JP4794416B2 - Target location system - Google Patents

Description

  The present invention relates to a target position locating apparatus that determines a target position by analyzing radio waves radiated from a target using a plurality of azimuth measuring apparatuses.

It is known to determine the position of a target by analyzing radio waves radiated from the target using a plurality of azimuth measuring devices and the like.
For example, a position information unit that measures the direction of the target by receiving a radio wave transmitted from the target, a position setting unit that sets the self-position, and a reference direction of the direction of the incoming radio wave for the position information unit In a target position locating device that uses at least two azimuth measuring devices equipped with a reference azimuth setting unit to measure a target position, the other party's own position is measured and the other party's own position is obtained by using the position information unit of each other. The target position is determined with high accuracy by calculating the reference direction that is the reference for obtaining the target direction based on the other party's direction and the other party's own position. The device is known. (See Patent Document 1)
JP-A-6-241817

When locating the target position using the principle of triangulation, etc. by analyzing the radio waves radiated from the target using multiple azimuth measuring devices, measurements were performed from directions close to each other perpendicular to the target. In this case, the target position can be determined with high accuracy. However, when the direction of the target is measured from a direction close to the target, there is a problem that a position determination error is large.
In order to solve this, it is necessary to measure the direction of the target from directions orthogonal to each other as much as possible, but there is a restriction on the flightable area of an aircraft etc. equipped with a direction measuring device, such as the presence of a dangerous area around the target In such a case, measurement cannot always be performed from directions orthogonal to each other.

  An object of the present invention is to enable an aircraft or the like equipped with a direction measuring device to perform measurement from directions that are equivalent to directions orthogonal to each other equivalently when viewed from the target, without entering the danger area around the target. The present invention provides a target position locating device that performs target position locating with high accuracy.

Target position locating system of the present invention, the target of performing the orientation of the target position based on the target azimuth observations from the azimuth measuring device provided at least two moving aircraft, the observation points which are respectively mounted on the ship or vehicle In the location system,
A first target radio wave receiving unit that receives radio waves from the target, a first target azimuth calculating unit that calculates a target azimuth using the target radio wave received by the first target radio wave receiving unit, A first self-position calculation unit that calculates coordinates, a first search result 1 obtained by the first target azimuth calculation unit, and a first position coordinate data obtained by the first self-position calculation unit are transferred. Observation data transfer unit, direction finding result 1 from the first observation data transfer unit and a first recording unit for recording data of the self-position coordinates, and direction finding result from the first observation data transfer unit 1 and a first observation point azimuth measuring device provided with a first communication unit for transmitting the data of the self-position coordinates to a second observation point azimuth measuring device which will be described later. A second target radio wave receiving unit for receiving the reflected radio wave, and the second eye A second target azimuth calculating unit that calculates a target azimuth using the target radio wave received by the radio wave receiving unit, a second self-position calculating unit that calculates the coordinates of the own device position, and the second target azimuth calculating unit 2 and the second observation data transfer unit for transferring the data of the self-position coordinates obtained by the second self-position calculation unit, and the direction search result 2 from the second observation data transfer unit And a second recording unit for recording data of the self-position coordinates, a second communication unit for receiving the direction finding result 1 and the data of the self-position coordinates from the first communication unit, and the position coordinates of the reflecting surface A reflection surface information holding unit that holds in advance information on the angle of the reflection surface, a direction finding result 1 (Θ1) and self-position coordinates (x1, y1) from the second communication unit, and second observation data Direction finding result 2 (Θ2) from the transfer unit, self-position coordinates (x2, y2), and The second observation is provided with a target position locating processing unit that performs calculation processing based on the reflection surface position coordinates (x3, y3) and the reflection surface angle (Θ3) from the reflection surface information holding unit to determine the target position. A point azimuth measuring device, and the angle formed between the target azimuth of the azimuth measuring device at the first observation point and the target azimuth of the azimuth measuring device at the second observation point is more perpendicular than when there is no reflecting surface Measured from the direction close to.

  By using the reflected wave at the reflection surface or reflection point at an appropriate position, the target position can be determined with high precision by equivalently observing from directions close to each other when viewed from the target. It becomes. As a result, it can be expected that the target position can be determined with a predetermined accuracy without causing the aircraft or the like equipped with the measuring apparatus to enter the dangerous flight area or the like, and the fuel of the aircraft can be saved.

Embodiment 1
A target position locating apparatus according to Embodiment 1 of the present invention will be described with reference to FIGS. FIG. 1 is a block diagram of Embodiment 1 of the present invention, FIG. 2 is an explanatory diagram of processing contents showing basic processing when a reflecting surface is not used, and FIG. 3 is a calculation example of a position location result by observation from close directions. FIG. 4 is an explanatory diagram of processing contents when a reflecting surface is used, and FIG. 5 is a diagram showing a calculation example of a position location result by observation from an equivalently spaced direction.

  In the block diagram of FIG. 1, an azimuth measuring device 1 mounted on an aircraft, a ship, a vehicle, or the like or fixed to the ground is located at a first observation point and has a function of searching for an incoming radio wave from a target 3 Have Similarly, the azimuth measuring device 2 mounted on an aircraft, a ship, a vehicle, or the like or fixed on the ground is located at the second observation point, and the incoming radio wave radiated from the target 3 and reflected by the known reflecting surface 4 is used. Has a direction finding function. The reflecting surface 4 may be a reflector mounted on an aircraft, a ship, a vehicle, or the like, or a building on the ground, and the position coordinates and the reflecting surface angle are already known. Furthermore, the observation points of these azimuth measuring apparatuses 1 and 2 do not have to be actually located in directions orthogonal to each other when viewed from the target 3. In the following description, a case where the azimuth measuring apparatuses 1 and 2 are mounted on an aircraft will be described.

  The azimuth measuring apparatus 1 mounted on the aircraft A includes a target radio wave receiving unit 10 that receives radio waves from the target 3, a target azimuth calculating unit 11 that calculates a target azimuth using the target radio waves received by the target radio wave receiving unit 10, The self-position calculation unit 12 that calculates the coordinates of its own position, the direction finding result 1 (Θ1) obtained by the target orientation calculation unit 11 and the data of the self-position coordinates (x1, y1) obtained by the self-position calculation unit 12 are recorded. The observation data transfer unit 13 for transferring to the unit 14 and the communication unit 15, the recording unit 14 for recording the data transferred from the observation data transfer unit 13, and the data transferred from the observation data transfer unit 13 at the second observation point. A communication unit 15 that transmits to the direction measuring device 2 mounted on the aircraft B is provided.

The azimuth measuring apparatus 2 mounted on the aircraft B includes a target radio wave receiving unit 20 that receives a radio wave emitted from the target 3 and reflected by a known reflecting surface 4, and a target azimuth calculation that calculates a target azimuth using the received target radio wave. Unit 21, a self-position calculation unit 22 that calculates the coordinates of the position of the own device, and the direction finding result 1 (Θ1) and the observation data of the self-position coordinates (x1, y1) transmitted from the communication unit 15 of the direction measuring device 1 are received. The communication unit 23, the reflection surface information holding unit 24 that stores in advance information on the position coordinates (x3, y3) of the reflection surface 4 and the angle (Θ3) of the reflection surface 4, and the search result 1 (Θ1) input from the communication unit 23 ), Self-position coordinates (x1, y1), self-position coordinates (x2, y2) input from the self-position calculation section 22, direction finding result 2 (Θ2) input from the target orientation calculation section 21, and reflecting surface information Reflection input from the holding unit 24 Position coordinates (x3, y3) and the target position location processor 25 for determining the orientation results of the target position by using a reflecting surface angle (.THETA.3), the input information to the target position location processor 25 records the user a target position orientation results And a display recording unit 26 having the functions of a display unit and a display unit. The target position locator 25 is a communication unit (not shown) for transmitting information of each input data (x1, y1 to x3, y3, Θ1 to Θ3) to the display recording unit 26 or the ground position locator. It also has a function of an observation data transfer unit for transferring to (omitted).
Note that the above-described self-position calculating units 12 and 22 may automatically measure the self-position using a GPS (Global Positioning System) receiver or may manually set the self-position. Further, since the information on the position coordinates (x3, y3) and the reflection surface angle (Θ3) of the reflection surface 4 held in the reflection surface information holding unit 24 is already known, it is built in the target position determination processing unit 25 as a memory. You may do it.

Next, in Embodiment 1 of the present invention, processing contents for locating the target 3 from the direction finding results (Θ1, Θ2) calculated by the azimuth measuring apparatuses 1 and 2 at the first observation point and the second observation point explain. First, as a preliminary explanation, a case where there is no reflecting surface 4 will be described with reference to FIG.
FIG. 2A shows that the azimuth measuring device 1 located at the first observation point (hereinafter referred to as observation point 1) and the azimuth measurement device 2 located at the second observation point 2 (hereinafter referred to as observation point 2) set the target 3. FIG. 2 (b) shows a direction finding result at observation point 1 and observation point 2 with the direction measurement devices 1 and 2 on the XY plane and the reference direction as the X axis. It is a figure which shows the processing content which calculates | requires a target position from ((theta) 1, (theta) 2).
In FIG. 2, the true target position coordinates are (x, y) = (0, 0). This is unknown. At this time, the position coordinates of the observation point 1 and the observation point 2 are expressed in polar coordinates as follows.
Position coordinates of observation point 1 (x1, y1) = (r1 · cos θ1, r1 · sin θ1)
Position coordinates of observation point 2 (x2, y2) = (r2, cos θ2, r2, cos θ2)
Here, θ1 is an angle formed by a line connecting the observation point 1 and the target 3 with the X axis, and θ2 is an angle formed by a line connecting the observation point 2 and the target 3 with the X axis. r1 is the distance between the observation point 1 and the target 3, and r2 is the distance between the observation point 2 and the target 3.

When the direction finding error at observation point 1 is φ1, the direction finding error at observation point 2 is φ2, and the direction finding result at observation point 1 and observation point 2 is expressed by a straight line expression, it is as follows.
Observation result at observation point 1 y = a1 · x + b1 (1)
a1 = tan (θ1−φ1)
b1 = r1sin θ1-tan (θ1-φ1) · r1cos θ1
= Y1-tan (θ1-φ1) · x1
θ1-φ1 = Θ1 + 180 °
Θ1: Target search result at observation point 1 (Search result 1)
Observation result at observation point 2 y = a2 · x + b2 (2)
a2 = tan (θ2−φ2)
b2 = r2sin θ2-tan (θ2-φ2) · r2cos θ2
= Y2-tan (θ2-φ2) · x2
θ2-φ2 = Θ2 + 180 °
Θ2: Target search result at observation point 2 (Search result 2)

The coordinates of the target position can be obtained by the principle of triangulation by obtaining the intersection of the above equations (1) and (2).
That is, the target position coordinates (target position determination result) are expressed by the following equation (3).
(X, y) = ((b2-b1) / (a1-a2), (a1b2-a2b1) / (a1-a2))
... (3)
Therefore, the communication unit 15 transmits the self-position coordinates (x1, y1) obtained from the self-position calculation unit 12 of the azimuth measuring apparatus 1 at the observation point 1 and the direction finding result 1 (Θ1) obtained from the target azimuth calculation unit 11 to the observation point. 2 and using the self-position coordinates (x2, y2) obtained from the self-position calculation unit 22 of the azimuth measuring device 2 at the observation point 2 and the direction finding result 2 (Θ2) obtained from the target azimuth calculation unit 21 The target position can be determined by the target position determination processing unit 25 of the azimuth measuring apparatus 2 at the observation point 2.

Usually, the target 3 to be located is located in a flight danger area where an aircraft or the like cannot easily fly and enter, so the aircraft A (observation point 1) and the aircraft B (observation point 2) You have to search from a close direction. Therefore, the positioning error is inevitably increased. A calculation example in which the position determination result is simulated will be described with reference to FIG.
As shown in FIG. 3, when the target position is determined by performing the direction finding from the direction close to the target 3, the slope of the straight line of the direction finding result at the two observation points 1 and 2 becomes a close value. The distribution of the intersection of these two straight lines also varies greatly. As a result, when r1 of observation point 1 is 80 [NM (rms)], θ1 is 250 [deg], r2 of observation point 2 is 100 [NM (rms)], and θ2 is 284 [deg], the position is determined. The error is 23.5 [NM (rms)], and the positioning error is large.

Therefore, as shown in FIG. 4, by performing the target position determination using the reflected wave from the reflection surface 4 whose position coordinates and angle are known, the position determination accuracy can be greatly improved. The processing contents of target position determination when the reflecting surface 4 is used will be described. First, the direction finding result 1 (Θ1) and the self-position coordinates (x1, y1) are obtained at the observation point 1 and transmitted to the observation point 2. Next, at the observation point 2, by calculating the azimuth of the reflected wave by the reflecting surface 4, the same result can be obtained as if the direction search was equivalently performed from the straight line connecting the target 3 and the reflecting surface 4.
Equivalent method of finding 2 Θ2 '= 2Θ3-Θ2
Θ2: Direction finding result at observation point 2
Θ3: angle of reflection surface (pre-registered in reflection surface information holding unit 24)

（ｘ３，ｙ３）：反射面の位置座標（反射面情報保持部２４に予め登録）
（ｘ２，ｙ２）：観測点２の位置座標
Θ４＝２（Θ３−Θ２）
以上より反射波を用いて求めた等価的な方探結果２（Θ２’）及び等価的な観測点２の位置座標（ｘ２’，ｙ２’）をそれぞれ方探結果２（Θ２）、観測点２の位置座標（ｘ２，ｙ２）として反射面がない場合と同じ処理により位置標定を行うことによって、目標に対して離隔した方向（目標からみて互いに直交する方向に近い方向）から方探を行ったのと同様な高い精度での目標位置標定が可能となる。この処理は航空機Ｂ（観測点２）の方位測定装置２の目標位置標定処理部２５で実施する。 An equivalent position coordinate of the observation point 2 can be obtained by the following equation (4).

(X3, y3): Position coordinates of the reflecting surface (registered in advance in the reflecting surface information holding unit 24)
(X2, y2): Position coordinates of observation point 2
Θ4 = 2 (Θ3-Θ2)
As described above, the equivalent direction finding result 2 (Θ2 ′) obtained by using the reflected wave and the position coordinates (x2 ′, y2 ′) of the equivalent observation point 2 are obtained as the direction finding result 2 (Θ2) and the observation point 2 respectively. As the position coordinates (x2, y2), the position is determined by the same process as when there is no reflecting surface, and the direction is searched from directions separated from the target (directions close to each other perpendicular to the target). The target position can be determined with high accuracy similar to the above. This processing is performed by the target position locating processing unit 25 of the direction measuring device 2 of the aircraft B (observation point 2).

FIG. 5 shows a calculation example in which the target position locating result is simulated when the direction search is performed from the direction that is equivalently separated from the target by using the reflecting surface 4.
As shown in FIG. 5, by performing a direction search from a direction that is equivalently separated from the target, the inclinations of the direction search results at the two observation points 1 and 2 become nearly vertical. The variation of the distribution at the intersection of the points becomes small, and the target position can be determined with high accuracy. As a result, when r1 at observation point 1 is 80 [NM (rms)], θ1 is 250 [deg], r2 at observation point 2 is 100 [NM (rms)], and θ2 is 350 [deg], the position is determined. The error is 4.6 [NM (rms)], and the positioning error is small.

Embodiment 2
In the first embodiment of the present invention, the apparatus and the processing content for performing the target position determination using the information of the reflecting surface 4 whose position coordinates and angle are known are shown. However, in the first embodiment, the target signal is specularly reflected by the reflecting surface 4. And the angle of the reflecting surface 4 needs to be known. In the second embodiment of the present invention, the reflection point 5 is used instead of the reflection surface 4, and the hyperbolic method is used by using the time difference between the target signals arriving at the observation point 1 and the observation point 2 even if the target signal is not specularly reflected by the reflection surface. The target position can be determined by combining.

  A target position locating device according to Embodiment 2 of the present invention will be described with reference to FIGS. FIG. 6 is a block diagram of Embodiment 2 of the present invention, FIG. 7 is an explanatory diagram of processing contents showing basic processing when a reflection point is not used, and FIG. 8 is a calculation example of a position location result by observation from close directions. FIG. 9 is an explanatory diagram of processing contents when a reflection point is used, and FIG. 10 is a diagram showing a calculation example of a position location result by observation from an equivalently spaced direction.

  In the block configuration diagram of FIG. 6, the same or corresponding parts as those in the block configuration diagram of the first embodiment shown in FIG. Orientation measuring devices 1 and 2 mounted on an aircraft, a ship, a vehicle, etc. (aircraft in FIG. 6) are positioned at the first observation point and the second observation point, respectively. The azimuth measuring device 1 has a function of searching for incoming radio waves from the target 3. The azimuth measuring device 2 has a function of searching for an incoming radio wave emitted from the target 3 and reflected by a known reflection point 5. The reflection point 5 may be a reflector mounted on an aircraft, a ship, a vehicle, or the like, or a building on the ground, and its position coordinates are already known. The observation points of these azimuth measuring apparatuses 1 and 2 do not have to be actually located in directions orthogonal to each other when viewed from the target 3.

  The azimuth measuring apparatus 1 mounted on the aircraft A (observation point 1) includes a target radio wave receiving unit 10 that receives radio waves from a target, a target azimuth calculation unit 11 that calculates a target azimuth using the received target radio waves, The self-position calculating unit 12 that calculates the coordinates of the GPS receiver 16 for synchronizing the time between the aircraft A (observation point 1) and the aircraft B (observation point 2), and the signal from the GPS receiver 16 are received. A signal arrival time measurement unit 17 that measures the signal arrival time using the target radio wave, a direction finding result 1 (Θ1) obtained by the target azimuth calculation unit 11, and a self-position coordinate (x1, y1) obtained by the self-position calculation unit 12 And the observation data transfer unit 13 that transfers the data of the signal arrival time 1 (t1) obtained by the signal arrival time measurement unit 17 to the communication unit 15 and the recording unit 14, and the data transferred from the observation data transfer unit 13 is the aircraft B ( To observation point 2) Communication unit 15 for sending, and a recording unit 14 for recording the data transferred from the observed data transfer unit 13.

The azimuth measuring apparatus 2 mounted on the aircraft B (observation point 2) includes a target radio wave reception unit 20 that receives radio waves emitted from the target and reflected / scattered at the reflection point 5, and a self-position calculation unit that calculates the coordinates of the position of the aircraft. 22, a communication unit 23 that receives observation data of the direction finding result 1 (Θ1), the self-position coordinates (x1, y1), and the signal arrival time (t1) transmitted from the communication unit 15 of the aircraft A (observation point 1); A GPS receiver 27 for synchronizing time between the aircraft A (observation point 1) and the aircraft B (observation point 2), signals from the GPS receiver 27 and the received target radio wave are used to measure the signal arrival time. Signal arrival time measuring unit 28, reflection point information holding unit 29 holding information of position coordinates (x3, y3) of reflection point 5 in advance, direction finding result 1 (Θ1) input from communication unit 23, self-position coordinates (x1) , Y1) and signal arrival time (t1), The self-position coordinates (x2, y2) input from the self-position calculation unit 22, the signal arrival time (t2) input from the signal arrival time measurement unit 28, and the reflection point position coordinates (from the reflection point information holding unit 29) Functions of a recording unit and a display unit that record input information to the target position locating processing unit 25 and the target position locating processing unit 25 that obtain a target position locating result using x3, y3) and display the target position locating result to the user. The display recording unit 26 is provided. The target location processing unit 25 is a communication unit for transmitting information of each input data (x1, y1 to x3, y3, Θ1, t1 to t2) to the display recording unit 26 or the ground location unit. It also has a function of an observation data transfer unit for transferring to (not shown).
Since the information of the position coordinates (x3, y3) of the reflection point 5 held in the reflection point information holding unit 29 is already known, it may be built in the target position locating processing unit 25 as a memory.

Next, in the second embodiment of the present invention, the target is calculated from the difference between the direction finding result (Θ1) calculated by the azimuth measuring device 1 at the first observation point and the signal arrival time calculated by the azimuth measuring device 2 at the second observation point. The content of the process of locating the position 3 will be described. First, as a preliminary explanation, a case where there is no reflection point 5 will be described with reference to FIG.
FIG. 7A shows that the azimuth measuring device 1 located at the first observation point (hereinafter referred to as observation point 1) and the azimuth measurement device 2 located at the second observation point 2 (hereinafter referred to as observation point 2) set the target 3. FIG. 7 (b) shows a direction search result (Θ1) at the observation point 1 with the azimuth measuring devices 1 and 2 on the XY plane and the reference azimuth as the X axis. It is a figure which shows the processing content which calculates | requires a target position from the signal arrival time difference in the observation point.
In FIG. 7, the true target position coordinates are (x, y) = (0, 0). This is unknown. At this time, the position coordinates of the observation point 1 and the observation point 2 are expressed in polar coordinates as follows.
Position coordinates of observation point 1 (x1, y1) = (r1 · cos θ1, r1 · sin θ1)
Position coordinates of observation point 2 (x2, y2) = (r2, cos θ2, r2, cos θ2)
Here, θ1 is an angle formed by a line connecting the observation point 1 and the target 3 with the X axis, and θ2 is an angle formed by a line connecting the observation point 2 and the target 3 with the X axis. r1 is the distance between the observation point 1 and the target 3, and r2 is the distance between the observation point 2 and the target 3.
When the direction finding error at the observation point 1 is φ1, the direction finding result at the observation point 1 is expressed by a straight line expression as follows.
Observation result at observation point 1 y = a1 · x + b1 (5)
a1 = tan (θ1−φ1)
b1 = r1sin θ1-tan (θ1-φ1) · r1cos θ1
= Y1-tan (θ1-φ1) · x1
θ1-φ1 = Θ1 + 180 °
Θ1: Target search result at observation point 1 (Search result 1)

ｘ’，ｙ’：以下の式を満たす双曲線
ｘ’²/ａ²−ｙ’²/ｂ²＝１
ａ＝（ｒ２−ｒ１）／２＝Ｖc・Δｔ／２
Ｖc：光速 Δｔ：信号到来時間差
ｂ＝（ｃ²−ａ²）^1/2
ｃ＝（（ｘ２−ｘ１）²＋（ｙ２−ｙ１）²）^1/2／２
ξ＝ｔａｎ^-1（（ｙ２−ｙ１）／（ｘ２−ｘ１））
ｘc，ｙc：観測点１及び観測点２の中点の座標 Next, at the observation point 2, a signal arrival time difference Δt between the observation point 1 and the observation point 2 which are time-synchronized using the GPS receivers 16 and 27 is obtained.
Signal arrival time difference Δt = t2−t1
t2: Signal arrival time at observation point 2
t1: Signal arrival time at observation point 1 Using the above signal arrival time difference Δt, a hyperbola with the observation point 1 and the observation point 2 as a focal point is obtained.

x ′, y ′: Hyperbola that satisfies the following formula
x ′ ² / a ² −y ′ ² / b ² = 1
a = (r2-r1) / 2 = Vc · Δt / 2
Vc: speed of light Δt: signal arrival time difference b = (c ² −a ² ) ^1/2
c = ((x2-x1) ² + (y2-y1) ² ) ^1/2 / 2
ξ = tan ⁻¹ ((y2−y1) / (x2−x1))
xc, yc: coordinates of the midpoint of observation point 1 and observation point 2

By obtaining the intersection of the above equations (5) and (6), the target position coordinates (x, y) can be obtained by a combination of the direction finding result and the hyperbolic method.
Therefore, the self-position coordinates (x1, y1) obtained from the self-position calculation unit 12 at the observation point 1, the direction finding result 1 (Θ1) obtained from the target orientation calculation unit 11, and the signal arrival time obtained from the signal arrival time measurement unit 17 The time (t1) is transmitted to the azimuth measuring device 2 at the second observation point by the communication unit 15 via the observation data transfer unit 13 and obtained from the self-position calculating unit 22 of the azimuth measuring device 2 at the second observation point. By using the self-position coordinates (x2, y2) and the signal arrival time 2 (t2) obtained from the signal arrival time measurement unit 28, the target position is determined by the target position determination processing unit 25 of the azimuth measuring apparatus 2 at the observation point 2. Can be standardized.

Usually, the target 3 to be located is in a flight danger area where an aircraft or the like cannot easily fly and enter, so the aircraft A (observation point 1) and the aircraft B (observation point 2) are close to the target. I have to do a search from the direction I did. Therefore, the positioning error is inevitably increased. A calculation example in which the position determination result is simulated will be described with reference to FIG.
As shown in FIG. 8, when the target position is determined by measuring the direction finding and the signal arrival time difference from the direction close to the target 3, the straight line of the direction finding result at the observation point 1 and the observation points 1 and 2. Since the slope of the hyperbola obtained from the signal arrival time difference between them becomes a close value, the distribution of the intersections varies greatly, and the positioning error is large.

Therefore, as shown in FIG. 9, the position location accuracy can be greatly improved by performing the target position location using the reflected wave from the reflection point 5 whose position coordinates are already known. The processing content of the target position determination when the reflection point 5 is used will be described. First, the observation result 1 (Θ1), the self-position coordinates (x1, y1), and the signal arrival time (t1) are obtained at the observation point 1 and transmitted to the observation point 2. Next, the observation point 2 can obtain the same result as that observed from the reflection point 5 equivalently by calculating the signal arrival time difference Δt between the observation points 1 and 2 using the reflected wave from the reflection point 5. it can.
The equivalent signal arrival time t2 ′ is expressed by the following equation.
t2 '= t2-((x3-x2) ² + (y3-y2) ² ) ^1/2 / Vc
Vc: speed of light
x2, y2: Position coordinates of observation point 2
x3, y3: position coordinates of the reflection point (registered in advance in the reflection point information holding unit 29)

以上より反射波を用いて求めた等価的な信号到来時刻（ｔ２’）及び等価的な観測点２の位置座標（ｘ２’，ｙ２’）を、それぞれ信号到来時刻（ｔ２）及び観測点２の位置座標（ｘ２，ｙ２）として反射点がない場合と同じ処理により位置標定を行うことによって、目標に対して離隔した方向（目標からみて互いに直交する方向に近い方向）から方探を行ったのと同様な高い精度での目標位置標定が可能となる。この処理は航空機Ｂ（観測点２）の位置測定装置２の目標位置標定処理部２５で実施する。 The equivalent position coordinates of the observation point 2 are as follows.

As described above, the equivalent signal arrival time (t2 ′) and the equivalent position coordinate (x2 ′, y2 ′) of the observation point 2 obtained using the reflected wave are respectively obtained from the signal arrival time (t2) and the observation point 2. By performing the position determination by the same process as when there is no reflection point as the position coordinates (x2, y2), the direction search was performed from a direction away from the target (a direction close to the direction orthogonal to the target). The target position can be determined with high accuracy similar to the above. This processing is performed by the target position locating processing unit 25 of the position measuring device 2 of the aircraft B (observation point 2).

FIG. 10 shows a calculation example simulating the target position locating result when the reflection point 5 is used for observation from a direction equivalently spaced from the target.
As shown in FIG. 10, by performing observation from a direction that is equivalently separated from the target 3, the inclination of the direction finding result at the observation point 1 and the inclination of the hyperbola calculated at the observation point 2 become nearly perpendicular. For this reason, the variation in the distribution of the intersections is also small, and the target position can be determined with high accuracy.

Embodiment 3
In the first and second embodiments of the present invention, the azimuth measuring device 2 of the aircraft B (observation point 2) receives necessary data from the azimuth measuring device 1 of the aircraft A (observation point 1) by the communication means, and the aircraft B ( The target position locating processing unit 25 included in the azimuth measuring device 2 of the observation point 2) performs the target position locating processing, but the recording unit 14 and the aircraft B (observation) included in the azimuth measuring device 1 of the aircraft A (observation point 1). Since the observation data is recorded in the display recording unit 26 of the azimuth measuring apparatus 2 of point 2), the same effect can be obtained even if the target position locating processing is performed off-line by the target position locating processing apparatus provided on the ground. Can be expected. In this case, since the position coordinates and the reflection surface angle data of the reflection surface 4 or the reflection point 5 are known, this data may be held in advance in a target position locating processing device provided on the ground.
In addition, the necessary data is transmitted from the direction measuring device 1 of the aircraft A (observation point 1) and the direction measuring device 2 of the aircraft B (observation point 2) to a platform other than each observation point by means of communication, and the target is obtained in real time. The same effect can be expected even if the position location processing is performed.

  The present invention can be used when, for example, a position where a target exists is specified by observing a target direction and a target signal arrival time from two observation points (aircraft or the like).

The block block diagram of Embodiment 1 of this invention. Explanatory drawing of the processing content (basic process when not using a reflective surface) in Embodiment 1 of this invention. The figure which shows the calculation example of the position determination result by the observation from the direction which adjoined in Embodiment 1 of this invention. Explanatory drawing of the processing content (process in the case of using a reflective surface) in Embodiment 1 of this invention. The figure which shows the example of a calculation of the position determination result by the observation from the direction distantly equivalent in Embodiment 1 of this invention. The block block diagram of Embodiment 2 of this invention. Explanatory drawing of the processing content (basic processing when not using a reflective point) in Embodiment 2 of this invention. The figure which shows the calculation example of the position determination result by the observation from the direction which adjoined in Embodiment 2 of this invention. Explanatory drawing of the processing content (process in the case of using a reflective point) in Embodiment 2 of this invention. The figure which shows the example of a calculation of the position determination result by the observation from the direction equally separated in Embodiment 2 of this invention.

Explanation of symbols

1: Direction measuring device for first observation point 2: Direction measuring device for second observation point 3: Target 4: Reflecting surface 5: Reflecting point 10: First target radio wave receiver 11: First target direction calculation Unit 12: First self-position calculation unit 13: First observation data transfer unit 14: First recording unit 15: First communication unit 16: First GPS receiver 17: First signal arrival time measurement Unit 20: Second target radio wave reception unit 21: Second target azimuth calculation unit 22: Second self-position calculation unit 23: Second communication unit 24: Reflecting surface information holding unit 25: Second observation data transfer Unit and target location processing unit 26: second recording unit (display recording unit) 27: second GPS receiver 28: second signal arrival time measuring unit 29: reflection point information holding unit

Claims (3)

At least two moving aircraft, at the target position locating system that performs orientation of the target position based on the target azimuth observations from the azimuth measuring device provided to the observation point mounted respectively to ship or vehicle,
A first target radio wave receiving unit that receives radio waves from the target, a first target azimuth calculating unit that calculates a target azimuth using the target radio wave received by the first target radio wave receiving unit, A first self-position calculation unit that calculates coordinates, a first search result 1 obtained by the first target azimuth calculation unit, and a first position coordinate data obtained by the first self-position calculation unit are transferred. Observation data transfer unit, direction finding result 1 from the first observation data transfer unit and a first recording unit for recording data of the self-position coordinates, and direction finding result from the first observation data transfer unit A first observation point azimuth measuring apparatus provided with a first communication unit for transmitting data of 1 and the self-position coordinates to a second observation point azimuth measuring apparatus described later;
A second target radio wave receiving unit that receives a radio wave radiated from the target and reflected by a known reflecting surface, and a second target that calculates a target azimuth using the target radio wave received by the second target radio wave receiving unit An azimuth calculation unit, a second self-position calculation unit that calculates coordinates of the position of the aircraft, a direction finding result 2 obtained by the second target azimuth calculation unit, and a self obtained by the second self-position calculation unit A second observation data transfer unit that transfers position coordinate data; a second recording unit that records the direction finding result 2 from the second observation data transfer unit and self-position coordinate data; and the first A second communication unit that receives data of the direction finding result 1 and the self-position coordinates from the communication unit; a reflection surface information holding unit that holds in advance information on the position coordinates of the reflection surface and the angle of the reflection surface; Direction finding result 1 (Θ1) from the second communication unit and self-position coordinates (x , Y1), the direction finding result 2 (Θ2) and the self-position coordinates (x2, y2) from the second observation data transfer unit, and the reflection surface position coordinates (x3, y3) from the reflection surface information holding unit An azimuth measuring device for a second observation point that is provided with a target position locating processing unit that performs arithmetic processing based on the reflection surface angle (Θ3) and performs locating of the target position,
The angle formed between the target azimuth of the azimuth measuring device at the first observation point and the target azimuth of the azimuth measuring device at the second observation point is measured from a direction closer to a right angle than when there is no reflecting surface. A target position locating device characterized by that.   The target position locating apparatus according to claim 1, wherein the second position observation device is provided with a display recording section for recording data information input to the target position locating processing section and displaying a target position locating result to the user. . At least two moving aircraft, at the target position locating system that performs orientation of the target position based on the target azimuth observations from the azimuth measuring device provided to the observation point mounted respectively to ship or vehicle,
A first target radio wave receiving unit that receives radio waves from the target, a first target azimuth calculating unit that calculates a target azimuth using the target radio wave received by the first target radio wave receiving unit, A first self-position calculation unit that calculates coordinates, a first search result 1 obtained by the first target azimuth calculation unit, and a first position coordinate data obtained by the first self-position calculation unit are transferred. A first observation point azimuth measuring apparatus comprising: an observation data transfer unit; and a first recording unit that records data of the direction finding result 1 and the self-position coordinates from the first observation data transfer unit,
A second target radio wave receiving unit that receives a radio wave radiated from the target and reflected by a known reflecting surface, and a second target that calculates a target azimuth using the target radio wave received by the second target radio wave receiving unit An azimuth calculation unit, a second self-position calculation unit that calculates coordinates of the position of the aircraft, a direction finding result 2 obtained by the second target azimuth calculation unit, and a self obtained by the second self-position calculation unit A second observation data transfer unit that transfers position coordinate data; and a second recording unit that records a direction finding result from the second observation data transfer unit and data of the self-position coordinates. Azimuth measuring device
A target position locating processing unit which is provided on the ground and inputs data from the first recording unit and the second recording unit;
The angle formed between the target azimuth of the azimuth measuring device at the first observation point and the target azimuth of the azimuth measuring device at the second observation point is measured from a direction closer to a right angle than when there is no reflecting surface. Place and
And wherein the target position location processing unit for performing arithmetic processing on the basis of said input data said the position coordinates of the reflecting surface (x3, y3) and the reflection surface angle (.THETA.3), and to perform orientation of the target position Target position locating device.

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