JP7433103B2 - Passing route determination method - Google Patents

Description

The present invention relates to a route determination method for determining a route of a moving object.

In order to monitor the passage of a large number of moving objects such as aircraft, it may be necessary to determine which of a plurality of routes each moving object has passed. For example, in order to monitor the takeoff and landing of an airfield where many aircraft take off and land, it is required to determine which of a plurality of runways each aircraft took off and landed on. Therefore, various route determination techniques exist for such determination.

As an example of a route determination technique, radio waves for measuring ground altitude (in six directions) from an aircraft or radio waves for measuring ground altitude and A measurement device is installed to measure transponder response signal radio waves, and the radio waves for measuring altitude above ground are measured at multiple measurement points corresponding to multiple runways, or radio waves for measuring altitude above ground and transponder response signal radio waves. Based on this, there is a technology that automatically determines which of a plurality of runways an aircraft took off and landed on. (For example, see Patent Document 1, especially FIG. 9 thereof.)

International Publication No. 2002/052526

However, when installing measurement equipment to measure radio waves for each runway, as in the above-mentioned example of the route determination technology, as the number of runways increases, the number of measurement equipment must be increased. , Furthermore, more land must be secured to install the measuring equipment. In this case, as the number of runways increases, the installation work of the measuring equipment becomes complicated and the installation cost of the measuring equipment increases. Furthermore, maintenance of many measuring instruments is complicated, and managing measurement data obtained at many measuring points is complicated. Therefore, for example, there is room for improvement in determining the passage of a moving object such as an aircraft, from the viewpoint of installation of measurement equipment, maintenance, management of measurement data, etc.

Furthermore, military aircraft often do not transmit radio waves to measure altitude over the ground. Therefore, when receiving the above-mentioned example of the passing route determination technique by interception, there is a possibility that sufficient information necessary for determining the passing route of the military aircraft may not be obtained, and the passing route of the military aircraft may not be determined.

In view of these circumstances, it is desirable that the passing route determination method be able to make the passing route determination of moving objects such as aircraft more efficient, and to be able to increase the types of moving objects for which passing routes can be determined. .

In order to solve the above problems, a passing route determination method according to one embodiment includes a step of receiving radio waves of a transponder response signal transmitted from a moving object at first and second measurement points, and a step of receiving radio waves of the transponder response signal transmitted from a moving body. a step of calculating the difference between the reception times at which the above is received at the first and second measurement points, a reference distance predetermined between the first and second measurement points, and a calculated value of the difference between the reception times. a projection point set on a projection straight line passing through the first and second measurement points and a determination distance between the first measurement point based on the calculation of the determination distance according to the passage of time; and determining, based on a change in the calculated value, one of the plurality of routes that the mobile object has passed, and the plurality of routes are located so as to intersect the projected straight line in a plan view. , when the reference distance is p, the calculated value of the difference in reception time is Δt, the speed of the radio wave is c, and the calculated value of the judgment distance is r, the calculated value of the judgment distance is It is obtained by the following (Equation 1).

r = (p-Δt×c)/2... (Formula 1)

In the passing route determination method according to one embodiment, it is possible to make the passing route determination of a moving object such as an aircraft more efficient, and it is possible to increase the types of moving bodies whose passing routes can be determined.

FIG. 1 is a plan view schematically showing two routes to be determined and first and second measurement points used in the determination, in order to explain a route determination method according to an embodiment. FIG. 2 is a flowchart for explaining a route determination method according to an embodiment. FIG. 3 is a configuration diagram of a passage route determination system according to an embodiment. FIG. 4 is a plan view schematically showing two routes to be determined and first and second measurement points used in the determination, in order to explain a route determination method according to a first modification of an embodiment. It is. FIG. 5 is a plan view schematically showing two routes to be determined and first and second measurement points used in the determination, in order to explain a passing route determination method according to a second modification of the embodiment. It is. FIG. 6 is a graph showing the relationship between the elapsed time and the determined distance when the aircraft lands on the first runway from one direction of movement of the first route in the first embodiment. FIG. 7 is a graph showing the relationship between the elapsed time and the determined distance when the aircraft lands on the second runway from one side of the second route in the second embodiment. FIG. 8 is a graph showing the relationship between the elapsed time and the determined distance in the case where the aircraft takes off from the first runway toward one direction of movement of the first route in the third embodiment. FIG. 9 is a graph showing the relationship between the elapsed time and the determined distance in the case where the aircraft takes off from the second runway toward one direction of travel of the second route in the fourth embodiment. FIG. 10 is a graph showing the relationship between the elapsed time and the determined distance when the aircraft lands on the first runway from the second movement direction of the first route in Example 5. FIG. 11 is a graph showing the relationship between the elapsed time and the determined distance when the aircraft lands on the second runway from the other side of the second route in the sixth embodiment. FIG. 12 is a graph showing the relationship between the elapsed time and the determined distance in the case where the aircraft takes off from the first runway toward the other direction of travel of the first route in Example 7. FIG. 13 is a graph showing the relationship between the elapsed time and the determined distance when the aircraft takes off from the second runway toward the other direction of movement of the second route in Example 8.

A route determination method according to an embodiment will be described below. The route determination method according to this embodiment is for determining the route of a moving object. Further, below, a passage route determination system configured to be able to implement the passage route determination method according to the present embodiment will also be described.

Note that, in the present invention, a moving object to be determined is a moving object that can transmit radio waves of a transponder response signal. In this embodiment, the moving object is an aircraft, for example. The aircraft can be an airplane, helicopter, Osprey, Cessna, airship, drone, etc. Furthermore, the moving object may be something other than an aircraft. For example, the moving object can be a vehicle such as a car, a ship, or the like.

"Outline of route determination method"
With reference to FIGS. 1 and 2, an outline of the route determination method according to the present embodiment will be described. That is, the route determination method is roughly as follows. As shown in FIG. 1, in the transit route determination method (hereinafter simply referred to as the "determination method" as needed), an aircraft 1 that transmits radio waves 2 of transponder response signals selects one of a plurality of routes 3. It is determined whether route 3 has been passed. Note that, hereinafter, the route 3 that the aircraft 1 has passed will be referred to as a transit route 3 as necessary.

In FIG. 1, the number of routes 3 to be determined is two. Each route 3 may include a runway 4. However, in the present invention, the number of routes to be determined may be three or more. Furthermore, at least one of the plurality of routes may not include a runway.

Referring to FIGS. 1 and 2, in such a determination method, radio waves 2 of a transponder response signal transmitted from the aircraft 1 are received at the first measurement point 5 and the second measurement point 6 (reception step S1). The difference in reception time when the radio wave 2 of the transponder response signal is received at the first and second measurement points 5 and 6 is calculated (time difference calculation step S2). On the projection straight line 7 passing through the first and second measurement points 5 and 6 based on the reference distance p predetermined between the first and second measurement points 5 and 6 and the calculated value Δt of the difference in reception time. The determination distance between the projection point 8 set in and the first measurement point 5 is calculated (determination distance calculation step S3). Based on the change in the calculated value r of the determination distance over time, one route 3 that the mobile object has passed among the plurality of routes 3 is determined (route determination step S4).

Moreover, as shown in FIG. 1, the plurality of routes 3 are located so as to intersect the projection straight line 7 in a plan view. The projected straight line 7 intersects at least one of the runways 4 in the plurality of routes 3 . The first and second measurement points 5 and 6, the projection straight line 7, the projection point 8, the reference distance p, and the determination distance can be determined on a three-dimensional space. However, the first and second measurement points, the projected straight line, the projected point, the reference distance, and the determination distance can also be determined on a two-dimensional plane.

Furthermore, in the determination method, the calculated value r of the determination distance is defined as the following (Formula 1) based on the relationship between the reference distance p, the calculated value Δt of the difference in reception time, and the radio wave speed c.

r = (p-Δt×c)/2... (Formula 1)

"Travel route determination system"
Here, the route determination system 10 will be explained with reference to FIGS. 1 and 3. A passage route determination system (hereinafter simply referred to as "determination system" as necessary) 10 includes a first measurement device 11 and a second measurement device configured to be able to receive radio waves 2 of transponder response signals transmitted from an aircraft 1. It has a device 12. The first measurement device 11 is installed at the first measurement point 5. The second measurement device 12 is set at the second measurement point 6.

The determination system 10 includes a calculation device 13 that can perform various calculations for determining the passage route 3. The arithmetic unit 13 includes arithmetic processing parts such as a CPU (Central Processing Unit), control parts, storage parts such as a RAM (Random Access Memory) and an HDD (Hard Disc Drive), wireless or wired input parts, and output parts. and/or components such as input/output components. Such arithmetic device 13 is arranged apart from the first and second measuring devices 11 and 12, particularly from the first and second measuring points 5 and 6. However, the computing device can also be integrated with the first or second measuring device.

Each of the first and second measurement devices 11 and 12 has receiving antennas 11a and 12a configured to be able to receive radio waves 2. Each of the first and second measurement devices 11, 12 has a time identification unit 11b, 12b configured to be able to identify the reception time when the radio wave 2 was received by the reception antenna 11a, 12a. Each of the first and second measurement devices 11, 12 has an output unit 11c, 12c configured to output the reception time identified by the time identification unit 11b, 12b to the arithmetic device 13.

The arithmetic device 13 has an input unit 13a configured to receive the reception times output from the output units 11c, 12c of the first and second measurement devices 11, 12. The input unit 13a is electrically connected to the output units 11c and 12c of the first and second measuring devices 11 and 12 by wire or wirelessly. By the output units 11c, 12c and the input unit 13a of the first and second measuring devices 11, 12, the arithmetic device 13 can The identification value of the obtained reception time can be received.

The arithmetic device 13 includes an arithmetic processing unit 13b that can perform various arithmetic operations. The arithmetic processing unit 13b can be an arithmetic processing component such as the CPU described above. The arithmetic device 13 has a display unit 13c configured to be able to display arithmetic results. The display unit 13c is a display configured as the above output component. However, the display unit can also be a printer or the like.

The arithmetic processing unit 13b of the arithmetic device 13 is configured to be able to calculate the difference between the reception time identification values obtained by the time identification units 11b and 12b of the first and second measurement devices 11 and 12. The arithmetic processing unit 13b is also configured to be able to calculate such a difference in reception time.

The arithmetic processing unit 13b calculates a projection point 8 set on a projection straight line 7 passing through the first and second measurement points 5 and 6, and a projection point 8 set on a projection straight line 7 passing through the first and second measurement points 5 and 6, based on the reference distance p and the calculated value Δt of the difference in reception time. It is configured to be able to calculate the determination distance between one measurement point 5 and the other. The arithmetic processing unit 13b can be configured to be able to determine one route 3 that the aircraft 1 has passed among the plurality of routes 3 based on changes in the calculated value r of the determination distance over time. At this time, the display unit 13c can display changes in the calculated value r of the determination distance over time. However, the operator can also determine the passing route based on the display on the display unit instead of the arithmetic processing unit.

"Details of the transit route determination method"
Referring to FIGS. 1, 4, and 5, the passing route determination method can be performed in detail as follows. As shown in FIG. 1, the plurality of routes 3 are spaced apart from each other on the projection straight line 7 in plan view. The plurality of runways 4 intersect the projection straight line 7 at a plurality of intersection points 9, respectively. The plurality of intersection angles respectively set between the plurality of routes 3 and the projection straight line 7 are approximately equal. However, at least one of the plurality of intersection angles can be different from the remainder of the plurality of intersection angles. Each of the plurality of intersection angles can be set to be acute, right, or obtuse.

A plurality of runways 4 can be installed within the premises of the same airport. The plurality of runways 4 are substantially parallel to each other. However, at least one of the plurality of runways can also be inclined with respect to the rest of the plurality of runways.

All of the plurality of paths 3 are arranged between the first and second measurement points 5 and 6. However, in addition to FIG. 1 showing an example of this embodiment, as shown in FIG. 4 showing an example of a first modification of this embodiment, at least one route 3 among the plurality of routes 3 is It can be placed between the first and second measurement points 5, 6. As shown in FIG. 5, which shows an example of the second modification of the present embodiment, the first and second measurement points 5 and 6 are located at both longitudinal ends of the plurality of paths 3 along the projection straight line 7. It can also be arranged between two paths 3, each located at .

As shown in FIG. 1, all of the plurality of runways 4 are arranged between the first and second measurement points 5, 6. However, in addition to FIG. 1 showing an example of this embodiment, as shown in FIG. 4 showing an example of a first modification of this embodiment, at least one runway 4 among the plurality of runways 4 is , between the first and second measurement points 5, 6. As shown in FIG. 5, which shows an example of the second modification of the present embodiment, the first and second measurement points 5 and 6 are set in the longitudinal direction along the projected straight line 7 of the plurality of runways 4. It can also be placed between two runways 4 located at both ends. Further, although not specifically shown in the drawings, a runway may not be disposed between the first and second measurement points.

The aircraft 1 moves along one transit route 3 among the plurality of routes 3 from one direction of movement (indicated by the one-sided arrow F) or from the other direction of movement (indicated by the one-sided arrow D) opposite to the one-sided movement direction. ), it is possible to land on the runway 4 of this one transit route 3. The aircraft 1 takes off from the runway 4 of this one passage route 3 along one passage route 3 of the plurality of routes 3 towards one side movement direction or towards the other side movement direction. I can do it.

Moreover, the above (Formula 1) used in the determination method is derived as follows. First, the determination distance r between the first measurement point 5 and the projection point 8 can be defined by the following (Equation 2) in relation to the identification value t of the first reception time and the radio wave speed c. Note that the first reception time is the time it takes from when the radio wave 2 is transmitted by the aircraft 1 until it is measured at the first measurement point 5.

r = t×c... (Formula 2)

The calculated value q of the sub-determination distance between the second measurement point 6 and the projection point 8 can be defined by the following (Equation 3) in relation to the identification value t2 of the second reception time and the radio wave speed c. Note that the second reception time is the time it takes from when the radio wave 2 is transmitted by the aircraft 1 until it is measured at the second measurement point 6.

q = u×c... (Formula 3)

The identification value u of the second reception time can be defined by the following (Equation 4) based on the relationship between the identification value t of the first reception time and the calculated value Δt of the difference in reception time. Therefore, the calculated value q of the sub-determination distance can be defined by the following (Equation 5).

u = t+Δt... (Formula 4)

q = (t+Δt)×c... (Formula 5)

Therefore, when the calculated value Δt of the difference in reception time is approximately 0 (zero) seconds, the calculated value of the judgment distance p is approximately equal to the calculated value q of the sub-judgment distance, and in this case, the projection point 8 is located on the projection straight line. 7, approximately at the center between the first and second measurement points 5 and 6. When the calculated value Δt of the reception time difference is a positive value, the calculated value p of the judgment distance is smaller than the calculated value q of the sub-judgment distance, and in this case, the projection point 8 is the first point on the projection straight line 7. It will be located closer to measurement point 5. When the calculated value Δt of the reception time difference is a negative value, the calculated value p of the judgment distance is larger than the calculated value q of the sub-judgment distance, and in this case, the projection point 8 is the second It will be located closer to measurement point 6.

The reference distance p between the first and second measurement points 5 and 6 can be defined by the following (Equation 5) in relation to the calculated value r of the determination distance and the calculated value q of the sub-determination distance.

p=r+q... (Formula 6)

Based on the above (Formula 2), (Formula 5), and (Formula 6), the reference distance p can be defined by the following (Formula 7).

p = t×c+((t+Δt)×c)
= (2×t+Δt)×c... (Formula 7)

In this case, the identification value t of the first reception time can be defined as shown in (Equation 8) below.

t = (p/c-Δt)/2... (Formula 8)

If the identification value t of the first reception time in (Formula 8) is substituted into the above (Formula 2), (Formula 1) will be obtained.

r = (p/c-Δt)/2×c
= (p-Δt×c)/2... (Formula 1)

Furthermore, in the reception step S1 of the determination method, the radio wave 2 of the transponder response signal can be intercepted at the first measurement point 5 and/or the second measurement point 6. Furthermore, in the route determination step S4 of the determination method, the route 3 can be determined based on the following determination criteria. A plurality of mutually different intersection distances h are set between the first measurement point 5 and the plurality of intersections 9.

In the route determination step S4, it is determined which of the plurality of intersection distances h the calculated value r of the judgment distance is changing in relation to, as time passes, and thereby It can be determined that the route 3 passing through the intersection 9 related to the intersection distance h determined from the above is the passing route 3. For example, it is determined which of a plurality of intersection distances h the calculated value r of the determination distance changes to straddle, and thereby a route passing through the intersection 9 according to the intersection distance h determined from the plurality of intersection distances h is determined. 3 can be determined to be the passage route 3. In particular, it is preferable that the determination be performed at a portion where the calculated value r of the determination distance changes the most over the entire time period. For example, it is determined which of the plurality of intersection distances h the peak of the calculated value r of the determination distance is approximately equal to or closest to, and thereby the intersection 9 related to the intersection distance h determined from the plurality of intersection distances h is determined. It can be determined that the route 3 to be taken is the route 3 to be passed.

Further, in the route determination step S4, the aircraft 1 can land from one side of the movement direction, land from the other side of the movement direction, or move in the one side movement direction on one of the paths determined for the aircraft 1 to pass. It is possible to determine whether the aircraft took off or took off in the direction of movement on the other side. For example, such a determination can be made based on the rate of change in the calculated value r of the determination distance over time. For example, the determination can be made based on an increase or decrease in the calculated value r of the determination distance over time.

In the route determination step S4, a calculation parameter related to a change in the calculated value r of the determined distance over time is set to a change in the determined distance over time, which is set in advance to correspond to a plurality of routes 3. It is also possible to collate with such collation parameters and further determine that the route 3 associated with the collation parameter with the highest matching rate is the passing route.

As described above, the passage route determination method according to the present embodiment includes the receiving step S1 of receiving the radio wave 2 of the transponder response signal transmitted from the mobile object (aircraft) 1 at the first and second measurement points 5 and 6; a time difference calculation step S2 of calculating the difference in reception time when the radio wave 2 of the transponder response signal is received at the first and second measurement points 5 and 6, and between the first and second measurement points 5 and 6; A projection point 8 set on a projection straight line 7 passing through the first and second measurement points 5 and 6 based on a predetermined reference distance p and the calculated value Δt of the difference in reception time, and the first A judgment distance calculation step S3 of calculating a judgment distance between measurement points 5, and a change in the calculated value r of the judgment distance according to the passage of time, based on which of the plurality of routes 3 the mobile object 1 has passed. a route determination step S4 of determining one route 3, wherein the plurality of routes 3 are located so as to intersect the projection straight line 7 in a plan view, the reference distance is p, and the difference in the reception time is When the calculated value is Δt, the speed of the radio wave 2 is c, and the calculated value of the determination distance is r, the calculated value of the determination distance is obtained by the following (Equation 1).

r = (p-Δt×c)/2... (Formula 1)

In such a determination method, the route 3 of the mobile object (aircraft) 1 can be determined using the first and second measurement points 5 and 6, that is, the two measurement points 5 and 6. In particular, even if the number of routes 3 to be determined increases, the route 3 of the mobile object 1 can be determined using the two measurement points 5 and 6. Therefore, even if the number of routes 3 increases, it is possible to prevent the number of installation steps for the first and second measuring devices 11 and 12 from increasing, and the installation cost for the first and second measuring devices 11 and 12 can be prevented from increasing. Furthermore, maintenance of the first and second measuring devices 11 and 12 can be facilitated, and management of measurement data can be facilitated. Therefore, it is possible to make the determination of the passage route of the mobile object 1 more efficient. Furthermore, if the moving object 1 emits the radio wave 2 of the transponder response signal, its passing route 3 can be determined, so even if the moving object 1 is a military aircraft, for example, its passing route 3 can be determined. Therefore, the types of moving objects 1 whose passage routes 3 can be determined can be increased.

In the transit route determination method according to the present embodiment, the mobile object 1 is an aircraft 1, each of the plurality of routes 3 includes a runway 4, and the projected straight line 7 is a runway on the plurality of routes 3. Intersects at least one of 4. Therefore, it is possible to efficiently determine the runway 4 on which the aircraft 1 takes off and lands. Moreover, the types of aircraft 1 that can determine the runway 4 used for takeoff and landing can be increased.

In the passing route determination method according to the present embodiment, the first and second measurement points 5, 6, the projected straight line 7, the projected point 8, the reference distance p, and the determined distance are arranged in a three-dimensional space. determined. In such a passing route determination method, the passing route 3 of the moving body 1 in the three-dimensional space can be determined based on the position information including the altitude of the moving body 1. Therefore, the three-dimensional passage route determination of the moving body 1 can be made more efficient.

Although the embodiments of the present invention have been described so far, the present invention is not limited to the above-described embodiments, and the present invention can be modified and changed based on the technical idea thereof.

Examples 1 to 8 will be explained. In each of Examples 1 to 8, it is determined whether or not it is possible to determine which of the two routes 3 the aircraft 1 has passed, shown as an example in FIG. I checked. Furthermore, it was confirmed whether it was possible to determine whether the aircraft 1 moved towards one side or the other side of the passage route 3 using the route determination method of the above embodiment. For such confirmation, in Examples 1 to 8, changes in the calculated value r of the determination distance over time were measured. The conditions for Examples 1 to 8 were as follows.

In each of Examples 1 to 8, the two routes 3 shown as an example in FIG. 1 are distinguished by being called a first route and a second route, respectively. When making this distinction, the first route is designated by 3a, and the second route is designated by 3b. Furthermore, the symbol F1 is used for a one-sided arrow indicating the direction of movement on one side of the first route 3a, and the symbol F2 is used for the one-sided arrow indicating the direction of movement on one side of the second route 3b. The symbol D1 is used for a one-sided arrow indicating the other side moving direction of the first route 3a, and the symbol D2 is used for the one-sided arrow indicating the other side moving direction of the second route 3b.

The two runways 4 shown as an example in FIG. 1 are distinguished by being referred to as a first runway and a second runway, respectively. When making this distinction, the reference numeral 4a is used for the first runway, and the reference numeral 4b is used for the second runway. The first runway 4a is included in the first route 3a, and the second runway 4b is included in the second route 3b.

The two intersection points 9 shown as an example in FIG. 1 are distinguished by being called a first intersection point and a second intersection point, respectively. When making this distinction, the first intersection point is designated by 9a, and the second intersection point is designated by 9b. The first intersection 9a is the intersection between the first path 3a and the projection straight line 7, and the second intersection 9b is the intersection between the second path 3b and the projection straight line 7.

The two intersection distances h shown as an example in FIG. 1 are distinguished by respectively calling them a first intersection distance and a second intersection distance. When making this distinction, the code h1 is used for the first intersection distance, and the code h2 is used for the second intersection distance.

In each of Examples 1 to 8, the passage route determination was performed for the aircraft 1 taking off and landing at Osaka International Airport (Itami Airport). Osaka International Airport has two runways called Runway A and Runway B, respectively. In FIG. 1, the first runway 4a corresponds to Runway A, and the first route 3a corresponds to the route of aircraft taking off and landing from Runway A. The second runway 4b corresponds to Runway B, and the second route 3b corresponds to the route of aircraft taking off and landing on Runway B.

The first and second measurement points 5 and 6 were determined so that the first and second runways 4a and 4b were located between the first and second measurement points 5 and 6. First and second measurement devices 11 and 12 were installed at such first and second measurement points 5 and 6, respectively. The projected straight line 7 has a first intersection 9a located closer to the first measurement point 5 in the movement direction on the other side of the first path 3a, and a second intersection 9b located closer to the second measurement point 6 in the second path 3b. It was decided to place it on one side in the direction of movement.

The reference distance p between the first and second measurement points 5 and 6 was approximately 1000 m (meters). The first intersection distance h1 between the first measurement point 5 and the first intersection 9a was approximately 475 m (meters). The second intersection distance h2 between the first measurement point 5 and the second intersection 9b was approximately 820 m.

In Example 1, the aircraft 1 landed on the first runway 4a from one side of the first route 3a. In Example 2, the aircraft 1 landed on the second runway 4b from one direction of movement of the second route 3b. In Example 3, the aircraft 1 took off from the first runway 4a toward one side of the first route 3a. In Example 4, the aircraft 1 took off from the second runway 4b toward one side of the second route 3b.

In Example 5, the aircraft 1 landed on the first runway 4a from the other direction of movement of the first route 3a. In Example 6, the aircraft 1 landed on the second runway 4b from the other direction of movement of the second route 3b. In Example 7, the aircraft 1 took off from the first runway 4a toward the other side of the first route 3a. In Example 8, the aircraft 1 took off from the second runway 4b toward the other side of the second route 3b.

In Examples 1 to 8, measurement results regarding changes in the calculated value r of the determination distance over time were obtained. The measurement results of Examples 1 to 8 are shown in FIGS. 6 to 13, respectively. In each of FIGS. 6 to 13, the vertical axis R indicates the calculated value r of the determination distance, and the unit of the calculated value r of the determination distance is "m (meter)". In each of FIGS. 6 to 13, the horizontal axis T indicates the passage of time, and the unit of time is "s (second)". In FIGS. 6 to 13, the measurement data of Examples 1 to 8 are indicated by solid lines M1 to M8, respectively. In addition, the movement trajectories (indicated by one-sided arrow W) of the aircraft 1 of Examples 1 to 8 are shown in the frame E at the top right of the paper in FIGS. Shown with

As shown in FIG. 6, the measurement results of Example 1 were characterized in that the calculated value r of the determination distance decreased over time. Furthermore, the measurement results of Example 1 were characterized in that the calculated value r of the determination distance rapidly decreased in the middle of the time lapse so as to straddle approximately 475 m, which corresponds to the first intersection distance h1. Due to such characteristics, in Example 1, it was possible to confirm that the aircraft 1 landed on the first runway 4a from one side of the first route 3a.

As shown in FIG. 7, the measurement results of Example 2 show that the calculated value r of the judgment distance changes slightly in the first half of the time lapse, and rapidly increases and reaches the peak in the middle of the time lapse before reaching the peak. It was characterized by a rapid decrease afterwards, and a slight change towards the end of the time course. The measurement results of Example 2 were characterized in that the peak was located near about 820 m, which corresponds to the second intersection distance h2. Due to such characteristics, in Example 2, it was possible to confirm that the aircraft 1 landed on the second runway 4b from one direction of movement of the second route 3b.

As shown in FIG. 8, the measurement results of Example 3 show that the calculated value r of the judgment distance decreases rapidly at the beginning of the lapse of time, changes slightly in the middle of the lapse of time, and rapidly increases at the end of the lapse of time. It had the characteristic of The measurement results of Example 3 were characterized in that the calculated value r of the determination distance was around 475 m, which corresponds to the first intersection distance h1, in the first half of the time elapsed. Due to such characteristics, in Example 3, it was confirmed that the aircraft 1 took off from the first runway 4a toward one side of the first route 3a.

As shown in FIG. 9, the measurement results of Example 4 show that the calculated value r of the judgment distance increases rapidly before reaching the peak in the first half of the time lapse, rapidly decreases after reaching the peak, and decreases rapidly in the middle of the time lapse. It was characterized by a slight change in the temperature and a gradual increase towards the end of the time course. The measurement results of Example 4 were characterized in that the peak was located near about 820 m, which corresponds to the second intersection distance h2. Due to such characteristics, in Example 4, it was confirmed that the aircraft 1 took off from the second runway 4b toward one side of the second route 3b.

As shown in FIG. 10, the measurement results of Example 5 were characterized in that the calculated value r of the determination distance gradually decreased over time. Furthermore, the measurement results of Example 5 were characterized in that the calculated value r of the determination distance was around about 475 m, which corresponds to the first intersection distance h1, from the middle to the latter half of the time lapse. Due to such characteristics, in Example 5, it was possible to confirm that the aircraft 1 landed on the first runway 4a from the other direction of movement of the first route 3a.

As shown in FIG. 11, the measurement results of Example 6 show that the calculated value r of the judgment distance gradually decreases at the beginning of the time lapse, increases gradually in the middle of the time lapse, and increases before reaching the peak in the latter half of the time. It was characterized by a rapid increase and a rapid decrease after reaching a peak. The measurement results of Example 6 were characterized in that the peak was located near about 820 m, which corresponds to the second intersection distance h2. Due to such characteristics, in Example 6, it was possible to confirm that the aircraft 1 landed on the second runway 4b from the other direction of movement of the second route 3b.

As shown in FIG. 12, the measurement results of Example 7 were characterized in that the calculated value r of the determination distance gradually increased over time. Furthermore, the measurement results of Example 7 were characterized in that the calculated value r of the determination distance was around 475 m, which corresponds to the first intersection distance h1, in the first half of the time elapsed. Due to such characteristics, in Example 7, it was confirmed that the aircraft 1 took off from the first runway 4a toward the other side of the first route 3a.

As shown in FIG. 13, the measurement results of Example 8 showed that the calculated value r of the judgment distance changed slightly at the beginning of the time lapse, and then rapidly increased and reached the peak before reaching the peak in the middle of the time lapse. It was characterized by a rapid decrease later on, and a gradual decrease in the latter half of the time. Furthermore, the measurement results of Example 8 were characterized in that the peak was located near about 820 m, which corresponds to the second intersection distance h2. Due to such characteristics, in Example 8, it was confirmed that the aircraft 1 took off from the second runway 4b toward the other side of the second route 3b.

In Examples 1 to 8, it was confirmed that the route of the aircraft 1 could be determined by the route determination method described above. Further, the moving direction of the aircraft 1 on the passing route 3 could be confirmed by the above-mentioned passing route determination method.
In order to maintain the disclosures of the present application as originally filed, the contents of claims 1 to 3 as originally filed are added below.
(Claim 1)
a step of receiving radio waves of a transponder response signal transmitted from the mobile object at first and second measurement points;
Calculating the difference in reception times at which the radio waves of the transponder response signal were received at the first and second measurement points, respectively;
a projection point set on a projection straight line passing through the first and second measurement points based on a predetermined reference distance between the first and second measurement points and a calculated value of the difference in reception time; and calculating a determination distance between the first measurement points;
determining one route that the mobile object has passed among a plurality of routes based on a change in the calculated value of the determination distance over time;
including;
The plurality of routes are located so as to intersect the projected straight line in a plan view,
When the reference distance is p, the calculated value of the difference in reception time is Δt, the speed of the radio wave is c, and the calculated value of the determination distance is r,
The calculated value of the determination distance is
r = (p-Δt×c)/2... (Formula 1)
A transit route determination method obtained by
(Claim 2)
the mobile object is an aircraft,
each of the plurality of routes includes a runway;
The route determination method according to claim 1, wherein the projected straight line intersects at least one of the runways in the plurality of routes.
(Claim 3)
The route determination method according to claim 1, wherein the first and second measurement points, the projected straight line, the projected point, the reference distance, and the determination distance are determined on a three-dimensional space.

1...Aircraft (mobile object), 2...Radio wave, 3...Route, 4...Runway, 5...First measurement point, 6...Second measurement point, 7...Projected straight line, 8...Projected point p...Reference distance, Δt ...Calculated value of reception time difference, c...Radio wave speed, r...Calculated value of judgment distance S1...Reception process, S2...Time difference calculation process, S3...Judgment distance calculation process, S4...Route judgment process

Claims (3)

a step of receiving radio waves of a transponder response signal transmitted from the mobile object at first and second measurement points;
Calculating the difference in reception times at which the radio waves of the transponder response signal were received at the first and second measurement points, respectively;
a projection point set on a projection straight line passing through the first and second measurement points based on a predetermined reference distance between the first and second measurement points and a calculated value of the difference in reception time; and calculating a determination distance between the first measurement points;
Among a plurality of routes that are located to intersect the projected straight line in a plan view, have a plurality of intersection points on the projected straight line, and have a plurality of intersection distances between the plurality of intersection points and the first measurement point, a step of determining a route having an intersection distance equal to or closest to the calculated value of the determined distance with the largest change in the calculated value of the determined distance over the entire passage of time as one route passed by the moving body; including,
When the reference distance is p, the calculated value of the difference in reception time is Δt, the speed of the radio wave is c, and the calculated value of the determination distance is r,
The calculated value of the determination distance is
r = (p-Δt×c)/2... (Formula 1)
A transit route determination method obtained by the mobile object is an aircraft,
each of the plurality of routes includes a runway;
The route determination method according to claim 1, wherein the projected straight line intersects at least one of the runways in the plurality of routes. The route determination method according to claim 1, wherein the first and second measurement points, the projected straight line, the projected point, the reference distance, and the determination distance are determined on a three-dimensional space.