An estimation device, earth station, system, method, and program for estimating the location of a signal source.

Abstract

An estimation device and the like are provided that estimate the position of a signal source that generates a signal while rotating the direction of the main lobe. [Solution] An estimation device (123) that estimates the position of a signal source that generates a signal while rotating the direction of a main lobe includes: a reception time and positional displacement relationship determiner (124) that determines, for a set of multiple received signals of the rotating main lobe signal received at different positions and different times, the reception time and positional displacement relationship due to main lobe rotation based on the rotation angular velocity of the main lobe, the reception time difference of the multiple received signals, the position of the receiver at the time the multiple received signals were received, and the position of the signal source that generated the main lobe at the time the multiple received signals were received; and an estimation unit (125) that estimates the position of the signal source based on the determined reception time and positional displacement relationship.

Description

[Technical Field]

[0001] The present disclosure relates to an estimation device, an earth station, a system, a method, and a program for estimating the position of a signal source, particularly a signal source that generates a signal while rotating the direction of its main lobe. [Background technology]

[0002] Systems for estimating the location of unknown signal sources are being researched. Location estimation systems that use the difference in reception time or frequency of radio waves as signals are location identification algorithms that assume signals are transmitted from the same source at the same time. Methods that use time or frequency differences suffer from significant reductions in location estimation accuracy due to time errors and frequency estimation errors in each receiver. Furthermore, if the beam width of the transmitting radio waves is narrow, the observation device must be positioned in a straight line with the transmitting source in order to capture signals from the same source at the same time, which limits the range in which location can be identified. Previous research on location identification based on radar rotation (Non-Patent Document 1) assumes that the radar rotation angular velocity is known, which limits the conditions for use. [Prior art documents] [Non-patent literature]

[0003] [Non-Patent Document 1] Hubacek, Petr, Jiri Vesely, and Jana Olivova. "Radar Position Estimation by sequential irradiation of ESM receivers." Sensors 21.13 (2021): 4430. Summary of the Invention [Problem to be solved by the invention]

[0004] The present invention has been made to solve the above-mentioned problems, and aims to reduce the effects of time errors and frequency estimation errors on position estimation accuracy, and to enable position estimation even when the rotation angular velocity of the main lobe of radio wave radiation from a signal source is unknown. [Means for solving the problem]

[0005] 1. An estimation device according to one embodiment of the present invention is an estimation device that estimates the position of a signal source that generates a signal while rotating the direction of a main lobe, and includes: a reception time and positional displacement relationship determiner that determines, for a set of multiple received signals of the rotating main lobe signal received at different positions and different times, the reception time and positional displacement relationship caused by main lobe rotation based on the rotation angular velocity of the main lobe, the reception time difference between the multiple received signals, the position of the receiver at the time the multiple received signals were received, and the position of the signal source that generated the main lobe at the time the multiple received signals were received; and an estimation unit that estimates the position of the signal source based on the determined reception time and positional displacement relationship.

[0006] The reception time and positional displacement relationship determination unit described in Section 2.1 may determine an same-frequency relationship for a set of two signals of the same frequency of the rotating main lobe received by two different receivers, based on the rotational angular velocity of the main lobe, the reception time difference between the signals of the same frequency, the positions of the receivers at the reception times of the signals of the same frequency, and the position of a signal source that generated the main lobe; and determine an different-frequency relationship for a set of two signals of different frequencies of the rotating main lobe received by the same moving receiver, based on the rotational angular velocity of the main lobe, the reception time difference between the signals of the two different frequencies, the positions of the receivers at the times when the signals of the two different frequencies were received, and the position of the signal source that generated the main lobe; and the estimation unit may estimate the position of the signal source based on at least one of the determined same-frequency relationship and the determined different-frequency relationship.

[0007] 3. The estimation device according to item 2, wherein the same-period relationship is the relationship shown in the following formula 1, and the different-period relationship is the relationship shown in the following formula 2.

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[0008] 4. The estimation unit may be an estimation device as described in paragraph 2 or 3, which determines the same period relationship for a plurality of pairs, determines the different period relationship for a plurality of pairs, and estimates the position of the signal source using maximum likelihood estimation based on the determined same period relationships and different period relationships.

[0009] In the estimation device described in Section 5.4, the maximum likelihood estimation uses Equation 5, which is defined by the following Equations 3 and 4, as an objective function, and the position of the signal source (p e ) and the rotation angular velocity (ω) of the main lobe may be estimated.

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[0010] 6. In one embodiment, the earth station may include the estimation device described in items 1 to 5.

[0011] 7. In one embodiment, an estimation system can include the estimation device described in items 1 to 6 and one or more receivers that receive signals from a signal generating source that generates signals while rotating the direction of the main lobe.

[0012] 8. The receiver in paragraph 7 may be an artificial satellite.

[0013] 9. The method of this embodiment is a method for estimating the position of a signal source that generates a signal while rotating the direction of a main lobe, and for a pair of two received signals of the rotating main lobe signal received at different positions and different times, determines the reception time and positional displacement relationship due to main lobe rotation based on the rotation angular velocity of the main lobe, the reception time difference between the two received signals, the position of the receiver at the time the two received signals were received, and the position of the signal source that generated the main lobe at the time the two received signals were received; The location of the signal source is estimated based on the determined reception time and positional displacement relationship.

[0014] 10. The program of this embodiment can cause the method described in item 9 to be executed by one or more computers.

[0015] 11. An estimation device according to one embodiment of the present invention for estimating the position of a signal source that generates a signal while rotating the direction of a main lobe comprises: means for determining a reception time and position displacement relationship that determines a reception time and position displacement relationship due to main lobe rotation for a pair of two received signals of the rotating main lobe signal that are received at different positions and different times, based on the rotation angular velocity of the main lobe, the reception time difference between the two received signals, the position of the receiver at the times that the two received signals were received, and the position of the signal source that generated the main lobe at the times that the two received signals were received; and means for estimating the position of the signal source based on the determined reception time and position displacement relationship. [Effects of the Invention]

[0016] One embodiment of the present invention has been made to solve the above-mentioned problems, and can reduce the impact of time errors and frequency estimation accuracy on position estimation accuracy. Since it is not necessary to simultaneously capture the main lobe of a signal emitted from a signal source with multiple radio wave receivers, position estimation is possible even when the signal beam width is narrow. Furthermore, position estimation is possible even when the rotation angular velocity of the main lobe of the radio wave radiation from the signal source is unknown. [Brief explanation of the drawings]

[0017] [Figure 1] 1 is a diagram illustrating a configuration of a position estimation system according to an embodiment. [Figure 2] FIG. 2 is a diagram showing a detailed configuration of a receiver and an earth station including an estimation device. [Figure 3] 1 is an example of an operation flowchart of an estimation system including an estimation device according to an embodiment. [Figure 4] 10 is an example showing an estimated position using an embodiment. [Figure 5] 10 is an example showing an estimated position using an embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0018] An estimation device, an earth station, a system, a method, and a program for estimating the position of a signal source according to embodiments of the present invention will be described with reference to the drawings.

[0019] Fig. 1 is a diagram showing the configuration of an estimation system for estimating the position of a signal source according to this embodiment. As will be described in detail below, the estimation system 1 shown in Fig. 1 is a system that receives signals such as radio waves and estimates the position of the signal source based on the received signals. The estimation system 1 can be used as a radio wave monitoring system.

[0020] The estimation system 1 is a system for estimating the position of a signal source 10 whose location is unknown, and includes a signal receiver 11 and an earth station 12. The signal source 10 emits a signal while rotating a main lobe 14 at a constant rotational speed. Typically, the signal source 10 includes a radar that emits radio waves as a signal from a rotating antenna.

[0021] The signal receiver 11 receives signals such as radio waves and transmits information about the received signals to the earth station 12, and an estimation device provided in the earth station 12 estimates the position of the signal source based on the information about the received signals. The signal receiver 11 may be any device capable of receiving signals such as radio waves from, for example, a radio wave receiving tower, a ship, an artificial satellite, an aircraft including an unmanned aerial vehicle, etc. Although only one mobile signal receiver 11A and one stationary signal receiver 11B are shown in FIG. 1, the estimation system 1 includes at least one mobile signal receiver 11A or multiple stationary signal receivers 11B.

[0022] In this specification, the signal receiver 11 is an artificial satellite 11A and an anchored ship 11B. The artificial satellite can move around the Earth on a satellite orbit. The satellite orbit can be, for example, a low Earth orbit (LEO), a medium Earth orbit (MEO), or a geostatinary Earth orbit (GEO), but is not limited to these. In FIG. 1 , the artificial satellite 11A moves along a predetermined satellite orbit 13. For example, the signal receiver 11 is located at position 11At0 at time t0, moves to position 11At1 at time t1, and moves to position 11At2 at time t2. On the other hand, the anchored ship 11B is assumed to be stationary in this embodiment. The earth station 12 is located on the Earth, receives signals from the signal receiver, and estimates the position of the signal source 10.

[0023] The signal receiver 11 includes a control device 110, a storage device 111, a communication transceiver 112, a receiver 113, and a position information acquisition device 114, and may also include other components for realizing various functions. If the signal receiver 11 is an artificial satellite, it may include a power supply subsystem including a solar panel, a battery, etc., for supplying power to each device mounted on the signal receiver 11, an attitude control subsystem for controlling the attitude of the signal receiver 11, a propulsion subsystem for propelling the signal receiver 11, a thermal control subsystem for controlling the temperature range within the signal receiver 11, etc.

[0024] In this embodiment, the receiver 113 is a receiving device that receives radio waves as signals and includes a receiving antenna. The signal may be, for example, an electromagnetic wave having a frequency of 3 THz or less, but is not limited to this. For example, it may be any signal, such as infrared light, that is emitted with a certain directionality. The receiver 113 receives, for example, radio waves arriving from the Earth. In this embodiment, the Earth refers to the ground and / or the sea, but the radio waves that the receiver 113 can receive are not limited to these. In other words, radio wave sources may include equipment installed on the ground, mobile objects that can move on the ground, ships on the sea, aircraft above the ground or sea surface, and spacecraft in outer space.

[0025] The position information acquisition device 114 acquires position information of the signal receiver 11. The position information acquisition device 114 calculates the position of the signal receiver 11 based on, for example, a signal from a Global Navigation Satellite System (GNSS). In this embodiment, the communication transceiver 112 is a device that receives command signals from the earth station 12 and transmits telemetry signals to the earth station 12, and includes a communication antenna. The command signals are signals that include command data for controlling the signal receiver 11. The command signals are signals that the control device uses to control each component, and are transmitted from the communication transceiver 112 to the control device 110. The telemetry signals are signals that include telemetry data that indicate the status of the signal receiver 11. The communication transceiver 112 demodulates the received command signals and outputs the demodulated signals to the control device 110. The communication transceiver 112 modulates the telemetry signals and transmits them to the earth station 12 via the communication transceiver 112.

[0026] The control device 110 is configured with one or more computers and / or one or more processing circuits, and performs overall control of the signal receiver 11. For example, the control device 110 can control the memory device 111, the communication transceiver 112, the receiver 113, and the position information acquisition device 114. The control device 110 determines the time at which the receiver 113 received a signal from a signal source, and acquires information indicating the position of the signal receiver 11 at that time from the position information acquisition device 114. Then, the control device 110 transmits the determined reception time and information indicating the position at that reception time to the earth station 12 via the communication transceiver 112.

[0027] The storage device 111 is configured with a memory and / or storage, and stores information necessary for controlling the signal receiver 11. The storage device 111 may store a program necessary for controlling the signal receiver 11, and each device may be realized by executing this program on one or more computers and / or one or more processing circuits, or these functions may be realized by hardware by configuring electronic circuits, etc., to realize some or all of the functions.

[0028] The earth station 12 is a system that communicates with the signal receiver 11. The earth station 12 may be fixedly installed on the ground, or may be deployed on a mobile object that can move on the ground, on the sea, or above the ground or sea surface. The earth station 12 includes a control device 120, a storage device 121, a communication transceiver 122, and an estimation device 123.

[0029] The communications transceiver 122 includes an antenna for transmitting command signals and receiving telemetry signals, and generates and transmits command signals by modulating control signals for the signal receiver 11. The communications transceiver 122 also receives and demodulates telemetry signals and outputs the results to the control device 120. The communications transceiver 122 further receives information indicating the time of reception of the signal transmitted from the signal receiver 11 and the position of the signal receiver at the time of reception.

[0030] The control device 120 is configured to include an input / output device, and a computer and / or a processing circuit, and generates a control signal for the signal receiver 11. It also stores information indicating the reception time of the signal by the signal receiver 11 received by the communication transceiver 122 and the position of the signal receiver at the reception time in the memory device 121, and reads out the information indicating the reception time and position stored in the memory device and inputs it to the estimation device 123.

[0031] The storage device 121 is configured with a memory and / or storage, and stores information necessary for controlling the earth station 12. The storage device 121 may store programs necessary for controlling the mobile object, and each device may be realized by executing these programs on one or more computers and / or one or more processing circuits, or these functions may be realized by hardware by configuring electronic circuits or the like for realizing some or all of the functions. The storage device 121 can further store information indicating the time of reception of the signal by the signal receiver 11 and the position of the signal receiver at the time of reception.

[0032] The estimation device 123 is configured with one or more computers and / or one or more processing circuits and storage devices, and estimates the position of a signal source based on a signal such as a radio wave received by the signal receiver 11. The estimation device 123 includes a reception time and positional displacement relationship determination unit 124 and a position estimation unit 125. These devices may be realized by one or more computers and / or processing circuits executing a program stored in the storage device 121 in the earth station 12, or these functions may be realized by hardware by configuring electronic circuits or the like to realize some or all of the functions.

[0033] The reception time and positional displacement relationship determination unit 124 determines the reception time and positional displacement relationship due to main lobe rotation for a set of multiple reception signals of a rotating main lobe signal received at different times at different positions, based on the rotation angular velocity of the main lobe, the reception time difference between the multiple reception signals, the position of the receiver at the time the multiple reception signals were received, and the position of the signal source that generated the main lobe. The set of reception signals can be a set of two reception signals, or it can be a set of three or more reception signals.

[0034] The position estimation unit 125 estimates the position of the signal source based on the determined reception time and positional displacement relationship. When the signal receiver is placed at a different position due to the rotation of the main lobe, the reception time of the signal from the signal source will be different. This embodiment utilizes the fact that signals are received at different times at different positions, and estimates the position of the signal source based on the relationship between the reception time and the displacement of the reception position.

[0035] In one embodiment, the reception time and positional displacement relationship determination unit 124 can determine at least one of an intra-cycle relationship, which is determined by using the fact that the main lobe of the signal source is received by multiple signal receivers at different positions and different times while it makes one rotation, and an inter-cycle relationship, which is determined by using the fact that after one moving signal receiver receives a signal, the moving signal receiver receives the signal again at a different position while the main lobe is rotating, at the timing when the main lobe reaches the signal receiver in the next or subsequent rotation.

[0036] The same-cycle relationship is determined for a pair of signals of the same cycle of a rotating main lobe received by two different receivers, i.e., two signals received by two different receivers while the main lobe rotates 360 degrees, based on the rotational angular velocity of the main lobe, the difference in reception times of the same-cycle signals, the positions of the receivers at the reception times of the same-cycle signals, and the position of the signal source that generated the main lobe. The different-cycle relationship is determined for a pair of signals of two different cycles of a rotating main lobe received by the same moving receiver, i.e., a signal received while the main lobe rotates 360 degrees and a signal received during the next 360 degrees or the next or subsequent 360 degrees of rotation, based on the rotational angular velocity of the main lobe, the difference in reception times of the two different cycles of the signals, the positions of the receivers at the times when the two different cycles of the signals were received, and the position of the signal source that generated the main lobe.

[0037] The position estimation unit 125 may estimate the position of the signal source based on only one of the determined intra-period relationship and the determined inter-period relationship, or may use both.

[0038] An example of an equation showing the same period relationship is shown in Equation 1 below, and an example of an equation showing the different period relationship is shown in Equation 2 below.

[0039]

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[0040] where: t i,j : The time when the i-th receiver received the j-th signal p i,j : the position vector of the i-th receiver when the j-th signal is received p e : Position vector of the signal source ω: Rotation angular velocity vector of the signal source's main lobe is.

[0041] p i,j and p e As mentioned above, represents the position vector of the receiver and the signal source, and here it is expressed by latitude and longitude, but it may also be expressed by a coordinate system using altitude in addition to latitude and longitude, or any other coordinate system may be used.

[0042] Equation 1 is an example of a relational expression showing the same rotational relationship, and is a relational expression that expresses, as a set, two signals received by two different receivers while the rotating main lobe generated by the signal source rotates 360 degrees. The position of the receiver at the time the signal is received can be acquired by the position information acquisition device 114 of the signal receiver 11. When the position of the signal source is expressed as a position vector using latitude and longitude, the unknowns in Equation 1 are the rotational angular velocity vector ω of the main lobe of the signal source, and the latitude and longitude components of the vector of the signal source. Therefore, the position of the signal source can be identified by obtaining three or more relational expressions based on Equation 1 and solving the equations.

[0043] For example, if there are four receivers, the times received by the first to fourth receivers are denoted as t 0,0 ~t 3,0 and each position is p 0,0 ~p 3,0 Then, the time t received by the first receiver 0,1 and the position p of the first receiver at that time 0,0and the reception times t of the second to fourth receivers. 1,0 ~t 3,0 and position p 1,0 ~p 3,0 Three relational expressions can be formulated. The first to fourth reception times t 0,0 ~t 3,0 and each position p 0,0 ~p 3,0 is known, the rotation angular velocity vector ω of the main lobe of the signal source and the latitude and longitude components of the vector of the signal source can be determined.

[0044] Equation 2 is an example of a relational expression showing the inter-frequency relationship, and is a relational expression expressed as a pair of two signals received at different revolutions when a signal is received by one moving receiver every time the rotating main lobe generated by the signal source rotates 360 degrees. For example, by pairing the received signals at the first and second revolutions of the main lobe, the received signals at the first and third revolutions, and the received signals at the first and fourth revolutions, three inter-frequency relationship relational expressions can be obtained. Since the receiver moves, the time of each reception (t 0,0 ~t 0,3 ) at the receiving position (p 0,0 ~p 0,3 ) are also different. When the position of a signal source is expressed as a position vector using latitude and longitude, similar to Equation 1, there are three unknowns: the rotation angular velocity vector ω of the main lobe of the signal source, and the latitude and longitude components of the vector of the signal source. Therefore, the position of the signal source can be identified by obtaining three or more relational expressions based on Equation 2 and solving the equations.

[0045] Furthermore, if the rotational angular velocity of the main lobe of a signal source is known, the location of the signal source can be identified by obtaining two or more relational equations. If the location of the signal source is identified using altitude in addition to latitude and longitude, the number of unknowns becomes four. In this case, the location of the signal source can be identified by obtaining four or more relational equations. Furthermore, if the combined number of intra-cycle relational equations and inter-cycle relational equations is equal to or greater than the number of unknowns, the location of the signal source can be identified by solving the equations.

[0046] The position estimation unit 125 may estimate the position of the signal source using maximum likelihood estimation based on the reception times and the plurality of intra-circumferential relational expressions and the plurality of inter-circumferential relational expressions determined by the positional displacement relation determination unit 124. If the intra-circumferential relational expressions and the inter-circumferential relational expressions are obtained over a plurality of rotations (j times) using a plurality (i) of receivers, a large number of intra-circumferential relational expressions and inter-circumferential relational expressions can be obtained. The maximum likelihood estimation uses Equation 5, which is defined by the following Equations 3 and 4, as an objective function, and by minimizing the absolute value of the objective function, the position of the signal source (p e ) and the rotation angular velocity (ω) of the main lobe can be estimated.

[0047]

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[0048] By using maximum likelihood estimation, it is possible to estimate the location of a signal source more accurately than when estimating the location of a signal source based on three relational expressions for three unknowns.

[0049] 3 shows the flow of processing operations of the estimation system 1 in this embodiment. First, signals transmitted from a signal generating source that generates a rotating main lobe are received at different times at different positions (S301). Signals are received at different times at different positions so that two received signals received at different times at different positions are grouped into pairs, and multiple pairs can be created.

[0050] Next, for the pair of received signals, the reception time and positional displacement relationship due to the rotation of the main lobe are determined based on the rotation angular velocity of the main lobe, the reception time difference between the two received signals, the position of the receiver at the time the two received signals were received, and the position of the signal source that generated the main lobe at the time the two received signals were received (S302). The reception time and positional displacement relationship can be either an in-cycle relationship or an inter-cycle relationship, or a combination of these.

[0051] The position of the signal source is estimated based on the reception time and the positional displacement relationship determined in S302 (S304). The position may be estimated by obtaining a relational expression with more than the unknowns and solving the equation based on the relational expression, or by using maximum likelihood estimation.

[0052] Fig. 4 shows estimated values ​​obtained by an experiment using this embodiment. 400 indicates the actual position of the signal source, and 410 to 413 are positions where a single moving receiver received a signal from the signal source. Based on these four receiving positions and using the inter-frequency relational equation (Equation 2), the estimated position of the signal source is 401. It can be seen that an estimated position close to the actual signal position was obtained.

[0053] 5 shows an example of the results of estimating the position of a signal source using Equation 5, which is defined by Equations 3 and 4, obtained from a plurality of intra-period relational expressions (Equation 1) and inter-period relational expressions (Equation 2) in this embodiment. 500 is the actual position of the signal source, and the lighter the grayscale color, the smaller the absolute value of the objective function. In other words, the position 501, which has the lightest color, is estimated to be the position of the signal source.

[0054] In the processes or operations described above, the processes or operations can be freely changed as long as no inconsistencies in the processes or operations occur, such as the use of data that should not yet be available in a certain step. Furthermore, the embodiments described above are merely examples for explaining the present invention, and the present invention is not limited to these examples. The present invention can be embodied in various forms without departing from the spirit of the invention. [Explanation of symbols]

[0055] 1: Estimation system, 2: Earth station, 10: Signal generator, 11: Signal receiver, 12: Earth station, 13: Satellite orbit, 14: Main lobe, 110: Control device, 111: Storage device, 112: Communication transceiver, 113: Receiver, 114: Position information acquisition device, 120: Control device, 121: Storage device, 122: Communication transceiver, 123: Estimation device, 124: Position displacement relationship determination unit, 125: Position estimation unit

Claims

1. An estimation device for estimating a position of a signal source that generates a signal while rotating the direction of a main lobe, comprising: a reception time and positional displacement relationship determiner that determines, for a plurality of sets of received signals of the rotating main lobe signal received at different positions and different times, a reception time and positional displacement relationship caused by main lobe rotation based on a rotation angular velocity of the main lobe, a reception time difference between the plurality of received signals, a position of a receiver at the time the plurality of received signals were received, and a position of a signal generation source that generated the main lobe at the time the plurality of received signals were received, wherein the reception time and positional displacement relationship is determined for each of the plurality of sets; an estimation unit that estimates a rotation angular velocity of the main lobe and a position of a signal source based on the reception times and positional displacement relationships determined for the plurality of pairs; An estimation device comprising:

2. The reception time and positional displacement relationship determination unit For a set of two signals of the same rotation of the rotating main lobe received by two different receivers, an in-rotation relationship is based on the rotation angular velocity of the main lobe, the reception time difference of the signals of the same rotation, the positions of the receivers at the reception times of the signals of the same rotation, and the position of a signal source that generated the main lobe; and For a set of signals of two different frequencies of the rotating main lobe received by the same moving receiver, determine at least one of the inter-frequency relationships based on the rotational angular velocity of the main lobe, the reception time difference of the signals of the two different frequencies, the position of the receiver at the time when the signals of the two different frequencies were received, and the position of a signal source that generated the main lobe; the estimation unit estimates a position of a signal source based on the determined relationship. The estimation device according to claim 1 .

3. The estimation device according to claim 2 , wherein the same-period relationship is a relationship expressed by the following formula 1, and the different-period relationship is a relationship expressed by the following formula 2. [Equation 1] [Equation 2] where: t i,j : the time when the i-th receiver receives the j-th signal p i,j : Position vector of the i-th receiver when receiving the j-th signal p e : Position vector of the signal source ω: Rotation angular velocity vector of the signal source's main lobe is.

4. 3. The estimation device according to claim 2, wherein the estimation unit determines the same or different frequency relationships for a plurality of pairs, and determines the different frequency relationships for a plurality of pairs, and estimates the position of a signal source using maximum likelihood estimation based on the determined same or different frequency relationships.

5. The maximum likelihood estimation uses Equation 5, which is defined by the following Equations 3 and 4, as an objective function, and by minimizing the absolute value of the objective function, the position of the signal source (p e 5. The estimation device according to claim 4, wherein the rotational angular velocity (ω) of the main lobe is estimated. [Equation 3] [Equation 4] [Equation 5]

6. An earth station including an estimator according to claim 1.

7. The estimation device according to claim 1 ; one or more receivers for receiving signals from a signal generating source that generates signals while rotating the direction of a main lobe; An estimation system comprising:

8. The estimation system of claim 7 , wherein the receiver is a satellite.

9. 1. A method for estimating the position of a signal source that generates a signal while rotating the direction of a main lobe, comprising: For a plurality of sets of received signals of the rotating main lobe signal received at different positions and different times, a reception time and positional displacement relationship due to main lobe rotation is determined based on the rotation angular velocity of the main lobe, a reception time difference of the plurality of received signals, a position of a receiver at the time of receiving the plurality of received signals, and a position of a signal generation source that generated the main lobe at the time of receiving the plurality of received signals, and the reception time and positional displacement relationship is determined for each of the plurality of sets; estimating a rotation angular velocity of the main lobe and a position of a signal source based on the reception times and positional displacement relationships determined for the plurality of pairs; method.

10. A program for causing one or more computers to carry out the method according to claim 9.

11. An estimation device for estimating a position of a signal source that generates a signal while rotating the direction of a main lobe, comprising: a means for determining a reception time and positional displacement relationship that determines a reception time and positional displacement relationship due to main lobe rotation for a plurality of sets of received signals of the rotating main lobe signal received at different positions and different times, based on the rotation angular velocity of the main lobe, a reception time difference between the plurality of received signals, the position of a receiver at the time of receiving the plurality of received signals, and the position of a signal generating source that generated the main lobe at the time of receiving the plurality of received signals, wherein the reception time and positional displacement relationship is determined for each of the plurality of sets; means for estimating the rotation angular velocity of the main lobe and the position of a signal source based on the reception times and positional displacement relationships determined for the plurality of pairs; An estimation device comprising:

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