranging satellite.

Among these segments, the space radio station comprises means for simply relaying the radio waves transmitted from the user equipment and ground station, and means for simply transmitting the distance measurement radio waves. Communication satellites will be applied to the former, and GPS satellites will be applied to the latter. Therefore, although it is a basic means for implementing the present invention,
Since it is not the subject of this invention, one embodiment of this invention will be described in detail below only with respect to user equipment and ground stations.

2 and 3 show functional configurations of the user equipment and the ground station according to the embodiment of the present invention. 4 and 5 show the principle of the positioning system according to the present invention and the flow of arithmetic processing. These will be described below.

First, in the user equipment, the antenna unit 1
Receives the radio wave W _N transmitted from the ranging satellite and the radio wave W _C1 transmitted in synchronization with the radio wave W _N from the ground station and transmitted by the communication satellite W _C2 , and the reception processing unit 3 receives the received radio wave W _C2. Forward. Here, referring to FIG. 4, the transmission time of the distance measurement radio wave W _C1 transmitted from the ground station coincides with the transmission time of the distance measurement radio wave W _N of the GPS satellite, which is the principle of positioning and clock offset estimation. Is easily understood. Normal,
Since these distance measurement radio waves are repeatedly transmitted, the arrival times of the distance measurement radio waves W _C1 and W _N transmitted at the same time are not used directly for calculating the propagation time.
Actually, the propagation time is calculated in consideration of the above repetition time. The transmission time of the distance measurement radio wave W _C1 is the distance measurement radio wave W _C1.
It does not have to match the transmission time of _N. However, the time difference between the transmission times is known, and this time difference is the distance measurement radio wave W _C1.
It is premised that the information is superimposed on the message and notified to the user device.
In this way, when the relationship between both times is known, it is said that they are synchronized here. The clock unit 2 which is the time reference maintaining unit C2 has a function of generating the time reference shown in FIG. 4 substantially at the time when the ranging satellite transmits the radio wave W _N , and the reception processing unit 3 performs Radio waves W _N and W shown in 4
The time difference T _N and T _C between the reception time of _C2 and the time reference are measured. Therefore, the distance between the user and the ranging satellite is S
_NU, the distance between the user communication satellite S _CU, (referred to as the clock offset or simply offset below) the distance between the ground station and communications satellites S _CG, time difference T _B between the time reference and ranging wave transmission time , And the speed of light is C, the following relational expression is obtained.

[0022]

[Equation 1]

[0023]

[Equation 2] However, δT _NU , δT _CG and δT _CU are radio waves W _N and W _C1.
And W _C2 are propagation time errors that occur during propagation. For reference, when the propagation time error considering the influence of only the earth rotation speed ω _e and the user moving speed υ _u is calculated ,

[0024]

[Equation 3]

[0025]

[Equation 4]

[0026]

[Equation 5] Becomes However, _RU and _RG are the position vectors of the user equipment and ground station with the earth center as the origin, m _NU and
m _CU is a unit vector connecting the user to the ranging and communication satellites, and m _CG is a unit vector connecting the ground station to the communication satellites.

These propagation time errors are correction values that can be calculated with sufficient accuracy even if the above vector values are somewhat inaccurate. Therefore, the satellite-user distances S _NU and S _CU required for the positioning calculation are expressed by the following relational expressions from the expressions (1) and (2).

[0028]

[Equation 6]

[0029]

[Equation 7] Further, there are propagation time errors and the like that occur when the ranging radio waves propagate in the ionosphere and the atmosphere, but these correction methods are problems common to satellite positioning and are not unique to the present invention. I will not say so.

In the positioning calculation processing section 5 which is the positioning calculation processing means P2, as shown in FIG. 5, equations (6) and (7) are used.
User-range-finding satellite distance S _NU determined by the formula, user-
The communication satellite distance S _CU and the user-to-earth center distance S _EU calculated from the user altitude are constantly updated, and the user position is calculated. At this time, the position information of the ranging satellite and the communication satellite is constantly reported to the user device, and the distance S _CG between the ground station and the communication satellite is also known and observed by the satellite tracking station.
If the clock unit 2 has a highly stable clock, the offset T _B does not change rapidly.
Therefore, T _B is a numerical value that can be sequentially updated in consideration of the steady error characteristics of the clock used. The control display unit 6 controls and displays input / output of the user device and is not particularly noteworthy in the present invention.

Next, the clock offset T _B has a property that its error diverges with the passage of time.
Now, for example, stability of the clock used for the clock unit 1
If ^{x10 -10} , an error of 18 m in terms of distance will occur in S _NU and S _CU after 10 minutes. Since this error becomes larger as the elapsed time becomes longer, it is necessary to intermittently estimate the offset T _B. This estimation is performed by relaying the distance measurement radio wave in the user device, and the principle and procedure will be described below.

First, in the user device, the transmission processing unit 4 synchronizes with the timing of the distance measurement radio wave W _N obtained by the reception processing unit 3.
The distance measurement radio wave W _U1 is transmitted to the communication satellite. At this time, a code for identifying the user is superimposed on the distance measurement radio wave W _U1 , and the ground station determines which user the radio wave W _U2 , which arrives by relaying the communication satellite, has been transmitted from. You can

Next, in the ground station, the antenna section 11 shown in FIG.
Receives the radio wave W _U2 transmitted by the user apparatus and relayed by the communication satellite, and transfers the radio wave W _U2 to the reception processing unit 13 which is the distance measurement radio wave measuring means M1. The reception processing unit 13 determines from which user the radio wave W _U2 is transmitted, and measures the time difference T _G between the reception time of the radio wave W _{U2 and} the transmission time of the radio wave W _C1 shown in FIG. These are notified to the positioning support processing unit 15 which is the synchronization support processing means P1. The positioning support processing unit 15 is means for creating data necessary for positioning calculation on the user side and estimation of the clock offset T _B , and the distance measurement radio waves W of the communication satellites observed by a plurality of satellite tracking stations.
The position of the communication satellite, the distance-measuring satellite / ground station distance S _NG, etc. are calculated from _C2 and the distance-measuring radio wave W _N , and the transmission processing unit 14 which is the distance-measuring radio wave generation means G1 is notified together with the time difference T _G.

The transmission processing section 14 is a distance measuring radio wave W _N held by the clock section 12 which is the time reference maintaining means C1 of the ground station.
In synchronism with the transmission timing of, the distance measuring radio wave W _{C1 on} which the position data of the communication satellite, the distance measuring satellite-ground station distance S _NG, or the position data of the ground station is superimposed is transmitted to the communication satellite. In addition, the transmission processing unit 14 sends the reception processing unit 13 to each user.
The time difference T _G measured in step 1 and the user's identification code are transmitted to the communication satellite. Normally, the radio wave W _G1 for communication is applied to this radio wave, and data for clock synchronization is reported to each user in a time division manner. To do. However, since it is not necessary to transmit these data in synchronization, it is possible to make a notification by using a radio wave for message communication shared by users. The communication control unit 16 is a means for controlling and monitoring such a communication line with each user, and at the same time, manages and processes a message from each user and sends a message to each user.

On the user side, as shown in FIG. 4, the time difference T _G measured by the ground station from the radio wave W _G2 relayed by the communication satellite of the radio wave W _G1 transmitted by the ground station in the reception processing unit 3. Is read and the positioning calculation processing unit 5 is notified.

By the way, referring to FIG. 4, the time difference T
_It can be seen that _G is expressed by the following relational expression.

[0037]

[Equation 8] However, δT _NU , δT _CG and δT _CU are (3) to (5)
It is the propagation time error already defined in the equation.

Then, by substituting the equations (1) and (2) into the equation (8),

[0039]

[Equation 9] Therefore, the clock offset T _B is

[0040]

[Equation 10] Then, the offset T _{B of the} user clock can be estimated by correcting T _N and T _C measured by the user equipment, T _G measured by the ground station, and the calculation of the propagation time error that can be calculated.

As described above, the clock offset T _B is estimated by the positioning calculation processing section 5 while the measured value T _G timely reported from the ground station and T _N and T _C continuously measured by the user equipment are estimated. If the measured values T _N and T _C are reported to the ground station side, the user position can be determined and clock synchronization can be performed on the ground station side.

In the thus configured clock-synchronous satellite positioning system, user position measurement can be performed by a minimum of two satellites, a communication satellite and a ranging satellite. Enables three-dimensional positioning without using the user altitude data. In addition, a system form in which another communication satellite that relays the ranging radio waves transmitted from the ground station is used as a ranging satellite is also conceivable, but in principle, these can be achieved based on the same positioning principle as above. Is.

Further, as one embodiment of the present invention, the clock unit 2 and the clock unit 12 of the user equipment and the ground station.
Therefore, if a highly stable clock is applied, the number of bidirectional communications required for estimating the user clock offset T _B can be reduced. Therefore, a calibration method for improving the stability of the clock is extremely important for carrying out the present invention, but this method is in principle disclosed in JP-A-63-2.
This is similar to the method described in No. 66375. That is, calibration because it can calculate the time rate of change W _TB of the calculated clock offset T _B from the tendency of divergence of the position data of the user equipment, the user equipment calculates the W _TB in the positioning calculation processing unit 5, this clock unit Or the clock offset T used when calculating equations (6) and (7)
It can be used as a correction value when updating _B by the following formula.

[0044]

[Equation 11] However, T _B (t ₀ ) is the clock offset estimated at time t ₀ based on the above procedure, and T _B (t) is the offset at time t updated by the correction value W _TB .

[0045]

As described above in detail, according to the present invention, one communication satellite capable of two-way mobile communication and one distance measuring device such as a GPS satellite continuously transmitting distance measuring radio waves. If the satellite can be used, the reception time of the distance measurement radio wave at both the mobile radio station and the fixed radio station and the reception time of the distance measurement radio wave transmitted in synchronization with this and then relayed by the communication satellite are set. By providing the measuring means, continuous positioning can be performed by the mobile radio station. For this reason, it has become possible to construct a system that provides positioning and communication services at the same time by utilizing the already launched communication satellites and ranging satellites.

The features and effects of the system implemented according to the present invention can be summarized as follows. First
In addition, the present system can simultaneously provide positioning and communication services by using two satellites, a GPS satellite and a communication satellite, which are positioned at an angle of 20 to 30 degrees apart.
Therefore, a large number of GPS satellites and similar ranging satellites will be deployed in the future, so that the space facility required to implement the positioning and communi- cation composite service will be the minimum scale and a system having positioning and communication functions. As a result, the operating cost will be extremely small.

Second, as a satellite positioning system for performing high-frequency positioning by a mobile user using the minimum number of satellites, the amount of satellite communication lines used is higher than that of other positioning communication complex systems such as GEOSTAR. The least. Therefore, even if the satellites have the same communication capability, the positioning communication service can be simultaneously provided to more mobile users.

Third, in the GPS positioning system, three or more G
Although it is necessary to receive the ranging radio waves from the PS satellites at the same time, due to the restriction of the number of GPS satellites arranged, the frequency of loss of the positioning function or the deterioration of the positioning accuracy increases in urban areas and mountain areas. However, in this system, many Gs are arranged.
If the distance measurement radio waves of one GPS satellite and one communication satellite in the PS satellite can be received, the positioning function will be maintained,
The frequency of positioning functions being interrupted in urban areas and mountains will be reduced. Further, if a geostationary satellite is applied as the communication satellite, the elevation angle thereof is 40 to 50 degrees, so that the reception state of the distance measurement radio wave is relatively good in this respect as well. Therefore, this system achieves a continuous positioning function even in urban areas and mountainous areas where many distance measuring radio waves are blocked.

[Brief description of drawings]

FIG. 1 is a diagram showing an overall configuration of a clock synchronous satellite positioning system according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a main functional configuration of a user apparatus (mobile radio station) according to an embodiment of the present invention.

FIG. 3 is a block diagram showing a main functional configuration of a ground station (fixed radio station) according to an embodiment of the present invention.

FIG. 4 is a diagram showing the time difference T _N , T _C , and T _G of arrival times of various range-finding radio waves, which are basic measurement contents in the implementation of the invention.
And the distance between satellites and radio stations S _CU , S _CG , S _NU and S _NG
With the clock offset T _{B of the} user equipment
It is a figure which shows the relationship with.

FIG. 5 is a flowchart showing a general calculation processing procedure for determining a user position vector R _U by using the measured arrival time difference.

[Explanation of symbols]

1 ... Antenna part (user device), 2 ... Clock part (user device), 3 ... Reception processing part (user device), 4 ... Transmission processing part (user device), 5 ... Positioning calculation processing part (user device), 6 ... control display unit (user device), 11 ... antenna unit (ground station), 12 ... clock unit (ground station), 13 ... reception processing unit (ground station), 14 ... transmission processing unit (ground station), 1
5 ... Positioning support processing unit (ground station), 16 ... Communication control unit (ground station)

Claims (1)

[Claims] 1. A range-finding satellite that continuously transmits range-finding radio waves W _N , a communication satellite that can perform two-way communication between a mobile radio station and a fixed radio station whose installation position is known, the range-finding satellite and the range-finding satellite. Multiple satellite tracking stations that can determine the momentary position of communication satellites,
In the satellite positioning method for determining the position of a mobile radio station by using the fixed radio station that can accurately determine the timing of transmission of the radio wave W _N, time reference maintaining _{means N} to accurately maintain timing transmitted (C
1) and a distance measuring radio wave generating means in the fixed wireless station for continuously transmitting a distance measuring radio wave W _C1 to the communication satellite in synchronization with the timing when the distance measuring radio wave W _N is transmitted ( G1) and a time reference maintaining means (C) for accurately maintaining the timing at which the distance measurement radio wave W _N is transmitted in the mobile radio station.
2) and, in the mobile radio station, the ranging radio wave W is transmitted to the communication satellite in synchronization with the timing of receiving the ranging radio wave W _N.
A distance measurement radio wave generation means (G2) for transmitting _U1 at a predetermined frequency, that is, for relaying, and the communication satellite relaying the distance measurement radio wave W _U1 transmitted by the mobile radio station in the fixed radio station. Distance measuring radio wave measuring means (M1) for measuring a time difference T _G between the arrival time of the distance measuring radio wave W _U2 transmitted by transmitting the distance measuring radio wave W _{U2 and} the time of transmitting the distance measuring radio wave W _C1.
And a ranging satellite determined in the fixed wireless station by using the time difference T _G , orbit data of the ranging satellite superimposed on the ranging radio wave W _N , and position data of the fixed wireless station. A synchronization support processing means (P1) for performing data processing for notifying the mobile radio station of the fixed inter-radio station distance S _NG using a radio wave W _G1 for communication; the distance measuring radio waves W and time difference T _N of the time reference of the arrival time and the time reference maintaining means (C2) of _N, ranging wave W _C2 of the communication satellite transmits the relaying the distance measuring radio waves W _C1 Distance measuring radio wave measuring means (M2) for continuously measuring a time difference T _C between the arrival time of the time and the time reference of the time reference maintaining means (C2), and the time differences T _N and T in the mobile radio station. position of the mobile radio stations by using the distance S _NG between _C and the distance measuring satellite fixed radio station And it determines continuously, the time difference T _G
Positioning that updates the time difference T _B between the time when the distance measuring radio wave is transmitted from the distance measuring satellite and the time reference of the time reference maintaining unit (C2) at a predetermined frequency to maintain the position determination accuracy of the mobile radio station. A calculation processing means (P2) is provided, and at least one distance measuring satellite transmitting distance measuring radio waves and one communication satellite capable of bidirectional communication between a mobile wireless station and a fixed wireless station are used. A clock-synchronized satellite positioning system that enables continuous determination of mobile radio station positions.