JPH10170624A - Aircraft flight position detecting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect a flight position of an aircraft at observing point of one place by calculating a distance between the observing point and the aircraft from a time difference between a sound wave and a radio wave, and performing an operation on a position of the aircraft from an azimuth angle and an elevation angle of a sound. SOLUTION: A sound from an aircraft is detected by a sound wave system azimuth angle and elevation angle discriminating device 1, and an azimuth angle signal α m according to an azimuth of the aircraft and an elevation angle signal βm according to an elevation angle are measured. A radio wave system position discriminating device 2 outputs an azimuth angle signal α a according to an azimuth of the aircraft by detecting a radio wave emitted by the aircraft. A time difference detecting part 3 finds a time difference (td) between the azimuth angle signal αm of a sound wave and the azimuth angle signal α a of a radio wave, and when the time difference (td) continues on the same value for a prescribed time or more, a judging part 4 judges that a sound source and a radio wave source are the same with each other (the same aircraft). Next, a flight position operation part 5 calculates a distance L between an observing point and the aircraft by multiplying the time difference (td) and sound speed together, and performs an operation on a position of the aircraft from the azimuth angle signal αm and the elevation angle signal βm of the sound.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an aircraft flight position detecting device capable of measuring the flight position of an aircraft from the ground.

[0002]

2. Description of the Related Art Conventionally, as a flight position detection device for an aircraft, a detection device is disposed on the left and right sides of the flight route of the aircraft, and the measurement plane, which is a virtual plane crossing the flight route through the left and right detection devices, is used by the aircraft. When passing, an elevation angle when the aircraft is viewed from the left and right detection devices is calculated by an operation ("Aircraft position localization by acoustic method",
Hidefumi Obata, Yasushi Ishii, and Juichi Igarashi, JAXA, Vol. 9, No. 4, Separate Volume, October 1973, published by The University of Tokyo.)

[0003] In addition, an aircraft flight is arranged in which a detection device provided with microphones is arranged on the left and right sides of the aircraft route, the sound velocity is calculated from detection information obtained from the microphones, and the elevation angle is calculated based on the calculation result. A position detecting device has been proposed (Japanese Patent Publication No. 7-76789).

[0004]

However, in the prior art, since a pair of observation points must be provided on both sides of the route of the aircraft, there is a problem that the installation place of the detection device is limited.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and an object of the present invention is to provide an aircraft capable of detecting the flight position of an aircraft at one observation point. It is intended to provide a flight position detecting device.

[0006]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, a first aspect of the present invention is to detect a sound emitted from an aircraft and output an azimuth signal according to the azimuth of the aircraft and an elevation signal according to the elevation of the aircraft. Sound wave type azimuth and elevation angle identification means, radio wave type azimuth angle identification means for detecting radio waves emitted by an aircraft and outputting an azimuth signal corresponding to the direction of the aircraft, and azimuth by the sound wave type azimuth and elevation angle identification means. A time difference detecting means for outputting a time difference between the angle signal and the azimuth signal by the radio wave type azimuth discriminating means; and determining that the sound source and the radio wave source are the same when the time difference continues to be the same value for a predetermined time or more. Determination means; and flight position calculation means for calculating the distance between the observation point and the aircraft by multiplying the time difference by the speed of sound and calculating the position of the aircraft from the azimuth signal and the elevation signal by sound.

According to a second aspect of the present invention, there is provided a sound wave type azimuth discriminating means for detecting a sound emitted from an aircraft and outputting an azimuth signal according to the direction of the aircraft, and detecting a radio wave emitted from the aircraft to determine the direction of the aircraft. Radio-wave azimuth and elevation identification means for outputting an azimuth signal according to and an elevation signal according to the elevation of the aircraft,
A time difference detecting means for outputting a time difference between the azimuth signal by the sound wave type azimuth discriminating means and the azimuth signal by the radio wave azimuth angle and the elevation angle discriminating means, if the time difference continues the same value for a predetermined time or more, Determination means for determining that the sound source and the radio wave source are the same; and a flight for calculating the distance between the observation point and the aircraft by multiplying the time difference by the speed of sound and calculating the position of the aircraft from the azimuth signal and the elevation signal by radio waves. It has a position calculating means.

According to a third aspect of the present invention, there is provided a sound wave type azimuth / elevation discriminating means for detecting a sound emitted from an aircraft and outputting an azimuth signal according to the azimuth of the aircraft and an elevation signal according to the elevation of the aircraft, and an aircraft. Radio wave type azimuth identification means for detecting a radio wave emitted by and outputting an azimuth signal according to the azimuth of the aircraft;
A cross-correlation function calculating means for calculating a cross-correlation function between the azimuth signal by the acoustic azimuth and elevation angle discriminating means and the azimuth signal by the radio wave azimuth discriminating means; and a position where the maximum value of the cross-correlation function is the same. And a determining means for determining that the sound source and the radio wave source are the same when the sound source and the radio wave source are the same. And flight position calculation means for calculating the distance between the observation point and the aircraft by multiplying by the azimuth angle signal and the elevation angle signal by sound.

According to a fourth aspect of the present invention, there is provided a sound wave type azimuth discriminating means for detecting a sound emitted from an aircraft and outputting an azimuth signal corresponding to the azimuth of the aircraft, and detecting a radio wave emitted from the aircraft to determine the azimuth of the aircraft. Radio-wave azimuth and elevation identification means for outputting an azimuth signal according to and an elevation signal according to the elevation of the aircraft,
A cross-correlation function calculating means for calculating a cross-correlation function between the azimuth signal from the acoustic azimuth discriminating means and the azimuth signal from the radio wave azimuth and elevation angle discriminating means; and a position where the maximum value of the cross-correlation function is the same. And a determining means for determining that the sound source and the radio wave source are the same when the sound source and the radio wave source are the same. And a flight position calculating means for calculating the distance between the observation point and the aircraft by multiplying the distance and calculating the position of the aircraft from the azimuth signal and the elevation signal by radio waves.

According to a fifth aspect of the present invention, there is provided a sound wave type azimuth and elevation discriminating means for detecting a sound emitted from an aircraft and outputting an azimuth signal corresponding to the azimuth of the aircraft and an elevation signal according to the elevation of the aircraft, and an aircraft. Radio wave type azimuth identification means for detecting a radio wave emitted by and outputting an azimuth signal according to the azimuth of the aircraft;
The azimuth signal from the acoustic azimuth and elevation angle discriminating means and the azimuth signal from the radio wave azimuth discriminating means are treated as two-dimensional line drawings of time and azimuth, and the similarity between these two line drawings is determined by pattern matching. The pattern matching means to be evaluated, and the distance between the observation point and the aircraft is calculated by multiplying the delay time of the sound azimuth signal with respect to the azimuth signal of the radio wave giving the maximum value of the cross-correlation function by the pattern matching means by the speed of sound. A flight position calculating means for calculating a position of the aircraft from the azimuth signal and the elevation signal by sound;

According to a sixth aspect of the present invention, there is provided a sound wave type azimuth discriminating means for detecting a sound emitted from an aircraft and outputting an azimuth signal according to the azimuth of the aircraft, and detecting a radio wave emitted from the aircraft to determine the azimuth of the aircraft. Radio-wave azimuth and elevation identification means for outputting an azimuth signal according to and an elevation signal according to the elevation of the aircraft,
The azimuth signal from the sound wave type azimuth discriminating means and the azimuth signal from the radio wave azimuth and elevation angle discriminating means are treated as two-dimensional line drawings of time and azimuth, and the similarity between these two types of line drawings is determined by pattern matching. The pattern matching means to be evaluated, and the distance between the observation point and the aircraft is calculated by multiplying the delay time of the sound azimuth signal with respect to the azimuth signal of the radio wave giving the maximum value of the cross-correlation function by the pattern matching means by the speed of sound. And a flight position calculating means for calculating the position of the aircraft from the azimuth signal and the elevation signal by radio waves.

[0012]

Embodiments of the present invention will be described below with reference to the accompanying drawings. Here, FIG. 1 is a configuration diagram of an aircraft flight position detection device according to the first aspect of the invention, FIG. 2 is a configuration diagram of a sound wave type azimuth and elevation angle identification device, FIG. 3 is an explanatory diagram showing an arrangement of microphones, and FIG. FIG. 5 is an explanatory view showing the arrangement of antennas, FIG. 6 is a view showing a difference in change in azimuth angle between radio waves and sound, and FIG. 7 is an aircraft flight position according to the invention of claim 1. FIG. 8 is a configuration diagram of an aircraft flight position detection device according to the third aspect of the present invention, FIG. 9 is a configuration diagram of an aircraft flight position detection device according to the fifth aspect of the invention, and FIG. FIG. 11 is a diagram in which the azimuth at which a radio wave arrives is pixelated, and FIG. 12 is a diagram in which the azimuth at which a certain sound arrives is pixelated.

As shown in FIG. 1, the aircraft flight position detecting device of the first aspect detects a sound emitted from an aircraft and generates an azimuth signal αm corresponding to the azimuth of the aircraft and an elevation signal βm corresponding to the elevation of the aircraft. Output sound wave type azimuth and elevation angle identification device 1
A radio wave direction identification device 2 that detects a radio wave emitted by the aircraft and outputs an azimuth signal αa corresponding to the direction of the aircraft,
The time difference detector 3 that outputs the time difference td between the azimuth signal αm of the sound wave type azimuth and elevation angle identification device 1 and the azimuth signal αa of the radio wave type azimuth identification device 2, and the time difference td has kept the same value for a predetermined time or more. In this case, the determination unit 4 determines that the sound source and the radio wave source are the same, calculates the distance L between the observation point and the aircraft by multiplying the time difference td by the speed of sound, and calculates the aircraft L from the azimuth signal αm and the elevation signal βm by sound. And a flight position calculation unit 5 for calculating the position of.

The sound wave type azimuth and elevation angle discriminating apparatus 1 is shown in FIG.
, Four omnidirectional microphones M1, M
2, M3, M4, a correlation calculator E1 for calculating a correlation function between the output signal of the microphone M1 and the output signal of the microphone M2, and a correlation calculator for calculating a correlation function between the output signal of the microphone M1 and the output signal of the microphone M3. E2
A correlation operation unit E3 that calculates a correlation function between the output signal of the microphone M1 and the output signal of the microphone M4; a delay detection unit D1 that calculates a delay time τx of the output signal of the microphone M2 with respect to the output signal of the microphone M1; A delay detection unit D2 for obtaining a delay time τy of the output signal of the microphone M3 with respect to the output signal of the microphone M3, a delay detection unit D3 for obtaining a delay time τz of the output signal of the microphone M4 with respect to the output signal of the microphone M1, and delay times τx, τy, An azimuth / elevation angle calculation unit P1 calculates the azimuth angle αm and the elevation angle βm of the aircraft from τz.

Four omnidirectional microphones M1, M2,
As shown in FIG. 3, M3 and M4 are arranged such that a straight line connecting the microphone M1 and the microphone M2, a straight line connecting the microphone M1 and the microphone M3, and a straight line connecting the microphone M1 and the microphone M4 are orthogonal to each other. .

The microphone M1 and the microphone M
2, the distance between the microphone M1 and the microphone M3, and the distance between the microphone M1 and the microphone M4 are each 1 m. In addition, the said distance does not necessarily need to be 1 m. In short, it is only necessary that sound from the direction in which the microphone M1 looks at the microphone M2 (M1 direction and M2 direction) does not reach the microphones M1 and M2 at the same time, and the direction in which the microphone M1 looks at the microphone M3 (M1 direction and M3 direction). Sound from microphone M1
This is because it is only necessary that the sound from the direction in which the microphone M1 looks at the microphone M4 (M1 and M4 directions) does not reach the microphone M1 and the microphone M4 at the same time. When the M1 and M4 directions are aligned in the vertical direction and the azimuth is detected in an absolute direction, the M1 and M2 directions or the M1 and M3 directions may be adjusted to any one of north, south, east and west.

For example, the M1 · M2 direction is 0 °, the M1 · M
If the three directions are 90 °, the microphones M1, M2, M
The azimuth αm of the aircraft, which is the sound source of the sound captured in Step 3, is obtained by the azimuth elevation calculator P1 as follows.

When τx ≧ 0 and τy ≧ 0, αm =
tan ^-1 (τy ÷ τx) [radian].

When τx <0, αm = π + tan ⁻¹
(Τy ÷ τx) [radian].

When τx ≧ 0 and τy <0, αm =
2π + tan ⁻¹ (τy ÷ τx) [radian].

The microphones M1, M2, M3, M
The elevation angle βm of the aircraft, which is the sound source of the sound captured in step 4, is obtained by the azimuth elevation angle calculation unit P1 as follows.

[0022]

(Equation 1)

Next, as shown in FIG. 4, the radio wave direction identification device 2 has three vertical antennas (omnidirectional in a horizontal plane).
A1, A2, and A3, amplification sections A4, A5, and A6 that amplify output signals of the vertical antennas A1, A2, and A3, and phase comparison between the output signal of the amplification section A4 and the output signal of the amplification section A5. A phase comparison unit C1 for converting a phase difference of 180 ° (± π radian) into a voltage of ± eV, and a phase of an output signal of the amplification unit A4 and a phase of an output signal of the amplification unit A6 are compared to be ± 180 °.
A phase comparison unit C2 for converting a phase difference of (± π radians) into a voltage of ± eV; low-pass filters F1 and F2 for averaging output signals of the phase comparison units C1 and C2 to remove high-frequency noise such as spike noise; A / D converter A for converting the output signal of low-pass filter F1 to digital code Ax
7, a voltage comparison unit A8 for obtaining the sign of the output signal of the low-pass filter F2, and an azimuth calculation unit P2 for calculating the azimuth αa of the aircraft from the digital code Ax and the sign.

In the embodiment of the present invention, a response radio wave (frequency: 1090 MHz) of the secondary surveillance radar (SSR) is detected as a radio wave emitted by the aircraft detected by the radio wave direction identification device 2.
z) is used. However, the radio wave emitted by the aircraft is SS
It is not limited to the response radio wave of R.

As shown in FIG. 5, the three vertical antennas (omnidirectional in a horizontal plane) A1, A2, and A3 are orthogonal to a straight line connecting the antennas A1 and A2 and a straight line connecting the antennas A1 and A3. It is arranged to be. The distance between the antenna A1 and the antenna A2 and the distance between the antenna A1 and the antenna A3 are each 13.8 cm (（wavelength of the SSR response frequency of 1090 MHz). Furthermore,
When the azimuth is detected in an absolute direction, the antenna A
The direction connecting the antenna 1 to the antenna A2 or the direction connecting the antenna A1 to the antenna A3 may be adjusted to any one of north, south, east and west.

For example, assuming that the direction connecting antennas A1 and A2 is 0 ° and the direction connecting antennas A1 and A3 is 90 °, the azimuth angle of the aircraft that is the source of radio waves captured by antennas A1, A2 and A3 αa is obtained by the azimuth angle calculation unit P2 as follows.

When the sign of the voltage comparison unit A8 is positive, α
a = cos ^-1 (Ax) [radian].

When the sign of the voltage comparison unit A8 is negative, α
a = 2π-cos ^-1 (Ax) [radian].

The operation of the aircraft flight position detecting device according to claim 1 configured as described above will be described. For sound and radio waves emitted by a flying aircraft, an azimuth αm at which a time-varying sound arrives is determined by a sound wave type azimuth and elevation angle identification device 1.
And the azimuth αa at which the time-varying radio wave arrives is detected by the radio wave direction identification device 2.

Next, as shown in FIG. 6, the time-varying azimuth αm and the time-varying azimuth αa detected by the discriminating devices 1 and 2 are input to the time difference detecting unit 3. Then, in the time difference detection unit 3, the azimuth α due to the sound wave
The time difference td between m and the azimuth αa by radio waves is calculated. When the time difference td continues to be the same value for a predetermined time or more, the determination unit 4 determines that the sound source and the radio wave source are the same, that is, the sound is measured by the sound wave azimuth and elevation angle identification device 1 and the sound is aircraft noise. I do.

Then, the flight position calculation unit 5 calculates the distance L between the observation point and the aircraft by multiplying the time difference td by the speed of sound, and calculates the position of the aircraft from the azimuth αm and the elevation βm based on the sound.

As described above, it is assumed that the aircraft noise is identified by comparing the temporal change of the azimuth αm at which the sound emitted from the flying aircraft arrives with the temporal change of the azimuth αa at which the SSR radio wave arrives. , The distance L between the observation point and the aircraft calculated by multiplying the time difference td between the azimuth αm by the sound wave and the azimuth αa by the radio wave by the speed of sound, and the azimuth αm by the sound
And the elevation angle βm, the position of the aircraft can be specified. Further, by connecting the distance L between the observation point and the aircraft, which changes every moment, the azimuth angle αm and the elevation angle βm of the aircraft, the route of the aircraft can be obtained.

As shown in FIG. 7, the aircraft flight position detecting device according to the second aspect includes a sound wave type azimuth discriminating device 6 which detects a sound emitted from the aircraft and outputs an azimuth signal αm corresponding to the azimuth of the aircraft. A radio wave type azimuth and elevation identification device 7 for detecting radio waves emitted by an aircraft and outputting an azimuth signal αa according to the azimuth of the aircraft and an elevation signal βa according to the elevation of the aircraft 7
A time difference detector 8 for outputting a time difference td between the azimuth signal αm from the sound wave type azimuth discriminating device 6 and the azimuth signal αa from the radio wave azimuth and elevation angle discriminating device 7;
If the same value continues for a predetermined time or more, the determination unit 9 determines that the sound source and the radio wave source are the same, calculates the distance L between the observation point and the aircraft by multiplying the time difference td by the sound speed, and calculates the azimuth by the radio wave. A flight position calculation unit 10 for calculating the position of the aircraft from the angle signal αa and the elevation signal βa.

The aircraft flight position detecting device according to the second aspect of the present invention is the aircraft flight position detecting device shown in FIG. 1, in which three microphones are used instead of the sound wave type azimuth and elevation angle discriminating device 1, and the sound emitted by the aircraft is used. Azimuth identification device 6 for detecting the azimuth αm of the aircraft by detecting the azimuth angle αm of the aircraft, using four antennas instead of the radio wave azimuth identification device 2 to detect the radio waves emitted by the aircraft and to determine the azimuth αa of the aircraft The configuration is the same as that of the aircraft flight position detecting device of claim 1 except that a radio wave type azimuth and elevation angle discriminating device 7 for obtaining the elevation angle βa is provided.

The method of calculating the azimuth αm by the sound wave type azimuth discriminating device 6 and the method of calculating the azimuth αa and the angle of elevation βa by the radio wave type azimuth and elevation angle discriminating device 7 are described below. 1 or radio wave type azimuth identification device 2
Since the calculation is performed in accordance with the calculation method according to, the description is omitted.

As shown in FIG. 8, the aircraft flight position detecting device according to the third aspect detects a sound emitted from the aircraft and generates an azimuth signal αm corresponding to the azimuth of the aircraft and an elevation signal βm corresponding to the elevation of the aircraft. Output sound wave type azimuth and elevation angle identification device 1
1 and a radio wave type azimuth discriminating apparatus 1 which detects a radio wave emitted from an aircraft and outputs an azimuth signal αa corresponding to the azimuth of the aircraft.
2, a cross-correlation function calculator 1 for calculating a cross-correlation function between the azimuth signal αm from the sound wave type azimuth and elevation angle discrimination device 11 and the azimuth signal αa from the radio wave type azimuth angle discrimination device 12.
3, when the maximum value of the cross-correlation function is equal to or more than a predetermined value at the same position, a determination unit 14 that determines that the sound source and the radio wave source are the same, and the azimuth of the radio wave that gives the maximum value of the cross-correlation function A flight position calculation unit that calculates the distance L between the observation point and the aircraft by multiplying the delay time of the sound azimuth signal αm with respect to the signal αa by the speed of sound, and calculates the position of the aircraft from the sound azimuth signal αm and the elevation signal βm. 15

The sound wave type azimuth and elevation angle discriminating device 11
And the radio wave type azimuth discriminating device 12 is a sound wave type azimuth and elevation discriminating device 1 in the aircraft flight position detecting device according to claim 1.
Since the configuration is the same as that of the radio wave type azimuth discriminating apparatus 2, the description is omitted.

The operation of the above-configured aircraft flight position detecting device according to claim 3 will be described. The cross-correlation function calculation unit 13 determines the azimuth αm of the sound wave detected by the sound wave type azimuth and elevation angle discrimination device 11 and the azimuth αa of the radio wave detected by the radio wave type azimuth discrimination device 12 to determine the mutual relationship between the time-series data. Calculate the correlation function.

As shown in FIG. 6, the azimuth αm at which the sound arrives is delayed by a certain time with respect to the azimuth αa at which the radio wave arrives, and changes substantially similarly. However, since any measurement data (azimuths αm, αa) actually contains errors and noises, it is not easy to obtain the correlation between the measurement data as it is. Therefore, if a cross-correlation function is obtained by applying a statistical method to the measurement data, in the case of an event accompanying the passage of an aircraft, a large correlation value is shown for each change, and errors and noise are removed because there is no correlation. Will be.

Next, the judgment section 14 compares the maximum value of the cross-correlation function calculated by the cross-correlation function operation section 13 with a preset threshold value, and determines that the maximum value of the cross-correlation function is equal to or larger than the threshold value. If there is, the sound source and the radio wave source are the same, that is, it is determined that the sound measured by the sound wave direction identification device 5 is the aircraft noise.

Further, the flight position calculator 15 calculates the delay time of the azimuth αm with respect to the azimuth αa giving the maximum value of the cross-correlation function calculated by the cross-correlation function calculator 13.
Therefore, the distance L between the observation point and the aircraft is calculated by multiplying the time difference by the speed of sound, and the position of the aircraft is calculated from the azimuth αm and the elevation angle βm based on the sound.

Thus, the azimuth αm at which the sound from the flying aircraft arrives and the azimuth α at which the SSR radio wave arrives
The distance L between the observation point and the aircraft calculated by multiplying the time difference between the azimuth angle αm by the sound wave and the azimuth angle αa by the radio wave by the speed of sound, assuming the maximum value of the cross-correlation function of a and the aircraft noise identification, The position of the aircraft can be specified from the azimuth angle αm and the elevation angle βm based on the sound. In addition, the distance L between the observation point and the aircraft, which changes every moment, the azimuth αm of the aircraft
And the elevation angle βm, the route of the aircraft can be determined.

According to a fourth aspect of the present invention, there is provided an aircraft flight position detecting device as shown in FIG. 8, wherein three microphones are used in place of the sound wave type azimuth and elevation angle discriminating device 11 to detect sound emitted from the aircraft. The aircraft's azimuth αm
Is provided, and instead of the radio wave azimuth identification device 12, four antennas are used to detect radio waves emitted by the aircraft to obtain the azimuth αa and the elevation angle βa of the aircraft. Except for the elevation identification device,
The configuration is the same as that of the aircraft flight position detecting device of the third aspect. Therefore, description is omitted.

The sound wave type azimuth discriminating device and the radio wave type azimuth and elevation angle discriminating device in the aircraft flight position detecting device according to the fourth aspect of the present invention are the sound wave type azimuth discriminating device 6 shown in FIG. The configuration is the same as that of the elevation angle identification device 7.
Therefore, description is omitted.

As shown in FIG. 9, the aircraft flight position detecting device detects a sound emitted from the aircraft and generates an azimuth signal αm corresponding to the azimuth of the aircraft and an elevation signal βm corresponding to the elevation of the aircraft. Output sound wave type azimuth and elevation angle identification device 1
6 and a radio wave type azimuth discriminating apparatus 1 which detects radio waves emitted from an aircraft and outputs an azimuth signal αa corresponding to the azimuth of the aircraft.
7 and the azimuth signal αm from the sound wave type azimuth and elevation angle discriminating device 16 and the azimuth signal αa from the radio wave type azimuth discriminating device 17 are treated as a two-dimensional line drawing of time and azimuth angle. A pattern matching device 18 for evaluating the degree by pattern matching, and an observation point obtained by multiplying the delay time of the sound azimuth signal αm with respect to the radio wave azimuth signal αa giving the maximum value of the cross-correlation function by the pattern matching device 18 by the speed of sound. And a flight position calculation unit 19 that calculates the distance L between the aircraft and the aircraft and calculates the position of the aircraft from the azimuth signal αm and the elevation signal βm based on sound.

The sound wave type azimuth and elevation angle discrimination device 16
And the radio wave type azimuth discriminating device 17 is a sound wave type azimuth and elevation discriminating device 1 in the aircraft flight position detecting device according to claim 1.
Since the configuration is the same as that of the radio wave type azimuth discriminating apparatus 2, the description is omitted.

The pattern matching device 18 includes a pixelizing section 20, a cross-correlation function calculating section 21, and a determining section 22. The operation of the aircraft flight position detecting device according to claim 5 configured as described above will be described. Pixelization unit 2
0 records the azimuth αm measured by the sound wave azimuth and elevation angle identification device 16 and the azimuth αa measured by the radio wave azimuth identification device 17 together with time information as shown in FIG. For example, the recording time interval is every second,
As shown in FIG. 10 and FIG. 11, one of the 180 storage areas provided at every 2 ° (π / 90 radians) corresponds to the measured azimuth αm, αa. (A black part in the figure) and other areas are recorded as “0” (a white part in the figure). 10 and 11, the interval between the vertical lines corresponds to 1 second, and the interval between the horizontal lines corresponds to an azimuth angle of 2 ° (π / 90 radians).

As described above, 180 provided at every azimuth angle of 2 °
Pixelization means that any one of the storage areas is set to “1” as a representative, the other area is set to “0”, and the measured azimuths αm and αa are binarized and recorded. 8 corresponds to processing a continuous curve of the azimuth angle αm and the azimuth angle αa into a discontinuous waveform as shown in FIGS. 10 and 11.

Next, the cross-correlation function calculator 21 performs the processing shown in FIG.
The pixelized azimuth angle is obtained in order to obtain information on whether or not the discontinuous waveform of the pixelized azimuth angle αm shown in FIG. 11 matches the discontinuous waveform of the pixelated azimuth angle αa shown in FIG. Cross-correlation function φx between αm and azimuth αa
Calculate y (△ t). The cross-correlation is calculated by shifting one time axis (azimuth angle αm) shown in FIG. 10 with respect to the other time axis (azimuth angle αa) shown in FIG. Ask for.

Next, when the value of the correlation obtained by the cross-correlation function calculator 21 is larger than a preset threshold value, the judgment unit 22 judges that the sound source and the radio wave source are the same.
The value of the correlation obtained by the cross-correlation function calculation unit 21 means the similarity of the change in the numerical value of different populations. When comparing radio waves and sound waves, the change in the azimuth αa at which the radio waves arrive is observed earlier, since radio waves propagate overwhelmingly faster,
The azimuth αm at which the sound arrives changes so as to follow.

In the case of the azimuth αm and the azimuth αa shown in FIGS. 10 and 11, when the time axis of the sound azimuth αm is shifted so as to advance 2 seconds, the maximum value of the correlation is “1”. Therefore, the threshold value set in the determination unit 22 is set to, for example, 0.
If it is set to 8, the sound source and the radio wave source are the same, that is, measured by the sound wave type azimuth and elevation angle discrimination device 16, and the sound is determined to be aircraft noise.

The sound wave type azimuth and elevation angle discriminating device 16
When the waveform as shown in FIG. 12 is obtained as the azimuth angle of the sound measured by the following formula, the maximum value of the correlation with the azimuth angle αa shown in FIG. If the threshold value is set to, for example, 0.8, the sound source and the radio wave source are not the same, and the sound wave type azimuth angle and elevation angle identification device 1
6, the sound is not determined to be aircraft noise.

The output signals of the sound wave type azimuth / elevation angle discriminating device 16 and the radio wave type azimuth angle discriminating device 17 are converted into time and azimuth angle α.
m and αa are treated as two-dimensional line drawings, and the similarity between these two types of line drawings is evaluated by pattern matching for calculating the two-dimensional cross-correlation and obtaining the maximum correlation value. The cancellation and the delay time can be clearly measured, and it is easy to determine whether the noise is caused by an aircraft. In particular, when the azimuths αm and αa change slowly, the correlation function also changes slowly, and it is difficult to grasp features from the correlation function, so pattern matching is effective.

Further, the flight position calculation unit 19 determines the distance L between the observation point and the aircraft by multiplying the time difference between the azimuth angle αm by the sound wave and the azimuth angle αa by the radio wave by the sound speed, and also obtains the azimuth angle αm by sound and the elevation angle βm. From the position of the aircraft.

As described above, the time difference between the azimuth angle αm due to the sound wave and the azimuth angle αa due to the radio wave is multiplied by the sound speed on the assumption that the aircraft noise is identified by pattern matching between the azimuth angle signal αm of the sound and the azimuth angle signal αa of the radio wave. L, the azimuth angle αm and the elevation angle β due to the sound
The position of the aircraft can be specified from m. Further, by connecting the distance L between the observation point and the aircraft, which changes every moment, the azimuth angle αm and the elevation angle βm of the aircraft, the route of the aircraft can be obtained.

According to a sixth aspect of the present invention, there is provided an aircraft flight position detecting apparatus as shown in FIG. 9, wherein three microphones are used in place of the sound wave type azimuth and elevation angle discriminating apparatus 16 to detect sounds emitted by the aircraft. The aircraft's azimuth αm
Is provided, and instead of the radio wave azimuth identification device 17, four antennas are used to detect radio waves emitted by the aircraft to obtain the azimuth αa and the elevation βa of the aircraft. Except for the elevation identification device,
The configuration is the same as that of the aircraft flight position detecting device according to claim 5. Therefore, description is omitted.

The sound wave type azimuth discriminating device and the radio wave type azimuth and elevation angle discriminating device in the aircraft flight position detecting device according to the present invention are the sound wave type azimuth discriminating device 6 shown in FIG. The configuration is the same as that of the elevation angle identification device 7.
Therefore, description is omitted.

[0058]

As described above, according to the first or second aspect of the present invention, the temporal change of the azimuth at which the sound emitted by the flying aircraft arrives and the azimuth at which the radio wave emitted by the aircraft arrives By comparing the change over time, it is easy to identify whether the noise is caused by the aircraft, and furthermore, the distance between the observation point and the aircraft calculated by multiplying the time difference between the azimuth angle by the sound wave and the azimuth angle by the radio wave by the sound speed, The position of the aircraft can be specified from the azimuth and elevation angle of the sound.

According to the third or fourth aspect of the present invention, the azimuth angle at which the measured sound arrives and the azimuth angle at which the radio wave arrives are subjected to a statistical method to determine the correlation therebetween. If this is the case, a large correlation value is shown for each change, errors and noise are removed because they are uncorrelated, and a stable identification result of whether or not the noise is caused by an aircraft is obtained. The position of the aircraft can be specified from the distance between the aircraft and the observation point calculated by multiplying the time difference of the angle by the speed of sound, and the azimuth and elevation angle of the sound.

According to the fifth or sixth aspect of the present invention, the measured azimuth at which the sound arrives and the azimuth at which the radio wave arrives are treated as two-dimensional line drawings, and the similarity between the two types of line drawings is subjected to pattern matching. Calculates the two-dimensional cross-correlation to determine the maximum correlation value, so that by calculating the two-dimensional cross-correlation, errors and noise cancel each other out, and it is stabilized whether the noise is caused by aircraft. The identification result is obtained, and the aircraft position can be specified from the distance between the observation point and the aircraft calculated by multiplying the time difference between the azimuth angle by the sound wave and the azimuth angle by the radio wave by the speed of sound, and the azimuth and elevation angle by the sound. .

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an aircraft flight position detection device according to the invention of claim 1;

FIG. 2 is a configuration diagram of a sound wave type azimuth and elevation angle discrimination device.

FIG. 3 is an explanatory diagram showing an arrangement of microphones.

FIG. 4 is a configuration diagram of a radio wave direction identification device.

FIG. 5 is an explanatory diagram showing the arrangement of antennas.

FIG. 6 is a diagram showing a difference in change in azimuth angle between radio waves and sound.

FIG. 7 is a configuration diagram of an aircraft flight position detection device according to the invention of claim 2;

FIG. 8 is a configuration diagram of an aircraft flight position detection device according to the invention of claim 3;

FIG. 9 is a configuration diagram of an aircraft flight position detection device according to the invention of claim 5;

FIG. 10 is a diagram in which the azimuth angle at which sound arrives is pixelated.

FIG. 11 is a diagram in which the azimuth angle at which a radio wave arrives is pixelated.

FIG. 12 is a diagram in which the azimuth angle at which a certain sound arrives is pixelated.

[Explanation of symbols]

1, 11, 16 ... sound wave type azimuth and elevation angle identification device, 2,
12, 17 ... radio wave direction identification device, 3, 8 ... time difference detection unit, 4, 9, 14, 22 ... determination unit, 5, 10, 15, 1
9: Flight position calculation unit, 6: Sound wave type azimuth identification device, 7 ...
Radio wave type azimuth and elevation angle discriminating device, 13, 21: Cross-correlation function calculating unit, 18: Pattern matching device, 20: Pixel forming unit, A1, A2, A3: Vertical antenna, M1,
M2, M3, M4 ... microphones.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Koichi Makino 3-20-41 Higashimoto-cho, Kokubunji-shi, Tokyo Inside the Kobayashi Science Research Institute

Claims (6)

[Claims] 1. A sound wave type azimuth and elevation discriminating means for detecting a sound emitted from an aircraft and outputting an azimuth signal corresponding to the azimuth of the aircraft and an elevation signal according to the elevation of the aircraft, and detecting a radio wave emitted by the aircraft. Radio azimuth identification means for outputting an azimuth signal corresponding to the azimuth of the aircraft, and a time difference between an azimuth signal by the acoustic azimuth and elevation identification means and an azimuth signal by the radio azimuth identification means. A time difference detecting means for outputting a sound source and a radio wave source when the time difference continues the same value for a predetermined time or more, and a determining means for determining that the sound source and the radio wave source are the same. An aircraft flight position detecting device comprising: a flight position calculating means for calculating a distance and calculating a position of the aircraft from the azimuth signal and the elevation signal by sound. 2. A sound wave type azimuth discriminating means for detecting a sound emitted from an aircraft and outputting an azimuth signal corresponding to the direction of the aircraft, and an azimuth signal corresponding to the direction of the aircraft by detecting radio waves emitted from the aircraft. Radio azimuth and elevation discriminating means for outputting an elevation signal according to the elevation angle of the aircraft, and a time difference between the azimuth signal from the acoustic azimuth discrimination means and the azimuth signal from the radio azimuth and elevation discrimination means. A time difference detecting means for outputting a sound source and a radio wave source when the time difference continues the same value for a predetermined time or more, and a determining means for determining that the sound source and the radio wave source are the same. An aircraft flight position detecting device comprising: a flight position calculating means for calculating a distance and calculating a position of the aircraft from the azimuth signal and the elevation signal by radio waves. 3. A sound wave type azimuth and elevation discriminating means for detecting a sound emitted from an aircraft and outputting an azimuth signal corresponding to the azimuth of the aircraft and an elevation signal according to the elevation of the aircraft, and detecting a radio wave emitted by the aircraft. Azimuth discriminating means for outputting an azimuth signal corresponding to the azimuth of the aircraft, and interchanging azimuth signals by the acoustic azimuth and elevation discriminating means and azimuth signals by the radio azimuth discriminating means. Cross-correlation function calculating means for calculating a correlation function; determining means for determining that a sound source and a radio wave source are the same when the maximum value of the cross-correlation function has a predetermined value or more at the same position; The distance between the observation point and the aircraft is calculated by multiplying the delay time of the azimuth signal of the sound with respect to the azimuth signal of the radio wave giving the maximum value of the function by the speed of sound, and the position of the aircraft is calculated from the azimuth signal and the elevation signal by sound. Performance An aircraft flight position detecting device comprising a flight position calculating means for calculating the flight position. 4. A sound wave type azimuth identification means for detecting a sound emitted from an aircraft and outputting an azimuth signal corresponding to the azimuth of the aircraft, and an azimuth signal corresponding to the azimuth of the aircraft by detecting a radio wave emitted from the aircraft. Radio wave type azimuth and elevation angle discriminating means for outputting an elevation signal corresponding to the elevation angle of the aircraft, and the interaction between the azimuth signal by the sound wave type azimuth angle discrimination means and the azimuth signal by the radio wave type azimuth angle and elevation angle discrimination means. Cross-correlation function calculating means for calculating a correlation function; determining means for determining that a sound source and a radio wave source are the same when the maximum value of the cross-correlation function has a predetermined value or more at the same position; The distance between the observation point and the aircraft is calculated by multiplying the delay time of the sound azimuth signal with respect to the azimuth signal of the radio wave giving the maximum value of the function by the speed of sound, and the position of the aircraft is calculated from the azimuth signal and the elevation signal by radio waves. An aircraft flight position detection device comprising a flight position calculation means for calculating. 5. A sound wave type azimuth and elevation discriminating means for detecting a sound emitted from an aircraft and outputting an azimuth signal corresponding to the azimuth of the aircraft and an elevation signal according to the elevation of the aircraft, and detecting a radio wave emitted by the aircraft. Radio azimuth identification means for outputting an azimuth signal in accordance with the azimuth of the aircraft, and an azimuth signal by the acoustic azimuth and elevation identification means and an azimuth signal by the radio azimuth identification means. A pattern matching unit that treats the azimuth as a two-dimensional line drawing and evaluates the similarity between the two types of line drawing by pattern matching, and a sound corresponding to an azimuth signal of a radio wave that gives the maximum value of the cross-correlation function by the pattern matching unit. The delay time of the azimuth signal is multiplied by the speed of sound to calculate the distance between the observation point and the aircraft, and the position of the aircraft is calculated from the azimuth signal and the elevation signal by sound. An aircraft flight position detection device comprising flight position calculation means. 6. A sound wave type azimuth discriminating means for detecting a sound emitted from an aircraft and outputting an azimuth signal corresponding to the azimuth of the aircraft, and an azimuth signal corresponding to the azimuth of the aircraft by detecting a radio wave emitted from the aircraft. A radio azimuth and elevation identification means for outputting an elevation signal according to the elevation of the aircraft, and an azimuth signal by the acoustic azimuth identification means and an azimuth signal by the radio azimuth and elevation identification means. A pattern matching unit that treats the azimuth as a two-dimensional line drawing and evaluates the similarity between the two types of line drawing by pattern matching, and a sound corresponding to an azimuth signal of a radio wave that gives the maximum value of the cross-correlation function by the pattern matching unit. The delay time of the azimuth signal is multiplied by the speed of sound to calculate the distance between the observation point and the aircraft, and the position of the aircraft is calculated from the azimuth signal and the elevation signal by radio waves. An aircraft flight position detecting device, comprising: a flight position calculating means.