JP6880605B2 - Target existence likelihood calculation device and target existence likelihood calculation method - Google Patents

Description

The present invention relates to a target existence likelihood calculation device and a target existence likelihood calculation method for calculating the likelihood with respect to an approximate distance and an approximate depth of a target object.

The sonar device detects the presence of a target by, for example, being mounted on a ship and receiving sound waves radiated from the target or sound waves transmitted from the sonar and echoed by the target propagating in the ocean. It is a thing. In a conventional sonar device, when a signal radiated from a target is received, it is described in, for example, Non-Patent Document 1 based on the time change of the frequency of the received signal, the time change of the received direction, the identification information by listening sound, and the like. By performing such target motion analysis, the course from the ship equipped with the sonar device to the target and the speed of the target are estimated.

V.J.AIDALA, S.E.HAMMEL "Utilization of Modified Polar Coordinates for Bearing-Only Tracking" IEEE Trans. Automat. Contr., Vol.AC-28, pp.283-294, Mar. 1983

By the way, when the signal radiated from the target is received, it is judged whether or not the collision avoidance action to avoid the collision between the target and the own ship is necessary in operation, and there is a risk of attack from the target. Need to be judged. Therefore, it is required to output the distance from the own ship to the target immediately after receiving the signal from the target.

However, in the target motion analysis described in Non-Patent Document 1, it takes time to converge the solution when calculating the distance from the own ship to the target, the course of the target, and the speed of the target. Therefore, there is a problem that it takes time to determine whether or not the above-mentioned collision avoidance action is necessary and whether or not there is a danger.

Therefore, a target existence likelihood calculation device and a target existence likelihood calculation method that can quickly determine the distance from the own ship to the target object are desired.

The target existence probability calculation device according to the present invention is mounted on a sonar device that estimates the distance to the target, and calculates the target existence probability that indicates the likelihood of the position where the target exists. Environmental information indicating the environmental state around the sonar device, own ship information indicating the state of the ship on which the sonar device is mounted, actual measurement reception level of a signal radiated from the target, and the above. The first input unit into which the target information obtained from the target object and the frequency information of the signal are input, the environmental information input to the first input unit, the own ship information, the actual measurement reception level, and the above. A first likelihood calculation unit for calculating a first target existence probability based on the target information and the frequency information is provided, and the first likelihood calculation unit includes the environment information, the own ship information, and the frequency. A propagation loss calculator that calculates the propagation loss at a preset target depth based on the information, and a prediction of the signal emitted from the target based on the target information from the target and the calculated propagation loss. The first target existence probability is calculated based on the predicted reception level calculator that calculates the predicted reception level indicating the value, the actually measured reception level from the target object, and the calculated predicted reception level. the first and the target presence likelihood calculating device and a target presence likelihood calculator, before and Kiwa border information, before Symbol own ship information, an arrival Fu elevation of the signal emitted from said target is input a second input unit that, the said environment information input to the second input section, based on the Time information and the incoming Fu elevation, second likelihood calculator for calculating a second target exists likelihood The second likelihood calculation unit is calculated as a sound line calculator that calculates the sound line depth at a preset target depth based on the environmental information, the own ship information, and the arrival elevation angle. was based on the sound ray depth, the second and the target presence likelihood calculating device and a second target exists likelihood calculator for calculating a second target exists likelihood, the first target exists likelihood It is provided with an integrator that integrates the first target existence probability calculated by the calculation device and the second target existence probability calculated by the second target existence probability calculation device. ..

As described above, according to the present invention, the distance from the own ship to the target can be quickly determined by calculating the target existence likelihood using the information about the signal received from the target.

It is a block diagram which shows an example of the structure of the target existence likelihood calculation apparatus which concerns on Embodiment 1. FIG. It is the schematic which shows an example of the distance characteristic of the propagation loss calculated by the propagation loss calculator of FIG. It is a schematic diagram which shows an example of the predicted reception level calculated by the predicted reception level calculator of FIG. It is a schematic diagram which shows an example of the target existence likelihood calculated by the target existence likelihood calculator of FIG. It is a schematic diagram which shows an example of the calculation result at the time of calculating the target existence likelihood with respect to a plurality of target depths in the target existence likelihood calculator of FIG. It is a block diagram which shows an example of the structure of the target existence likelihood calculation apparatus which concerns on Embodiment 2. FIG. It is a schematic diagram which shows an example of the target existence likelihood calculated by the target existence likelihood calculator of FIG. It is a schematic diagram which shows an example of the calculation result at the time of calculating the target existence likelihood with respect to a plurality of target depths in the target existence likelihood calculator of FIG. It is a block diagram which shows an example of the structure of the target existence likelihood calculation apparatus which concerns on Embodiment 3. FIG. It is the schematic for demonstrating the integration process performed by the multiplier of FIG.

Hereinafter, embodiments of the present invention will be described. The target existence likelihood calculation device according to the embodiment of the present invention is provided in, for example, a sonar device mounted on a ship for estimating the distance and depth to a target. The target existence probability calculation device is based on the surrounding environmental conditions, the state of the own ship on which the sonar device is mounted, and information on the signal received from the target, from the own ship to the target existing on the ocean or in the ocean. The target existence likelihood, which indicates the likelihood of the position where the target exists, such as the approximate distance of the target and the approximate depth of the target, is calculated.

Embodiment 1.
First, the target existence likelihood calculation device according to the first embodiment of the present invention will be described. In this target existence probability calculation device, as information about the signal received from the target, the actual measurement reception level of the signal radiated from the target, the target information such as the radiation noise obtained from the target, and the target information radiated from the target. The frequency information of the signal is used.

[Configuration of target existence likelihood calculation device]
FIG. 1 is a block diagram showing an example of the configuration of the target existence likelihood calculation device 10 according to the first embodiment. As shown in FIG. 1, the target existence likelihood calculation device 10 includes a propagation loss calculator 11 as a likelihood calculation unit, a predicted reception level calculator 12, a target existence likelihood calculator 13, and an input terminal as an input unit. It includes 1a to 1e and an output terminal 2a as an output unit.

The input terminal 1a has a BT (BARHY-THERMOGRAPHY) profile, which is characteristic data showing the relationship of water temperature with respect to the water depth, and an environment showing the environmental state around the ship such as the seafloor topography, bottom sediment, wind speed, or sea state of the target direction with respect to the ship. Information is entered. Information indicating the state of the ship, such as sensor specifications such as the depth of the ship or the beam pattern, is input to the input terminal 1b. Target information indicating various information such as radiation noise obtained from the target object is input to the input terminal 1c. The actual measurement reception level of the signal radiated from the target is input to the input terminal 1d. The frequency information of the signal radiated from the target is input to the input terminal 1e. In the following description, "the sound source level such as radiation noise from the target object" will be referred to as "target information".

In the propagation loss calculator 11, the input terminals 1a, 1b and 1e are connected to the input side, and the predicted reception level calculator 12 is connected to the output side. The propagation loss calculator 11 is based on the environmental information input to the input terminal 1a, the own ship information input to the input terminal 1b, and the frequency information of the signal radiated from the target input to the input terminal 1e. The distance characteristics of the propagation loss are calculated using the sound propagation model. The propagation loss calculator 11 outputs the calculated propagation loss to the predicted reception level calculator 12.

In the predicted reception level calculator 12, the input terminal 1c and the propagation loss calculator 11 are connected to the input side, and the target existence likelihood calculator 13 is connected to the output side. The predicted reception level calculator 12 determines the predicted reception level indicating the predicted value of the signal radiated from the target based on the target information input to the input terminal 1c and the propagation loss input from the propagation loss calculator 11. calculate. The predicted reception level calculator 12 outputs the calculated predicted reception level to the target existence likelihood calculator 13.

The target existence likelihood calculator 13 has an input terminal 1d and a predicted reception level calculator 12 connected to the input side, and an output terminal 2a connected to the output side. The target existence likelihood calculator 13 is based on the actual measurement reception level of the signal radiated from the target object input to the input terminal 1d and the predicted reception level input from the predicted reception level calculator 12, and the target existence likelihood calculator 13. Calculate the distance characteristics of. The target existence likelihood calculator 13 outputs the calculated target existence likelihood calculator from the output terminal 2a.

The target existence likelihood output from the output terminal 2a is displayed by, for example, a display unit (not shown) provided as a part of the output unit. The display unit visually displays the target existence likelihood calculated by the target existence likelihood calculator 13 by a graph, a map, or the like. The display of the target existence likelihood is not limited to this example, and may be performed by, for example, a display unit provided in the sonar device equipped with the target existence likelihood calculation device 100.

[Calculation method of target existence likelihood]
Next, a method of calculating the target existence likelihood in the target existence likelihood calculation device 10 according to the first embodiment will be described. When environmental information, own ship information, target information, and actual measurement reception level from the target object are input to the target existence probability calculation device 10, the target existence probability calculation device 10 uses the input information. , Calculate the target existence likelihood.

(Calculation of propagation loss)
First, the target existence likelihood calculation device 10 calculates the distance characteristic of the propagation loss by the propagation loss calculator 11. The propagation loss calculator 11 propagates sound waves based on the environmental information input to the input terminal 1a, the own ship information input to the input terminal 1b, and the frequency information of the signal from the target input to the input terminal 1e. using the model, the distance properties of the propagation loss in the preset target depth z _t (hereinafter, appropriately referred to as a "transmission loss") is calculated TL (r).

The sound wave propagation model used at this time is, for example, the document "Michael D. Collins," A split-step Pade solution for the parabolic equation method "J. Acoust. Soc. Am. 93 (4), Pt. 1, 1993. A sound wave propagation model based on the wave theory as described in the above may be used. Also, not limited to this, for example, the literature "Henry Weinberg and Ruth Eta Keenan," Gaussian ray bundles for modeling high-frequency propagation loss under shallow-water conditions, "J. Acoust. Soc. Am. 100 (3), 1996. A sound wave propagation model based on the sound ray theory as described in "." May be used. Further, for example, an approximate calculation assuming spherical diffusion or cylindrical diffusion may be used.

FIG. 2 is a schematic view showing an example of the distance characteristic of the propagation loss calculated by the propagation loss calculator 11 of FIG. In FIG. 2, the horizontal axis represents the distance r from the own ship to the target, and the vertical axis represents the propagation loss TL (r). By calculating the propagation loss as described above, as shown in FIG. 2, the propagation loss TL (r) corresponding to the distance r from the own ship to the target is calculated.

(Calculation of predicted reception level)
Next, the target existence likelihood calculation device 10 calculates the predicted reception level by the predicted reception level calculator 12. The predicted reception level calculator 12 uses the equation (1) based on the target information SL input to the input terminal 1c and the propagation loss TL (r) input from the propagation loss calculator 11, and the predicted reception level RL. _{Calculate p} (r).

FIG. 3 is a schematic view showing an example of the predicted reception level calculated by the predicted reception level calculator 12 of FIG. In FIG. 3, the horizontal axis represents the distance r from the own ship to the target, and the vertical axis represents the predicted reception level RL _p (r). By calculating the predicted reception level as described above, as shown in FIG. 3, the predicted reception level RL _p (r) corresponding to the distance r from the own ship to the target is calculated.

(Calculation of target existence likelihood)
Next, the target existence likelihood calculation device 10 calculates the distance characteristic of the target existence likelihood by the target existence likelihood calculator 13. The target existence likelihood calculator 13 uses the equation (2) based on the actually measured reception level RL input to the input terminal 1d and the predicted reception level RL _{p (r) input from the predicted reception level calculator 12.} The distance characteristic of the target existence likelihood (hereinafter, appropriately referred to as “target existence likelihood”) p _RL (r | RL) is calculated. In the equation (2), the function f is a probability density function of a normal distribution having an expected value μ and a standard deviation σ, as shown in the equation (3).

In equation (2), “σ _r ” is the standard deviation that depends on the measured reception level RL and the predicted reception level RL _{p (r).} If the standard deviation σ _r is known, it is calculated by the square root of the sum of squares. On the other hand, when the standard deviation σ _r is unknown, it is a fixed value obtained empirically.

FIG. 4 is a schematic view showing an example of the target existence likelihood calculated by the target existence likelihood calculator 13 of FIG. In FIG. 4, the horizontal axis represents the distance r from the own ship to the target, and the vertical axis represents the target existence likelihood p _RL (r | RL). By calculating the target existence likelihood as described above, as shown in FIG. 4, the target existence likelihood p _RL (r | RL) corresponding to the distance r from the own ship to the target object is calculated. Then, in the first embodiment, it is determined that the target exists at the position of the distance from the own ship where the value of _{the target existence likelihood p RL (r | RL) thus obtained is the highest.} be able to.

The target existence likelihood calculator 13 _{can perform a calculation using the equation (2) for a plurality of target depths z t_n} (n = 1, 2, ..., N). By calculating multiple target existence likelihoods corresponding to a plurality of target depths z _{t_n and displaying the calculated multiple target existence likelihoods p RL} (r | RL) on a color map, from the own ship to the target object. It is possible to grasp the change in _{the target existence likelihood pRL} (r | RL) not only in the distance direction but also in the depth direction of the target object.

FIG. 5 is a schematic view showing an example of a calculation result when the target existence likelihood calculator 13 of FIG. 1 calculates the target existence likelihood for a plurality of target depths. 5, the horizontal axis represents the distance r from Time to the target, the vertical axis indicates the depth z _t of the target. The target existence likelihood p _RL (r | RL) is indicated by the color state on the color map. In the first embodiment, it is determined that the target exists at the position of the distance and the depth from the own ship where the value of _{the target existence likelihood p RL (r | RL) thus obtained is the highest.} be able to.

As described above, according to the first embodiment, the target exists by using the measured reception level of the signal radiated from the target as the information regarding the signal received from the target, the target information, and the frequency information of the signal. Since the likelihood is calculated, the distance from the ship to the target can be determined quickly. Further, by calculating the propagation loss at a plurality of target depths and calculating the target existence likelihood based on the calculated plurality of propagation losses, it is possible to grasp the distance direction and the depth direction from the own ship to the target object. Therefore, the position of the target from the own ship where the target exists can be estimated with higher accuracy.

Embodiment 2.
Next, Embodiment 2 of the present invention will be described. In the above-described first embodiment, the measured reception level and the target information of the signal radiated from the target object are used as the information regarding the signal received from the target object, but in the second embodiment, the signal received from the target object is used. The arrival elevation angle of the signal radiated from the target is used as information about. In the following description, the parts common to the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

[Configuration of target existence likelihood calculation device]
FIG. 6 is a block diagram showing an example of the configuration of the target existence likelihood calculation device 20 according to the second embodiment. As shown in FIG. 6, the target existence likelihood calculation device 20 includes a sound line calculator 21 and a target existence likelihood calculator 22 as a likelihood calculation unit, and input terminals 1a, 1b and 1f as input units. It is provided with an output terminal 2b as an output unit.

Environmental information is input to the input terminal 1a as in the first embodiment. The own ship information is input to the input terminal 1b as in the first embodiment. The arrival elevation angle of the signal radiated from the target is input to the input terminal 1f.

In the sound line calculator 21, the input terminals 1a, 1b and 1c are connected to the input side, and the target existence likelihood calculator 22 is connected to the output side. The sound line calculator 21 performs sound line calculation processing based on the environmental information input to the input terminal 1a, the own ship information input to the input terminal 1b, and the arrival elevation angle input to the input terminal 1f. Then, the sound line calculator 21 calculates the sound line depth with respect to the distance based on the sound line obtained by the sound line calculation process. The sound line calculator 21 outputs the calculated sound line depth to the target existence likelihood calculator 22.

In the target existence likelihood calculator 22, the sound line calculator 21 is connected to the input side, and the output terminal 2b is connected to the output side. The target existence likelihood calculator 22 calculates the distance characteristic of the target existence likelihood based on the sound line depth input from the sound line calculator 21. The target existence likelihood calculator 22 outputs the calculated target existence likelihood calculator from the output terminal 2b.

The target existence likelihood output from the output terminal 2b is visually displayed by a graph, a map, or the like on a display unit (not shown) provided as a part of the output unit, for example. The display of the target existence likelihood is not limited to this example, and may be performed by, for example, a display unit provided in the sonar device equipped with the target existence likelihood calculation device 100.

[Calculation method of target existence likelihood]
Next, a method of calculating the target existence likelihood in the target existence likelihood calculation device 20 according to the second embodiment will be described. When environmental information, own ship information, and the elevation angle of arrival from the target are input to the target existence likelihood calculation device 20, the target existence likelihood calculation device 20 uses the input information to input the target existence likelihood. Calculate the degree.

(Calculation of sound line depth)
First, the target existence likelihood calculation device 20 calculates the sound line depth by the sound line calculator 21. The sound line calculator 21 performs sound line calculation processing using the environmental information input to the input terminal 1a, the own ship information input to the input terminal 1b, and the arrival elevation angle input to the input terminal 1f. Then, the sound line calculator 21 calculates _{three sound lines for the elevation angles “φ−σ Φ} ”, “φ”, and “φ + σ _Φ ” by the sound line calculation process. Then, the sound line calculator 21 calculates the sound line depths z (φ−σ _Φ , r), z (φ, r) and z (φ + σ _Φ , r) for each distance r in the calculated three sound lines. calculate. Here, "σ _Φ " is the standard deviation of the arrival angle of the signal depending on the measurement accuracy of the angle.

(Calculation of target existence likelihood)
Next, the target existence likelihood calculation device 20 calculates the distance characteristic of the target existence likelihood by the target existence likelihood calculator 22. Target existence likelihood using Eq. (4) based on the sound line depth z (φ−σ _Φ , r), z (φ, r) and z (φ + σ _{Φ, r) input from the sound line calculator 21.} The distance characteristic p _EL (r | φ) of is calculated. In the formula (4), _{"z t"} is the target depth. Further, the function f is the same as that shown in the equation (3) in the first embodiment. _{Further, "σ z} " in the equation (4) can be calculated using, for example, the equation (5).

The standard deviation σ _z may be calculated using an equation other than the equation (5). For example, the average is 0, the random number [Delta] [phi with standard deviation sigma _phi is generated by N, and calculates a sound ray depth z (φ + Δφ, r) against each sound ray depth z (φ + Δφ, r) the standard deviation of It may be calculated.

FIG. 7 is a schematic view showing an example of the target existence likelihood calculated by the target existence likelihood calculator 22 of FIG. In FIG. 7, the horizontal axis represents the distance r from the own ship to the target, and the vertical axis represents the target existence likelihood _pEL (r | φ). By calculating the target existence likelihood as described above, as shown in FIG. 7, the target existence likelihood _pEL (r | RL) corresponding to the distance r from the own ship to the target object is calculated. Then, in the second embodiment, it is determined that the target exists at the position at the distance from the own ship where the value of _{the target existence likelihood pEL (r | RL) thus obtained is the highest.} be able to.

The target existence likelihood calculator 22 _{can perform a calculation using the equation (4) for a plurality of target depths z t_n} (n = 1, 2, ..., N). By calculating multiple target existence likelihoods corresponding to multiple target depths z _{t_n} and displaying the calculated multiple target existence likelihoods on a color map, not only the distance direction from the own ship to the target object but also the target It is possible to grasp the change in the target existence likelihood in the depth direction of an object.

FIG. 8 is a schematic view showing an example of a calculation result when the target existence likelihood calculator 22 of FIG. 6 calculates the target existence likelihood for a plurality of target depths. 8, the horizontal axis represents the distance r from Time to the target, the vertical axis indicates the depth z _t of the target. The target existence likelihood p _EL (r | RL) is indicated by the color state on the color map. Then, in the second embodiment, if the target exists at the position of the distance and the depth from the own ship where the value of _{the target existence likelihood pEL (r | RL) thus obtained is the highest.} You can judge.

As described above, according to the second embodiment, the target existence likelihood is calculated using the arrival elevation angle of the signal radiated from the target as the information regarding the signal received from the target, and thus the own ship. The distance from the target to the target can be determined quickly. In addition, by calculating the target existence likelihood at a plurality of target depths, it is possible to grasp the distance direction and the depth direction from the own ship to the target object. Therefore, the position of the target from the own ship where the target exists can be estimated more accurately.

Embodiment 3.
Next, Embodiment 3 of the present invention will be described. The third embodiment is a combination of the target existence likelihood calculation device 10 according to the first embodiment and the target existence likelihood calculation device 20 according to the second embodiment. In the following description, the parts common to the first and second embodiments are designated by the same reference numerals, and detailed description thereof will be omitted.

[Configuration of target existence likelihood calculation device]
FIG. 9 is a block diagram showing an example of the configuration of the target existence likelihood calculation device 100 according to the third embodiment. As shown in FIG. 9, the target existence likelihood calculation device 100 includes the target existence likelihood calculation device 10 according to the first embodiment, the target existence likelihood calculation device 20 according to the second embodiment, and the integrator 30. It is composed of.

The target existence likelihood calculation device 10 includes input terminals 1a to 1e and output terminals 2a. Similar to the first embodiment, the target existence probability calculation device 10 includes environmental information input to the input terminal 1a, own ship information input to the input terminal 1b, target information input to the input terminal 1c, and the target information. The distance characteristic of the first likelihood is calculated based on the measured reception level from the target object input to the input terminal 1d and the frequency information of the signal from the target object input to the input terminal 1e. The target existence likelihood calculation device 10 outputs the calculated first target existence likelihood to the integrator 30 via the output terminal 2b.

The target existence likelihood calculation device 20 includes input terminals 1a, 1b and 1f, and an output terminal 2b. Similar to the second embodiment, the target existence likelihood calculation device 20 includes the environmental information input to the input terminal 1a, the own ship information input to the input terminal 1b, and the arrival elevation angle input to the input terminal 1f. Based on, the distance characteristic of the second target existence likelihood is calculated. The target existence likelihood calculation device 20 outputs the calculated second target existence likelihood to the integrator 30 via the output terminal 2b.

The integrator 30 is provided with input terminals 1g and 1h on the input side and an output terminal 2c on the output side. The target existence likelihood calculation device 10 is connected to the input terminal 1g, and the first target existence likelihood calculated from the target existence likelihood calculation device 10 is input. Further, the target existence likelihood calculation device 20 is connected to the input terminal 1h, and the second target existence likelihood calculated from the target existence likelihood calculation device 20 is input.

The integrator 30 performs an integration process for integrating the input first target existence likelihood and second target existence likelihood, and calculates the distance characteristic of the third target existence likelihood. The integrator 30 outputs the calculated third target existence likelihood from the output terminal 2c.

[Calculation method of target existence likelihood]
Next, a method of calculating the target existence likelihood in the target existence likelihood calculation device 100 according to the third embodiment will be described. In the third embodiment, the target existence likelihood calculation device 10 calculates the first target existence likelihood as described in the first embodiment. Further, in the target existence likelihood calculation device 20, the second target existence likelihood is calculated as described in the second embodiment. Then, the integrator 30 performs an integration process for integrating the first target existence likelihood and the second target existence likelihood, and calculates the distance characteristic of the third target existence likelihood.

FIG. 10 is a schematic diagram for explaining the integration process performed by the multiplier 30 of FIG. As shown in FIG. 10, the integrator 30 integrates the first target existence likelihood p _RL (r | RL) and the second target existence likelihood p _EL (r | RL), and the third target. The distance characteristic of the existence likelihood (hereinafter, appropriately referred to as “third target existence likelihood”) p (r) is calculated. The integration of the first target existence likelihood p _RL (r | RL) and the second target existence likelihood p _EL (r | RL) is performed based on the equation (6).

In this way, by integrating the first target existence likelihood p _RL (r | RL) and the second target existence likelihood p _EL (r | RL), the third target existence likelihood, which is an integrated value, is present. The degree p (r) reduces the likelihood in the distance range where one of the two target existence likelihoods has a lower likelihood. Then, the third target existence likelihood p (r) is narrowed down to a distance range in which the likelihoods of both are high. Then, in the third embodiment, it is determined that the target exists at the position of the distance and the depth from the own ship at the position where the value of the target existence likelihood p (r) thus obtained is the highest. Can be done.

As described above, in the third embodiment, the target existence likelihood calculated as described in the first embodiment and the target existence likelihood calculated as described in the second embodiment are integrated. Therefore, the likelihood in the distance range where the likelihood is low in any of the target existence likelihoods is reduced. Therefore, it is possible to obtain the target existence likelihood with the ambiguity of the target existence range reduced.

Although the first to third embodiments have been described above, the present invention is not limited to the first to third embodiments described above, and various modifications and applications can be made without departing from the gist of the present invention. Is.

For example, in the third embodiment, the target existence likelihood calculation device 10 _{corresponds to I frequencies f 1} , f ₂ , ..., F _I, and the predicted reception levels RL ₁ , RL ₂ , ..., RL _I. The first target existence likelihood p _RL (r | RL) is acquired, and the target existence likelihood calculation device 20 has J arrival elevation angles φ ₁ , φ ₂ , ..., φ _J. Consider the case where the second target existence likelihood _pEL (r | RL) is acquired. In this case, for example, using the equation (7), all the first target existence likelihood p _RL (r | RL) and the second target existence likelihood p _EL (r | RL) are integrated. The final target existence likelihood p (r) may be calculated.

1a, 1b, 1c, 1d, 1e, 1f, 1g, 1h input terminal, 2a, 2b, 2c output terminal, 10 target existence likelihood calculator, 11 propagation loss calculator, 12 predicted reception level calculator, 13 target existence Likelihood calculator, 20 target existence likelihood calculation device, 21 sound line calculator, 22 target existence likelihood calculator, 30 totalizer, 100 target existence likelihood calculation device.

Claims (6)

It is a target existence likelihood calculation device that is mounted on a sonar device that estimates the distance to a target and calculates the target existence likelihood that indicates the likelihood of the position where the target exists.
Environmental information indicating the environmental state around the sonar device, own ship information indicating the state of the ship on which the sonar device is mounted, actual measurement reception level of a signal radiated from the target, and obtained from the target. A first input unit into which target information and frequency information of the signal are input, and
A first likelihood calculation unit that calculates a first target existence likelihood based on the environmental information, the own ship information, the actual measurement reception level, the target information, and the frequency information input to the first input unit. When
With
The first likelihood calculation unit is
A propagation loss calculator that calculates the propagation loss at a preset target depth based on the environmental information, the own ship information, and the frequency information.
A predicted reception level calculator that calculates a predicted reception level indicating a predicted value of a signal radiated from the target based on the target information from the target and the calculated propagation loss.
With the first target existence likelihood calculator that calculates the first target existence likelihood based on the actually measured reception level from the target and the calculated predicted reception level.
First target existence likelihood calculation device having
Before verge border information, before Symbol own ship information, a second input unit for the incoming Fu elevation of the signal emitted is received from the target,
The environment information input to the second input section, based on the Time information and the incoming Fu elevation, and a second likelihood calculator for calculating a second target exists likelihood,
The second likelihood calculation unit is
A sound line calculator that calculates the sound line depth at a preset target depth based on the environmental information, the own ship information, and the arrival elevation angle.
Based on the calculated acoustic line depth, and a second target exists likelihood calculating device having a second target exists likelihood calculator for calculating the second target presence likelihood,
The first target existence likelihood calculated by the first target existence likelihood calculation device and the second target existence likelihood calculated by the second target existence likelihood calculation device are integrated. With an integrator
Target existence likelihood calculation device according to claim <br/> comprise a. The target existence likelihood calculation device according to claim 1, further comprising a display unit for displaying the calculated target existence likelihood. The second target existence likelihood calculator is
The target existence likelihood calculation device according to claim 1 or 2, wherein the target existence likelihood at a plurality of target depths is calculated. The propagation loss calculator is
The target existence likelihood calculating device according to any one of claims 1 to 3, wherein the propagation loss at a plurality of target depths is calculated. The first target existence likelihood calculation device is
The plurality of first target existence likelihoods are calculated for the actually measured reception levels corresponding to the plurality of frequencies.
The second target existence likelihood calculation device is
Calculate the plurality of second target existence likelihoods for a plurality of incoming elevation angles, and calculate
The integrator
Claims 1 to 4 are characterized in that a value obtained by integrating a plurality of the first target existence likelihoods and a value obtained by integrating a plurality of the second target existence likelihoods are integrated. The target existence likelihood calculation device according to any one of the above items. It is a target existence likelihood calculation method that is mounted on a sonar device that estimates the distance to a target and calculates the target existence likelihood that indicates the likelihood of the position where the target exists.
Environmental information indicating the environmental state around the sonar device, own ship information indicating the state of the ship on which the sonar device is mounted, actual measurement reception level of a signal radiated from the target, and obtained from the target. The first input step in which the target information and the frequency information of the signal are input, and
A propagation loss calculation step for calculating a propagation loss at a preset target depth based on the input environmental information, own ship information, and frequency information.
A predicted reception level calculation step for calculating a predicted reception level indicating a predicted value of a signal radiated from the target based on the target information from the target and the calculated propagation loss.
The first likelihood calculation step of calculating the first target existence likelihood based on the actually measured reception level from the target and the calculated predicted reception level, and
Before verge border information, before Symbol own ship information, a second input step of an arrival Fu elevation of the signal emitted is received from the target,
A sound line calculation step for calculating the sound line depth at a preset target depth based on the input environmental information, the own ship information, and the arrival elevation angle, and
Based on the calculated acoustic line depth, and the second likelihood calculating step of calculating a second target exists likelihood,
An integration step that integrates the first target existence likelihood calculated in the first likelihood calculation step and the second target existence likelihood calculated in the second likelihood calculation step. A target existence likelihood calculation method characterized by providing br />.

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