JPH0776788B2 - Aircraft flight position detector - Google Patents

Description

The present invention relates to an aircraft flight position detection device, and is particularly suitable for application when measuring the flight position of an aircraft from the ground.

[Outline of Invention]

According to the present invention, in an aircraft flight position detection device using a microphone, a cross-correlation function calculation is executed with reference data based on subtraction data of an elevation angle detection input signal and a passage detection input signal. The calculation means can be further simplified.

[Conventional technology]

As shown in FIG. 4 as a conventional flight position detecting device for an aircraft, right and left detectors 3R and 3L are arranged across a route 2 of an aircraft 1, and the route is passed through these right and left detectors 3R and 3L. When the aircraft 1 passes through a measurement plane 4 which is a virtual plane that crosses the plane 2, the elevation angles θ _R and θ _L when the aircraft 1 is viewed from the right and left detectors 3R and 3L are proposed to be calculated. (“Acoustic Positioning of Aircraft”, Hidefumi Obata, Kan Ishii, Juichi Igarashi,
Space Aerospace Laboratory Report Vol. 9, No. 4, Supplement, October 1973, University of Tokyo).

This aircraft flight position detection device utilizes the fact that the noise generated by the aircraft 1 flying on the route 2 is converted into an electric signal by three microphones, and the cross-correlation of each electric signal changes with the passage of time. Then, the time when the aircraft passes through the measurement plane 4 and the elevation angles θ _R and θ _L at that time can be calculated. For example, the flight path of the aircraft 1 taking off from the runway 5 is monitored with sufficient accuracy for practical use. it can.

[Problems to be solved by the invention]

Conventionally, an aircraft flight position detecting device that realizes such a principle has a configuration shown in FIG.

In FIG. 5, the right and left detectors 3R and 3L are the first and second microphones in the height direction (that is, the Z-axis direction).
The MICU and MICL are arranged so as to keep a predetermined distance, and either one of them, for example, at the same height position as the second microphone MICL arranged at the lower position, in the extension direction of the route 2 (that is, the X-axis). The third microphone MICH is arranged so as to keep a predetermined distance along the direction).

The microphones MICU, MICL, and MICH convert the aircraft noises NU, NL, and NH generated in the aircraft 1 into electrical noise detection signals S _U , S _L, and S _H , respectively, and detect signal operation device unit 6
Are input to the elevation angle detection and passage detection cross-correlation function calculation units 7 and 8, and the cross-correlation function values generated over time are sequentially calculated.

In addition to the fact that the aircraft noise generated in the aircraft 1 is not uniform over time, the aircraft noise is also transmitted to the microphones MICU, MICL and MICH.
, And NH, a time delay corresponding to the distance between the aircraft 1 and each of the microphones MICU, MICL, and MICH occurs, and the cross-correlation function value reaches the maximum value by the time delay (that is, the same). The timing at which aircraft noise arrives) will shift.

Therefore, firstly, the first and second microphones MICU and MI
The time delay from the reference time point of the position where the cross-correlation function of the noise detection signals S _U and S _L of CL takes the maximum value is the height direction from the aircraft 1 to the first and second microphones MICU and MICL.
It represents the difference in the distance to the elevation angle θ _R using the trigonometric function from the data showing the time delay and the microphone interval.
(Or θ _L ) can be obtained.

Secondly, the second and third microphones MICL and MICH
The time delay from the reference time until the cross-correlation is obtained for the noise detection signals S _L and S _H of is the difference in the distance from the aircraft 1 to the second and third microphones MICL and MICH in the traveling direction of the aircraft 1. Therefore, if the aircraft noises NL and NH generated in the aircraft 1 reach the second and third microphones MICL and MICH at the same time, the noise detection signal S _L When the position where the cross-correlation function of S _H and S _H has the maximum value coincides with the reference time point, it can be determined that the time point at which the aircraft 1 has passed the measurement plane 4 (FIG. 4).

Based on such a principle, the passage detection cross-correlation function calculation unit 8 executes the cross-correlation calculation processing at predetermined time intervals as the time t elapses, as shown in FIG. Time delay τ (ms) within a predetermined range, for example -12.8 (m
s] to +12.8 [ms], the cross-correlation function curve information INF11 consisting of a large number of cross-correlation function curve groups of the cross-correlation function values obtained is obtained.

As shown in FIG. 6B, the elevation angle detection cross-correlation function calculation unit 7 executes similar calculation processing on the same time axis as the calculation time axis of the passage detection cross-correlation function calculation unit 8. Obtain the cross-correlation function curve information INF12.

Here, in the cross-correlation function curve information INF11 obtained by the cross-detection cross-correlation function calculation unit 8, the peak representing the maximum value in each cross-correlation function curve (the time delay τ when the peak occurs)
Therefore, the mountain range curve portion MT11 is formed such that the position of the aircraft 1 on the route 2 is continuously connected by the cross-correlation function curves that are adjacent to each other as time passes.
When the position of the time delay τ of 11 crosses the reference line τ = 0, it can be represented that the aircraft 1 has passed the measurement plane 4 at that time.

On the other hand, in the cross-correlation function curve information INF12 obtained in the elevation-angle-detecting cross-correlation function calculating unit 7, there is a mountain range curve unit MT12 in which the peaks representing the maximum values of the respective cross-correlation function curves are connected over time. Is formed, so that the reference line τ =
The deviation from 0 to the value of the time delay τ of the mountain range curve portion MT12 represents the change in the elevation angle θ _R or θ _L.
A state in which MT12 approaches the reference τ = 0 indicates that the elevation angle is small (in other words, the aircraft 1 is located farther than the measurement plane 4), and at the same time, the mountain range curve section MT12 indicates the reference line τ = 0. This means that the angle of elevation increases as the distance increases (in other words, the state is approaching the measurement plane 4).

In this way, the cross-correlation function curve information INF11 and INF12 obtained in the cross-detection cross-correlation function calculation unit 8 and the elevation-angle detection cross-correlation function calculation unit 7 are respectively the pass-rate evaluation unit 9
And FIG. 7 (A) and (B) given to the elevation evaluation unit 10.
As shown in, the mountain range curve part MT of each cross-correlation function curve
Extraction curve MT by extracting the position of each mountain forming 11 and MT12
In addition to obtaining 21 and MT22, the passage evaluation unit 9 evaluates the time when the extraction curve MT21 crosses the reference line τ = 0 and gives the evaluation output DET1 to the elevation angle evaluation unit 10 to evaluate the extraction curve MT22. The elevation angle corresponding to the time point when the output DET1 is obtained is evaluated as the elevation angle when the aircraft 1 crosses the measurement plane 4, and the evaluation output DET2 is output to the detection signal S of the detection signal arithmetic unit 6 through the output circuit 11. _Send as _DET .

By doing so, the elevation angle calculation data can be obtained based on the evaluation result of whether or not the aircraft 1 has passed the measurement plane 4, and thus the elevation angle on the measurement plane 4 and thus the flight position of the aircraft 1 can be obtained. You can

However, according to this conventional configuration, in addition to the passage detection mutual transfer function calculation unit 8 for evaluating the time when the aircraft 1 passes through the measurement plane 4 as the mutual transfer function calculation unit, the elevation angle on the measurement plane 4 is calculated. Since it is necessary to separately provide the elevation angle detection cross-correlation function calculation unit 7 for evaluation, there is an unavoidable problem in that the configuration of the entire aircraft flight position detection device becomes large.

Actually, since the cross-correlation function calculation circuit requires a relatively large-scale multiplication circuit, if the calculation amount of the cross-correlation function increases, the structure of the cross-correlation function calculation unit becomes large and the calculation time increases. Become long.

The present invention has been made in view of the above points, and an object thereof is to propose an aircraft flight position detection device capable of further reducing the scale of the cross-correlation function calculation unit.

[Means for solving problems]

In order to solve such a problem, in the present invention, in the measurement plane (4) where the passage of the aircraft (1) is to be detected,
A reference direction microphone (MICL) is used as a reference, and an elevation angle detection microphone (MICU) arranged in a first direction (Z direction) that is above or below and a second direction orthogonal to the first direction (Z direction). Elevation angle detection input signal (M _U ) and passage detection which are obtained from the microphone (MICH) for passage detection arranged in (X direction) and the microphone (MICL) for elevation angle detection, and which has elevation angle information of the aircraft (1) The elevation detection input signal (M _U ) and the passage detection input signal (M _U ) are obtained based on the passage detection input signal (M _H ) obtained from the microphone (MICH) and having the passage information to the measurement plane (4) of the aircraft (1). By receiving one of M _H ) as the first input signal at the addition input end and the other at the subtraction input end as the second input signal, the elevation angle detection input signal (M _U ) and the passage detection input signal subtracting processing (M _H) Calculation means (26), subtracting means (2
The cross-correlation function between the subtracted signal (D _SUB ) obtained from 6) and the reference input signal (M _L ) obtained from the reference microphone (MIC _L ) is calculated to obtain the first input signal (M _U (or
M _H )) and the reference input signal (M _L ), the first cross-correlation output representing the positive value of the cross-correlation by the maximum value, and the second input signal (M _H (or M _U )) and the reference input signal (M _L) the cross-correlation function calculation means for obtaining calculating output (INF20) and a second cross-correlation output representing Te cowpea correlation to the negative minimum value of (28)
And the passage of the measurement plane (4) of the aircraft (1) from the first (or second) cross-correlation output obtained based on the passage detection input signal (M _H ) of the first and second cross-correlation outputs. The time point is determined, and the elevation angle (θ _R , θ _L ) at the time point (t _CRS ) of the measurement plane (4) of the aircraft (1) is determined from the second (or first) cross-correlation output corresponding to the determination result. A determination means (40, 42) for determination is provided.

[Action]

The subtraction data D _SUB obtained from the subtraction means 26 includes a passage detection input signal M _H (or an elevation angle detection input signal M _U ) whose phase is inverted as a subtraction input, and an elevation angle detection input signal M _U (where the phase is not inverted). Or a passage detection input signal M _H ) as a combined signal component.

Therefore, the cross-correlation function output INF20 obtained from the cross-correlation function calculation means 28 is the phase-inverted passage detection input signal M _H ,
A cross-correlation can be taken at the same time as the elevation angle detection input signal M _U (or the passage detection input signal M _H ) which is not phase-inverted, and thus the cross-correlation function calculating means 28 for passing position detection and elevation angle detection is not provided separately. It is sufficient to provide only one in common, and the configuration of the cross-correlation function calculating means can be further simplified by this amount.

〔Example〕

 An embodiment of the present invention will be described in detail with reference to the drawings.

[1] First Embodiment In FIG. 1, 20 indicates an aircraft flight position detecting device as a whole, and under the control of a control circuit 21, a first, a second, a third
The microphones MICU, MICL and MICH (Fig. 4) are used as an elevation angle detection microphone, a reference microphone and a passage detection microphone, respectively.
Noise detection signals S _U , S _L, and S _H obtained from MICU, MICL, and MICH are respectively filtered by filters 23, 24 of the cross-correlation function calculation unit 22.
And 25 as the elevation angle detection input signal M _U , the reference input signal M _L, and the passage detection input signal M _H.

The elevation angle detection input signal M _U obtained from the first elevation angle detection microphone MICU is given to the addition input terminal of the subtraction circuit 26, and the passage detection input signal M _H of the passage detection third microphone MICH is subtracted. given to the subtraction input of 26, converted into the following equation M _SUB = M _U -M _H ...... subtraction data D _SUB subtraction output M _SUB of the subtraction circuit 26 represented by (1) in the analog / digital conversion circuit 27 It is then supplied to the cross-correlation function calculation circuit 28 as the first input data.

At the same time, the reference input signal M _L of the second reference microphone MICL is directly converted into the digital data D _L in the analog / digital conversion circuit 29 and the N-stage delay circuit is provided.
After being delayed by a predetermined amount in 30, the reference data D _REF is supplied to the cross-correlation function operation circuit 28 as the second input data.

The cross-correlation function calculation circuit 28 calculates the cross-correlation function of the first and second input data, that is, the subtraction data D _SUB and the reference data D _REF , with a time delay τ within a predetermined range (-12.8 to +12.8 [ms]). For the cross correlation function curve information INF20 as shown in FIG.

Here, the N-stage delay circuit 30 moves the reference line τ = 0 to the center of the range τ = −12.8 to +12.8 [ms] of the cross-correlation function curve by adjusting the time delay of the reference data D _REF in advance. Thus, the time delay τ can be expressed in the positive and negative directions centering on the reference line τ = 0.

The subtraction data D _SUB supplied as the first input signal to the cross-correlation function calculation circuit 28 is obtained by subtracting the passage detection input signal M _H from the elevation angle detection input signal M _U as shown in equation (1). The obtained signal includes the elevation angle detection information represented by the elevation angle detection input signal M _U , and at the same time, a signal obtained by inverting the phase of the passage detection input information M _H as the passage detection information. Is meant to include.

Therefore, when the cross-correlation function calculation circuit 28 calculates the cross-correlation function value, the subtraction data D _{SUB is} substantially obtained by the calculation operation.
Of these, the data component of the elevation detection input signal M _U and the reference data D
By calculating the cross-correlation function with _REF , a cross-correlation calculation curve that maximizes the positive value when the cross-correlation is obtained between the reference input signal M _L and the elevation angle detection input signal M _U is obtained. Of the subtraction data D _{SUB and} the phase of the subtraction data is inverted at the same time
By calculating the cross-correlation function between the M _H data component and the reference data D _REF , the passage detection input signal M _H and the reference input signal
It is possible to obtain a calculation result that exhibits a cross-correlation calculation curve that has a minimum value in the negative direction when a cross-correlation is obtained with M _L.

Thus, the cross-correlation function curve information INF20 (FIG. 2) obtained in the cross-correlation function calculation circuit 28 includes the mountain range curve section MT30 obtained by the cross-correlation with the elevation angle detection input signal M _U.
And a valley curve portion VL30 in which a valley is formed by cross-correlation with the passage detection input signal M _H can be formed by one cross-correlation function calculation.

In this way, the cross-correlation function curve information INF20 obtained from the cross-correlation function calculation circuit 28 is the minimum position maximum position detection unit 34.
To the minimum position detection circuit 35 and the maximum position detection circuit 36, and detect the time delay detection signals τ _MIN and τ _MAX that are the minimum value and the maximum value of each cross-correlation function curve, and set the threshold circuit 37 respectively. Through the minimum position storage circuit of the passage determination unit 40
41 and the maximum position storage circuit 43 of the elevation angle determination unit 42.

Thus, in the minimum position storage circuit 41 and the maximum position storage circuit 43, as shown in FIG. 3, the minimum position data τ _MIN in each cross-correlation function curve is arranged according to the passage of time t, and the passing data extraction curve VL40 is formed. And the elevation data extraction curve MT40 formed by arranging the maximum position data τ _MAX for each cross-correlation function curve are held.

The minimum position data D _MIN of the maximum position storage circuit 41 is the time t at which the cross point detection circuit 44 crosses the reference line τ = 0.
_CRS (Fig. 3) is detected, and the maximum position data corresponding to the intersection time t _CRS in the elevation angle data extraction curve MT40 held in the maximum position storage circuit 43 is detected by the cross point detection data D _CRS. The output data D _MAX consisting of τ _MAX is supplied to the elevation angle calculation circuit 45.

The elevation angle calculation circuit 45 is The elevation angle θ is calculated according to, and the elevation angle data representing the elevation angle θ is calculated.
D _ELV is output to the output circuit 46.

Thus, the output circuit 46 outputs the flight position detection data DATA when the aircraft 1 passes through the measurement plane 4 and when the aircraft 1 is viewed from the right or left side detector 3R or 3L (FIG. 4), the elevation angle θ _R or θ _L. Can be sent as.

In the above configuration, for example, when the aircraft 1 that has taken off the runway 5 (FIG. 4) approaches the measurement plane 4 through the route 2, the movement of the aircraft 1 in the track direction is changed from the second microphone MICL. When the time delay of the noise detection signal S _H obtained from the third microphone MICH changes with reference to the obtained noise detection signal S _L , the cross-correlation function calculation circuit 28
Takes a correlation with the phase-inverted passage detection input signal M _H of the subtraction data D _SUB to generate a valley curve portion VL30 (FIG. 2) in the cross-correlation function curve information INF20.

The valley curve portion VL30 is detected by the minimum position detection circuit 35, and the minimum position data τ _MIN obtained at the output end thereof is stored in the minimum position storage circuit 41 through the threshold circuit 37.

Here, the threshold circuit 37 is a vehicle in the vicinity of the right or left detector 3R or 3L, when noise such as a bark of a dog occurs,
It has a threshold value that does not detect these noises as data.

On the other hand, the noise detection signal S _U of the first microphone MICU
The elevation angle detection input signal M _U obtained by the subtraction data D _SUB
Is supplied to the cross-correlation function calculation circuit 28 as data whose phase is not inverted, and accordingly, the cross-correlation function calculation circuit 28 adds the cross-correlation function curve information INF20 to the mountain range curve section MT30 (second
) Is generated, and this is detected by the maximum position detection circuit 36 and written in the maximum position storage circuit 43 via the threshold value circuit 37.

Therefore, the time delay of the noise detection signal S _U of the first microphone MICU with respect to the reference noise detection signal S _L increases as the aircraft 1 approaches the measurement plane 4 and passes through the measurement plane 4 accordingly. After that, as it goes away from the measurement plane 4, it becomes smaller accordingly.

When the minimum position data D _MIN written in the minimum position storage circuit 41 crosses the reference line τ = 0, the cross point detection circuit 44 detects this and detects the cross point detection data.
The maximum position data D _MAX corresponding to the time point t _CRS designated by the D _CRS is read from the maximum position storage circuit 43 to the elevation angle calculation circuit 45, and thus the maximum position data D at the time when the aircraft 1 passes the measurement plane 4. Output _MAX to the elevation angle calculation circuit 45.

Therefore, according to the above-described configuration, the elevation angle data at the timing when the aircraft 1 has passed the measurement plane 4 can be evaluated with certainty. It suffices to provide only one cross-correlation function calculation circuit 28 that is common to the elevation angle detection operation at this time, and the configuration of the cross-correlation function calculation unit 22 can be remarkably reduced in size.

[2] Other Embodiments (1) In the above embodiments, the case where the lower microphone MICL of the elevation angle detecting microphones MICU and MICL is used as the reference microphone has been described.
Alternatively, the upper microphone MICU can be used to obtain the same effect as the above case.

(2) In the above-described embodiment, the case where the passage detection input signal M _H is input to the subtraction input end when performing the subtraction processing in the subtraction circuit 26 has been described, but instead of this, the elevation angle detection input signal is input. Even if M _U is input to the subtraction input end and the passage detection input signal M _H is input to the addition input end, the same effect as the above case can be obtained.

(3) In the above-described embodiment, the subtraction data D _SUB is calculated and the cross-correlation function curve information IN is calculated by the hardware circuit configuration.
Although the calculation of F20, the processing of the passage determination unit 40 and the elevation angle determination unit 42, and the like are executed, instead of this, they may be executed by software means.

〔The invention's effect〕

As described above, according to the present invention, the cross-correlation function between the subtraction data between the elevation detection input signal and the passage detection input signal and the reference data is calculated. The functions can be calculated all at once using the function calculation means, and the entire structure can be further simplified.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of an aircraft flight position detection apparatus according to the present invention, FIGS. 2 and 3 are characteristic curve diagrams showing cross-correlation function curve information and data extraction curves, and FIG. 4 is an aircraft. FIG. 5 is a schematic perspective view for explaining the principle of the flight position detecting device, FIG. 5 is a block diagram showing a conventional aircraft flight position detecting device, and FIGS. 6 and 7 are cross-correlation function curves in the case of FIG. It is a characteristic curve figure which shows information and a data extraction curve. 20 ... Aircraft flight position detection device, 22 ... Cross-correlation function calculation unit, 26 ... Subtraction circuit, 28 ... Cross-correlation function calculation circuit,
35, 36 …… Minimum position, maximum position detection circuit, 41,43 …… Minimum position, maximum position storage circuit, 44 …… Cross point detection circuit, 45 …… Elevation angle calculation circuit, MICU, MICL, MICH …… Elevation angle detection circuit , Reference, and passage detection microphones.

Claims (1)

[Claims] 1. A microphone for elevation angle detection, which is arranged in a first direction which is upward or downward with respect to a reference microphone, and which is orthogonal to the first direction in a measurement plane in which passage of an aircraft is to be detected. A passage detection microphone arranged in a second direction, an elevation detection input signal obtained from the elevation detection microphone and having elevation information of the aircraft, and an elevation detection input signal obtained from the passage detection microphone to the measurement plane of the aircraft. One of the elevation angle detection input signal and the passage detection input signal based on the passage detection input signal having passage information of
Is obtained from the subtraction means by subtracting the elevation angle detection input signal and the passage detection input signal by receiving the other input as the second input signal at the addition input end and the other as the second input signal at the subtraction input end. A first cross-correlation representing the cross-correlation between the first input signal and the reference input signal by a positive maximum value by obtaining a cross-correlation function between the subtracted signal and the reference input signal obtained from the reference microphone. Cross-correlation function calculation means for obtaining a calculation output including an output and a second cross-correlation output that represents the cross-correlation of the second input signal and the reference input signal by a negative minimum value; Of the two cross-correlation outputs, the passage time of the aircraft on the measurement plane is determined from the first (or second) cross-correlation output obtained based on the passage detection input signal, and the determination result is determined. Aircraft flight position detecting device characterized by comprising a determination means for determining the elevation angle from the cross-correlation output in the pass time of the measurement plane of the aircraft corresponding to the second (or first) to.