Moving body monitoring device

Abstract

To suppress a variation in a detection position of a moving body wherever a movable body is positioned.SOLUTION: A moving body monitoring device includes: an individual calculation position calculation part 16 for calculating an individual calculation position Pj being a position having a signal transmitted by a moving body 4 on the basis of the position and receiving time of each receiving station 3 included in a receiving station combination for each receiving station combination being the combination of the positioning minimum number of the receiving station 3 for receiving the signal transmitted by the moving body 4; a moving body position candidate extraction part 17 for extracting a moving body position candidate being an individual calculation position satisfying decided adjacent distance conditions determined using an adjacent distance set at each individual calculation position being a first decided number of adjacent distance sets including the minimum and continuously arranged in an adjacent distance row arranged in small order for each individual calculation position Pj on the basis of an adjacent distance being a distance with another individual calculation position Pk at the individual calculation position Pj; and a moving body position calculation part 18 for calculating a moving body position PP being a position of a moving body on the basis of the moving body position candidate.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to a mobile object monitoring device that measures and monitors the position of a mobile object such as an aircraft. [Background technology]

[0002] A multilateration system is a system for measuring the position of aircraft on the airport surface or flying near the airport. In a multilateration system, at least eight receiving stations, and up to 40 in some cases, are placed around the airport runway. In a multilateration system, signals from transponders installed on aircraft are received. Each receiving station receives the radio waves, and the aircraft's position is calculated using the difference in reception time at each receiving station and the position of each receiving station. In a multilateration system, when there are many receiving stations, a large number of detected position solutions are generated depending on the number of combinations of receiving stations. Therefore, if one or more solutions are significantly off-position due to multipath or other reasons, the detected position tends to vary when calculating the center of gravity position from the positions of the multiple solutions.

[0003] Furthermore, since the system is designed on the assumption that the target aircraft will pass through the centerline of the route, such as a taxiway or runway, if the detection position varies, the target display on the display device will deviate from the centerline of the route, which creates an uncomfortable feeling for the controller monitoring the aircraft, posing a problem when controlling a large number of aircraft.

[0004] One method is to store the centerline information of the route in a database in advance in the target processor, calculate the vertical distance to the centerline from a large number of detected position solutions that are generated in proportion to the number of combinations of receiving stations, and identify the target's position coordinates by weighting each detected position solution calculated according to this vertical distance (for example, Patent Document 1). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent Publication No. 2011-21978 Summary of the Invention [Problem to be solved by the invention]

[0006] The method of Patent Document 1 can only be used in places where centerline information is available, and it requires a lot of effort to input and maintain the centerline information. An object of the present disclosure is to provide a moving object monitoring device that can reduce variations in the detected position of a moving object, regardless of where the moving object is located. [Means for solving the problem]

[0007] The mobile object monitoring device according to the present disclosure includes a position data storage unit that stores the positions of a plurality of receiving stations that receive a signal transmitted by a mobile object; a receiving time acquisition unit that acquires the reception time, which is the time when the receiving station received the signal; a receiving station combination generation unit that generates a number of receiving station combinations, which are combinations of the minimum number of receiving stations that received the signal, for positioning purposes, which is three if the mobile object is on the Earth's surface and four if the mobile object is in the air, the number of combinations being the smaller of a predetermined number or the number of all possible combinations; and a unit that calculates, for each receiving station combination, an individual calculated position, which is the position where the mobile object transmitted the signal, and where each receiving station included in the receiving station combination receives the signal at the reception time, based on the position and reception time of each receiving station included in the receiving station combination. the individual calculation position calculation unit extracts mobile body position candidates, which are individual calculation positions that satisfy a predetermined adjacent distance condition determined using an adjacent distance set of each individual calculation position, which is a set of a predetermined first number of adjacent distances that are consecutively arranged, including the smallest, in a sequence of adjacent distances arranged in ascending order for each individual calculation position, based on the adjacent distance, which is the distance between each individual calculation position and another individual calculation position, or that satisfy a predetermined adjacent set condition determined using an adjacent individual calculation position set of each individual calculation position, which is a set of individual calculation positions that have any of the adjacent distances included in the adjacent distance set; and a mobile body position calculation unit calculates the mobile body position, which is the position of the mobile body, based on the mobile body position candidates. [Effects of the Invention]

[0008] According to the moving object monitoring device according to the present disclosure, it is possible to reduce the variation in the detected position of a moving object, regardless of where the moving object is located. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a diagram illustrating a configuration of an aircraft monitoring system including an aircraft monitoring device according to a first embodiment. [Figure 2] 1 is a block diagram illustrating the functional configuration of an aircraft monitoring device according to a first embodiment. [Figure 3] FIG. 10 is a diagram showing how an aircraft position is determined from the difference in reception times between a pair of receiving stations in an aircraft monitoring device. [Figure 4] 4 is a flowchart illustrating the overall operation of the aircraft monitoring device according to the first embodiment. [Figure 5] 5 is a flowchart illustrating processing by which the aircraft monitoring device according to the first embodiment receives response signal reception data, finds the aircraft position, and updates the trajectory. [Figure 6] 4 is a flowchart illustrating a process in which the aircraft monitoring device according to the first embodiment obtains an aircraft position and updates a trajectory. [Figure 7] 5 is a flowchart illustrating a process in which an aircraft position candidate extraction unit included in the aircraft monitoring device according to the first embodiment extracts aircraft position candidates from a plot. [Figure 8] 3 is a diagram showing a plot used to explain an aircraft position determined by the aircraft monitoring device according to the first embodiment. FIG. [Figure 9] 4 is a diagram showing aircraft position candidates and aircraft positions determined from plots by the aircraft monitoring device according to the first embodiment. FIG. [Figure 10] FIG. 4 is a block diagram illustrating the functional configuration of an aircraft monitoring device according to a first modification of the first embodiment. [Figure 11]10 is a flowchart illustrating a process in which an aircraft monitoring device according to a first modification of the first embodiment obtains an aircraft position and updates a trajectory. [Figure 12] 10 is a flowchart illustrating a process in which an aircraft position candidate extraction unit included in the aircraft monitoring device according to the first modification of the first embodiment extracts aircraft position candidates from a plot. [Figure 13] 10 is the first half of a flowchart illustrating a process in which an aircraft position calculation unit included in an aircraft monitoring device according to a first modification of the first embodiment determines an aircraft position from aircraft position candidates. [Figure 14] 10 is the second half of a flowchart illustrating the process in which an aircraft position calculation unit included in the aircraft monitoring device according to the first modification of the first embodiment determines an aircraft position from aircraft position candidates. [Figure 15] FIG. 10 is a diagram showing aircraft position candidates and aircraft positions determined from plots by an aircraft monitoring device according to a first modification of the first embodiment. [Figure 16] FIG. 10 is a block diagram illustrating the functional configuration of an aircraft monitoring device according to a second modification of the first embodiment. [Figure 17] 10 is a flowchart illustrating a process in which an aircraft monitoring device according to a second modification of the first embodiment obtains an aircraft position and updates a trajectory. [Figure 18] 10 is a flowchart illustrating a process in which an aircraft position candidate extraction unit included in an aircraft monitoring device according to a second modification of the first embodiment extracts aircraft position candidates from a plot. [Figure 19] FIG. 10 is a block diagram illustrating the functional configuration of an aircraft monitoring device according to a second embodiment. [Figure 20] 10 is a diagram showing an example of a plot illustrating the operation of an aircraft position candidate extraction unit included in the aircraft monitoring device according to the second embodiment. FIG. [Figure 21] 10 is a diagram illustrating an example of an ordering number, an adjacent order, an order distance, an order distance index, and an aircraft position candidate used by an aircraft position candidate extraction unit included in an aircraft monitoring device according to a second embodiment. FIG. [Figure 22]10 is a flowchart illustrating a process in which an aircraft monitoring device according to a second embodiment obtains an aircraft position and updates a trajectory. [Figure 23] 10 is a flowchart illustrating a process in which an aircraft position candidate extraction unit included in the aircraft monitoring device according to the second embodiment extracts aircraft position candidates from a plot. [Figure 24] FIG. 10 is a block diagram illustrating the functional configuration of an aircraft monitoring device according to a third embodiment. [Figure 25] 10 is a flowchart illustrating a process in which an aircraft monitoring device according to a third embodiment obtains an aircraft position and updates a trajectory. [Figure 26] 10 is the first half of a flowchart illustrating a process in which an aircraft position candidate extraction unit included in an aircraft monitoring device according to a third embodiment extracts aircraft position candidates from a plot. [Figure 27] 10 is the second half of a flowchart illustrating the process of extracting aircraft position candidates from a plot by an aircraft position candidate extraction unit included in the aircraft monitoring device according to the third embodiment. [Figure 28] 10 is a diagram illustrating an example of a process in which an aircraft position candidate extraction unit included in an aircraft monitoring device according to a third embodiment extracts aircraft position candidates from a plot. FIG. [Figure 29] FIG. 10 is a block diagram illustrating the functional configuration of an aircraft monitoring device according to a fourth embodiment. [Figure 30] 10 is a diagram illustrating an example of an interior division ratio determined by an aircraft position integrating unit included in the aircraft monitoring device according to the fourth embodiment. FIG. [Figure 31] 10 is a flowchart illustrating the overall operation of the aircraft monitoring device according to the fourth embodiment. [Figure 32] 10 is a flowchart illustrating processing by an aircraft monitoring device according to a fourth embodiment to receive response signal reception data, determine the aircraft position, and update the trajectory. [Figure 33] 10 is a flowchart illustrating the process of updating a trajectory by an aircraft monitoring device according to a fourth embodiment, which determines an aircraft position based on a plot and a predicted aircraft position. [Figure 34]10 is a flowchart illustrating a process in which a second aircraft position candidate extraction unit included in the aircraft monitoring device according to the fourth embodiment extracts second aircraft position candidates from a plot. [Figure 35] 10 is a diagram showing aircraft position candidates and aircraft positions determined by an aircraft monitoring device according to a fourth embodiment when the speed or acceleration is high. FIG. [Figure 36] FIG. 10 is a diagram showing second aircraft position candidates and the aircraft position determined by the aircraft monitoring device according to the fourth embodiment when the speed and acceleration are low. [Figure 37] FIG. 10 is a diagram showing an aircraft position candidate, a second aircraft position candidate, and an aircraft position determined by an aircraft monitoring device according to a fourth embodiment when the speed and acceleration are intermediate values. [Figure 38] FIG. 13 is a block diagram illustrating the functional configuration of an aircraft monitoring device according to a first modified example of the fourth embodiment. [Figure 39] 13 is a diagram illustrating an example of an interior division ratio determined by an aircraft position integrating unit included in an aircraft monitoring device according to a first modified example of the fourth embodiment. FIG. [Figure 40] FIG. 10 is a block diagram illustrating the functional configuration of an aircraft monitoring device according to a fifth embodiment. [Figure 41] 10 is a flowchart illustrating the process of updating a trajectory by an aircraft monitoring device according to a fifth embodiment, which determines an aircraft position based on a plot and a predicted aircraft position. [Figure 42] 13 is a flowchart illustrating a process in which an aircraft position candidate extraction unit included in the aircraft monitoring device according to the fifth embodiment extracts aircraft position candidates from a plot. [Figure 43] 13 is a flowchart illustrating a process in which a second aircraft position candidate extraction unit included in the aircraft monitoring device according to the fifth embodiment extracts second aircraft position candidates from a plot. [Figure 44] 13 is a diagram showing aircraft position candidates and aircraft positions determined by an aircraft monitoring device according to a fifth embodiment when the speed or acceleration is high. FIG. [Figure 45] FIG. 13 is a block diagram illustrating the functional configuration of an aircraft monitoring device according to a sixth embodiment. [Figure 46] 13 is a diagram illustrating an example of an interior division ratio determined by an aircraft position integrating unit included in the aircraft monitoring device according to the sixth embodiment. FIG. [Figure 47] 13 is a flowchart illustrating the overall operation of the aircraft monitoring device according to the sixth embodiment. [Figure 48] 13 is a flowchart illustrating the process in which an aircraft monitoring device according to a sixth embodiment receives response signal reception data, finds the aircraft position, and updates the trajectory. [Figure 49] 13 is a flowchart illustrating the process of updating a trajectory by an aircraft monitoring device according to a sixth embodiment, which determines an aircraft position based on a plot and a predicted aircraft position. DETAILED DESCRIPTION OF THE INVENTION

[0010] Embodiment 1 1 is a diagram illustrating the configuration of an aircraft monitoring system including an aircraft monitoring device according to embodiment 1. The aircraft monitoring system 50 includes an aircraft monitoring device 1, a transmitting station 2, and a plurality of (N) receiving stations 31 to 33. N The system mainly comprises an aircraft 4 to be monitored and a ground network 5. The aircraft monitoring device 1 is a device for determining the position of the aircraft 4 and monitoring the aircraft 4. The transmitting station 2 is a wireless communication station for transmitting an interrogation signal to the aircraft 4 by radio. The receiving stations 31 to 3 N is a radio communication station that receives a response signal transmitted by radio from an aircraft 4 that has received an interrogation signal. j The response signal is a signal transmitted by an aircraft 4, which is a moving object. The ground network 5 includes an aircraft monitoring device 1, a transmitting station 2, and receiving stations 31 to 3. N It is a wired communication network laid on the ground that enables communication between

[0011] The transmitting station 2 transmits an interrogation signal radio wave at a predetermined interval (for example, about 0.4 to 0.6 seconds) into the space that is the target of monitoring by the aircraft monitoring device 1. The aircraft 4 that receives the interrogation signal transmits a response signal that includes an ID (Identification) that identifies the aircraft 4. The ID that identifies the aircraft 4 is called the aircraft ID. The receiving station 3 that receives the response signal j transmits the response signal reception data including the reception time and the aircraft ID to the aircraft monitoring device 1 via the ground network 5.

[0012] The aircraft monitoring device 1 distributes the response signal reception data for each aircraft ID. The aircraft monitoring device 1 then selects the response signal reception data from the receiving station 3 from the response signal reception data distributed for each aircraft ID. j The aircraft monitoring device 1 extracts the reception time of the two receiving stations 3. j The difference in reception time between the two receiving stations j At least two sets of positions are used to calculate the position of the aircraft 4. The aircraft monitoring device 1 displays the calculated position of the aircraft 4 as a trajectory on a screen or the like and presents it to the operator.

[0013] The functional configuration of the aircraft monitoring device 1 will be described with reference to Fig. 2. Fig. 2 is a block diagram illustrating the functional configuration of the aircraft monitoring device according to embodiment 1. The aircraft monitoring device 1 has a data storage unit 11, a network communication unit 12, a response signal reception data sorting unit 13, a reception time data generation unit 14, a receiving station combination generation unit 15, a plot calculation unit 16, an aircraft position candidate extraction unit 17, an aircraft position calculation unit 18, and a trajectory generation unit 19.

[0014] The data storage unit 11 calculates the position of the aircraft 4 and stores data necessary for generating a trajectory, as well as data on the calculated position and trajectory of the aircraft 4. The network communication unit 12 communicates with the transmitting station 2 and the receiving stations 31-3 via the ground network 5. N The response signal reception data distribution unit 13 communicates with the receiving stations 31 to 33. NThe response signal reception data transmitted by the receiving station 3 and received by the network communication unit 12 is sorted by aircraft ID. The reception time data generation unit 14 generates reception time data managed for each aircraft ID from the response signal reception data sorted for each aircraft ID. The reception time data generation unit 14 j is a reception time acquisition unit that acquires the reception time, which is the time when the response signal is received.

[0015] The receiving station combination generation unit 15 generates a predetermined number of combinations of three or four receiving stations (abbreviated as receiving station combinations) from the reception time data for each aircraft ID. When the aircraft 4 is on the Earth's surface, the position of the aircraft 4 can be calculated from the reception times and positions of three receiving stations. When the aircraft 4 is in the air, the position of the aircraft 4 can be calculated from the reception times and positions of four receiving stations. Three or four is called the minimum number of positions for positioning. A combination of receiving stations with the minimum number of positions for positioning is called a receiving station combination. The plot calculation unit 16 calculates the aircraft position from the positions and reception times of the receiving stations included in one receiving station combination. One aircraft position calculated by the plot calculation unit 16 for one receiving station combination is called a plot. The aircraft position candidate extraction unit 17 calculates the distance between the plot and other plots and extracts aircraft position candidates, which are plots excluding plots that are far from the others. The aircraft position calculation unit 18 calculates the aircraft position from the aircraft position candidates. The trajectory generating unit 19 generates a trajectory (also called a track) connecting aircraft positions calculated at adjacent times.

[0016] The plots are for each receiving station included in the receiving station combination. j is an individually calculated position, which is the position where the aircraft 4 transmitted the response signal and receives the response signal at the reception time included in the reception time data. The plot calculation unit 16 is an individually calculated position calculation unit that calculates an individually calculated position for each combination of receiving stations.

[0017] The data storage unit 11 stores receiving station positions 20, Earth surface data 21, number of combination calculations 22, response signal reception data 23, reception time data 24, calculation mode 25, receiving station combinations 26, upper limit number of receiving stations calculated for all combinations 27, plot 28, adjacent distance 29, ordered distance 30, adjacent distance index 31, top number 32, index upper limit value 33, aircraft position candidate 34, number of aircraft position candidate 35, aircraft position 36, and trajectory data 37. The receiving station positions 20 are stored in the data storage unit 11 for each receiving station 3. j The data storage unit 11 stores the positions of the plurality of receiving stations 3. j The position data storage unit stores the position of the object.

[0018] The earth's surface data 21 is data representing the earth's surface where an aircraft 4 may be present. The earth's surface data 21 is data that makes it possible to calculate the altitude of the earth's surface at a point specified by latitude and longitude, or by coordinates with a reference point as the origin of the coordinates. The earth's surface also includes the rooftops of structures on land or water. The combination calculation number 22 is the number of plots to calculate when the number of receiving stations that have received response signals is large. The integer stored in the combination calculation number 22 is represented by the variable Ncmb.

[0019] The response signal reception data 23 is transmitted to each receiving station 3 j The response signal reception data 23 is a table that manages the response signal reception data using the aircraft ID as a key. The response signal reception data 23 can easily search for response signal reception data with the same aircraft ID. The reception time data 24 is the time when the receiving station 3 receives the response signal. j The receiving station ID and receiving station 3 are IDs representing j The data is stored in pairs with the time of reception of the response signal at the aircraft ID. The reception time data 24 is stored for each aircraft ID by processing the response signal reception data 23 for each aircraft ID. The reception time data 24 for the same aircraft ID is stored in an array. The reception time data 24 is specified by an integer that indicates the storage position in the array.

[0020] The calculation mode 25 is data that stores how to calculate the position of an aircraft having an aircraft ID for each aircraft ID. The calculation mode is represented by the variable MD. The calculation mode MD takes on one of two values: "Earth's surface" or "Air". "Earth's surface" indicates that the aircraft 4 having the aircraft ID is located on the Earth's surface. "Air" indicates that the aircraft 4 is located in the air away from the Earth's surface. The receiving station combination 26 is data that stores, for each aircraft ID, a combination of the minimum number of reception time data 24 required for positioning.

[0021] The receiving station combination 26 is data (called receiving station combination data) that combines integers representing the storage positions of the reception time data 24 by the minimum number of positionings. Note that if the minimum number of positionings is three, the fourth integer in the receiving station combination data may be set to a value such as -1. The receiving station combination 26 can store the number (Ncmb) of receiving station combination data specified by the combination calculation number 22 for each aircraft ID. The total combination calculation receiving station upper limit number 27 is an integer that is compared with the number n of receiving station data 22 for the same aircraft ID to determine whether to generate receiving station combination data for all possible combinations or the number Ncmb. The total combination calculation receiving station upper limit number 27 stores the value m3 when the minimum number of positionings is three and the value m4 when the minimum number of positionings is four. The value m3 is determined to be a value that satisfies the following: m3 C3=m3*(m3-1)*(m3-2) / 6≦Ncmb (1) m3+1 C3=(m3+1)*m3*(m3-1) / 6>Ncmb (2) The value m4 is determined to satisfy the following: m4 C4=m4*(m4-1)*(m4-2)*(m4-3) / 24≦Ncmb (3) m4+1 C4=(m4+1)*m4*(m4-1)*(m4-2) / 24>Ncmb (4)

[0022] The number of combination data of receiving stations (Nb) generated by the calculation mode MD and the number of receiving stations n is as follows. Nb is called the number of combinations. The number of combinations Nb is either a fixed number (Ncmb) or the number of all possible combinations ( n C3 or n C4) whichever is smaller. (1) When the calculation mode MD is "Earth surface" If n≦m3, Nb= n C3 If n>m3, Nb=Ncmb (2) When the calculation mode MD is "Air" If n≦m4, Nb= n C4 If n>m4, Nb=Ncmb

[0023] The generated receiving station combination data is identified by an integer (called a combination number) that indicates the order in which it was generated. The generated receiving station combination data is stored at the position of the combination number in the array for each aircraft ID.

[0024] Plot 28 is data that stores data on the position of aircraft 4 calculated from the position of the receiving station specified in one receiving station combination data and the reception time. Plot 28 has a data area that can store Ncmb plots for each aircraft ID, and stores Nb plots that are actually calculated. Plot 28 is data that stores three-dimensional positions in an array for each aircraft ID. A plot calculated for a certain receiving station combination data is stored at the position of the combination number that represents the receiving station combination data in the array for each aircraft ID in plot 28. The combination number is also called the plot number.

[0025] The adjacent distance 29, the ordered distance 30, the adjacent distance index 31, the top number 32, and the index upper limit value 33 are data used by the aircraft position candidate extraction unit 17 to extract aircraft position candidates from all calculated plots. The adjacent distance 29 is data that stores the adjacent distance, which is the distance between two plots. The adjacent distance is calculated for all combinations of two plots and stored in the adjacent distance 29. The adjacent distance is the distance between each plot and other plots calculated for each plot. The ordered distance 30 is data that arranges the adjacent distances for each plot in ascending order. The adjacent distance index 31 is data that stores an index (adjacent distance index) calculated based on the adjacent distance for each plot. The adjacent distance index is the average value of a predetermined number of adjacent distances, starting from the smallest, for each plot. The top number 32 is data that stores an integer that represents the "predetermined number" for calculating the adjacent distance index. The "predetermined number," which is the top number, is represented by the variable m. The number of top plots m is 2 or more and is equal to or less than half the number of plots (Nb). It is desirable to set the number of top plots m to approximately the number of plots that are expected to be close to each other, even if there are many plots that are far from each other. The index upper limit value 33 is data that stores a constant to be compared with the adjacent distance index. The aircraft position candidate extraction unit 17 extracts plots whose adjacent distance index is equal to or less than the index upper limit value 33 as aircraft position candidates. Note that plots that are far from each other are plots that are likely to have been calculated using reception times that are affected by multipath, etc. The adjacent distance index makes it possible to order the plots.

[0026] The aircraft position candidate 34 is data excluding those plots that are far from the others among the calculated Nb plots. The aircraft position candidate 34 is represented as a one-dimensional array for each aircraft ID. The array indicating whether or not a plot is an aircraft position candidate 34 indicates whether the plot with that number is an aircraft position candidate based on the position value of the plot number. For example, if the position value of the plot number of the aircraft position candidate 34 is 1, it is an aircraft position candidate, and if it is 0, it is not an aircraft position candidate. The aircraft position 36 is the position of the aircraft 4 determined from multiple aircraft position candidates 34. The aircraft position 36 stores data on the latest and past aircraft positions over a predetermined period of time. The trajectory data 37 stores the latest and past calculated aircraft positions 36 and represents the trajectory connecting them. The data storage unit 11 is a mobile object position history storage unit that stores past aircraft positions over a predetermined period of time. The trajectory generation unit 19 is a mobile object trajectory generation unit that generates a mobile object trajectory connecting the aircraft positions stored in the data storage unit 11.

[0027] The receiving station combination generating unit 15 generates a combination of receiving stations with the minimum number of positions to be measured from the reception time data for each aircraft ID, with the number of receiving stations being equal to or less than the predetermined number Ncmb. When generating receiving station combination data for Ncmb, each receiving station 3 is determined based on the generated receiving station combination data. j are evenly distributed, and two receiving stations 3 j , 3 k If the minimum number of positioning stations is four, three more receiving stations 3 are generated. j , 3 k , 3 m The receiving station combination generation unit 15 generates receiving station combination data so that the combinations of Nb are evenly included. Including each element evenly means that the number of each element is either an integer obtained by rounding down the average number or an integer rounded up. If the average number does not have a fraction, the number of each element will be the average number. The receiving station combination generation unit 15 generates receiving station combination data for the number of combinations Nb.

[0028] The plot calculation unit 16 calculates one plot for one receiving station combination data. The plot calculation unit 16 stores the plot generated from the receiving station combination data in an array for each aircraft ID. Here, an example will be described in which the receiving station combination data specifies receiving stations (j, k, m, q). Receiving station 3 j , 3 k , 3 m , 3 q The plot calculated for the data of the receiving station combination is represented by the variable Pd(j,k,m,q) = (x,y,z). j , 3 k , 3 m , 3 q The positions of P R j =(xj,yj,zj), P R k =(xk,yk,zk), P R m =(xm,ym,zm), P R q =(xq, yq, zq). Receiving station 3 j , 3 k , 3 m , 3 q The reception times of the response signals are tj, tk, tm, and tp. The propagation speed of radio waves is c. Receiving station 3 j , 3 k , 3 m , 3 q From the difference in reception time at √((x-xk) 2 +(y-yk) 2 +(z-zk) 2 )-√((x-xj) 2 +(y-yj) 2 +(z-zj) 2 )=c*(tk-tj) (5) √((x-xm) 2 +(y-ym) 2 +(z-zm) 2 )-√((x-xj) 2 +(y-yj) 2 +(z-zj) 2 )=c*(tm-tj) (6) √((x-xq)2 +(y-yq) 2 +(z-zq) 2 )-√((x-xj) 2 +(y-yj) 2 +(z-zj) 2 )=c*(tp-tj) (7)

[0029] All of equations (5) to (7) represent hyperboloids. To prove that equation (5) is a hyperboloid, we can use the line segment P R j P R k Midpoint P of mid The UVW coordinate system is shown by converting it into the UVW coordinate system with the origin of the coordinate. R j P R k coincides with the U axis. The V axis exists on the XY plane. The axis perpendicular to the U and V axes is the W axis. Here, we define the following variables. (x0,y0,z0): Line segment P R j P R k Midpoint P of R mid Coordinates of. (xs,ys,zs): Vector P mid P k Ingredients. u0: Vector P R mid P R k Length. (u,v,w): Coordinate values ​​in the UVW coordinate system of the plot Pd. θ: Vector P R mid P R k The angle between the vector projected onto the XY plane and the X axis δ: Vector P R mid P R k The angle between this and the XY plane.

[0030] The following relation holds true: x0=(xj+xk) / 2 (8) y0=(yj+yk) / 2 (9) z0=(zj+zk) / 2 (10) xs=(xk-xj) / 2 (11) ys=(yk-yj) / 2 (12) zs=(zk-zj) / 2 (13) xj=x0-xs (14) yj=y0-ys (15) zj=y0-zs (16) xk=x0+xs (17) yk=y0+ys (18) zk=y0+zs (19)

[0031] Substituting equations (14) to (19) into equation (5) gives the following: √((x-x0-xs) 2 +(y-y0-ys) 2 +(z-z0-zs) 2 ) =√((x-x0+xs) 2 +(y-y0+ys) 2 +(z-z0+zs) 2 )+c*(tk-tj) (20)

[0032] In the UVW coordinate system, point P R mid is the origin of the coordinate system, and point P R k becomes (u0, 0, 0), and the point P R j becomes (-u0, 0, 0). The following relation holds: u0=√(xs 2 +ys 2 +zs 2 ) (twenty one) sinδ=zs / u0 (22) cosδ=√(xs 2 +ys 2 ) / u0 (23) sinθ=ys / √(xs 2 +ys 2 ) (twenty four) cosθ=xs / √(xs 2 +ys 2) (25) xs = u0 * cosδ * cosθ (26) ys = u0 * cosδ * sinθ (27) zs = u0 * sinδ (28)

[0033]

Number

[0034] When expressing Equation (20) in the UVW coordinate system, it becomes as follows. √((u - u0) 2 + v 2 + w 2 ) = √((u + u0) 2 + v 2 + w 2 ) + c * (tk - tj) (31) Squaring both sides of Equation (31) and transforming it, the following equation is obtained. -4 * u0 * u - c 2 *(tk - tj) 2 = 2 * c * (tk - tj) * √((u + u0) 2 + v 2 + w 2 ) (32) It can be seen from Equation (32) that when tk > tj, u < 0, and when tk < tj, u > 0.

[0035] Squaring both sides of Equation (32) and transforming it, the following equation is obtained. 4 * (4 * u0 2 - c 2 *(tk - tj) 2 ) * u 2 - 4 * c 2 *(tk - tj) 2 *(v 2 + w 2 ) =(4 * u0 2 - c 2 *(tk - tj) 2 ) * c 2 *(tk - tj) 2 (33)

[0036] Equation (33) can be transformed as follows by substituting the coefficients: Equations (34) to (36) are the standard forms of the equations of the hyperboloid. (u / a) 2 -(v / b) 2 -(w / b) 2 =1 (34) a=c*(tk-tj) / 2 (35) b=√(u0 2 -a 2 ) (36) The sign of u is determined by the sign of a. When a is positive, the aircraft position Pp is j Since the position is close to , we can transform equation (34) to obtain the following equation. u=-a*√(1+(v / b) 2 +(w / b) 2 ) (37)

[0037] In equation (36), in order for b to be calculated as a real number, the following equation must be satisfied. a <u0 (38) Equation (38) is the receiving station 3 j , 3 k The distance that radio waves can propagate during the time difference between the reception times at receiving station 3 is j , 3 k This means that the distance between the positions of

[0038] When the aircraft is in the air, the plot calculation unit 16 calculates the plot by simultaneously solving equations (5) to (7). When the aircraft is in the air, the plot is calculated as the intersection of three hyperboloids. When the aircraft is on the Earth's surface, the plot calculation unit 16 calculates the plot as the intersection of the hyperboloid of equations (5) to (6) with the surface represented by the Earth's surface data 21.

[0039] As shown in Figure 3, the plot is calculated as the intersection of three hyperboloids determined from the difference in reception time between three pairs of receiving stations obtained from four receiving stations. Figure 3 is a diagram showing how an aircraft monitoring device determines the position of an aircraft from the difference in reception time between pairs of receiving stations. In Figure 3, the intersection of the hyperboloid and the plane of the altitude at which the aircraft is located is shown by a dashed line.

[0040] The aircraft position candidate extraction unit 17 extracts aircraft position candidates 34 by referring to or calculating the adjacent distance 29, the ordered distance 30, the adjacent distance index 31, the top number 32, and the index upper limit value 33. The following variables are defined to explain the processing of the aircraft position candidate extraction unit 17. Nb: The number of plots calculated. m: The number of points for which the average is calculated from the smallest distance. m is stored in the top 32. P j : Plot number j. j =(xj,yj,zj) L(j, k):P j and P k The distance between j and k is called the neighbor distance. L(j, k) is stored in the neighbor distance 29. Lm(j,q):P j This is an array that lists the distances of the other plots in ascending order. q represents the order from smallest to largest. This is called the ordered distance. Lm(j,q) is stored in the ordered distance 30. Lav(j): Plot P j is the neighbor distance index. j Lav(j) is the average of the m smallest neighbor distances of the jth neighbors. Lav(j) is stored in the neighbor distance index 32. Lmax: a constant to be compared with the adjacent distance index Lav(j). Lmax is stored as the index upper limit value 33. Lmax is determined in advance. η(j): Plot P j is an array of data indicating whether or not the position of the aircraft is a candidate. If η(j)=1, plot P j is the aircraft position candidate. If η(j)=0, plot P jis not an aircraft position candidate. η(j) is stored as an aircraft position candidate 34. Nc: The number of aircraft position candidates. Nc is stored as the number of aircraft position candidates 35. P P : The aircraft position calculated by the aircraft position calculation unit 18. P P =(xp,yp,zp) is stored as the aircraft position 36.

[0041] The ordered distance Lm(j,q) is plotted as j The plot P is a sequence of adjacent distances L(j, k) arranged in ascending order. j The adjacent distance set of is defined as follows using Lm(j,q): LL(j): Plot P j A variable representing the set of neighbor distances. LL(j) = {Lm(j,q) | q is an integer between 1 and m} m is the number of plots P j m is the first number used to define the neighbor distance set LL(j). m is predetermined and stored as the top number 32. Plot P j The adjacent distance set LL(j) of the plot P j is a set of m consecutive ordered distances Lm(j,q) including the smallest one in the sequence Lm(j,q) of adjacent distances sorted in ascending order for each pair.

[0042] The aircraft position candidate extraction unit 17 calculates the adjacent distance L(j, k) using the formula below. L(j, k)=√((xj-xk) 2 +(yj-yk) 2 +(zj-zk) 2 ) (39) The aircraft position candidate extraction unit 17 references the adjacent distance L(j, k) to generate the ordered distance Lm(j, q). Lm(j, q) is an array in which L(j, k), k=1,...,Nb-1, are arranged in ascending order from the smallest to the largest. In Lm(j, q), j is the number of the plot P j The number of plots P is the number of plots P from the smallest to the largest. j And the following holds: Lm(j,1)≦Lm(j,2)≦…≦Lm(j, q)≦Lm(j, q+1)≦…≦Lm(j, Nb-1) (40)

[0043] The aircraft position candidate extraction unit 17 refers to the ordered distance Lm(j,q) and extracts the plot P j The adjacent distance index Lav(j) is calculated using the formula below. Lav(j)=(1 / m)*ΣLm(j,q) (41) In equation (41), Σ represents the sum of q=1,...,m.

[0044] The aircraft position candidate extraction unit 17 extracts the plot P j The adjacent distance index Lav(j) is compared with the index upper limit Lmax, and the plot P j Determine whether to consider the position of the aircraft as a candidate. If Lav(j)≦Lmax, η(j)=1 (42) If Lav(j)>Lmax, η(j)=0 (43)

[0045] Plot P j The neighbor distance index Lav(j) of the plot P j The neighbor distance index Lav(j) is calculated using the neighbor distance set LL(j). The equations (42) and (43) for the neighbor distance index Lav(j) are used to plot P j The equation (42) represents the adjacent distance condition determined by using the adjacent distance set LL(j). The equation (43) represents the case where the adjacent distance condition is satisfied. The equation (44) represents the case where the adjacent distance condition is not satisfied. The aircraft position candidate is the plot P that satisfies the adjacent distance condition. j The aircraft position candidate extraction unit 17 is a moving object position candidate extraction unit that extracts moving object position candidates that satisfy the adjacent distance condition.

[0046] The aircraft position calculation unit 18 calculates the aircraft position P P The aircraft position calculation unit 18 calculates the center of gravity of the aircraft position candidates to the aircraft position P PThe coordinates of the center of gravity of the aircraft position candidates are the average of the coordinates of the aircraft position candidates. The center of gravity of the aircraft position candidates is the position where the sum of the squares of the distances to each aircraft position candidate is the smallest. The aircraft position calculation unit 18 calculates the aircraft position P P The aircraft position calculation unit 18 calculates the coordinates (xp, yp, zp) of the aircraft 4. The aircraft position calculation unit 18 is a moving body position calculation unit that calculates the moving body position, which is the position of the moving body (aircraft 4), based on the moving body position candidates. The aircraft position calculated by the aircraft position calculation unit 18 is the detection position, which is the position where the aircraft monitoring device 1 detects the aircraft 4. xp=(1 / Nc)*Ση(j)*xj (44) yp=(1 / Nc)*Ση(j)*yj (45) zp=(1 / Nc)*Ση(j)*zj (46) In equations (44) to (46), Σ represents the sum of j=1, . . . , Nb.

[0047] The trajectory generation unit 19 calculates the latest calculated aircraft position P P The aircraft position P at each time is calculated by smoothing the aircraft position calculated in the past based on the calculated time. P The trajectory data 37 that smoothly connects the aircraft positions P is generated and stored in the data storage unit 11. In the smoothing process, a smoothing filter or the like is used to make the track smooth. The trajectory data 37 is displayed on a display device. The trajectory is calculated based on the most recently calculated aircraft position P P Alternatively, the symbol may be connected to the aircraft position calculated up to the last time.

[0048] 4 is a flowchart for explaining the overall operation of the aircraft monitoring device according to the first embodiment. Referring to FIG. 4, in step S01, the transmitting station 2 transmits an interrogation signal into space at a predetermined period. In step S02, each receiving station 3 j Each receiving station 3 receives a response signal transmitted from each aircraft 4 in response to the interrogation signal. jgenerates response signal reception data including the aircraft ID included in the response signal and the reception time of the response signal, and transmits the data to the aircraft monitoring device 1 via the ground network 5. In step S03, the aircraft monitoring device 1 receives the response signal reception data and determines the aircraft position P P After executing S03, return to S01.

[0049] 5, in S03, the aircraft monitoring device 1 receives the response signal reception data and determines the aircraft position P P 5 is a flowchart illustrating the process of receiving response signal reception data, determining the aircraft position, and updating the trajectory by the aircraft monitoring device according to the first embodiment. In step S11, the aircraft monitoring device 1 initializes a table for managing response signal reception data. The table manages the response signal reception data using the aircraft ID as a key. The table manages a set of response signal reception data having the same aircraft ID.

[0050] In step S12, the network communication unit 12 receives signal data from the ground network 5. In step S13, the response signal reception data allocation unit 13 checks whether the received signal data is response signal reception data. If the received signal data is not response signal reception data (NO in S13), the process returns to S12. If the received signal data is response signal reception data (YES in S13), the response signal reception data allocation unit 13 checks whether the aircraft ID of the response signal reception data exists as a key in the table in step S14. If the aircraft ID of the response signal reception data exists as a key in the table in S14 (YES in S14), the response signal reception data allocation unit 13 adds the response signal reception data to a set of response signal reception data managed by the aircraft ID included in the response signal reception data in step S15. If the aircraft ID included in the response signal reception data does not exist as a key in the table (NO in S14), a new aircraft ID is added to the table as a key in step S16, a set of response signal reception data using the new aircraft ID as a key is created, and the response signal reception data is added to the created set.

[0051] Next, in step S17, the response signal reception data sorting unit 13 checks whether the condition for terminating reception of the response signal reception data is met. The condition for terminating reception of the response signal reception data is, for example, when a predetermined time has elapsed since the transmitting station 2 transmitted the interrogation signal. If the condition for terminating reception of the response signal reception data is not met (NO in S17), the process returns to S12. If the condition for terminating reception of the response signal reception data is met (YES in S17), the process selects one aircraft ID in step S18. In step S19, the aircraft position and trajectory are calculated from the response signal reception data of the selected aircraft ID. In step S20, the process checks whether all aircraft IDs have been processed. If all aircraft IDs have been processed (YES in S20), the process ends. If there are aircraft IDs that have not yet been processed (NO in S20), the process returns to S19.

[0052] Referring to Figure 6, the process in S19 in which the aircraft monitoring device 1 determines the aircraft position and updates the trajectory will be described. Figure 6 is a flowchart illustrating the process in which the aircraft monitoring device according to embodiment 1 determines the aircraft position and updates the trajectory. In step S21, the reception time data generation unit 14 generates reception time data 24 from the response signal reception data 23 of the aircraft ID being processed, and acquires the calculation mode MD. In step S22, the reception station combination generation unit 15 determines the number Nb of reception station combination data to be generated according to the calculation mode MD and the number n of reception stations. In step S23, the reception station combination generation unit 15 generates Nb pieces of reception station combination data.

[0053] In step S24, the plot calculation unit 16 calculates the plot P for each receiving station combination data. j In step S25, the aircraft position candidate extraction unit 17 extracts the plot P P whose adjacent distance index calculated by averaging the minimum number of adjacent distances determined is equal to or less than the upper limit. j In step S26, the aircraft position calculation unit 18 extracts the aircraft position P P The aircraft position calculation unit 18 calculates the center of gravity of the aircraft position candidates to the aircraft position PP Let's say.

[0054] Referring to FIG. 7, the aircraft position candidate extraction unit 17 extracts the plot P j FIG. 7 is a flowchart illustrating a process of extracting aircraft position candidates from plots by the aircraft position candidate extraction unit of the aircraft monitoring device according to the first embodiment. In step S31, the aircraft position candidate extraction unit 17 extracts aircraft position candidates from two plots P j , P k In step S32, the aircraft position candidate extraction unit 17 calculates the adjacent distance L(j, k) between the plots P j For each, calculate the ordered distance Lm(j,q), which is an array in which the adjacent distances L(j,k) are arranged in ascending order. Here, in the ordered distance Lm(j,q), j is the number of points in the plot P j is the number, and q indicates the number from the smallest.

[0055] In step S33, the aircraft position candidate extraction unit 17 refers to the ordered distance Lm(j,q) and extracts the plot P j In step S34, j is set to 1. In step S35, it is checked whether Lav(j)≦Lmax is satisfied. If Lav(j)≦Lmax is satisfied (YES in S35), in step S36, the plot P j is the aircraft position candidate (η(j)=1). If Lav(j)≦Lmax is not established (NO in S35), in step S37, the plot P j is not an aircraft position candidate (η(j)=0).

[0056] In step S38, j=j+1 is set. In step S39, it is checked whether j≦Nb. If j≦Nb is not satisfied (NO in S39), all plots P j Since it has been checked whether j is an aircraft position candidate, the process ends. If j≦Nb (YES in S39), the process returns to S35.

[0057] An example in which the aircraft monitoring device 1 determines an aircraft position candidate and an aircraft position from a plot will be described using Figures 8 and 9. The case in which the aircraft is on the Earth's surface will be described. Figure 8 is a diagram showing plots used to explain the aircraft position determined by the aircraft monitoring device according to embodiment 1. In the figure, vertical and horizontal lines are drawn at equal intervals. In Figure 8, plots 90 are drawn as white circles. An aircraft position 91 calculated as the center of gravity of all plots 90 using a conventional method is indicated by a cross (x). The aircraft's trajectory 92 is indicated by a solid line. In Figure 8, the aircraft position (cross) is determined at a position away from a line 93 extending the trajectory.

[0058] FIG. 9 is a diagram showing aircraft position candidates and aircraft positions determined from plots by the aircraft monitoring device according to the first embodiment. In FIG. 9, m=9, and when the line spacing is 1, the index upper limit value Lmax=1.4. In FIG. 9, plots 90 extracted as aircraft position candidates are indicated by black circles. Plots 90 not extracted as aircraft position candidates are indicated by white circles. An aircraft position 94 determined as the center of gravity of the aircraft position candidates is indicated by a diamond (◇). The aircraft monitoring device 1 can determine the aircraft position at a position close to a line 93 extending the trajectory.

[0059] The distance between the aircraft position 94 and the plots 90 that were not extracted as aircraft position candidates is greater than the distance between the aircraft position 94 and the plots 90 that were extracted as aircraft position candidates. The aircraft position 94 is calculated excluding the distant plots 90, so it can be calculated close to the true position. The extent to which the distant plots 90 are separated depends on random factors such as multipath and processing delay, so if the aircraft position 94 is calculated including the distant plots 90, the aircraft position 94 will change significantly each time it is calculated, resulting in a large variance. In contrast, the aircraft position 94 calculated by the aircraft monitoring device 1 can be calculated to be close to the true position with reduced variance.

[0060] The aircraft monitoring device 1 transmits a response signal from the aircraft 4 to each receiving station 3. j The time of reception and each receiving station 3 jBy using this position data, the aircraft position can be determined with reduced variation no matter where the aircraft 4 is located. The aircraft's trajectory can also be made to be a natural curve.

[0061] The aircraft monitoring device 1 uses each plot P as an adjacent distance indicator. j The average of the m smallest neighbor distances is used for each plot P j The weighted average of the m smallest neighbor distances may be used as the neighbor distance index. The plot P j The adjacent distance condition may be a condition that does not use an adjacent distance index.

[0062] The aircraft monitoring device 1 determines the position of the center of gravity (average) of the aircraft position candidates as the aircraft position. The position of the center of gravity of the aircraft position candidates is the position where the sum of the squares of the distances to the aircraft position candidates is the smallest. The position where the sum of the distances (which are always positive) to the aircraft position candidates is the smallest may also be determined as the aircraft position. If the aircraft is on the Earth's surface, the center of a circle with the smallest radius that includes all the aircraft position candidates may also be determined as the aircraft position. If the aircraft is in the air, the center of a sphere with the smallest radius that includes all the aircraft position candidates may also be determined as the aircraft position. The aircraft position can be determined based on the aircraft position candidates.

[0063] First variant. The first modified example is a modification of the first embodiment in the following three respects. (a) The adjacent distance index is calculated by a weighted average. (a) Plots having adjacent distance indices whose ratios of the smallest adjacent distance indices to the average of a predetermined number of adjacent distance indices are equal to or less than an upper limit are also extracted as aircraft position candidates. (c) If the aircraft is on the Earth's surface, the center of the smallest circle that encompasses all aircraft position candidates is calculated as the aircraft position, and if the aircraft is in the air, the center of the smallest sphere that encompasses all aircraft position candidates is calculated as the aircraft position.

[0064] The functional configuration of an aircraft monitoring device 1A according to a first modified example of the first embodiment will be described with reference to Fig. 10. Fig. 10 is a block diagram illustrating the functional configuration of an aircraft monitoring device according to a first modified example of the first embodiment. Regarding Fig. 10, differences from Fig. 2 in the case of the first embodiment will be described. Compared with the aircraft monitoring device 1, the aircraft monitoring device 1A has a modified data storage unit 11A, an aircraft position candidate extraction unit 17A, and an aircraft position calculation unit 18A.

[0065] The data storage unit 11A also has a weighting coefficient 38, a reference adjacent distance index 39, a second highest number 40, a ratio to the reference 41, an upper ratio limit 42, a vertex position 43, a minimum radius 44, and a distance to the center 45. The weighting coefficient 38 relates to the change of (A). The reference adjacent distance index 39, the second highest number 40, the ratio to the reference 41, and the upper ratio limit 42 relate to the change of (B). The vertex position 43, the minimum radius 44, and the distance to the center 45 relate to the change of (C).

[0066] Define the following variables to represent the newly added data. ξq: The weighting factor used to calculate the weighted neighbor distance index Lav(j). It is stored as the weighting factor 38. L h : The average of a predetermined number of neighbor distance indices Lav(j) from the smallest. This is called the reference neighbor distance index. It is stored as the reference neighbor distance index 39. h:L h h is the number of neighbor distance indices Lav(j) used to calculate the reference neighbor distance index L. h is the second number used to calculate β(j): Adjacent distance index L based on adjacent distance index Lav(j) h This is the value divided by . It is called the reference ratio. It is stored as the reference ratio 41. βmax: a constant to be compared with the reference ratio β(j). This is called the upper limit of the ratio. It is stored as the upper limit of the ratio 42. H=(a,b,c,d):Aircraft position P P Plot P used to determine jIt is an array of numbers. It is called a vertex array. Two plots P j At aircraft position P P When determining the plot, set c=d=-1. j At aircraft position P P When determining the vertex position, set d=-1. The vertex position is stored as 43. rmin: Plot P specified by vertex position H j This is the radius of the circle or sphere that passes through. It is called the minimum radius. It is stored as the minimum radius 44. L x (j): Plot P specified by vertex position H j Plot the center of a circle or sphere that passes through P j This is the distance between the center and the center. It is stored as 45.

[0067] The aircraft position candidate extraction unit 17A refers to the ordered distance Lm(j,q) and the weighting coefficient ξq to generate the plot P j The adjacent distance index Lav(j) is calculated using the formula below. Lav(j)=Σξq*Lm(j,q) (47) In equations (47) and (48), Σ represents the sum of q=1,...,m.

[0068] The weighting coefficients ξq are determined so that their sum is 1, as shown below. Σξq=1 (48) 0≦ξq≦1 (49) The weighting coefficient ξq is j is a first weighting coefficient determined based on the number (q) of each Lm(j,q) included in the adjacent distance set LL(j) from the smallest in the adjacent distance set LL(j). Note that the weighting coefficient ξq may be determined as ξq = 1 / m regardless of q. In this case, equation (47) also calculates the sum of the products of the first weighting coefficient ξq and the adjacent distance Lm(j,q).

[0069] The aircraft position candidate extraction unit 17A uses the reference adjacent distance index L h is calculated using the formula below. Lh =(1 / h)*ΣLav(j) (50) In equation (50), Σ represents the sum of j = 1, ..., h. Equation (50) calculates the average of the smallest to second highest number (h) of adjacent distance indices Lav(j) as the reference adjacent distance index L h This means that it is calculated as The aircraft position candidate extraction unit 17A calculates the ratio β(j) to the reference using the following formula. β(j)=Lav(j) / L h (51)

[0070] The aircraft position candidate extraction unit 17A extracts the aircraft position candidate from the plot P j The adjacent distance index Lav(j) is compared with the index upper limit value Lmax, and the ratio β(j) is compared with the ratio upper limit value βmax, and the plot P j Determine whether to consider the position of the aircraft as a candidate. If Lav(j)≦Lmax or β(j)≦βmax, then η(j)=1 (52) If Lav(j)>Lmax and β(j)>βmax, then η(j)=0 (53) Equations (52) and (53) are the plot P where the adjacent distance index Lav(j) is equal to or less than the index upper limit value Lmax. j and plot P where the ratio β(j) to the reference is equal to or less than the upper limit value βmax j This means that the aircraft position candidates are extracted.

[0071] Without calculating the reference ratio β(j), the adjacent distance index Lav(j) is compared with the threshold value, and the plot P j It may be determined whether to use the position of the aircraft as a candidate. That is, the equations (52) and (53) may be changed to the following equations (52A) and (53A). Lav(j)≦Lmax or Lav(j)≦βmax*L h If η(j)=1 (52A) Lav(j)>Lmax and Lav(j)>βmax*L h If η(j)=0 (53A)

[0072] Note that expressions (52A) and (53A) have the same meaning as the following expressions: max(X, Y) is a function that returns the maximum value of X and Y. max() can take three or more arguments. Lav(j)≦max(Lmax, βmax*L h ), then η(j)=1 (52B) Lav(j)>max(Lmax, βmax*L h ), then η(j)=0 (53B)

[0073] When formulas (52A), (53A) or formulas (52B), (53B) are used, the plot P where the adjacent distance index Lav(j) is equal to or less than the index upper limit value Lmax j and plot P where the ratio β(j) to the reference is equal to or less than the upper limit value βmax j This corresponds to extracting the aircraft position candidates.

[0074] The aircraft position calculation unit 18A calculates the center of the smallest circle that encompasses all aircraft position candidates as the aircraft position when the aircraft is on the Earth's surface, and calculates the center of the smallest sphere that encompasses all aircraft position candidates as the aircraft position when the aircraft is in the air.

[0075] First, let's consider the case where an aircraft is on the Earth's surface. A circle that contains all points on a plane is either a circle whose diameter is the line segment connecting two points, or the circumscribing circle of a triangle with three vertices. Therefore, the aircraft's position is calculated using the center of a circle whose diameter is the line segment connecting the two plots with the greatest adjacent distance as the initial value. If a circle whose diameter is the line segment connecting the two plots contains all the plots, the center of that circle is taken as the aircraft's position. If there are plots not included, the plot farthest from the center of the circle at that time is added to the circle that is not included, and the circumscribing circle of the triangle is determined. If the circumscribing circle of the triangle contains all the plots, the center of the circumscribing circle is taken as the aircraft's position. If there are plots not included, a new triangle is determined by replacing the plot farthest from the center of the circumscribing circle at that time with the plot at the vertex of the triangle closest to that plot until the circumscribing circle of the triangle contains all the plots, and the process of determining the circumscribing circle is repeated. The center of the circumscribing circle that contains all the plots is taken as the aircraft's position.

[0076] 2 plots P a =(xa,ya), P b =(xb,yb) = the midpoint of the aircraft position P P =(xp,yp), the following holds: xp=(1 / 2)*(xa+xb) (54) yp=(1 / 2)*(ya+yb) (55) rmin=(1 / 2)*√((xb-xa) 2 +(yb-ya) 2 ) (56)

[0077] 3 plots P a , P b , P c = (xc, yc) is the circumcenter of the triangle with vertices at aircraft position P P If so, the following holds: xp=(1 / 2)*((xa 2 +ya 2 )*(yb-yc)+(xb 2 +yb 2 )*(yc-ya)+(xc2 +yc 2 )*(ya-yb)) / ((xa-xb)*(yb-yc)-(xb-xc)*(ya-yb)) (57) yp=(1 / 2)*((xa 2 +ya 2 )*(xb-xc)+(xb 2 +yb 2 )*(xc-xa)+(xc 2 +yc 2 )*(xa-xb)) / ((xb-xc)*(ya-yb)-(xa-xb)*(yb-yc)) (58) rmin=√((xa-xp) 2 +(ya-yp) 2 ) (59)

[0078] Aircraft position P P and each plot P j Center distance L between x (j) can be calculated as follows: L x (j)=√((xj-xp) 2 +(yj-yp) 2 ) (60)

[0079] When an aircraft is in the air, the sphere that contains all the points placed in space is either a sphere whose diameter is the line segment connecting two points, the circumscribing sphere of a triangle determined by three points, or the circumscribing sphere of a tetrahedron with four vertices. Therefore, the aircraft position is calculated using as the initial value a sphere whose diameter is the line segment connecting the two plots that maximizes the adjacent distance. If the sphere whose diameter is the line segment connecting the two plots contains all the plots, the center of that sphere is used as the aircraft position. If there are any plots that are not included, the plot that is farthest from the center of the sphere is added among the plots not included in the sphere, and the circumscribing sphere of the triangle determined by the three plots is found.

[0080] If the circumscribing sphere of the triangle determined by the three plots contains all of the plots, the center of the circumscribing sphere is taken to be the aircraft's position. If there are plots not included, the plot farthest from the center of the circumscribing sphere at that point is added, and the circumscribing sphere of a tetrahedron with the four plots as vertices is determined. The center of the circumscribing sphere of a tetrahedron is the intersection of the perpendicular bisectors of the three sides of the tetrahedron. If the circumscribing sphere of the tetrahedron contains all of the plots, the center of the circumscribing sphere is taken to be the aircraft's position. If there are plots not included, the plot farthest from the center of the circumscribing sphere at that point is replaced with the plot closest to that farthest plot among the four plots that form the vertices of the tetrahedron, and a new tetrahedron with the four plots as vertices is determined, and the process of determining the circumscribing sphere of that tetrahedron is repeated. The center of the circumscribing sphere that contains all of the plots is taken to be the aircraft's position.

[0081] 2 plots P a =(xa,ya,za), P b =(xb,yb,zb) = the midpoint of aircraft position P P =(xp,yp,zp), the following holds: xp=(1 / 2)*(xa+xb) (61) yp=(1 / 2)*(ya+yb) (62) zp=(1 / 2)*(za+zb) (63) rmin=(1 / 2)*√((xb-xa) 2 +(yb-ya) 2 +(zb-za) 2 ) (64)

[0082] 3 plots P a , P b , P c = (xc, yc, yc) is the circumcenter of the triangle with vertices at aircraft position P P If so, the following holds: xp=ga*xa+gb*xb+gc*xc (65) yp=ga*ya+gb*yb+gc*yc (66) zp=ga*za+gb*zb+gc*zc (67) ga=(1 / gd)*((xb-xc) 2+(yb-yc) 2 +(zb-zc) 2 ) *((xb-xa)*(xc-xa)+(yb-ya)*(yc-ya)+(zb-za)*(zc-za)) (68) gb=(1 / gd)*((xc-xa) 2 +(yc-ya) 2 +(zc-za) 2 ) *((xa-xb)*(xc-xb)+(ya-yb)*(yc-yb)+(za-zb)*(zc-zb)) (69) gc=(1 / gd)*((xb-xa) 2 +(yb-ya) 2 +(zb-za) 2 ) *((xa-xc)*(xb-xc)+(ya-yc)*(yb-yc)+(za-zc)*(zb-zc)) (70) gd=2*(xa*(yb-yc)+xb*(yc-ya)+xc*(ya-yb)) 2 +(ya*(zb-zc)+yb*(zc-za)+yc*(za-zb)) 2 +(za*(xb-xc)+zb*(xc-xa)+zc*(xa-xb)) 2 ) (71) rmin=√((xa-xp) 2 +(ya-yp) 2 +(za-zp) 2 ) (72)

[0083] 4 plots P a , P b , P c , P d = (xd, yd, yd) is the center of the circumscribing sphere of the tetrahedron with vertices at aircraft position P P In this case, the vector P b P a , vector P c P a , vector P d P a The aircraft position P is calculated by the matrix [A] below, which summarizes the above. Pcan be calculated as follows:

[0084]

number

[0085] The radius of the circumscribing sphere can be calculated using equation (72). Aircraft position P P and each plot P j Center distance L between x (j) can be calculated as follows: L x (j)=√((xj-xp) 2 +(yj-yp) 2 +(zj-zp) 2 ) (75)

[0086] The operation will be described. The process in which the aircraft monitoring device 1A obtains the aircraft position and updates the trajectory will be described with reference to Fig. 11. Fig. 11 is a flowchart illustrating the process in which the aircraft monitoring device according to the first modified example of the first embodiment obtains the aircraft position and updates the trajectory. The differences between Fig. 11 and Fig. 6 in the case of the aircraft monitoring device 1 will be described.

[0087] In step S25A, the aircraft position candidate extraction unit 17A extracts a plot P where the adjacent distance index calculated by the weighted average of a predetermined number of adjacent distances from the smallest is equal to or less than the upper limit value, or the ratio of the reference adjacent distance index to the adjacent distance index is equal to or less than the upper limit value. j In step S26A, the aircraft position calculation unit 18A extracts the aircraft position P from the aircraft position candidates. P The aircraft position calculation unit 18A calculates the center of the smallest circle or sphere that includes all the aircraft position candidates as the aircraft position P P Let's say.

[0088] The process of extracting aircraft position candidates by the aircraft position candidate extraction unit 17A will be described with reference to Fig. 12. Fig. 12 is a flowchart illustrating the process of extracting aircraft position candidates from a plot by the aircraft position candidate extraction unit provided in the aircraft monitoring device according to the first modification of embodiment 1. Regarding Fig. 12, the differences from Fig. 7 in the case of the aircraft position candidate extraction unit 17 will be described.

[0089] In step S33A, the aircraft position candidate extraction unit 17A refers to the ordered distance Lm(j,q) and the weighting coefficient ξq to generate the plot P j In step S40 after S33A, the aircraft position candidate extraction unit 17A calculates the reference adjacent distance index L, which is the average of the smallest to the second highest number h of adjacent distance indexes Lav(j). h is calculated by the formula (50). In step S41, the aircraft position candidate extraction unit 17A extracts the position of each plot P j The reference ratio β(j) is calculated using equation (51).

[0090] In step S35A, it is checked whether Lav(j)≦Lmax or β(j)≦βmax is satisfied. If Lav(j)≦Lmax or β(j)≦βmax is satisfied (YES in S35A), the plot P j is an aircraft position candidate (η(j)=1). If Lav(j)>Lmax and β(j)>βmax are satisfied (NO in S35A), in step S37, plot P j is not an aircraft position candidate (η(j)=0).

[0091] 13 and 14, the aircraft position calculation unit 18A calculates the aircraft position P P 13 and 14 are flowcharts illustrating the process of determining an aircraft position from aircraft position candidates by an aircraft position calculation unit included in an aircraft monitoring device according to a first modification of the first embodiment. Fig. 13 shows the first half of the flowchart, and Fig. 14 shows the second half of the flowchart.

[0092] In step S51, the two plots P with the largest adjacent distance L(j, k) are j0 and P k0 In step S52, the vertex array H=(a,b,c,d)=(j0,k0,-1,-1) is set. In step S53, it is checked whether the calculation mode MD is "air". If the calculation mode is not "air" (NO in S53), in step S54, the line segment P on the Earth's surface is calculated. a P b The midpoint of the aircraft position P p and the minimum radius rmin is half the length of the line segment PaPb. That is, in equations (54) to (56), the aircraft position P p = (xp, yp), and calculate the minimum radius rmin. j Center distance L x (j) is calculated using equation (60). In step S56, all the center-to-center distances L x Check whether (j) is equal to or smaller than the minimum radius rmin. All center-to-center distances L x (j) is L x If (j)≦rmin or less (YES in S56), the process ends.

[0093] L x (j)>rmin, L x If (j) exists (NO in S56), in step S57, x (j) is the plot P jn In step S58, the vertex array H=(a,b,c,-1)=(j0,k0,jn,-1) is set. In step S59, the triangle P on the surface of the Earth is calculated. a P b P c The circumcenter of the aircraft position P p Let P be the triangle a P b P c The radius of the circumscribing circle is the minimum radius rmin. In other words, in equations (57) to (59), the aircraft position P p = (xp, yp), and calculate the minimum radius rmin. j Center distance L x(j) is calculated. In step S61, all the center-to-center distances L x Check whether (j) is equal to or smaller than the minimum radius rmin. All center-to-center distances L x (j) is L x If (j)≦rmin or less (YES in S61), the process ends.

[0094] L x (j)>rmin, L x If (j) exists (NO in S61), in step S62, x (j) is the plot P jn In step S63, the plot P a , P b , P c Plot P jn Plot the closest one to P jn and set a new vertex array H=(a, b, c, −1). Return to step S59.

[0095] If the calculation mode is "in the air" (YES in S53), in step S64, the line segment P a P b The midpoint of the aircraft position P p and the minimum radius rmin is half the length of the line segment PaPb. That is, in equations (61) to (64), the aircraft position P p = (xp, yp, zp), and calculate the minimum radius rmin. j Center distance L x (j) is calculated using equation (75). In step S66, all the center-to-center distances L x Check whether (j) is equal to or smaller than the minimum radius rmin. All center-to-center distances L x (j) is L x If (j)≦rmin or less (YES in S66), the process ends.

[0096] L x (j)>rmin, L x If (j) exists (NO in S66), in step S67, x (j) is the plot Pjn In step S68, the vertex array H=(j0, k0, jn, -1) is set. In step S69, the triangle P a P b P c The circumcenter of the aircraft position P p In equations (65) to (72), the aircraft position P p = (xp, yp, zp), and calculate the minimum radius rmin. j Center distance L x (j) is calculated using equation (75). In step S71, all the center-to-center distances L x Check whether (j) is equal to or smaller than the minimum radius rmin. All center-to-center distances L x (j) is L x If (j)≦rmin or less (YES in S71), the process ends.

[0097] L x (j)>rmin, L x If (j) exists (NO in S71), in step S72, x (j) is the plot P jn In step S73, the vertex array H=(a, b, c, jn) is set. In step S74, the tetrahedron P a P b P c P d The center of the circumscribed sphere is the aircraft position P p In equations (72) to (74), the aircraft position P p = (xp, yp, zp), and calculate the minimum radius rmin. j Center distance L x (j) is calculated using equation (75). In step S76, all the center-to-center distances L x Check whether (j) is equal to or smaller than the minimum radius rmin. All center-to-center distances L x (j) is L x If (j)≦rmin or less (YES in S76), the process ends.

[0098] L x (j)>rmin, L xIf (j) exists (NO in S76), in step S77, x (j) is the plot P jn In step S78, plot P a , P b , P c , P d Plot P jn Plot the closest one to P jn and set a new vertex array H=(a, b, c, d). Return to step S74.

[0099] FIG. 15 shows the aircraft position determined by the aircraft monitoring device 1A with respect to the plot shown in FIG. 8. FIG. 15 is a diagram showing aircraft position candidates and the aircraft position determined from the plot 90 by an aircraft monitoring device according to a first modification of the first embodiment. In FIG. 15, the smallest circle (called the inclusive circle) 95 that includes all aircraft position candidates is shown by a dashed line. The aircraft position 96 determined by the aircraft monitoring device 1A as the center of the inclusive circle is shown by a triangle (△). The aircraft monitoring device 1A can also determine the aircraft position 96 at a position close to the line 93 that is an extension of the trajectory.

[0100] The aircraft monitoring device 1A transmits a response signal from the aircraft 4 to each receiving station 3. j The time of reception and each receiving station 3 j By using this position data, the aircraft position can be determined with reduced variation no matter where the aircraft 4 is located. The aircraft's trajectory can also be made to be a natural curve.

[0101] The aircraft position candidate extraction part is Plot P j The plot P is a plot in which the adjacent distance index Lav(j) is equal to or smaller than the index upper limit Lmax and the reference ratio β(j) is equal to or smaller than the ratio upper limit βmax. j may be extracted as an aircraft position candidate. In that case, the plot P j Determine whether to consider the position of the aircraft as a candidate. If Lav(j)≦Lmax and β(j)≦βmax, then η(j)=1 (76) If Lav(j)>Lmax or β(j)>βmax, then η(j)=0 (77)

[0102] Without calculating the ratio β(j) to the reference, the plot P is calculated using the following equations (76A) and (77A) instead of equations (76) and (77). j may be determined as an aircraft position candidate. Lav(j)≦Lmax and Lav(j)≦βmax*L h If η(j)=1 (76A) Lav(j)>Lmax or Lav(j)>βmax*L h If η(j)=0 (77A)

[0103] Equations (76A) and (77A) are equivalent to the following equations (76B) and (77B). min(X,Y) is a function that returns the minimum value between X and Y. min() can take three or more arguments. Lav(j)≦min(Lmax, βmax*L h ), then η(j)=1 (76B) Lav(j)>min(Lmax, βmax*L h ), then η(j)=0 (77B)

[0104] When using equations (76A), (77A) or (76B), (77B), plot P j The plot P is a plot in which the adjacent distance index Lav(j) is equal to or smaller than the index upper limit Lmax and the reference ratio β(j) is equal to or smaller than the ratio upper limit βmax. j This corresponds to extracting the aircraft position candidates.

[0105] Second variant. The second modified example is a modification of the first embodiment in the following two respects. (a) The adjacent distance index is calculated by a weighted average. (i) The reference adjacent distance index is calculated by taking a weighted average of a predetermined number of adjacent distance indexes starting from the smallest adjacent distance index, and only plots having an adjacent distance index whose ratio to the reference adjacent distance index is less than or equal to an upper limit value are extracted as aircraft position candidates.

[0106] The functional configuration of an aircraft monitoring device 1B according to a second modified example of the first embodiment will be described with reference to Fig. 16. Fig. 16 is a block diagram illustrating the functional configuration of an aircraft monitoring device according to a second modified example of the first embodiment. Regarding Fig. 16, differences from Fig. 2 in the case of the first embodiment will be described. Compared to the aircraft monitoring device 1, the aircraft monitoring device 1B has a modified data storage unit 11B and an aircraft position candidate extraction unit 17B.

[0107] The data storage unit 11B also has a weighting coefficient 38, a reference adjacent distance index 39, a second top number 40, a ratio to the reference 41, a ratio upper limit value 42, and a weighting coefficient 46. The data storage unit 11B does not have an index upper limit value 33. The weighting coefficient 38 relates to the change in (A). The reference adjacent distance index 39, the second top number 40, the ratio to the reference 41, the ratio upper limit value 42, and the weighting coefficient 46 relate to the change in (B2). The reference adjacent distance index 39, the second top number 40, the ratio to the reference 41, and the ratio upper limit value 42 are the same as those in the data storage unit 11A.

[0108] Define the following variables to represent the newly added data. ζj: the weighting coefficient used to calculate the weighted reference neighbor distance index Lh. It is stored as the weighting coefficient 46.

[0109] The aircraft position candidate extraction unit 17B refers to the ordered distance Lm(j,q) and the weighting coefficient ξq to generate the plot P j The adjacent distance index Lav(j) is calculated using equation (47).

[0110] The aircraft position candidate extraction unit 17B uses the reference adjacent distance index L h is calculated using the formula below. L h =Σζj*Lav(j) (78) In equations (78) and (79), Σ represents the sum of j=1,...,h. The weighting coefficients ζj are determined so that their sum is 1, as shown below. Σζj=1 (79) 0≦ζj≦1 (80)

[0111] The weighting coefficient ζj is the weighting coefficient of the plot P j Plot P of a second number (h) of consecutive values ​​in the sequence containing the smallest j Each plot P included in the individual calculation position set is j is the second weighting coefficient determined based on the jth position from the smallest in the individual calculation position set. h is the second weighting coefficient ζj and each plot P included in the individual calculation position set. j The weighting coefficient ζj may be determined as ζj=1 / h regardless of j. In this case, equation (78) also calculates the sum of products of the second weighting coefficient ζj and the adjacent distance index Lav(j).

[0112] The aircraft position candidate extraction unit 17B calculates the ratio β(j) to the reference using equation (51). The aircraft position candidate extraction unit 17B compares the ratio β(j) to the reference ratio with the upper limit value βmax, and generates a plot P j Determine whether to consider the position of the aircraft as a candidate. If β(j)≦βmax, then η(j)=1 (81) If β(j)>βmax, then η(j)=0 (82) Equations (81) and (82) are the plot P where the ratio β(j) to the reference is equal to or less than the upper limit βmax. j This means extracting the aircraft position candidate.

[0113] The adjacent distance index Lav(j) may be compared with a threshold value without calculating the reference ratio β(j). That is, η(j) may be determined by the following equations (81A) and (82A) instead of equations (81) and (82). Lav(j)≦βmax*L h If η(j)=1 (81A) Lav(j)>βmax*L h If η(j)=0 (82A)

[0114] Even when formulas (81A) and (82A) are used, the plot P where the ratio β(j) to the reference is equal to or less than the upper limit βmax j This corresponds to extracting the aircraft position candidates.

[0115] The operation will be described. Referring to Fig. 17, the process in which the aircraft monitoring device 1B obtains the aircraft position and updates the trajectory will be described. Fig. 17 is a flowchart illustrating the process in which the aircraft monitoring device according to the first modified example of the first embodiment obtains the aircraft position and updates the trajectory. Regarding Fig. 17, the differences from Fig. 6 in the case of the aircraft monitoring device 1 will be described.

[0116] In step S25B, the aircraft position candidate extraction unit 17B calculates the adjacent distance index Lav(j) as the reference adjacent distance index L h The plot P where the ratio β(j) divided by is equal to or less than the upper limit βmax j is extracted as an aircraft position candidate. The adjacent distance index Lav(j) is calculated by taking the weighted average of the adjacent distances of a predetermined number (m) from the smallest. The reference adjacent distance index L h is calculated as a weighted average of the neighbor distance index Lav(j) of a predetermined number (h) from the smallest.

[0117] The process of extracting aircraft position candidates by the aircraft position candidate extraction unit 17B will be described with reference to Fig. 18. Fig. 18 is a flowchart illustrating the process of extracting aircraft position candidates from a plot by the aircraft position candidate extraction unit included in the aircraft monitoring device according to the first modification of embodiment 1. Regarding Fig. 18, the differences from Fig. 7 in the case of the aircraft position candidate extraction unit 17 will be described.

[0118] In step S33A, the aircraft position candidate extraction unit 17B refers to the ordered distance Lm(j,q) and the weighting coefficient ξq to generate the plot P j In step S40B after S33A, the aircraft position candidate extraction unit 17B calculates the reference adjacent distance index L, which is the weighted average of the smallest to second-highest number (h) of adjacent distance indexes Lav(j). h is calculated by the formula (78). In step S41, the aircraft position candidate extraction unit 17B calculates the position of each plot P j The ratio β(j) to the reference is calculated using equation (51). The processes of S33A and S41 are the same as those of the aircraft position candidate extraction unit 17A.

[0119] In step S35B, the aircraft position candidate extraction unit 17B checks whether β(j)≦βmax is true. If β(j)≦βmax is true (YES in S35B), in step S36, the plot P j is an aircraft position candidate (η(j)=1). If β(j)>βmax holds (NO in S35B), in step S37, plot P j is not an aircraft position candidate (η(j)=0).

[0120] The aircraft monitoring device 1B transmits the response signal from the aircraft 4 to each receiving station 3. j The time of reception and each receiving station 3 j By using this position data, the aircraft position can be determined with reduced variation no matter where the aircraft 4 is located. The aircraft's trajectory can also be made to be a natural curve.

[0121] Plot P j The set of plots determined from the adjacent distance set of P j The set of adjacent plots is called the set of plots P j The set of adjacent plots of the plot P j Plot P is a set of plots (individual calculation positions) that have any of the adjacent distances included in the adjacent distance set of jThe adjacent plot set of is a set of adjacent individual calculation positions of an individual calculation position, which is a set of individual calculation positions having any adjacent distance included in the adjacent distance set. A plot P that satisfies the adjacent set condition, which is determined using the adjacent plot set of the plot, rather than the adjacent distance condition. j may be extracted as an aircraft position candidate.

[0122] The adjacent distance index may be calculated not from the adjacent distance but from the ranking distance, which indicates the nearest position of the player from the other player's perspective.

[0123] The second weighting coefficient ζj is used to calculate the reference neighbor distance index L h and extracting aircraft position candidates using the to-reference ratio β(j) can also be applied to cases where an adjacent distance index is calculated using a method other than that shown in the first embodiment and the modified examples. The above description of the first embodiment and its modifications also applies to the other embodiments and their modifications. The same applies to the other embodiments and their modifications.

[0124] Embodiment 2 The aircraft monitoring device of embodiment 2 calculates the adjacent distance, which is the distance between two plots, sorts the adjacent distances for each plot in ascending order, and uses the smallest adjacent distance between itself and another plot among the adjacent distances of the other plots (called the ranking distance) as the distance between itself and the other plot.

[0125] The functional configuration of an aircraft monitoring device 1C according to the second embodiment will be described with reference to Fig. 19. Fig. 19 is a block diagram illustrating the functional configuration of an aircraft monitoring device according to the second embodiment. Regarding Fig. 19, differences from Fig. 2 in the case of the aircraft monitoring device 1 will be described. In the aircraft monitoring device 1C, the data storage unit 11C, the aircraft position candidate extraction unit 17C, and the aircraft position calculation unit 18C have been changed.

[0126] The data storage unit 11C has an ordering number 47, an adjacent order 48, an order distance 49, and an order distance index 50. In the data storage unit 11C, the index upper limit value 33 is changed to an index upper limit value 33C.

[0127] The ordering number 47, adjacent rank 48, rank distance 49, rank distance index 50, and index upper limit value 33C can be explained more easily and accurately by using variables, so the variables that represent these data will be explained. Rm(j,q): called the ordering number. j is the plot P j The ordering number Rm(j,q) is the number of the plot P. j When the adjacent distance L(j,k) is sorted in ascending order for each plot, the plot P with the adjacent distance L(j,k) is k The numbers (k) of the elements j, k are arranged in ascending order of the adjacent distance L(j, k). Rm(j, q) is stored as the ordering number 47. If Lm(j,q)=L(j,k), then Rm(j,q)=k. Rq(j,k): called the neighbor ranking. j and k are the plot P j Plot P j In the ordering number Rm(j,q), plot P k Rq(j,k) is stored as the adjacent rank 48. If Rm(j, q)=k, then Rq(j, k)=q. Lr(j,q): called the rank distance. j is the plot P j q is the storage position of the array. Plot P of the number (k) stored in the ordering number Rm(j,q) k Plot in P j This is an array that stores the adjacent ranking Rq(k,j) of each node. Lr(j,k) is stored as the ranking distance 49. If k=Rm(j,q), then Lr(j,q)=Rq(k,j) Lrav(j): Plot P jLrav(j) is the rank distance index of the plot Pj. It is the average of the m smallest rank distances of the plot Pj. Lrav(j) is stored as the rank distance index 50. Lrmax: a constant that is compared with the rank distance index Lrav(j). Lrmax is stored as the index upper limit value 33C.

[0128] Rq(j,k) is the plot P j The individual calculation positions and plots P k The adjacent distance L(j, k) between the other individual calculation position is plotted as P k The distance ranking Rq(j,k) indicates the distance ranking from smallest to largest in the adjacent distance set LL(k). The distance ranking Rq(j,k) corresponds to the adjacent distance L(j,k). The ranking distance index Lrav(j) is an adjacent distance index determined based on the adjacent distance set LL(j).

[0129] Using the ordered number Rm(j,q), plot P j To do this, we define the following variables: LP(j): Plot P j A variable representing a set of adjacent plots. LP(j)={Rm(j,q)|q is an integer between 1 and m} m is predetermined and stored as the top 32. Plot P j The set of adjacent plots LP(j) of plot P j Plot the distance P of any of the m consecutive ordered distances Lm(j,q) including the smallest one in the sequence Lm(j,q) of adjacent distances sorted in ascending order for each j Plot P j is a set of.

[0130] The aircraft position candidate extraction unit 17C calculates the adjacent distance L(j, k) using equation (39). The aircraft position candidate extraction unit 17C references the adjacent distance L(j, k) to determine the ordered distance Lm(j, q), the ordered number Rm(j, q), and the adjacent rank Rq(j, k). Lm(j, q) is an array in which L(j, k) is arranged in ascending order from smallest to largest. When setting Lm(j, q) = L(j, k), Rm(j, q) = k and Rq(j, k) = q are set.

[0131] The aircraft position candidate extraction unit 17C sets the ranking distance Lr(j,q) by referring to the ordering number Rm(j,q). The aircraft position candidate extraction unit 17C sets the ranking distance Lr(j,q) by the following formula: Lr(j,q)=Rq(Rm(j,q),j) (83)

[0132] The aircraft position candidate extraction unit 17C refers to the ranking distance Lr(j,q) and extracts the position of the aircraft from the plot P j The ranking distance index Lrav(j) is calculated using the formula below. Lrav(j)=(1 / m)*ΣLr(j,q) (84) In equation (84), Σ represents the sum of q=1,...,m.

[0133] The aircraft position candidate extraction unit 17C extracts the aircraft position candidate from the plot P j The ranking distance index Lrav(j) is compared with the index upper limit Lrmax, and the plot P j Determine whether to consider the position of the aircraft as a candidate. If Lrav(j)≦Lrmax, η(j)=1 (85) If Lrav(j)>Lrmax, η(j)=0 (86)

[0134] The ordering number Rm(j,q), adjacent order Rq(j,k), and order distance Lr(j,q) will be explained with reference to Figures 20 and 21. Figure 20 is a diagram illustrating, by way of example, the ordering number, adjacent order, and order distance used by the aircraft position candidate extraction unit of the aircraft monitoring device according to the second embodiment. Figure 20 shows an example of a plot. The plots are indicated by white circles. The numbers of the plots are indicated within the circles. Figures 21(A), (B), and (C) respectively show the ordering number Rm(j,q), adjacent order Rq(j,k), and order distance Lr(j,q). Figure 21(D) also shows Lrav(j) and η(j) when m = 3 and Lrmax = 4.5. Plots P2 and P5, which are far from the others, are excluded from the aircraft position candidates.

[0135] The operation will be described. Referring to Fig. 22, the process in which the aircraft monitoring device 1C obtains the aircraft position and updates the trajectory will be described. Fig. 22 is a flowchart explaining the process in which the aircraft monitoring device according to the second embodiment obtains the aircraft position and updates the trajectory. Regarding Fig. 22, the differences from Fig. 6 in the case of the aircraft monitoring device 1 will be described.

[0136] In step S25C, the aircraft position candidate extraction unit 17C extracts the plot P P whose rank distance index, which is the average of the rank distances of a predetermined number from the minimum, is equal to or less than the upper limit. j are extracted as aircraft position candidates.

[0137] The process of extracting aircraft position candidates by the aircraft position candidate extraction unit 17C will be described with reference to Fig. 23. Fig. 23 is a flowchart illustrating the process of extracting aircraft position candidates from a plot by the aircraft position candidate extraction unit included in the aircraft monitoring device according to embodiment 2. Regarding Fig. 23, the differences from Fig. 7 in the case of the aircraft position candidate extraction unit 17 will be described.

[0138] In step S32C, the aircraft position candidate extraction unit 17C extracts the aircraft position candidate from each plot P jFor each pair, calculate the ordered distance Lm(j,q), which is an array in which the adjacent distances L(j,k) are arranged in ascending order, the ordered number Rm(j,q), and the adjacent rank Rq(j,k). Here, in the ordered distance Lm(j,q), the ordered number Rm(j,q), and the adjacent rank Rq(j,k), j and k are plot P j is the number, and q indicates the number from the smallest.

[0139] In step S42 after S32C, the aircraft position candidate extraction unit 17C sets the ranking distance Lr(j,q) by equation (83) with reference to the ordering number Rm(j,q) and the adjacent ranking Rq(j,k).

[0140] In step S33C, the aircraft position candidate extraction unit 17C refers to the ranking distance Lr(j, q) and extracts the position of the aircraft from the plot P j In step S35C, it is checked whether Lrav(j)≦Lrmax is satisfied. If Lrav(j)≦Lrmax is satisfied (YES in S35C), in step S36, the rank distance index Lrav(j) of the plot P j is an aircraft position candidate (η(j)=1). If Lrav(j)≦Lrmax is not established (NO in S35C), in step S37, the plot P j is not an aircraft position candidate (η(j)=0).

[0141] The aircraft monitoring device 1C can also determine the aircraft position at a position close to the line extending the trajectory, similar to the aircraft monitoring device 1. The aircraft monitoring device 1C transmits a response signal from the aircraft 4 to each receiving station 3. j The time of reception and each receiving station 3 j By using this position data, the aircraft position can be determined with reduced variation no matter where the aircraft 4 is located. The aircraft's trajectory can also be made to be a natural curve.

[0142] The rank distance index Lrav(j) may be calculated using the weighting coefficients ξq, i.e., the plot P j The ranking distance index Lrav(j) may be calculated using the formula below. Lrav(j)=Σξq*Lr(j,q) (87) In equation (87), Σ represents the sum of q=1,...,m.

[0143] A reference rank distance index, which is the average or weighted average of a predetermined number of rank distance indexes Lrav(j) starting from the smallest, may be calculated, and aircraft position candidates may be extracted using a reference ratio, which is the ratio between the rank distance index Lrav(j) and the reference rank distance index, or using only the reference ratio.

[0144] Embodiment 3 The aircraft position monitoring device according to the third embodiment connects the own plot and the other plot when the other plot is one of the plots that is closest to the own plot by m positions, and the own plot is one of the plots that is closest to the other plot by m positions. The plot included in the set with the largest number of plots among the connected plots is determined to be the aircraft position candidate.

[0145] The functional configuration of the aircraft monitoring device 1D according to the third embodiment will be described with reference to Fig. 24. Fig. 24 is a block diagram illustrating the functional configuration of the aircraft monitoring device according to the third embodiment. Regarding Fig. 24, differences from Fig. 2 in the case of the aircraft monitoring device 1 will be described. In the aircraft monitoring device 1D, the data storage unit 11D and the aircraft position candidate extraction unit 17D have been changed.

[0146] The data storage unit 11D does not have the adjacent distance index 31 and the index upper limit value 33. The data storage unit 11D has an ordering number 47, an adjacent order 48, a linkability 51, a plot set 52, a number of belonging 53, and a candidate set number 54. The ordering number 47 and the adjacent order 48 are the same data as those stored in the data storage unit 11C. The linkability 51 is determined by the number of plots P j and plot P k The plot set 52 is data that stores whether or not each plot P can be connected to the same plot set. j The number of belonging 53 is the number of plots P belonging to the plot set. jThe candidate set number 54 is the data that stores the number of the plot P j The number of the plot set with the largest number of plots P is stored. j is the smallest number.

[0147] Define the following variables: Rr(j,k): Plot P j and plot P k This data indicates whether or not the plots can be linked to the same plot set. j Plot in P k The neighbor ranking Rq(j,k) of is less than or equal to m, and the plot P k Plot in P j If the neighbor ranking Rq(k,j) of is less than or equal to m, plot P j and plot P k and can be connected, and Rr(j,k) = Rr(k,j) = 1. If not, plot P j and plot P k and are not connectable, and Rr(j,k) = Rr(k,j) = 0. Rr(j,k) is stored in the connectability 51. SS(j): each plot P j The plot set is the data of the plot set to which P belongs. j The plots SS(j) are stored in a plot set 52. Nn(j): Plot P belonging to plot set SS(j) j It is called the number of belonging to the plot set. Nn(j) is stored in the number of belonging 53. The number of plots P belonging to the plot set SS(j) j At the smallest number jmin among the numbers, Nn(jmin)>0. That is, j where SS(j)=j is jmin. SS(j) <jであるjでは、Nn(j)=0である。 Nnmax: The number of the plot set for which Nn(j) is the maximum. This represents the number of the plot set that is the aircraft position candidate. This is called the candidate set number. Nnmax is stored in the candidate set number 54.

[0148] The aircraft position candidate extraction unit 17D, like the aircraft position candidate extraction unit 17C, determines the adjacent distance L(j, k), the ordered distance Lm(j, q), the ordered number Rm(j, q), and the adjacent rank Rq(j, k).

[0149] The aircraft position candidate extraction unit 17D refers to the adjacent rank Rq(k,j) to determine the connectability Rr(j,k). If Rq(j,k)≦m and Rq(k,j)≦m, then Rr(j,k)=Rr(k,j)=1 (88) If Rq(j,k)>m or Rq(k,j)>m, then Rr(j,k)=Rr(k,j)=0 (89)

[0150] Equation (88) is plot P j Plot P in the adjacent plot set LP(j) k and plot P k Plot P in the adjacent plot set LP(k) j When the plot P j and plot P k This means that the plot P j Plot P in the adjacent plot set LP(j) k If it is not included, or if the plot P k Plot P in the adjacent plot set LP(k) j If it does not contain, plot P j and plot P k This means that the and are not concatenable.

[0151] The aircraft position candidate extraction unit 17D refers to the connection possibility Rr(j, k) and extracts each plot P j The aircraft position candidate extraction unit 17D determines the plot set SS(j) to which the plot P belongs when Rr(j,k)=1. j and plot Pk In the plot set SS(j), the plot P belonging to the plot set is j The plot P belongs to the plot set. j The minimum value of the number is set.

[0152] The aircraft position candidate extraction unit 17D refers to the plot set SS(j) and extracts the plots P belonging to each plot set. j The aircraft position candidate extraction unit 17D determines the number of the plots P that maximizes Nn(j). j The number jmax is set as the candidate set number Nnmax (Nnmax=jmax).

[0153] The aircraft position candidate extraction unit 17D extracts the plot P whose plot set SS(j) has the candidate set number Nnmax. j is the aircraft position candidate. If SS(j)=Nnmax, then η(j)=1 (90) If SS(j)≠Nnmax, then η(j)=0 (91)

[0154] Plot P j Plot in P k Plot P where the neighbor ranking Rq(j,k) of is less than or equal to m k The set of plots P j In the plot set SS(j), the plots P with the same number are j The set of plots P j The set of plots P j and plot P k Between them, the individual calculation position is plot P j The adjacent plot set LP(j) is the plot P k and plot P k Plot P in the adjacent plot set LP(k) k The aircraft position candidate extraction unit 17D extracts the aircraft position candidate from the plot P j Based on the set of adjacent plots LP(j), each plot Pj Determine whether they belong to the same group. Plot P j The condition for finding an aircraft position candidate that is determined to be based on the same group based on the adjacent plot set LP(j) of the plot P j This is the neighbor set condition determined using the neighbor plot set LP(j).

[0155] The operation will be described. The process in which the aircraft monitoring device 1D obtains the aircraft position and updates the trajectory will be described with reference to Fig. 25. Fig. 25 is a flowchart explaining the process in which the aircraft monitoring device according to the third embodiment obtains the aircraft position and updates the trajectory. The differences between Fig. 25 and Fig. 6 in the case of the aircraft monitoring device 1 will be described.

[0156] In step S25D, the aircraft position candidate extraction unit 17D extracts the plots P j and plot P k and are grouped into the same plot set, and the plots P j Plot P belongs to the plot set with the largest number of j are extracted as aircraft position candidates.

[0157] The process of extracting aircraft position candidates by the aircraft position candidate extraction unit 17D will be described with reference to Fig. 26 and Fig. 27. Fig. 26 is a flowchart illustrating the process of extracting aircraft position candidates from a plot by the aircraft position candidate extraction unit provided in the aircraft monitoring device according to embodiment 3. Fig. 26 shows the first half of the flowchart, and Fig. 27 shows the second half of the flowchart.

[0158] In step S31, the aircraft position candidate extraction unit 17D extracts two plots P j , P k In step S32C, the aircraft position candidate extraction unit 17D calculates the adjacent distance L(j, k) between the plots for all combinations of the plots P jFor each of the candidates, the ordered distance Lm(j,q), which is an array in which the adjacent distances L(j,k) are arranged in ascending order, the ordered number Rm(j,q), and the adjacent rank Rq(j,k) are calculated. Steps S31 and S32C are the same processes as those in FIG. 23 for the aircraft position candidate extraction unit 17C.

[0159] In step S81, the aircraft position candidate extraction unit 17D refers to the adjacent rank Rq(k,j) and determines whether or not connection is possible Rr(j,k). j , P k If the adjacent rank Rq(j,k) of each pair is m or less (Rq(j,k)≦m and Rq(k,j)≦m), then Rr(j,k)=Rr(k,j)=1 (possible to connect). Otherwise, Rr(j,k)=Rr(k,j)=0 (not possible to connect).

[0160] In step S82, the aircraft position candidate extraction unit 17D initializes the plot set SS(j). The initial value of the plot set SS(j) is j Let belong to the set of plots to which it belongs alone (j = 1, ..., Nb, where SS(j) = j).

[0161] In steps S83 to S93, a plot set SS(j) is determined. In step S83, j=1 is set. In step S84, k=j+1 is set. In step S85, the plot P j , P k Check whether Rr(j,k)=1 is connectable. Plot P j , P k If SS(k) is concatenable (YES in S85), it is checked in step S86 whether SS(k) is greater than SS(j) (SS(k)>SS(j)?).

[0162] If SS(k) is greater than SS(j) (YES in S86), then in step S87, set SS(k) = SS(j). If SS(k) is not greater than SS(j) (NO in S86), then in step S88, check whether SS(k) is less than SS(j) (SS(k) < SS(j)?). If SS(k) is less than SS(j) (YES in S88), then in step S89, add the plot set of SS(j) to the plot set of SS(k). Specifically, for r from SS(j) to k - 1, when (SS(r) = SS(j)?) holds, set SS(r) = SS(k).

[0163] Plot P j , P k If plots P

[0164] are not connectable (NO in S85), if SS(k) is the same as SS(j) (NO in S88), and after the execution of S87 or S89, then in step S90, set k = k + 1. In step S91, check whether k is less than or equal to Nb (k ≤ Nb?). If k is less than or equal to Nb (YES in S91), return to S85. If k is not less than or equal to Nb (NO in S91), then in step S92, set j = j + 1. In step S93, check whether j is less than or equal to Nb (j ≤ Nb?). If j is less than or equal to Nb (YES in S93), return to S84.

[0164] If j is not less than or equal to Nb (NO in S93), then in step S94, initialize the number of affiliated plots Nn(j) to 0. Set Nn(j) = 0 for j = 1, …, Nb. In step S95, set j = 1. In step S96, set r = SS(j) and Nn(r) = Nn(r)+1. In step S97, set j = j + 1. In step S98, check whether j is less than or equal to Nb (j ≤ Nb?). If j is less than or equal to Nb (YES in S98), return to S96.

[0165] If j is not less than or equal to Nb (NO in S98), then in step S99, set the plot set number jmax with the largest number of affiliated plots Nn(j) to the candidate set number Nnmax (Nnmax = jmax).

[0166] In step S100, j=1. In step S101, plot P j Check whether plot P belongs to the largest set of plots (SS(j)=Nnmax?). j belongs to the largest plot set (YES in S101), in step S102, the plot P j Let be the aircraft position candidate (η(j)=1). Plot P j If the plot P does not belong to the largest plot set (NO in S101), then in step S103, j is not an aircraft position candidate (η(j)=0).

[0167] In step S104, j=j+1 is set. In step S105, it is checked whether j≦Nb. If j≦Nb is not satisfied (NO in S105), all plots P j Since it has been checked whether j is an aircraft position candidate, the process ends. If j≦Nb (YES in S105), the process returns to S101.

[0168] The process of the aircraft position candidate extraction unit 17D linking the plots will be described with reference to Fig. 28. Fig. 28 is a diagram illustrating an example of the process of the aircraft position candidate extraction unit of the aircraft monitoring device according to the third embodiment extracting aircraft position candidates from the plots. Fig. 28(A) shows an example of the plots. The plot arrangement is the same as Fig. 20. In Fig. 28(A), the plots that can be linked are connected by dotted lines. Fig. 28(B) shows the initial value of SS(q) and the plot P j , j=1,2,...,7 shows SS(q) after processing.

[0169] The initial value of SS(q) is SS(q) = q. Since plots P1 and P7 can be linked, SS(7) changes to 1 after processing plot P1. Since there is no plot that can be linked to plot P2, SS(q) does not change. Plot P3 can be linked to plots P4, P6, and P8, and the values ​​change to SS(4) = SS(6) = SS(8) = 3.

[0170] Plot P4 can only be linked to plot P3, and since plot P4 is already linked to plot P3, SS(q) does not change even if plot P4 is processed. There is no plot that can be linked to plot P5, so SS(q) does not change. Plot P6 can be linked to plots P7 and P8. Since SS(3) = 3 > SS(7) = 1, S88 becomes YES, and in S89, SS(3) = SS(4) = SS(6) = 1 is changed. Furthermore, plot P8 is linked to plot P7, and SS(8) = 1 is changed. Plot P7 can be linked to plot P8, but since SS(7) = SS(8), SS(q) does not change even if plot P7 is processed.

[0171] After processing, plots P1, P3, P4, P6, P7, and P8 will be in the same plot set. This plot set is the largest with a membership count of Nn(1) = 6. Note that only plot P2 will be in one plot set. Plot P5 will also be in one plot set. Since they belong to the plot set with the largest membership count, plots P1, P3, P4, P6, P7, and P8 will become aircraft position candidates.

[0172] The aircraft monitoring device 1D can also determine the aircraft position at a position close to the line extending the trajectory, similar to the aircraft monitoring device 1. The aircraft monitoring device 1D transmits a response signal from the aircraft 4 to each receiving station 3. j The time of reception and each receiving station 3 j By using this position data, the aircraft position can be determined with reduced variation no matter where the aircraft 4 is located. The aircraft's trajectory can also be made to be a natural curve.

[0173] Embodiment 4 The aircraft monitoring device according to the fourth embodiment estimates the speed and acceleration of the aircraft from past aircraft positions, predicts the aircraft position from the aircraft position, speed, and acceleration at a previous point in time, and if the speed and acceleration are small, calculates the aircraft position from a plot close to the predicted aircraft position. If the aircraft speed or acceleration is high, the aircraft monitoring device 1E according to the fourth embodiment calculates the aircraft position in the same way as the aircraft monitoring device 1. If the aircraft speed or acceleration is high, the aircraft monitoring device 1E calculates the aircraft position based on plots excluding plots that are far from the others.

[0174] The functional configuration of the aircraft monitoring device 1E according to the fourth embodiment will be described with reference to Fig. 27. Fig. 27 is a block diagram illustrating the functional configuration of the aircraft monitoring device according to the fourth embodiment. Regarding Fig. 27, differences from Fig. 2 in the case of the aircraft monitoring device 1 will be described. The aircraft monitoring device 1E also has a speed / acceleration estimation unit 81, an aircraft position prediction unit 82, a second aircraft position candidate extraction unit 83, a second aircraft position calculation unit 84, an aircraft position integration unit 85, and a calculation control unit 86. Furthermore, in the aircraft monitoring device 1E, the data storage unit 11E and the aircraft position calculation unit 18E have been modified.

[0175] The speed and acceleration estimation unit 81 estimates the speed and acceleration of the aircraft by referring to the trajectory data 37 for a recent past period, for example, several seconds. The aircraft position prediction unit 82 predicts the aircraft position based on the aircraft position calculated at the immediately previous time point and the estimated speed and acceleration. The trajectory update period is set to T seconds (for example, approximately 1 second), and the current time is set to t. The speed and acceleration are estimated at the immediately previous time point (tT), and the aircraft position at the current time t is predicted using the estimated speed and acceleration. The second aircraft position candidate extraction unit 83 extracts second aircraft position candidates from the plot based on the predicted aircraft position. The second aircraft position calculation unit 84 calculates the second aircraft position from the second aircraft position candidates. The aircraft position calculation unit 18E operates in the same manner as the aircraft position calculation unit 18. However, the aircraft position calculated by the aircraft position calculation unit 18E is set to the first aircraft position. The aircraft position integration unit 85 calculates the aircraft position at the current time t based on the second aircraft position based on the prediction and the first aircraft position calculated in the same manner as in the first embodiment. The calculation control unit 86 controls the operations of the aircraft position candidate extraction unit 17 , the aircraft position calculation unit 18 E, the second aircraft position candidate extraction unit 83 , the second aircraft position calculation unit 84 , and the aircraft position integration unit 85 .

[0176] The data memory unit 11E also has an estimated speed 55, an estimated acceleration 56, a predicted aircraft position 57, a first speed threshold 58, a second speed threshold 59, a first acceleration threshold 60, a second acceleration threshold 61, a first aircraft position 62, a distance to predicted position 63, a minimum distance to predicted position 64, a ratio to minimum 65, an upper limit value of the ratio to minimum 66, a second aircraft position candidate 67, a number of second aircraft position candidates 68, a second aircraft position 69, and data for calculating the internal division ratio 70.

[0177] The estimated speed 55 and the estimated acceleration 56 are data that respectively store the speed and acceleration estimated by the speed / acceleration estimation unit 81. The predicted aircraft position 57 is data that stores the aircraft position predicted by the aircraft position prediction unit 82. The first speed threshold 58 and the second speed threshold 59 are thresholds for the estimated speed used to determine the aircraft position from the first aircraft position calculated by the aircraft position calculation unit 18E and the second aircraft position calculated by the second aircraft position calculation unit 84. The second speed threshold 59 is set to be equal to or less than the first speed threshold 58. The first acceleration threshold 60 and the second acceleration threshold 61 are thresholds for the estimated acceleration used to determine the aircraft position from the first aircraft position calculated by the aircraft position calculation unit 18E and the second aircraft position calculated by the second aircraft position calculation unit 84. The second acceleration threshold 61 is set to be equal to or less than the first acceleration threshold 60.

[0178] The first aircraft position 62 is data that stores the first aircraft position, which is the aircraft position calculated by the aircraft position calculation unit 18E. The distance to predicted position 63 is data that stores the distance between each plot and the predicted aircraft position (distance to predicted position). The minimum distance to predicted position 64 is data that stores the distance between each plot P j The minimum ratio 65 is the minimum value of the predicted position distance of each plot P j The minimum ratio upper limit 66 is the value obtained by dividing the predicted position distance of each plot P by the minimum predicted position distance. j The second aircraft position candidate 67 is an aircraft position candidate extracted by the second aircraft position candidate extraction unit 83 based on the distance to predicted position. The number of second aircraft position candidates 68 is the number of second aircraft position candidates 67 extracted by the second aircraft position candidate extraction unit 83. The second aircraft position is an aircraft position calculated by the second aircraft position calculation unit 84 based on the second aircraft position candidate. The second aircraft position 69 is data for storing the second aircraft position. The internal division ratio calculation data 70 is data for storing data used when calculating the internal division ratio, which is a parameter used by the aircraft position integration unit 85 to determine the aircraft position from the first aircraft position and the second aircraft position.

[0179] Define the following variables: ve: the velocity vector of the aircraft 4 estimated by the velocity / acceleration estimation unit 81. The estimated velocity Ve is stored as the estimated velocity 55. ae: the acceleration vector of the aircraft 4 estimated by the speed / acceleration estimation unit 81. The estimated acceleration ae is stored as the estimated acceleration 56. Pe: The position of the aircraft 4 predicted by the aircraft position prediction unit 82. Expressed as Pe=(xe, ye, ze). The predicted aircraft position Pe is stored as the predicted aircraft position 57. vH: a threshold value to be compared with the absolute value |ve| of the estimated speed ve. This is called the first speed threshold value. The first speed threshold value vH is stored as the first speed threshold value 58. vL: a threshold value to be compared with the absolute value |ve| of the estimated speed ve. This is called the second speed threshold value. vL≦vH. The second speed threshold value vL is stored as the second speed threshold value 59. aH: a threshold value to be compared with the absolute value |ae| of the estimated acceleration ae. This is called the first acceleration threshold value. The first acceleration threshold value aH is stored as the first acceleration threshold value 60. aL: a threshold value to be compared with the absolute value |ae| of the estimated acceleration ae. This is called the second acceleration threshold value. aL≦aH. The second acceleration threshold value aL is stored as the second acceleration threshold value 61.

[0180] P p1 : This is the aircraft position calculated by the aircraft position calculation unit 18E. It is called the first aircraft position. P p1 = (xp1, yp1, zp1). The first aircraft position P p1 is stored as the first aircraft position 62. P p2 : The aircraft position calculated by the second aircraft position calculation unit 84. This is called the second aircraft position. P p2 = (xp2, yp2, zp2). The second aircraft position P p2 is stored as the second aircraft position 69. Le(j): Each plot P j and the predicted aircraft position Pe. This is called the distance to predicted position. The distance to predicted position Le(j) is stored as the distance to predicted position 63. Lemin: Each plot P jThis is the minimum value of the predicted position distance Le(j). It is called the minimum predicted position distance. The minimum predicted position distance Lemin is stored as the minimum predicted position distance 64. βe(j): Each plot P j The minimum ratio βe(j) is calculated by dividing the predicted position distance Le(j) by the minimum predicted position distance Lemin. The minimum ratio βe(j) is stored as the minimum ratio 65. βemax: a constant to be compared with the minimum ratio βe(j). This is called the minimum ratio upper limit value. The minimum ratio upper limit value βemax is stored as the minimum ratio upper limit value 66. η2(j): Plot P j is the second aircraft position candidate. If η2(j)=1, plot P j is the second aircraft position candidate. If η2(j)=0, the plot Pj is not the second aircraft position candidate. η2(j) is stored as the second aircraft position candidate 67. Nc2: The number of second aircraft position candidates. This is called the number of second aircraft position candidates. Nc2 is stored as the number of second aircraft position candidates 68. γ(|ve|, |ae|): 1st aircraft position P p1 and the second aircraft position P p2 From the aircraft position P p This is a parameter used when calculating |ve|. It is called the internal division ratio. The internal division ratio γ(|ve|, |ae|) is determined by the aircraft position integrating unit 85 using the internal division ratio calculation data 70 for the absolute value of the estimated velocity |ve| and the absolute value of the acceleration |ae|.

[0181] The speed / acceleration estimation unit 81 estimates the speed ve and acceleration ae by approximating the aircraft positions at multiple recent points in time stored in the trajectory data 37 with a quadratic curve. The speed ve and acceleration ae are vectors. The aircraft position prediction unit 82 predicts the predicted aircraft position Pe based on the aircraft position calculated at the immediately preceding point in time and the estimated speed ve and acceleration ae. The speed / acceleration estimation unit 81 is a speed / acceleration estimation unit that estimates the speed and acceleration of the aircraft based on past aircraft positions stored in the data storage unit 11E.

[0182] The calculation control unit 86 controls the operations of the aircraft position candidate extraction unit 17, the aircraft position calculation unit 18E, the second aircraft position candidate extraction unit 83, the second aircraft position calculation unit 84, and the aircraft position integration unit 85 based on the absolute value |ve| of the estimated speed and the absolute value |ae| of the acceleration. The calculation control unit 86 controls as follows. In the aircraft monitoring device 1E, 0 < vL < vH and 0 < aL < aH. (A) When |ve| < vL and |ae| < aL, operate the second aircraft position candidate extraction unit 83 and the second aircraft position calculation unit 84. (B) When |ve| > vH or |ae| > aH, operate the aircraft position candidate extraction unit 17 and the aircraft position calculation unit 18E. (C) In other cases, operate the aircraft position candidate extraction unit 17, the aircraft position calculation unit 18E, the second aircraft position candidate extraction unit 83, and the second aircraft position calculation unit 84.

[0183] The second aircraft position candidate extraction unit 83 calculates the distance Le(j) from each plot P j to the predicted position using the following formula. When the aircraft is on the Earth's surface, it is calculated using Equation (92), and when the aircraft is in the air, it is calculated using Equation (93). Le(j)=√((xj - xe) 2 +(yj - ye) 2 ) (92) Le(j)=√((xj - xe) 2 +(yj - ye) 2 +(zj - ze) 2 ) (93)

[0184] The second aircraft position candidate extraction unit 83 obtains the minimum value of the distance Le(j) from each plot P j to the predicted position, and sets the obtained minimum value to Lemin. Lemin = min(Le(1),…,Le(Nb)) (94)

[0185] The second aircraft position candidate extraction unit 83 divides the distance Le(j) from each plot P j to the predicted position by the minimum distance to the predicted position Lemin to calculate the ratio βe(j) to the minimum. βe(j)=Le(j) / Lemin (95)

[0186] The second aircraft position candidate extraction unit 83 compares the ratio to the minimum βe(j) with the minimum ratio upper limit βemax, and generates a plot P j Determine whether to use the second aircraft position candidate. Since βe(j) is a value equal to or greater than 1, βemax is set to 1 or greater. By setting βemax = 1, the plot P with the minimum predicted position distance Lemin is obtained. j Only the position of the aircraft may be selected as the second aircraft position candidate. If βe(j)≦βemax, then η2(j)=1 (96) If βe(j)>βemax, then η2(j)=0 (97)

[0187] The minimum predicted position distance Lemin is the minimum value of the predicted position distance Le(j). The minimum ratio upper limit value βemax is a determined coefficient by which the minimum predicted position distance Lemin, which is the minimum value of the predicted position distance Le(j), is multiplied. Note that Le(j) may be compared with a threshold value without calculating the minimum ratio βe(j). In other words, η2(j) may be determined using the following equations (96A) and (97A) instead of equations (96) and (97). If Le(j)≦βemax*Lemin, then η2(j)=1 (96A) If Le(j)>βemax*Lemin, then η2(j)=0 (97A)

[0188] Equations (96), (97) or (96A), (97A) are used to find the plot P that satisfies the predicted difference distance condition, where the predicted position distance Le(j) is equal to or less than the minimum predicted position distance Lemin multiplied by a predetermined coefficient (βemax). j This means extracting the position of the second aircraft.

[0189] The second aircraft position calculation unit 84 calculates the center of gravity of the second aircraft position candidates as the second aircraft position P p2 The second aircraft position calculation unit 84 calculates the second aircraft position P P2 Calculate the coordinates (xp2, yp2, zp2) of xp2 = (1 / Nc2) * Ση2(j) * xj (98) yp2 = (1 / Nc2) * Ση2(j) * yj (99) zp2 = (1 / Nc2) * Ση2(j) * zj (100) In equations (98) to (100), Σ represents taking the sum from j = 1, …, Nb.

[0190] The aircraft position calculation unit 18E calculates the first aircraft position P as the average of aircraft position candidates P1 xp1 = (1 / Nc) * Ση(j) * xj (101) yp1 = (1 / Nc) * Ση(j) * yj (102) zp1 = (1 / Nc) * Ση(j) * zj (103) In equations (101) to (103), Σ represents taking the sum from j = 1, …, Nb.

[0191] The aircraft position integration unit 85 determines the interpolation ratio γ(|ve|, |ae|) with respect to the absolute value of the speed |ve| and the absolute value of the acceleration |ae|. The aircraft position integration unit 85 uses the interpolation ratio γ(|ve|, |ae|) to calculate the aircraft position P P1 and the second aircraft position P P2 and calculates the aircraft position P P P P = γ * P P1 + (l - γ) * P P2 (104)

[0192] The aircraft position integration unit 85 determines the interpolation ratio γ(|ve|, |ae|) so that the following is satisfied. (1) When |ve| < vL and |ae| < aL, γ = 0 (105) (2) When |ve| > vH or |ae| > aH, γ = 1 (106) (3) In other cases, 0 ≤ γ ≤ 1 (107)

[0193] ​​If the absolute value |ve| of the estimated velocity in (1) above is smaller than the second velocity threshold vL and the absolute value |ae| of the estimated acceleration is smaller than the second acceleration threshold aL, this means that the aircraft position is determined based on the second aircraft position candidate. The second aircraft position candidate is determined based on the predicted aircraft position Pe, so determining the aircraft position based on the second aircraft position candidate means determining the aircraft position with emphasis on the predicted aircraft position Pe.

[0194] In the above (2), if |ve| is greater than the first velocity threshold vH, or |ae| is greater than the first acceleration threshold aH, the aircraft position is determined based on the aircraft position candidate. The aircraft position candidate is calculated by placing emphasis on the plot based on the reception time actually measured at each receiving station.

[0195] In the other cases of (3) above, the aircraft position is determined based on the aircraft position candidate and the second aircraft position candidate. P1 and the second aircraft position P P2 Aircraft position P is on the line connecting P This means calculating

[0196] In other cases, the internal ratio γ(|ve|, |ae|) needs to be determined so that the following inequality is satisfied: (a) vH≧|ve1|>|ve2|≧vL, aL≧|ae|≧0 1≧γ(|ve1|, |ae|)≧γ(|ve2|, |ae|)≧0 (108) (b) vH≧|ve1|>|ve2|≧0, aH≧|ae|≧aL 1≧γ(|ve1|, |ae|)≧γ(|ve2|, |ae|)≧0 (109) (c) vL ≥ |ve| ≥ 0, aH ≥ |ae1| > |ae2| ≥ aL. 1≧γ(|ve|, |ae1|)≧γ(|ve|, |ae2|)≧0 (110) (d) vH ≥ |ve| ≥ vL, aH ≥ |ae1| > |ae2| ≥ 0. 1≧γ(|ve|, |ae1|)≧γ(|ve|, |ae2|)≧0 (111)

[0197] The above (a) is a case where the absolute value of the estimated velocity |ve| is equal to or less than the first velocity threshold vH and equal to or greater than the second velocity threshold vL, and the absolute value of the estimated acceleration |ae| is equal to or less than the second acceleration threshold aL, the first aircraft position P P1 and the second aircraft position P P2 On the line segment connecting |ae| and |ve|, if |ae| is the same, the closer |ve| is to vH, the closer the first aircraft position P P1 Aircraft position P is close to P This means calculating

[0198] The above (b) is when |ve| is equal to or less than vH, and |ae| is equal to or less than aH and equal to or greater than aL, the first aircraft position P P1 and the second aircraft position P P2 On the line segment connecting |ae| and |ve|, if |ae| is the same, the closer |ve| is to vH, the closer the first aircraft position P P1 Aircraft position P is close to P This means calculating

[0199] The above (c) is when |ve| is equal to or less than vL, and |ae| is equal to or less than aH and equal to or greater than aL, the first aircraft position P P1 and the second aircraft position P P2 On the line segment connecting |ve| and |ae|, if |ve| is the same, the closer |ae| is to aH, the closer the first aircraft position P P1 Aircraft position P is close to P This means calculating

[0200] The above (d) is the case where |ve| is equal to or less than vH and equal to or greater than vL, and |ae| is equal to or less than aH, the first aircraft position P P1 and the second aircraft position P P2 On the line segment connecting the two, if |ve| is the same, the closer |ae| is to aH, the closer the first aircraft position P P1 Aircraft position P is close to P This means calculating

[0201] The aircraft position integrating unit 85 determines the interior division ratio γ(|ve|, |ae|) as shown in FIG. 30. FIG. 30 is a diagram illustrating an example of the interior division ratio determined by the aircraft position integrating unit included in the aircraft monitoring device according to the fourth embodiment. FIG. 30 illustrates a case where a line (equal interior division ratio line) that is a set of points of the absolute value |ve| of the velocity and the absolute value |ae| of the acceleration where the interior division ratio γ becomes constant is parallel to the |ve| axis or the |ae| axis. FIG. 30(A) illustrates the equal interior division ratio line. FIG. 30(B) illustrates the change in γ with respect to a change in |ve| when |ae| satisfies aL > |ae| ≧ 0. Within the range of vL ≦ |ve| ≦ vH, γ changes linearly with a change in |ve| within the range of 0 ≦ γ ≦ 1. FIG. 30(C) illustrates the change in γ with respect to a change in |ae| when |ve| satisfies vL > |ve| ≧ 0. In the range of aL≦|ae|≦aH, γ changes linearly in the range of 0≦γ≦1 with respect to the change in |ae|.

[0202] The predicted aircraft position Pe is the position of the aircraft 4 predicted based on the past aircraft positions 36 stored in the data storage unit 11. The aircraft position prediction unit 82 is a moving object position prediction unit that calculates the predicted aircraft position Pe. The predicted position distance Le(j) is calculated by plotting P j The second aircraft position candidate is a plot P whose predicted difference distance satisfies the predetermined predicted difference distance condition. j The second moving object position candidate is a second moving object position candidate that is expressed by the following equations: (96), (97) or (96A), (97A) In the aircraft monitoring device 1E, the determined prediction difference distance condition is a condition expressed by the following equations: (96), (97) or (96A), (97A). The second aircraft position candidate extraction unit 83 is a second moving object position candidate extraction unit that extracts the second moving object position candidate.

[0203] In the aircraft monitoring device 1E, the aircraft position P P The moving object position calculation unit that calculates the first aircraft position P is composed of an aircraft position calculation unit 18E, a second aircraft position calculation unit 84, and an aircraft position integration unit 85. P1is the first moving body position, which is the aircraft position calculated by the aircraft position calculation unit 18E based on the aircraft position candidate when |ve| is greater than vH or |ae| is greater than aH. P2 is the second moving body position, which is the aircraft position calculated by the second aircraft position calculation unit 84 based on the second aircraft position candidate when |ve| is smaller than vL and |ae| is smaller than aL.

[0204] The aircraft position integrating unit 85 determines the internal division ratio γ(|ve|, |ae|) so that it is continuous at the boundaries of other cases, i.e., |ve|=vL, |ve|=vH, |ae|=aL, and |ae|=aH. The internal division ratio γ(|ve|, |ae|) may be determined so that it is discontinuous at any of |ve|=vL, |ve|=vH, |ae|=aL, and |ae|=aH. When vH=vL, either γ=0 or γ=1 may be determined at the boundaries of other cases, i.e., |ve|=vH=vL. When aH=aL, either γ=0 or γ=1 may be determined at the boundaries of other cases, i.e., |ae|=aH=aL.

[0205] 31 is a flowchart for explaining the overall operation of the aircraft monitoring device according to the fourth embodiment. The differences between FIG. 31 and FIG. 4 in the first embodiment will be explained. In step S03E, the aircraft monitoring device 1 receives the response signal reception data and calculates the aircraft position P P In step S04, the next step after S03E, the aircraft monitoring device 1E estimates the speed and acceleration of the aircraft from the trajectory. In step S05, the aircraft monitoring device 1E predicts the aircraft's position at the next time point from the estimated speed and acceleration. After S05 is executed, the process returns to S01.

[0206] 32, the aircraft monitoring device 1E receives the response signal reception data and detects the aircraft position P P32 is a flowchart illustrating the process by which an aircraft monitoring device according to the fourth embodiment receives response signal reception data, determines the aircraft position, and updates the trajectory. The differences between FIG. 32 and FIG. 5 in the first embodiment will be described below. In step S19E, the aircraft position and trajectory are calculated based on the response signal reception data of the selected aircraft ID, the predicted aircraft position, the estimated speed, and the estimated acceleration.

[0207] The process in which the aircraft monitoring device 1E obtains the aircraft position and updates the trajectory will be described with reference to Fig. 33. Fig. 33 is a flowchart illustrating the process in which the aircraft monitoring device according to embodiment 4 obtains the aircraft position based on the plot and the predicted aircraft position and updates the trajectory. The differences between Fig. 33 and Fig. 6 in the first embodiment will be described.

[0208] Step S43 is added after S24. In S43, the calculation control unit 86 checks whether |ve|≦vL and |ae|≦aL are true. If |ve|≦vL and |ae|≦aL are not true (NO in S43), the process proceeds to S25. Proceeding to S25 means that the calculation control unit 86 activates the aircraft position candidate extraction unit 17. In S25, the aircraft position candidate extraction unit 17 extracts the plot P whose adjacent distance index, calculated as the average of a predetermined number of adjacent distances from the smallest, is equal to or less than the upper limit. j In step S26E, the aircraft position calculation unit 18E extracts the first aircraft position P from the aircraft position candidates. P1 The first aircraft position calculation unit 18E calculates the center of gravity of the aircraft position candidates as the first aircraft position P P1 Let's say.

[0209] Steps S44 and onward are added after S26E. In S44, the calculation control unit 86 checks whether |ve| ≧ vH or |ae| ≧ aH is true. If |ve| ≧ vH or |ae| ≧ aH is not true (NO in S44), the process proceeds to step S45. If |ve| ≦ vL and |ae| ≦ aL are true (YES in S43), the process also proceeds to S45. Proceeding to S45 means that the calculation control unit 86 activates the second aircraft position candidate extraction unit 83.

[0210] In S45, the second aircraft position candidate extraction unit 83 extracts the position candidate of each plot P j The minimum ratio βe(j), which is the ratio of the minimum value Lemin of the predicted position distance Le(j), which is the distance to the predicted aircraft position Pe, is equal to or less than the minimum ratio upper limit βemax. j In step S46, the second aircraft position candidate calculation unit 84 extracts the second aircraft position P P2 The second aircraft position candidate calculation unit 84 calculates the center of gravity of the second aircraft position candidates as the second aircraft position P P2 After S46 is executed and if |ve|≧vH or |ae|≧aH is established (NO in S44), the process proceeds to step S47.

[0211] In step S47, the aircraft position integrating unit 85 determines the interior division ratio γ as shown in Fig. 30 based on the absolute value |ve| of the estimated velocity and the absolute value |ae| of the acceleration. In step S48, the aircraft position integrating unit 85 determines the first aircraft position P P1 and the second aircraft position P P2 The aircraft position P is the point that divides the line segment connecting P Determine.

[0212] Referring to FIG. 34, the second aircraft position candidate extraction unit 83 extracts the plot P j 34 is a flowchart illustrating processing by a second aircraft position candidate extraction unit included in the aircraft monitoring device according to the fourth embodiment to extract second aircraft position candidates from the plot.

[0213] In step S111, the second aircraft position candidate extraction unit 83 extracts the position of each plot P j In step S112, the second aircraft position candidate extraction unit 83 calculates the predicted position distance Le(j) from all the plots P j In step S113, the second aircraft position candidate extraction unit 83 calculates the minimum value among the predicted position distances Le(j) of each plot P j The minimum ratio βe(j) is calculated by dividing the predicted position distance Le(j) by the minimum predicted position distance Lemin.

[0214] In step S114, j=1 is set. In step S115, it is checked whether βe(j)≦βemax is satisfied. If βe(j)≦βemax is satisfied (YES in S115), the plot P j is the second aircraft position candidate (η2(j)=1). If βe(j)≦βemax is not established (NO in S115), the plot P j is not the second aircraft position candidate (η2(j)=0).

[0215] In step S118, j=j+1 is set. In step S119, it is checked whether j≦Nb. If j≦Nb is not satisfied (NO in S119), all plots P j Since it has been checked whether j is the second aircraft position candidate, the process ends. If j≦Nb (YES in S119), the process returns to S115.

[0216] 35 to 37 will be used to explain an example in which the aircraft monitoring device 1E determines an aircraft position candidate, a second aircraft position candidate, and an aircraft position from a plot. FIG. 35 is a diagram showing an aircraft position candidate and an aircraft position determined by the aircraft monitoring device 1E when the speed or acceleration is high. FIG. 36 is a diagram showing a second aircraft position candidate and an aircraft position determined by the aircraft monitoring device 1E when the speed and acceleration are low. FIG. 37 is a diagram showing an aircraft position candidate, a second aircraft position candidate, and an aircraft position determined by the aircraft monitoring device 1E when the speed and acceleration are intermediate values.

[0217] In Figure 35 and other figures, the predicted aircraft position 97 is shown as a square (□). In Figure 35, the speed of the aircraft is high, so the end points of the trajectory 92 and the predicted aircraft position 97 are far apart. When the speed or acceleration is high, the aircraft monitoring device 1E extracts aircraft position candidates in the same way as the aircraft monitoring device 1, and calculates the aircraft position 94 as the average of the aircraft position candidates. In Figure 35, the plot 90, which is the aircraft position candidate, is represented by a black circle. The aircraft position 94 is represented by a diamond (◇). By calculating the aircraft position 94, the updated trajectory 98 is shown by a dashed line. The trajectory 98 is a curve that smoothly connects the end points of the trajectory 90 and the aircraft position 94.

[0218] In Figure 36, because the aircraft speed and acceleration are small, the endpoints of the trajectory 92 and the predicted aircraft position 97 are close to each other. When a second aircraft position candidate is extracted for the predicted aircraft position 97 by setting the upper ratio limit value βmax = 2, two plots 90 can be extracted. The plot 90, which is the second aircraft position candidate, is represented by a double circle (◎). When the aircraft speed and acceleration are small, the aircraft monitoring device 1E calculates the aircraft position 99 as the average of the second aircraft position candidates. The aircraft position 99 is represented by a diamond (◇). The updated trajectory 98 connecting the aircraft position 99 and the endpoints of the trajectory 92 is drawn close to the line extending the trajectory 92.

[0219] In Figure 37, the aircraft speed and acceleration are values ​​between those in Figure 35 and Figure 36. The aircraft monitoring device 1E calculates a first aircraft position 100, which is the average of the aircraft position candidates, and a second aircraft position 101, which is the average of the second aircraft position candidates. The aircraft monitoring device 1E calculates an aircraft position 102 on the line segment connecting the first aircraft position 100 and the second aircraft position 101. The plot 90, which is an aircraft position candidate, is represented by a black circle, and the plot 90, which is an aircraft position candidate and also a second aircraft position candidate, is represented by a double circle with a black circle inside. The first aircraft position 100 is represented by a black triangle (▲), and the second aircraft position 101 is represented by a white triangle (△). The aircraft position 102 is represented by a diamond (◇).

[0220] The aircraft monitoring device 1E can also determine the aircraft position at a position close to the line extending the trajectory, similar to the aircraft monitoring device 1. The aircraft monitoring device 1E transmits a response signal from the aircraft 4 to each receiving station 3. j The time of reception and each receiving station 3 j By using this position data, the aircraft position can be determined with reduced variation no matter where the aircraft 4 is located. The aircraft's trajectory can also be made to be a natural curve.

[0221] When the absolute value of the velocity and the absolute value of the acceleration are small, the aircraft monitoring device 1E detects the aircraft position P at a position close to the predicted aircraft position Pe. P When the absolute value of the velocity or the absolute value of the acceleration is large, the aircraft monitoring device 1E can determine the plot P j Plot P excluding j Based on the aircraft position P P In other cases, the predicted aircraft position Pe and the isolated plot P j Plot P excluding j Based on the aircraft position P P can be decided.

[0222] The second aircraft position candidate extracted based on the predicted aircraft position Pe may be extracted using a predicted difference distance condition that takes into account not only that the minimum ratio βe(j) is equal to or less than an upper limit value, but also that the predicted position distance Le(j) is equal to or less than an upper limit value.

[0223] The second aircraft position candidate calculation unit may calculate the center of the smallest circle that encompasses all second aircraft position candidates as the aircraft position when the aircraft is on the Earth's surface, and may calculate the center of the smallest sphere that encompasses all second aircraft position candidates as the aircraft position when the aircraft is in the air.

[0224] First variant. The first modification of the fourth embodiment is modified from the fourth embodiment in the following two respects. (d) A second aircraft position candidate is extracted using a prediction difference distance condition that also includes a condition that the distance to the predicted position Le(j) is equal to or less than an upper limit value. (E) The line (equal internal division ratio line) where the internal division ratio γ is constant on a two-dimensional plane of the absolute value of the estimated velocity |ve| and the absolute value of the acceleration |ae| is made to have an elliptical shape.

[0225] The functional configuration of an aircraft monitoring device 1F according to a first modified example of the fourth embodiment will be described with reference to Fig. 38. Fig. 38 is a block diagram illustrating the functional configuration of an aircraft monitoring device according to a first modified example of the fourth embodiment. Regarding Fig. 38, differences from Fig. 27 in the case of the fourth embodiment will be described. Compared to the aircraft monitoring device 1E, the data storage unit 11F, the second aircraft position candidate extraction unit 83F, and the aircraft position integration unit 85F of the aircraft monitoring device 1F have been changed.

[0226] The data storage unit 11F has changed the internal division ratio calculation data 70F. The data storage unit 11F also has an upper limit value 71 of the distance to predicted position. The internal division ratio calculation data 70F has data for the aircraft position integrating unit 85F to calculate the internal division ratio γ as shown in FIG. 39. The aircraft position integrating unit 85F calculates the internal division ratio γ as shown in FIG. 39 using the internal division ratio calculation data 70F. The upper limit value 71 of the distance to predicted position is an upper limit value compared with the distance to predicted position Le(j) used when extracting a second aircraft position candidate.

[0227] Fig. 39 is a diagram illustrating an example of an interior division ratio determined by the aircraft position integration unit 85F of the aircraft monitoring device 1F. Fig. 39(A) illustrates an equal interior division ratio line. Fig. 39(B) illustrates the change in γ with respect to a change in |ve| when |ae|=0. Fig. 39(C) illustrates the change in γ with respect to a change in |ae| when |ve|=0.

[0228] To explain the processing of the shape and aircraft position integrating unit 85F in FIG. 39, the following variables are defined. αv: A constant that divides the absolute value of the estimated velocity |ve|. αa: A constant used to divide the absolute value of the estimated acceleration |ae|. ρ(|ve|, |ae|): A value calculated so that |ve| and |ae| form an elliptical shape. This is called the pseudo diameter. The internal ratio γ is expressed as a linear function of the pseudo diameter ρ. ρ L : Maximum value of pseudo diameter ρ when the internal division ratio γ=0.

[0229] To make the isointerval ratio line elliptical, the pseudo-diameter ρ is calculated using the following formula: ρ(|ve|, |ae|)=√((|ve| / αv) 2 +(|ae| / αa) 2 ) (112) The internal division ratio γ is calculated from the pseudo diameter ρ as follows: ρ≧1, γ=1 (113) 1>ρ>ρ L So, γ=(ρ-ρ L ) / (1-ρ L ) (114) ρ L ≧ρ, γ=0 (115)

[0230] αv, αa, ρ so that equations (105) and (106) hold. L is determined so that the following equation is satisfied. From FIG. 39, it can be seen that equations (116) to (118) must be satisfied. αv≦vH (116) αa≦aH (117) ρ L ≧√((vL / αv) 2 +(aL / αa) 2 ) (118)

[0231] The aircraft position integrating unit 85F calculates the pseudo diameter ρ using equation (112). The aircraft position integrating unit 85F calculates the interior division ratio γ using one of equations (113) to (115) depending on the value of ρ.

[0232] The second aircraft position candidate extraction unit 83F will be described. The second aircraft position candidate extraction unit 83F also uses the following variables. Lemax: An upper limit value to be compared with the distance to predicted position Le(j). This is called the upper limit value of the distance to predicted position. The upper limit value Lemax of the distance to predicted position is stored as the upper limit value 71 of the distance to predicted position.

[0233] The second aircraft position candidate extraction unit 83F extracts the plot P under the following conditions: j Determine whether to select the second aircraft position candidate. If βe(j)=1, then η2(j)=1 (119) If βe(j)≦βemax and Le(j)≦Lemax, then η2(j)=1 (120) If βe(j)>βemax, η2(j)=1 (121) If βe(j)>1 and Le(j)>Lemax, then η2(j)=1 (122)

[0234] Compared with equation (96), the above equation (120) adds the AND condition "Le(j)≦Lemax". This condition is used when the minimum predicted position distance Lemin is large, and the plot P is far from the predicted aircraft position Pe. j This is the condition to prevent the extraction of P as the second aircraft position candidate. j Even if "Le(j)>Lemax", the equation (119) is provided so that the second aircraft position candidate can be extracted. j is always extracted as the second aircraft position candidate. If no second aircraft position candidate can be extracted, the second aircraft position P p2 The aircraft position integration unit 85F cannot determine the aircraft position P p2 It becomes impossible to calculate. Equations (121) and (122) are written as cases where equations (119) and (120) are not satisfied.

[0235] Without calculating the minimum ratio βe(j), plot P under the following conditions j may be determined as the second aircraft position candidate. When Le(j)=Lemin, η2(j)=1 (119A) If Le(j)≦βemax*Lemin and Le(j)≦Lemax, η2(j)=1 (120A) If Le(j)>βemax*Lemin, η2(j)=1 (121A) If Le(j)>Lemin and Le(j)>Lemax, η2(j)=1 (122A)

[0236] The following equation (120B) may be used instead of equation (120A): The following equation (122B) may be used instead of equation (122A): If Le(j)≦min(βemax*Lemin, Lemax), then η2(j)=1 (120B) If Le(j)>min(Lemin, Lemax), then η2(j)=1 (122B)

[0237] The predicted position distance upper limit value Lemax is a determined predicted difference distance upper limit value. Equations (119) to (122), or equations (119A) to (122A), or equations (119A), (120B), (121A), and (122B) represent the predicted difference distance condition that the predicted position distance Le(j) has a minimum value, or the predicted position distance Le(j) is equal to or less than the predicted position distance upper limit value Lemax and equal to or less than the value obtained by multiplying the minimum predicted position distance Lemin by a determined coefficient (βemax).

[0238] The aircraft monitoring device 1F operates in the same manner as the aircraft monitoring device 1E, and provides the same effects. In the aircraft monitoring device 1F, since there are no corners in the equal interior ratio lines, the aircraft position changes more smoothly with respect to changes in the absolute value of the velocity and the absolute value of the acceleration. In the aircraft monitoring device 1F, the second aircraft position P p2 can be calculated closer to the predicted aircraft position Pe.

[0239] Embodiment 5. The aircraft monitoring device of embodiment 5 is a modification of embodiment 4 in that it adds an exclusion process that excludes plots whose distance from the predicted aircraft position is greater than a threshold from the targets for extracting the first aircraft position candidate and the second aircraft position candidate.

[0240] The functional configuration of the aircraft monitoring device 1G according to the fifth embodiment will be described with reference to FIG. 40. FIG. 40 is a block diagram illustrating the functional configuration of the aircraft monitoring device according to the fifth embodiment. Regarding FIG. 40, differences from FIG. 29 for the aircraft monitoring device 1E will be described. The aircraft monitoring device 1G has a plot exclusion unit 87. The plot exclusion unit 87 excludes plots whose distance from the predicted aircraft position Pe is equal to or greater than a predetermined distance from the plots for extracting the first aircraft position candidate and the second aircraft position candidate. In the aircraft monitoring device 1G, the data storage unit 11G, the aircraft position candidate extraction unit 17G, and the second aircraft position candidate extraction unit 83G have been modified. The data storage unit 11G also stores data used by the plot exclusion unit 87 and data resulting from processing. The aircraft position candidate extraction unit 17G and the second aircraft position candidate extraction unit 83G process plots not excluded by the plot exclusion unit 87.

[0241] The data storage unit 11G also has an exclusion distance 72, an exclusion plot 73, and a non-exclusion plot count 73. The exclusion distance 72 is data that stores a threshold value that is compared with the distance to the predicted position Le(j). The exclusion plot 73 is data that represents plots that have a distance to the predicted position Le(j) greater than the threshold value and have been excluded by the plot exclusion unit 87. The non-exclusion plot count 74 is data that stores the number of plots that have not been excluded.

[0242] To explain the plot exclusion unit 87, the following variables are defined: Leth: A threshold value to be compared with the distance to the predicted position Le(j). This is called the exclusion distance. This exclusion distance is stored as the exclusion distance 72. This can be changed by the user within a range of about several tens of meters to 100 meters. ηe(j): indicates whether the plot has been excluded by the plot exclusion unit 87. Whether a plot has been excluded or not is called the exclusion state. ηe(j)=1 indicates a plot that has not been excluded. ηe(j)=0 indicates a plot that has been excluded. The exclusion state ηe(j) is stored as the excluded plot 73. Ne: The number of plots that are not excluded. This is called the number of non-excluded plots. The number of non-excluded plots Ne is stored as the number of non-excluded plots 74.

[0243] The data storage unit 11G has changed the adjacent distance 29G. The adjacent distance 29G stores the adjacent distance L(j, k) between plots that have not been excluded. The aircraft position candidate extraction unit 17 does not calculate the adjacent distance between the excluded plot and other plots. Plot P j or Plot P k is excluded, a value that is an order of magnitude larger than the actual distance, such as 999.9, is stored in the adjacent distance 29G.

[0244] The plot exclusion unit 87 calculates the distance Le(j) relative to the predicted position. The plot exclusion unit 87 compares the distance Le(j) relative to the predicted position with the exclusion distance Leth, and excludes each plot P j Set the exclusion state ηe(j). If Le(j)>Leth, then ηe(j)=0 (123) If Le(j)≦Leth, then ηe(j)=1 (124)

[0245] The exclusion distance Leth is a predetermined first distance. The plot exclusion unit 87 excludes plots P whose distances to the predicted position Le(j) are greater than the exclusion distance Leth. j is a moving object position exclusion unit that does not consider the position of the aircraft as a candidate.

[0246] The aircraft position candidate extraction unit 17G refers to the exclusion state ηe(j) and calculates the adjacent distance L(j, k) between the plots that have not been excluded. The aircraft position candidate extraction unit 17G refers to the adjacent distances L(j, k), and sorts the adjacent distances L(j, k) in ascending order to generate the ordered distance Lm(j, q).

[0247] The number m of the top plots is set to be smaller than the number of non-exclusion plots Ne. Therefore, the aircraft position candidate extraction unit 17G calculates the adjacent distance index Lav(j) by the formula (41) in the same way as the aircraft position candidate extraction unit 17.

[0248] The aircraft position candidate extraction unit 17G extracts the unexcluded plot P j Regarding the plot P j The adjacent distance index Lav(j) is compared with the index upper limit Lmax, and the plot P j Determine whether to consider the position of the aircraft as a candidate. If ηe(j)=1 and Lav(j)≦Lmax, then η(j)=1 (125) If ηe(j)=0 or Lav(j)>Lmax, then η(j)=0 (126)

[0249] The second aircraft position candidate extraction unit 83G extracts the position of each plot P j In other respects, the second aircraft position candidate extraction unit 83G operates in the same manner as the second aircraft position candidate extraction unit 83.

[0250] The operation will be described. Referring to Fig. 41, the process in which the aircraft monitoring device 1G determines the aircraft position and updates the trajectory will be described. Fig. 41 is a flowchart explaining the process in which the aircraft monitoring device according to embodiment 5 determines the aircraft position based on the plot and the predicted aircraft position and updates the trajectory. Regarding Fig. 41, the differences from Fig. 33 in the case of embodiment 4 will be described.

[0251] Steps S49 and S50 are added between S24 and S43. In S49, the plot exclusion unit 87 calculates the distance Le(j) relative to the predicted position. In S50, the plot exclusion unit 87 excludes plots P whose distance Le(j) relative to the predicted position is greater than the exclusion distance Leth. j Exclude.

[0252] In step S25G, the aircraft position candidate extraction unit 17G extracts the unexcluded plot P j Calculate the adjacent distance and select the plot P that is not excluded and whose adjacent distance index is less than the upper limit value by averaging the minimum number of adjacent distances. j are extracted as aircraft position candidates.

[0253] In step S45G, the second aircraft position candidate extraction unit 83G extracts the second aircraft position candidate. j In other respects, the process in S45G is the same as S45.

[0254] Referring to FIG. 42, the aircraft position candidate extraction unit 17G extracts the plot P j 42 is a flowchart illustrating the process of extracting aircraft position candidates from the plot by the aircraft position candidate extraction unit of the aircraft monitoring device according to embodiment 1. The differences between FIG. 42 and FIG. 7 in the case of the aircraft position candidate extraction unit 17 will be described.

[0255] In step S31G, the aircraft position candidate extraction unit 17G extracts the two plots P j , P k In step S31G, the adjacent distance L(j, k) relating to the excluded plots is set to a value that is an order of magnitude larger than the actual distance. In step S33G, the aircraft position candidate extraction unit 17G calculates the adjacent distance L(j, k) relating to the excluded plots P j The adjacent distance index Lav(j) is calculated using equation (41).

[0256] In step S35G, it is checked whether ηe(j)=1 and Lav(j)≦Lmax are satisfied. If ηe(j)=1 and Lav(j)≦Lmax are satisfied (YES in S35G), the plot P j is an aircraft position candidate (η(j)=1). If ηe(j)=1 and Lav(j)≦Lmax are not satisfied (NO in S35G), in step S37, the plot P j is not an aircraft position candidate (η(j)=0).

[0257] Referring to FIG. 43, second aircraft position candidate extraction unit 83G extracts the plot P j FIG. 43 is a flowchart illustrating the process of extracting aircraft position candidates from the plot by the aircraft position candidate extraction unit of the aircraft monitoring device according to embodiment 1. Regarding FIG. 43, the differences from FIG. 34 in the case of the second aircraft position candidate extraction unit 83 will be described. Since the distance to predicted position Le(j) has already been calculated, S111 is omitted. Other points are the same.

[0258] An example of how the aircraft monitoring device 1G calculates an aircraft position will be described with reference to Fig. 44. Fig. 44 shows a case in which a plot 90 similar to that in Fig. 35 is calculated, but the trajectory 92 and predicted aircraft position 97 are farther away from the plot 90, which is the aircraft position candidate, than in Fig. 35. Fig. 44 is a diagram showing the aircraft position candidate and aircraft position determined by the aircraft monitoring device 1G when the speed or acceleration is high.

[0259] In Figure 44, a circle with a radius of the exclusion distance Leth centered on the predicted aircraft position 97 is called an exclusion circle 103. The aircraft monitoring device 1G calculates the aircraft position 94 from only the plots 90 that exist on or inside the exclusion circle 103. Therefore, one plot 90 that was extracted as an aircraft position candidate in the case of Figure 35 exists outside the exclusion circle 103, and therefore is not extracted as an aircraft position candidate in Figure 44. The aircraft position 94 is then calculated to be slightly shifted to the upper left in the figure. The updated trajectory 98 is drawn as a curve that smoothly connects the endpoints of the trajectory 92 and the aircraft position 94.

[0260] The aircraft monitoring device 1G can also determine the aircraft position at a position close to the line extending the trajectory, similar to the aircraft monitoring device 1. The aircraft monitoring device 1G transmits a response signal from the aircraft 4 to each receiving station 3. j The time of reception and each receiving station 3 j By using this position data, the aircraft position can be determined with reduced variation no matter where the aircraft 4 is located. The aircraft's trajectory can also be made to be a natural curve.

[0261] Embodiment 6 The aircraft monitoring device according to the sixth embodiment estimates only the speed without estimating the acceleration to predict the aircraft position, and if the speed is low, calculates the aircraft position from a plot that is close to the predicted aircraft position. The aircraft monitoring device 1H according to the sixth embodiment calculates the aircraft position in the same way as the aircraft monitoring device 1 if the aircraft speed is high.

[0262] The functional configuration of an aircraft monitoring device 1H according to embodiment 6 will be described with reference to Fig. 45. Fig. 45 is a block diagram illustrating the functional configuration of an aircraft monitoring device according to embodiment 6. Regarding Fig. 45, differences from Fig. 27 for the aircraft monitoring device 1E will be described. In the aircraft monitoring device 1H, the data storage unit 11H, speed estimation unit 81H, aircraft position prediction unit 82H, aircraft position integrating unit 85H, and calculation control unit 86H have been changed.

[0263] The data storage unit 11H does not have the estimated acceleration 56, the first acceleration threshold value 60, and the second acceleration threshold value 61. The speed estimation unit 81H estimates the speed ve by approximating the aircraft positions at a plurality of adjacent time points stored in the trajectory data 37 with a straight line. The speed ve is a vector. The aircraft position prediction unit 82H predicts the predicted aircraft position Pe based on the aircraft position calculated at the immediately preceding time point and the estimated speed ve.

[0264] The calculation control unit 86H controls the operations of the aircraft position candidate extraction unit 17, the aircraft position calculation unit 18E, the second aircraft position candidate extraction unit 83, the second aircraft position calculation unit 84, and the aircraft position integration unit 85H based on the absolute value |ve| of the estimated speed. The calculation control unit 86H performs the control as follows. (A) When |ve| ≦ vL, the second aircraft position candidate extraction unit 83 and the second aircraft position calculation unit 84 are operated. (B) When |ve| > vH, the aircraft position candidate extraction unit 17 and the aircraft position calculation unit 18E are operated. (C) In other cases, the aircraft position candidate extraction unit 17, the aircraft position calculation unit 18E, the second aircraft position candidate extraction unit 83, and the second aircraft position calculation unit 84 are operated.

[0265] The aircraft position integration unit 85H determines the interpolation ratio γ(|ve|) with respect to the absolute value |ve| of the speed. The aircraft position integration unit 85H uses the interpolation ratio γ(|ve|) to calculate the aircraft position P P1 and the second aircraft position P P2 and calculates the aircraft position P P based on them.

[0266] The aircraft position integration unit 85H determines the interpolation ratio γ(|ve|) so that the following is satisfied. (1) When |ve| < vL, γ = 0 (127) (2) When |ve| > vH, γ = 1 (128) (3) In other cases, 0 ≦ γ ≦ 1 (129)

[0267] If the absolute value of the estimated speed |ve| in (1) above is smaller than the second speed threshold vL, it means that the aircraft position is determined based on the second aircraft position candidate. If |ve| in (2) above is larger than the first speed threshold vH, it means that the aircraft position is determined based on the aircraft position candidate. In other cases in (3) above, it means that the aircraft position is determined based on the aircraft position candidate and the second aircraft position candidate.

[0268] In other cases, the internal ratio γ(|ve|) needs to be determined so that the following inequality is satisfied: (a) vH ≥ |ve1| > |ve2| ≥ vL 1≧γ(|ve1|)≧γ(|ve2|)≧0 (130)

[0269] The above (a) indicates that the first aircraft position P is determined when the absolute value |ve| of the estimated speed is equal to or less than the first speed threshold vH and equal to or greater than the second speed threshold vL. P1 and the second aircraft position P P2 On the line connecting |ve| and vH, the closer |ve| is to vH, the closer the first aircraft position P P1 Aircraft position P is close to P This means calculating

[0270] The aircraft position integrating unit 85H determines the interior division ratio γ(|ve|) as shown in Fig. 46. Fig. 46 is a diagram illustrating an example of the interior division ratio determined by the aircraft position integrating unit 85H possessed by the aircraft monitoring device 1H. Fig. 46 illustrates γ(|ve|) with respect to |ve|. γ changes linearly within the range of 0≦γ≦1 with respect to |ve| within the range of vL≦|ve|≦vH.

[0271] The aircraft monitoring device 1H detects the aircraft position P P The moving object position calculation unit that calculates the first aircraft position P is composed of an aircraft position calculation unit 18E, a second aircraft position calculation unit 84, and an aircraft position integration unit 85H. P1 is the first moving body position, which is the aircraft position calculated by the aircraft position calculation unit 18E based on the aircraft position candidate when |ve| is greater than vH.P2 is the second moving body position, which is the aircraft position calculated by the second aircraft position calculation unit 84 based on the second aircraft position candidate when |ve| is smaller than vL.

[0272] The aircraft position integrating unit 85 determines the internal division ratio γ(|ve|) so that it is continuous at |ve|=vL and |ve|=vH, which are the boundaries for other cases. The internal division ratio γ(|ve|) may be determined so that it is discontinuous at either |ve|=vL or |ve|=vH. When vH=vL, it may be determined to be either γ=0 or γ=1 at |ve|=vH=vL, which are the boundaries for other cases.

[0273] 47 is a flowchart explaining the overall operation of the aircraft monitoring device according to the sixth embodiment. The differences between FIG. 47 and FIG. 31 in the fourth embodiment will be explained. In step S03H, the aircraft monitoring device 1 receives the response signal reception data and calculates the aircraft position P P In step S04H, the next step after S03H, the aircraft monitoring device 1H estimates the aircraft's speed from the trajectory. In step S05H, the aircraft monitoring device 1H predicts the aircraft's position at the next time point from the estimated speed. After S05H is executed, the process returns to S01.

[0274] Referring to FIG. 48, the aircraft monitoring device 1H receives the response signal reception data and detects the aircraft position P P 48 is a flowchart illustrating the process by which an aircraft monitoring device according to embodiment 6 receives response signal reception data, determines the aircraft position, and updates the trajectory. The differences between FIG. 48 and FIG. 32 in the fourth embodiment will be described below. In step S19H, the aircraft position and trajectory are calculated based on the response signal reception data of the selected aircraft ID, the predicted aircraft position, and the estimated speed.

[0275] The process in which the aircraft monitoring device 1H determines the aircraft position and updates the trajectory will be described with reference to Fig. 49. Fig. 49 is a flowchart illustrating the process in which the aircraft monitoring device according to embodiment 6 determines the aircraft position based on the plot and the predicted aircraft position and updates the trajectory. The differences between Fig. 49 and Fig. 33 in embodiment 4 will be described.

[0276] In step S43H, the calculation control unit 86H checks whether |ve|≦vL holds. If |ve|≦vL does not hold (NO in S43H), the process proceeds to S25.

[0277] In step S44H, the calculation control unit 86H checks whether |ve|≧vH is true. If |ve|≧vH is not true (NO in S44H), the process proceeds to step S45. If |ve|≦vL is true (YHS in S43H), the process also proceeds to S45.

[0278] In step S47H, the aircraft position integrating unit 85 determines the interior division ratio γ as shown in FIG. 46 based on the absolute value |ve| of the estimated velocity.

[0279] The aircraft monitoring device 1H can also determine the aircraft position at a position close to the line extending the trajectory, similar to the aircraft monitoring device 1. The aircraft monitoring device 1H transmits a response signal from the aircraft 4 to each receiving station 3. j The time of reception and each receiving station 3 j By using this position data, the aircraft position can be determined with reduced variation no matter where the aircraft 4 is located. The aircraft's trajectory can also be made to be a natural curve.

[0280] When the absolute value of the speed is small, the aircraft monitoring device 1H detects the aircraft position P at a position close to the predicted aircraft position Pe. P When the absolute value of the speed is large, the aircraft monitoring device 1H detects a plot P j Plot P excluding j Based on the aircraft position P P In other cases, the predicted aircraft position Pe and the isolated plot Pj Plot P excluding j Based on the aircraft position P P can be decided.

[0281] The embodiments can be freely combined, modified, or some of the components can be omitted, or embodiments in which some of the components have been omitted or modified can be freely combined.

[0282] Various aspects of the present disclosure are summarized below as appendices.

[0283] (Appendix 1) a position data storage unit that stores the positions of a plurality of receiving stations that receive signals transmitted by a mobile unit; a reception time acquisition unit that acquires a reception time, which is the time when the receiving station received the signal; a receiving station combination generation unit that generates a number of receiving station combinations, which are combinations of the minimum number of receiving stations that have received the signal for positioning, that is, three when the moving object is on the Earth's surface and four when the moving object is in the air, the number of combinations being either a predetermined number or the number of all possible combinations, whichever is smaller; an individual calculated position calculation unit that calculates, for each of the receiving station combinations, an individual calculated position that is a position from which the moving body transmitted the signal, at which each of the receiving stations included in the receiving station combination receives the signal at the reception time, based on the positions of each of the receiving stations included in the receiving station combination and the reception time; a mobile body position candidate extraction unit that extracts mobile body position candidates that are individual calculation positions that satisfy a predetermined neighboring distance condition determined using an adjacent distance set of the individual calculation positions, which is a set of a predetermined first number of adjacent distances that are consecutively arranged, including the smallest, in a sequence of the adjacent distances that are arranged in ascending order for each of the individual calculation positions, based on an adjacent distance that is a distance between each of the individual calculation positions and another individual calculation position, or that satisfy a predetermined neighboring set condition determined using an adjacent individual calculation position set of the individual calculation position, which is a set of the individual calculation positions that have any of the adjacent distances included in the adjacent distance set; a mobile object monitoring device comprising a mobile object position calculation unit that calculates a mobile object position, which is the position of the mobile object, based on the mobile object position candidate; (Appendix 2) A mobile object monitoring device as described in Appendix 1, wherein the mobile object position candidate extraction unit extracts the individual calculated position as the mobile object position candidate, where the adjacent distance index determined based on the adjacent distance set satisfies the adjacent distance condition. (Appendix 3) A mobile object monitoring device as described in Appendix 2, wherein the mobile object position candidate extraction unit determines the adjacent distance index of the individual calculated position as the sum of the products of each adjacent distance and a first weighting coefficient determined based on the number of adjacent distances included in the adjacent distance set of the individual calculated position, from the smallest in the adjacent distance set. (Appendix 4) The mobile object monitoring device described in Appendix 2, wherein the mobile object position candidate extraction unit determines, as the adjacent distance index of the individual calculation position, the sum of the products of a first weighting coefficient determined based on the ranking of each adjacent distance included in the adjacent distance set of the individual calculation position from the smallest in the adjacent distance set of the other individual calculation position, the adjacent distance index corresponding to the individual calculation position, based on the ranking distance corresponding to the adjacent distance with the other individual calculation position, the ranking distance indicating the ranking of the adjacent distance with the other individual calculation position from the smallest in the adjacent distance set of the other individual calculation position, the adjacent distance index being determined based on the ranking of each adjacent distance included in the adjacent distance set of the individual calculation position from the smallest in the adjacent distance set of the other individual calculation position. (Appendix 5) A mobile object monitoring device as described in any one of Supplementary Note 2 to Supplementary Note 4, wherein the mobile object position candidate extraction unit extracts the individual calculated position where the adjacent distance index is less than or equal to a predetermined index upper limit value as the mobile object position candidate. (Appendix 6) The mobile object monitoring device according to any one of Supplementary Note 2 to Supplementary Note 4, wherein the mobile object position candidate extraction unit extracts, as the mobile object position candidate, an individual calculation position whose to-reference ratio, which is the value obtained by dividing the adjacent distance index of an individual calculation position by a reference adjacent distance index which is the sum of the products of the adjacent distance index of each individual calculation position and a second weighting coefficient which is determined based on the number of the individual calculation positions included in the individual calculation position set, which is a predetermined second number of the individual calculation positions arranged consecutively including the smallest in the sequence of the individual calculation positions arranged in ascending order of the adjacent distance index, is less than or equal to a predetermined ratio upper limit value. (Appendix 7) 5. The mobile object monitoring device according to any one of Supplementary Note 2 to Supplementary Note 4, wherein the mobile object position candidate extraction unit extracts, as the mobile object position candidate, the individual calculated position for which the adjacent distance index is equal to or less than a predetermined index upper limit value, and the individual calculated position for which a to-reference ratio, which is a value obtained by dividing the adjacent distance index of the individual calculated position by a reference adjacent distance index which is the sum of the product of a second weighting coefficient determined based on the number of the individual calculated position in the individual calculated position set, and the adjacent distance index of each of the individual calculated positions, and the reference ratio is equal to or less than a predetermined ratio upper limit value. (Appendix 8) 5. The mobile object monitoring device according to any one of Supplementary Note 2 to Supplementary Note 4, wherein the mobile object position candidate extraction unit extracts, as the mobile object position candidate, an individual calculation position whose adjacent distance index is equal to or less than a predetermined index upper limit value and whose to-reference ratio, which is a value obtained by dividing the adjacent distance index of the individual calculation position by a reference adjacent distance index which is the sum of the products of the adjacent distance index of each individual calculation position and a second weighting coefficient which is determined based on the number of the individual calculation position in the individual calculation position set, the individual calculation position being a predetermined second number of the individual calculation positions arranged consecutively, including the smallest, in the sequence of the individual calculation positions arranged in ascending order of the adjacent distance index, is equal to or less than a predetermined ratio upper limit value. (Appendix 9) the mobile object position candidate extraction unit determines that the own individual calculated position and the other individual calculated position belong to the same group when the own individual calculated position is included in the adjacent individual calculated position set of the other individual calculated position that is the individual calculated position, and A mobile object monitoring device as described in Appendix 1, wherein the mobile object position candidate extraction unit extracts the individual calculated position that satisfies the adjacent set condition of belonging to the group having the largest number of the individual calculated positions belonging to the group as the mobile object position candidate. (Appendix 10) 10. The mobile object monitoring device according to any one of Supplementary Note 1 to Supplementary Note 9, wherein the mobile object position calculation unit calculates an average position of the mobile object position candidates as the mobile object position. (Appendix 11) A mobile object monitoring device as described in any one of Supplementary Note 1 to Supplementary Note 9, wherein the mobile object position calculation unit calculates the center of the smallest circle that encompasses all of the mobile object position candidates as the mobile object position when the mobile object is on the Earth's surface, and calculates the center of the smallest sphere that encompasses all of the mobile object position candidates as the mobile object position when the mobile object is in the air. (Appendix 12) a mobile object position history storage unit that stores past positions of the mobile object over a predetermined period of time; 12. A mobile object monitoring device according to any one of claims 1 to 11, further comprising: a mobile object trajectory generating unit that generates a mobile object trajectory connecting the mobile object positions stored in the mobile object position history storage unit. (Appendix 13) a mobile object position history storage unit that stores past positions of the mobile object over a predetermined period of time; a mobile object position prediction unit that calculates a predicted mobile object position, which is a position of the mobile object predicted based on past mobile object positions stored in the mobile object position history storage unit; a moving object position exclusion unit that excludes the individually calculated positions whose distances from the predicted moving object position are greater than a predetermined first distance from the predicted moving object position as the moving object position candidate. (Appendix 14) a mobile object position history storage unit that stores past positions of the mobile object over a predetermined period of time; a mobile object position prediction unit that calculates a predicted mobile object position, which is a position of the mobile object predicted based on past mobile object positions stored in the mobile object position history storage unit; a speed estimation unit that estimates a speed of the moving object based on past positions of the moving object stored in the moving object position history storage unit; a second moving object position candidate extraction unit that extracts a second moving object position candidate, which is the individually calculated position, where a prediction difference distance, which is a distance between the individually calculated position and the predicted moving object position, satisfies a predetermined prediction difference distance condition; When the absolute value of the speed is greater than a first speed threshold, the moving object position calculation unit calculates the moving object position based on the moving object position candidate; A mobile object monitoring device described in any one of Supplementary Note 1 to Supplementary Note 9, wherein when the absolute value of the speed is smaller than a second speed threshold set to be equal to or less than the first speed threshold, the mobile object position calculation unit calculates the mobile object position based on the second mobile object position candidate. (Appendix 15) A mobile object monitoring device as described in Appendix 14, wherein when the absolute value of the speed is less than the first speed threshold and greater than or equal to the second speed threshold which is set smaller than the first speed threshold, the mobile object position calculation unit calculates the mobile object position based on the mobile object position candidate and the second mobile object position candidate. (Appendix 16) When the absolute value of the speed is equal to or less than the first speed threshold and equal to or greater than the second speed threshold that is set smaller than the first speed threshold, the moving body position calculation unit calculates the moving body position on a line segment connecting a first moving body position that is the moving body position calculated by the moving body position calculation unit based on the moving body position candidate and a second moving body position that is the moving body position calculated by the moving body position calculation unit based on the second moving body position candidate, A mobile object monitoring device as described in Appendix 14, wherein the closer the absolute value of the speed is to the first speed threshold, the closer the mobile object position is to a position not far from the first mobile object position. (Appendix 17) a mobile object position history storage unit that stores past positions of the mobile object over a predetermined period of time; a mobile object position prediction unit that calculates a predicted mobile object position, which is a position of the mobile object predicted based on past mobile object positions stored in the mobile object position history storage unit; a speed estimation unit that estimates a speed of the moving object based on past positions of the moving object stored in the moving object position history storage unit; a speed and acceleration estimation unit that estimates the speed and acceleration of the moving object based on past positions of the moving object stored in the moving object position history storage unit; a second moving object position candidate extraction unit that extracts a second moving object position candidate, which is the individually calculated position, where a prediction difference distance, which is a distance between the individually calculated position and the predicted moving object position, satisfies a predetermined prediction difference distance condition; When the absolute value of the velocity is greater than a first velocity threshold, or when the absolute value of the acceleration is greater than a first acceleration threshold, the moving object position calculation unit calculates the moving object position based on the moving object position candidate, A mobile object monitoring device as described in any one of Supplementary Note 1 to Supplementary Note 9, wherein when the absolute value of the velocity is smaller than a second velocity threshold set to be equal to or smaller than the first velocity threshold, and when the absolute value of the acceleration is smaller than a second acceleration threshold set to be equal to or smaller than the first acceleration threshold, the mobile object position calculation unit calculates the mobile object position based on the second mobile object position candidate. (Appendix 18) A mobile object monitoring device as described in Appendix 17, wherein the mobile object position calculation unit calculates the mobile object position based on the mobile object position candidate and the second mobile object position candidate when the absolute value of the speed is equal to or less than the first speed threshold and the absolute value of the acceleration is equal to or less than the first acceleration threshold and the absolute value of the speed is equal to or greater than the second speed threshold set to be smaller than the first speed threshold, or when the absolute value of the acceleration is equal to or greater than the second acceleration threshold set to be smaller than the first acceleration threshold. (Appendix 19) When the absolute value of the velocity is equal to or less than the first velocity threshold and the absolute value of the acceleration is equal to or less than the first acceleration threshold and the absolute value of the velocity is equal to or greater than the second velocity threshold which is set to be smaller than the first velocity threshold, or when the absolute value of the acceleration is equal to or greater than the second acceleration threshold which is set to be smaller than the first acceleration threshold, the moving body position calculation unit calculates the moving body position on a line segment connecting a first moving body position which is the moving body position calculated by the moving body position calculation unit based on the moving body position candidate and a second moving body position which is the moving body position calculated by the moving body position calculation unit based on the second moving body position candidate, If the absolute value of the velocity is the same, the closer the absolute value of the acceleration is to the first acceleration threshold, the closer the moving object position is to the first moving object position, and A mobile object monitoring device as described in Appendix 17, wherein, if the absolute value of the acceleration is the same, the closer the absolute value of the velocity is to the first velocity threshold, the closer the mobile object position is to a position not far from the first mobile object position. (Appendix 20) A mobile object monitoring device described in any one of Supplementary Note 14 to Supplementary Note 19, wherein the second mobile object position candidate extraction unit extracts the individually calculated position that satisfies the prediction difference distance condition of having a prediction difference distance that is less than or equal to the smallest value among the prediction difference distances of all the individually calculated positions multiplied by a determined coefficient as the second mobile object position candidate. (Appendix 21) A mobile object monitoring device as described in any one of Supplementary Note 14 to Supplementary Note 19, wherein the second mobile object position candidate extraction unit extracts the individually calculated position that satisfies the prediction difference distance condition, that is, the prediction difference distance is the smallest value among the prediction difference distances of all the individually calculated positions, or the prediction difference distance is less than or equal to a predetermined prediction difference distance upper limit value and less than or equal to a value obtained by multiplying the smallest value by a predetermined coefficient, as the second mobile object position candidate. (Appendix 22) a moving object position exclusion unit that excludes the individually calculated positions whose distances from the predicted moving object position are greater than a first distance from the predicted moving object position as the moving object position candidate. (Appendix 23) A mobile object monitoring device described in any one of Supplementary Note 14 to Supplementary Note 22, wherein when the mobile object position calculation unit calculates the mobile object position based on the mobile object position candidates, the average position of the mobile object position candidates is calculated as the mobile object position. (Appendix 24) A mobile object monitoring device as described in any one of Supplementary Note 14 to Supplementary Note 22, wherein when the mobile object position calculation unit calculates the mobile object position based on the mobile object position candidates, if the mobile object is on the Earth's surface, it calculates the center of the smallest circle that encompasses all of the mobile object position candidates as the mobile object position, and if the mobile object is in the air, it calculates the center of the smallest sphere that encompasses all of the mobile object position candidates as the mobile object position. (Appendix 25) A mobile object monitoring device described in any one of Supplementary Note 14 to Supplementary Note 24, wherein when the mobile object position calculation unit calculates the mobile object position based on the second mobile object position candidate, the average position of the second mobile object position candidate is used as the mobile object position. (Appendix 26) A mobile object monitoring device as described in any one of Supplementary Note 14 to Supplementary Note 24, wherein when the mobile object position calculation unit calculates the mobile object position based on the second mobile object position candidates, if the mobile object is on the Earth's surface, the center of the smallest circle that encompasses all of the second mobile object position candidates is calculated as the mobile object position, and if the mobile object is in the air, the center of the smallest sphere that encompasses all of the second mobile object position candidates is calculated as the mobile object position. (Appendix 27) A mobile object monitoring device according to any one of Supplementary Note 13 to Supplementary Note 26, comprising a mobile object trajectory generation unit that generates a mobile object trajectory connecting the mobile object positions stored in the mobile object position history storage unit. [Explanation of symbols]

[0284] 1, 1A, 1B, 1C, 1D, 1E, 1F, 1G, 1H Aircraft monitoring equipment (mobile monitoring equipment), 2 transmitting stations, 31~3 N , 3 j Receiving station, 4. Aircraft (mobile) 5 terrestrial networks, 11, 11A, 11B, 11C, 11D, 11E, 11F, 11G, 11H data storage unit (position data storage unit, mobile object position history storage unit), 12 Network Communications Department, 13 Response signal reception data distribution unit, 14 Reception time data generation unit (reception time acquisition unit), 15 receiving station combination generation unit, 16 Plot calculation unit (individual calculation position calculation unit), 17, 17A, 17B, 17C, 17D, 17G Aircraft position candidate extraction unit (mobile object position candidate extraction unit), 18, 18A, 18E Aircraft position calculation unit (mobile position calculation unit), 19 Trajectory generation unit (moving object trajectory generation unit), 20 receiving station location, 21 Earth surface data, 22 Combinatorial calculations, 23 Response signal reception data, 24 reception time data, 25 calculation modes, 26 receiving station combinations, 27 Maximum number of receiving stations for all combinations 28 plots (individual calculation locations), 29 adjacent distance, 30 ordered distance, 31, 31A adjacent distance index, 32 top numbers, 33, 33C index upper limit, 34 Aircraft position candidates, 35 Number of aircraft position candidates, 36 Aircraft position, 37 trajectory data, 38 weighting factor (first weighting factor), 39 second highest number, 40 Reference Adjacent Distance Indicators, 41 vs. reference ratio, 42 upper limit of ratio, 43 vertex position, 44 minimum radius, 45 pair center distance, 46 weighting factor (second weighting factor), 47 Sequencing number, 48 adjacent ranks, 49 ranking distance, 50 rank distance indicators, 51 Possibility of connection, 52 plot sets, 53 Number of affiliations, 54 candidate set number, 55 estimated speed, 56 Estimated acceleration, 57 predicted aircraft position; 58 Speed ​​first threshold, 59 Speed ​​second threshold, 60 Acceleration first threshold, 61 Second acceleration threshold, 62 1st aircraft position, 63 vs. predicted location distance, 64 Minimum to predicted position distance, 65 to minimum ratio, 66 vs. minimum ratio upper limit, 67 2nd aircraft position candidate, 68 Number of second aircraft position candidates, 69 2nd aircraft position, 70, 70F Data for calculating internal division ratio, 71 Upper limit of distance to predicted position, 72 exclusion distance, 73 Exclusion Plot, 74 Number of non-excluded plots, 81 Velocity / acceleration estimation section (velocity acceleration estimation section), 81H Speed ​​estimation section, 82, 82H aircraft position prediction unit (mobile object position prediction unit), 83, 83F, 83G second aircraft position candidate extraction unit (second mobile body position candidate extraction unit), 84 2nd aircraft position calculation section, 85, 85H Aircraft Position Integration Department, 86, 86H Calculation control section, 87 Plot exclusion section (moving object position exclusion section), 90 plots, 91 aircraft location (average across all plots); 92 locus, 93 Line extending the trajectory, 94 aircraft positions (average of aircraft position candidates) 95 inclusive circle, 96 Aircraft position (center of inclusive circle), 97 predicted aircraft position; 98 trajectory (updated), 99 aircraft position (average of second aircraft position candidates), 100 1st aircraft position, 101 2nd aircraft position, 102 aircraft position (on the line connecting the first aircraft position and the second aircraft position); 103 Excluded Circle.

Claims

1. a position data storage unit that stores the positions of a plurality of receiving stations that receive signals transmitted by a mobile unit; a reception time acquisition unit that acquires a reception time, which is the time when the receiving station received the signal; a receiving station combination generation unit that generates a number of receiving station combinations, which are combinations of the minimum number of receiving stations that have received the signal for positioning, that is, three when the moving object is on the Earth's surface and four when the moving object is in the air, the number of combinations being either a predetermined number or the number of all possible combinations, whichever is smaller; an individual calculated position calculation unit that calculates, for each of the receiving station combinations, an individual calculated position that is a position from which the moving body transmitted the signal, at which each of the receiving stations included in the receiving station combination receives the signal at the reception time, based on the positions of each of the receiving stations included in the receiving station combination and the reception time; a mobile body location candidate extraction unit that extracts mobile body location candidates that are individual calculation positions that satisfy a predetermined neighboring distance condition determined using an adjacent distance set of the individual calculation positions, which is a set of a predetermined first number of the adjacent distances that are consecutively arranged, including the smallest, in a sequence of the adjacent distances that are arranged in ascending order for each of the individual calculation positions, based on an adjacent distance that is a distance between each of the individual calculation positions and another individual calculation position, or that satisfy a predetermined neighboring set condition determined using an adjacent individual calculation position set of the individual calculation position, which is a set of the individual calculation positions that have any of the adjacent distances included in the adjacent distance set; A mobile object monitoring device comprising a mobile object position calculation unit that calculates a mobile object position that is the position of the mobile object based on the mobile object position candidate.

2. 2. The mobile object monitoring device according to claim 1, wherein the mobile object position candidate extraction unit extracts the individual calculated positions whose adjacent distance index determined based on the adjacent distance set satisfies the adjacent distance condition as the mobile object position candidate.

3. 3. The mobile object monitoring device according to claim 2, wherein the mobile object position candidate extraction unit extracts the individually calculated positions for which the adjacent distance index is equal to or less than a predetermined index upper limit value as the mobile object position candidates.

4. 3. The mobile object monitoring device according to claim 2, wherein the mobile object position candidate extraction unit extracts as the mobile object position candidate an individual calculated position whose to-reference ratio, which is a value obtained by dividing the adjacent distance index of the individual calculated position by a reference adjacent distance index which is the sum of the products of the adjacent distance index of each of the individual calculated positions and a second weighting coefficient which is determined based on the number of the individual calculated positions included in the individual calculated position set, the number of the individual calculated positions being consecutively arranged, including the smallest, in the sequence of the individual calculated positions sorted in ascending order of the adjacent distance index, is equal to or less than a predetermined ratio upper limit value.

5. 3. The mobile object monitoring device according to claim 2, wherein the mobile object position candidate extraction unit extracts, as the mobile object position candidate, the individual calculated location for which the adjacent distance index is equal to or less than a predetermined index upper limit value, and the individual calculated location for which a to-reference ratio, which is a value obtained by dividing the adjacent distance index of the individual calculated location by a reference adjacent distance index, which is the sum of the products of a second weighting coefficient determined based on the number of the individual calculated locations in the individual calculated location set, and the adjacent distance index of each of the individual calculated locations, and the adjacent distance index of each of the individual calculated locations, is equal to or less than a predetermined ratio upper limit value.

6. 3. The mobile object monitoring device according to claim 2, wherein the mobile object position candidate extraction unit extracts, as the mobile object position candidate, an individual calculated position whose adjacent distance index is equal to or less than a predetermined index upper limit value and whose to-reference ratio, which is a value obtained by dividing the adjacent distance index of the individual calculated position by a reference adjacent distance index which is the sum of the products of the adjacent distance index of each individual calculated position and a second weighting coefficient which is determined based on the number of individual calculated positions from the smallest in the individual calculated position set, the individual calculated position being a predetermined second number of individual calculated positions arranged consecutively including the smallest in the sequence of the individual calculated positions arranged in ascending order of the adjacent distance index, is equal to or less than a predetermined ratio upper limit value.

7. A mobile object monitoring device as described in any one of claims 2 to 6, wherein the mobile object position candidate extraction unit determines the adjacent distance index of the individual calculated position to be the sum of the products of each adjacent distance and a first weighting coefficient determined based on the number of adjacent distances included in the adjacent distance set of the individual calculated position from the smallest in the adjacent distance set.

8. 7. The mobile object monitoring device according to claim 2, wherein the mobile object position candidate extraction unit determines, as the adjacent distance index of the individual calculation location, the sum of products of a first weighting coefficient determined based on the smallest order of each adjacent distance included in the adjacent distance set of the individual calculation location, and the ranking distance corresponding to each adjacent distance, based on a ranking distance corresponding to the adjacent distance with the counterpart individual calculation location, the ranking distance indicating the smallest order of the adjacent distance with the counterpart individual calculation location in the adjacent distance set of the other individual calculation location, the other individual calculation location having the adjacent distance included in the adjacent distance set of the subject individual calculation location.

9. the mobile object position candidate extraction unit determines that the own individual calculated position and the other individual calculated position belong to the same group when the own individual calculated position is included in the adjacent individual calculated position set of the other individual calculated position that is the individual calculated position, and 2. The mobile object monitoring device according to claim 1, wherein the mobile object position candidate extraction unit extracts, as the mobile object position candidate, the individual calculated position that satisfies the adjacent set condition that the individual calculated position belongs to the group having the largest number of the individual calculated positions belonging to the group.

10. 10. The mobile object monitoring device according to claim 1, wherein the mobile object position calculation unit calculates an average position of the mobile object position candidates as the mobile object position.

11. 10. The mobile object monitoring device according to claim 1, wherein the mobile object position calculation unit calculates the center of the smallest circle that encompasses all of the mobile object position candidates as the mobile object position when the mobile object is on the Earth's surface, and calculates the center of the smallest sphere that encompasses all of the mobile object position candidates as the mobile object position when the mobile object is in the air.

12. a mobile object position history storage unit that stores past positions of the mobile object over a predetermined period of time; 10. The mobile object monitoring device according to claim 1, further comprising: a mobile object trajectory generating unit that generates a mobile object trajectory connecting the mobile object positions stored in the mobile object position history storage unit.

13. a mobile object position history storage unit that stores past positions of the mobile object over a predetermined period of time; a mobile object position prediction unit that calculates a predicted mobile object position, which is a position of the mobile object predicted based on past mobile object positions stored in the mobile object position history storage unit; A mobile object monitoring device as described in any one of claims 1 to 6 and claim 9, further comprising a mobile object position exclusion unit that excludes the individually calculated positions whose distance from the predicted mobile object position is greater than a predetermined first distance from the mobile object position as the mobile object position candidate.

14. a mobile object position history storage unit that stores past positions of the mobile object over a predetermined period of time; a mobile object position prediction unit that calculates a predicted mobile object position, which is a position of the mobile object predicted based on past mobile object positions stored in the mobile object position history storage unit; a speed estimation unit that estimates a speed of the moving object based on past positions of the moving object stored in the moving object position history storage unit; a second moving object position candidate extraction unit that extracts a second moving object position candidate, which is the individually calculated position, such that a prediction difference distance, which is a distance between the individually calculated position and the predicted moving object position, satisfies a predetermined prediction difference distance condition; When the absolute value of the speed is greater than a first speed threshold, the moving object position calculation unit calculates the moving object position based on the moving object position candidate; 2. The mobile object monitoring device according to claim 1, wherein when the absolute value of the speed is smaller than a second speed threshold set to be equal to or less than the first speed threshold, the mobile object position calculation unit calculates the mobile object position based on the second mobile object position candidate.

15. 15. The mobile object monitoring device of claim 14, wherein when the absolute value of the speed is equal to or less than the first speed threshold and equal to or greater than the second speed threshold that is set smaller than the first speed threshold, the mobile object position calculation unit calculates the mobile object position based on the mobile object position candidate and the second mobile object position candidate.

16. When the absolute value of the speed is equal to or less than the first speed threshold and equal to or greater than the second speed threshold that is set smaller than the first speed threshold, the moving body position calculation unit calculates the moving body position on a line segment connecting a first moving body position that is the moving body position calculated by the moving body position calculation unit based on the moving body position candidate and a second moving body position that is the moving body position calculated by the moving body position calculation unit based on the second moving body position candidate, The mobile object monitoring device according to claim 14 , wherein the closer the absolute value of the speed is to the first speed threshold value, the less distant the mobile object position is from the first mobile object position.

17. a mobile object position history storage unit that stores past positions of the mobile object over a predetermined period of time; a mobile object position prediction unit that calculates a predicted mobile object position, which is a position of the mobile object predicted based on past mobile object positions stored in the mobile object position history storage unit; a speed estimation unit that estimates a speed of the moving object based on past positions of the moving object stored in the moving object position history storage unit; a speed and acceleration estimation unit that estimates the speed and acceleration of the moving object based on past positions of the moving object stored in the moving object position history storage unit; a second moving object position candidate extraction unit that extracts a second moving object position candidate, which is the individually calculated position, such that a prediction difference distance, which is a distance between the individually calculated position and the predicted moving object position, satisfies a predetermined prediction difference distance condition; When the absolute value of the velocity is greater than a first velocity threshold value, or when the absolute value of the acceleration is greater than a first acceleration threshold value, the moving object position calculation unit calculates the moving object position based on the moving object position candidate, 2. The mobile object monitoring device of claim 1, wherein the mobile object position calculation unit calculates the mobile object position based on the second mobile object position candidate when the absolute value of the velocity is smaller than a second velocity threshold set to be equal to or smaller than the first velocity threshold and when the absolute value of the acceleration is smaller than a second acceleration threshold set to be equal to or smaller than the first acceleration threshold.

18. 18. The mobile object monitoring device of claim 17, wherein the mobile object position calculation unit calculates the mobile object position based on the mobile object position candidate and the second mobile object position candidate when the absolute value of the velocity is equal to or less than the first velocity threshold and the absolute value of the acceleration is equal to or less than the first acceleration threshold and the absolute value of the velocity is equal to or greater than the second velocity threshold that is set to be smaller than the first velocity threshold, or when the absolute value of the acceleration is equal to or greater than the second acceleration threshold that is set to be smaller than the first acceleration threshold.

19. When the absolute value of the velocity is equal to or less than the first velocity threshold and the absolute value of the acceleration is equal to or less than the first acceleration threshold and the absolute value of the velocity is equal to or greater than the second velocity threshold which is set to be smaller than the first velocity threshold, or when the absolute value of the acceleration is equal to or greater than the second acceleration threshold which is set to be smaller than the first acceleration threshold, the moving body position calculation unit calculates the moving body position on a line segment connecting a first moving body position which is the moving body position calculated by the moving body position calculation unit based on the moving body position candidate and a second moving body position which is the moving body position calculated by the moving body position calculation unit based on the second moving body position candidate, If the absolute value of the velocity is the same, the closer the absolute value of the acceleration is to the first acceleration threshold, the closer the moving object position is to the first moving object position, and 18. The mobile object monitoring device according to claim 17, wherein, if the absolute value of the acceleration is the same, the closer the absolute value of the velocity is to the first velocity threshold value, the less far the mobile object position is from the first mobile object position.

20. 20. The mobile object monitoring device according to claim 14, wherein the second mobile object position candidate extraction unit extracts, as the second mobile object position candidate, the individually calculated position that satisfies the prediction difference distance condition that the prediction difference distance is equal to or less than a value obtained by multiplying the smallest value among the prediction difference distances of all the individually calculated positions by a predetermined coefficient.

21. 20. The mobile object monitoring device according to claim 14, wherein the second mobile object position candidate extraction unit extracts, as the second mobile object position candidate, the individually calculated position that satisfies the prediction difference distance condition, that is, the prediction difference distance is the smallest value among the prediction difference distances of all the individually calculated positions, or the prediction difference distance is equal to or less than a predetermined prediction difference distance upper limit value and equal to or less than a value obtained by multiplying the smallest value by a predetermined coefficient.

22. A mobile object monitoring device as described in any one of claims 14 to 19, further comprising a mobile object position exclusion unit that excludes an individually calculated position whose distance from the predicted mobile object position is greater than a predetermined first distance from the mobile object position as a mobile object position candidate.

23. 20. The mobile object monitoring device according to claim 14, wherein when the mobile object position calculation unit calculates the mobile object position based on the mobile object position candidates, the mobile object position calculation unit calculates an average position of the mobile object position candidates as the mobile object position.

24. 20. A mobile object monitoring device as claimed in any one of claims 14 to 19, wherein when the mobile object position calculation unit calculates the mobile object position based on the mobile object position candidates, if the mobile object is on the Earth's surface, the center of the smallest circle that encompasses all of the mobile object position candidates is calculated as the mobile object position, and if the mobile object is in the air, the center of the smallest sphere that encompasses all of the mobile object position candidates is calculated as the mobile object position.

25. A mobile object monitoring device according to any one of claims 14 to 19, wherein when the mobile object position calculation unit calculates the mobile object position based on the second mobile object position candidate, the average position of the second mobile object position candidate is used as the mobile object position.

26. A mobile object monitoring device as described in any one of claims 14 to 19, wherein when the mobile object position calculation unit calculates the mobile object position based on the second mobile object position candidate, if the mobile object is on the Earth's surface, the center of the smallest circle that encompasses all of the second mobile object position candidate is calculated as the mobile object position, and if the mobile object is in the air, the center of the smallest sphere that encompasses all of the second mobile object position candidate is calculated as the mobile object position.

27. 20. The mobile object monitoring device according to claim 14, further comprising: a mobile object trajectory generating unit that generates a mobile object trajectory connecting the mobile object positions stored in the mobile object position history storage unit.

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