Acoustic propagation simulation device and acoustic propagation simulation method

Abstract

To provide a fast computation method capable of taking the Doppler effect into account as an acoustic propagation simulation method that can be applied to real-time simulation.SOLUTION: An acoustic propagation simulation device provided herein is configured to perform Doppler effect reproduction processing for reflecting Doppler effect determination elements on transmission waveform time-series data to generate a Doppler-accounted transmission waveform accounted for the Doppler effect, and convolve the Doppler-accounted transmission waveform with a reception wave impulse response to derive reception wave time-series data.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to an acoustic propagation simulation device and an acoustic propagation simulation method. [Background technology]

[0002] Object detection sensors that use wave phenomena that propagate through space include radar, which uses electromagnetic waves, and sonar, which uses sound waves. These devices emit electromagnetic or sound waves, capture the reflected waves when they bounce off the surface of an object, and measure the distance to the object from the time it takes for the reflected waves to return. It is also possible to measure the relative speed of an object based on the change in frequency of the reflected waves. To give a familiar example, ultrasonic sensors are used in corner sensors installed in modern automobiles to avoid collisions at the four corners and at the front and rear of the vehicle, while electromagnetic waves are used in millimeter-wave radar to determine the distance between the vehicle and the vehicle ahead and to prevent rear-end collisions.

[0003] In the air, electromagnetic waves, including visible light, are primarily used, with sound waves being treated similarly. Underwater, however, electromagnetic waves, including visible light, quickly attenuate over short distances. Therefore, sound has long been used for wide-area underwater exploration and long-distance communication, leading to the development of sonar for underwater exploration and situational awareness. Sonar is widely used not only for surveillance and monitoring from a national security perspective, but also for fish detection, marine resource exploration, and undersea topography and crust surveys.

[0004] On the other hand, while sound waves are resistant to attenuation and can travel long distances, their propagation speed is extremely slow compared to light, so the reflected sound that arrives after multiple reflections on the ground and walls and takes multiple paths cannot be ignored compared to direct sound. Furthermore, sound waves that propagate long distances are strongly affected by the non-uniformity of the speed of sound. In other words, the reflected sound does not simply travel in a straight line, but is refracted and distorts the propagation path as it travels.

[0005] Furthermore, as mentioned above, the speed of movement of the sound source, sound receiving point, and reflecting surface cannot be ignored compared to the speed of sound, so the Doppler effect occurs, which causes the received frequency to change relative to the transmitted frequency.As the behavior of long-distance sound waves is complex, when making measurements using sound waves, it is necessary to predict these phenomena and then remove reverberation components from the received sound waves or correct the Doppler effect.

[0006] Several sound field simulation technologies that take these various conditions into account have been proposed. For example, Patent Document 1 shows a sound field prediction method based on wave acoustics theory that is premised on the design of a three-dimensional stereophonic sound system used in the air, and describes a technology that accurately simulates frequency-dependent phenomena such as diffraction.

[0007] In contrast to this, Patent Document 2 describes a method for reproducing the Doppler effect, which is an issue when applying the technology of Patent Document 1 to underwater acoustics, by emitting multiple small signals with sequentially different transmission times and calculating the Doppler effect based on their arrival times.

[0008] Furthermore, Patent Document 3 describes a method for reproducing underwater sound fields that achieves both high speed and high accuracy by combining the ray tracing method, which allows for fast calculations, with the normal mode method, which has high accuracy.

[0009] Furthermore, Patent Document 4 describes an improvement in the efficiency of signal processing related to waveform compression delay when reproducing the Doppler effect. [Prior art documents] [Patent documents]

[0010] [Patent Document 1] Japanese Patent Application Laid-Open No. 2002-159097 [Patent Document 2] Japanese Patent Publication No. 2020-118747 [Patent Document 3] Japanese Patent Application Laid-Open No. 2003-161773 [Patent Document 4] Japanese Patent Publication No. 2022-130763 Summary of the Invention [Problem to be solved by the invention]

[0011] As mentioned above, several sound field simulation technologies have been proposed, but there is no method that can perform real-time simulation taking the Doppler effect into account.

[0012] For example, the above-mentioned Patent Document 1 originally assumed an aerial sound field, and is unable to reproduce the distribution of sound speed or the Doppler effect. In addition, since the calculations are based on wave theory, the calculations take a long time and are not suitable for real-time simulation.

[0013] Patent Document 2 radiates two or more small signals with sequentially different transmission times and calculates the Doppler effect based on their arrival time, but this method takes more than twice as long as not simulating the Doppler effect.

[0014] Furthermore, although Patent Document 3 can achieve both high speed and high accuracy in calculations, it does not incorporate a mechanism for reproducing the Doppler effect.

[0015] Patent Document 4 relates to a signal processing method for reproducing a Doppler waveform, but does not mention spatial propagation of the waveform.

[0016] An object of the present invention is to provide a high-speed calculation method that can take the Doppler effect into account as an acoustic propagation simulation method that can be applied to real-time simulation. [Means for solving the problem]

[0017] An acoustic propagation simulation device according to one aspect of the present invention is an acoustic propagation simulation device having a simulated sound field formation processing unit, a reception judgment processing unit, and a received waveform formation processing unit, wherein the simulated sound field formation processing unit forms a simulated sound field based on simulated sound field information, and the reception judgment processing unit performs time evolution processing of a sound wave surface radiated from the sound source, reflection judgment processing of sound waves, and reception judgment processing of the sound waves at the sound receiving point based on the simulated sound field, the position and speed of a sound source, and the position and speed of a sound receiving point, and the time evolution processing and the reception judgment processing result in The generated received wave impulse response at the sound receiving point and a Doppler effect determination element of the Doppler effect calculated according to the speed of the sound source and the speed of the sound receiving point are output, and the received waveform formation processing unit generates a Doppler-considered transmitted waveform that takes the Doppler effect into consideration by a Doppler effect reproduction process that reflects the Doppler effect determination element on transmitted waveform time series data, and calculates received waveform time series data by convolving the received wave impulse response with the Doppler-considered transmitted waveform. [Effects of the Invention]

[0018] According to one aspect of the present invention, it is possible to provide a high-speed calculation method that can take the Doppler effect into account as an acoustic propagation simulation method that can be applied to real-time simulation. [Brief explanation of the drawings]

[0019] [Figure 1] FIG. 1 is a diagram illustrating a configuration of an acoustic propagation simulation device according to a related art technique. [Figure 2] 1 is a diagram showing the configuration of an acoustic propagation simulation device according to an embodiment of the present invention. [Figure 3] FIG. 1 is a diagram showing the configuration of an acoustic propagation simulation device according to an embodiment of the present invention, illustrating an example in which the device is applied to underwater acoustics. [Figure 4] 3 is a diagram illustrating the wavefront time evolution and reception determination processing shown in FIG. 2. FIG. [Figure 5] 5 is a diagram illustrating the determination of reflection of a sound wave in the wavefront time evolution and reception determination process shown in FIG. 4. FIG. [Figure 6] 10 is a diagram illustrating a method for calculating a Doppler effect determination element based on sound source velocity information of a particle and moving velocity information of a sound receiving point. FIG. [Figure 7] 6 is a diagram illustrating a method for calculating Doppler effect determination elements under special conditions for determining the reflection of sound waves shown in FIG. 5. FIG. [Figure 8] FIG. 10 is a diagram illustrating an example of a display screen that displays the position and moving speed of a sound source based on an observed sound pressure waveform. DETAILED DESCRIPTION OF THE INVENTION

[0020] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0021] FIG. 1 is a diagram showing the configuration of an acoustic propagation simulation device according to the related art.

[0022] In the simulation that the present invention aims to solve, as shown in Figure 1, first, a simulated sound field 19 is formed based on simulated sound field formation processing 10, based on the distribution of terrain and obstacles, acoustic characteristics such as the sound reflection rate on the ground and obstacles, and simulated sound field information 11 that indicates the distribution of sound speed in the simulation space.

[0023] Next, based on the simulated sound field 19 and the time history information of the position and velocity 21 of the set sound source, and further based on the time history information of the position and velocity 22 of the sound receiving point, a process 30 is performed to determine the time evolution of the sound wave front emitted from the sound source and the reception of the sound wave at the sound receiving point.

[0024] This sound wave front time evolution and sound wave reception determination process 30 at the sound receiving point is made up of sound wave front time evolution process 31, sound wave reflection determination 32, sound wave reception determination 33, and time update process 34. Of these, the sound wave front time evolution process 31, sound wave reflection determination 32, and sound wave reception determination 33 are processed in any order, or are optimized to suit the set target problem.

[0025] As a result of the wavefront time evolution 31 and the sound wave reception decision process 33 at the sound receiving point, a received wave impulse response 38 at the sound receiving point is output. Finally, based on the obtained received wave impulse response 38 at the sound receiving point and the time series data 41 of the transmitted waveform at the sound source, the data is finally stored as received waveform time series data 54 based on the received waveform formation process 50. Note that this received waveform formation process 50 is made up of a convolution operation process 53 that outputs received waveform time series data 54 based on the transmitted waveform time series data 41 and the received wave impulse response 38.

[0026] Even with these related technologies, it is possible to calculate the received waveform according to the position and speed of a sound source or receiving point that changes over time. However, if the speed of movement of these sound sources or receiving points is not small enough to be ignored compared to the speed of sound, the Doppler effect that occurs cannot be simulated. Therefore, there is a problem in that it is impossible to determine the speed of movement of the sound source or receiving point based on the received waveform.

[0027] The present invention provides an acoustic propagation simulation device that solves the problems of the related art. The present invention provides a high-speed calculation method that can take the Doppler effect into account as an acoustic propagation simulation method that can be applied to real-time simulation.

[0028] The configuration of the acoustic propagation simulation device according to the embodiment of the present invention will be described below with reference to FIG.

[0029] The acoustic propagation simulation device according to the embodiment of the present invention shown in FIG. 2 differs from the acoustic propagation simulation device according to the related art shown in FIG. 1 in that, as a result of the time evolution of the wavefront 31 and the sound wave reception determination process 33 at the sound receiving point, not only the received wave impulse response 38 at the sound receiving point but also the Doppler effect determination element 39 calculated according to the velocities of the sound source and the sound receiving point is output.

[0030] In addition, the received waveform formation process 50 generates a Doppler-considered transmitted waveform 52 by a Doppler effect reproduction process 51 that reflects the Doppler effect determination element 39 on the transmitted waveform time series data 41, and stores the Doppler-considered transmitted waveform 52 as received waveform time series data 54 by convolving the received wave impulse response 38 with the Doppler-considered transmitted waveform 52.

[0031] Furthermore, a screen display process 70 is performed to visualize the position and velocity of the sound source based on a plurality of observed sound pressure waveforms.

[0032] By performing this processing, it is possible to calculate a received waveform that takes into account the Doppler effect that occurs when the sound source position and the sound receiving point position are moving. The other configurations are the same as those of the acoustic propagation simulation device of the related art shown in Figure 1, so a description thereof will be omitted.

[0033] Figure 3 shows an example of the acoustic propagation simulation method described in Figure 2 when applied to an underwater sound field.

[0034] The multiple pieces of sound field simulation information 11 shown in Fig. 2 are converted into seabed topography or water depth distribution 11a, 11b, the composition of sedimentary layers on the seabed and their acoustic characteristics 11c, 11d, and the sound speed distribution 11e of the simulated sea area, and based on these, a sound field 19 of the simulated sea area is calculated by the simulated sound field formation process 10. The subsequent processing is the same as in Fig. 2, and ultimately it is possible to calculate a received waveform that takes the Doppler effect into account.

[0035] FIG. 4 is a diagram for explaining that the time evolution of the sound wave front and the reception decision process in the embodiment shown in FIGS. 2 and 3 are calculated using a calculation method called the ray theory or particle method.

[0036] In a method known as ray theory or particle method, wave phenomena are expressed using particles 60 emitted from a sound source and their trajectories, sound rays 62. In other words, the wavefront 61 of sound emitted from a sound source is expressed as an envelope of countless particles 60 emitted from the sound source, and the propagation of the wavefront is simulated as the envelope of these numerous particles 60 spreads and moves away from the sound source over time.

[0037] The algorithm implemented in this system distorts the trajectory of the particle 60 during propagation to simulate refraction due to the influence of the sound speed distribution in the medium. The particle 60 also reflects off the ground or an obstacle, and when this happens, it undergoes conformal reflection, where the angle of incidence and the angle of reflection are equal to the reflecting surface, and the energy attenuates during reflection depending on the acoustic properties of the medium or obstacle.

[0038] In this way, particles 60 that reach the sound receiving point are observed at the sound receiving point, and the time and energy thereof are recorded. The time and energy of the particle group at the sound receiving point recorded in this way are treated as a received wave impulse response 38, and in the subsequent received waveform formation process 50, a convolution operation 53 is performed on a Doppler-considered transmitted waveform 52 to obtain received waveform time series data 54.

[0039] The Doppler effect associated with the movement of a sound source or sound receiving point is realized by providing particles 60 with information about the sound source that emitted the particle 60. Specifically, the information is output as a Doppler effect determination element 39 based on the sound source speed information possessed by the particle 60 and the moving speed of the sound receiving point, and later, during the received waveform formation process 50, it is subjected to a Doppler effect reproduction process 51 together with transmitted waveform time series data 41 to output a Doppler-considered transmitted waveform 52. A specific calculation method for the Doppler effect determination element 39 will be described later.

[0040] By performing this type of processing, it is possible to calculate sound wave propagation by implementing the received waveform, which takes into account the Doppler effect that occurs when the sound source position and the receiving point position are moving, into a method called ray theory or particle method.

[0041] Figure 5 is a diagram used to explain how, when calculating acoustic propagation while implementing the reproduction of the Doppler effect shown in Figure 4 in a technique called ray theory or particle method, the sound wave reflection judgment involves conformal reflection of the particle's velocity information about the sound source, as well as particle reflection.

[0042] In acoustic propagation calculations known as ray theory or particle method, an algorithm is implemented in advance to cause particles to be conformally reflected from the surface of a reflecting object when sound waves are reflected from the object. However, this algorithm is extended and modified so that the velocity information 63 of the sound source that emitted the particle 60 itself is also conformally reflected from the surface of the object.

[0043] By performing such processing, the sound source velocity information 63 possessed by the particle 60 after reflection indicates the moving velocity 63 of the mirror image sound source relative to the surface of the reflecting object, which is the same as the behavior of the particle 60 emitted from the mirror image moving sound source virtually set on the opposite side of the surface of the reflecting object, and it is possible to anticipate that the calculation of the Doppler effect determination element 39 after reflection can be performed correctly.

[0044] FIG. 6 is a diagram for explaining the calculation of the Doppler effect determination element.

[0045] The Doppler effect determination element 39 is shown in Equation 1 in the figure, and the frequency f' of the observed sound wave fluctuates at a certain ratio to the frequency f of the sound wave emitted from the sound source. The fluctuation is expressed as c for the sound speed and v for the wavefront propagation direction component of the sound source speed. s ', the component of the velocity at the receiving point in the wavefront propagation direction is v r This indicates that it can be expressed as Equation 1 as '.

[0046] In a method known as ray theory or particle method, when a particle 60 arrives at the receiving point 22, it is observed as a pulse wave, and the component of the receiving point velocity in the wavefront propagation direction can be determined using related technology. However, because there is no information about the sound source velocity 63, the denominator of Equation 1 cannot be calculated correctly, and the Doppler effect determination factor 39 cannot be calculated correctly.

[0047] To correctly evaluate the denominator in Equation 1, which is due to the sound source velocity 63, information on the sound source's moving speed is required. Patent Document 2, for example, proposes a method for obtaining this information. This involves instantly emitting two particles from the sound source and determining the sound source's moving speed based on the time interval between their observations. In other words, the sound source's moving speed is determined based on the difference in reception time between the first particle emitted and the particle emitted with a slight time delay. For example, if the difference in reception time is shorter than the difference in emission time, it can be determined that the sound source is approaching; if it is longer, it can be determined that the sound source is receding. However, this method clearly doubles the computational cost.

[0048] Therefore, in the present invention, by providing particle 60 with sound source velocity information 63, even if the particle 60 emitted from the sound source is a single shot, information on the wavefront propagation direction component of sound source velocity 63, which is necessary for sound reception judgment, can also be obtained, making it possible to calculate Equation 1.

[0049] This makes it possible to calculate sound wave propagation by implementing received waveforms that take into account the Doppler effect that occurs when the sound source position and the receiving point position are moving into a method known as ray theory or particle method.

[0050] Figure 7 shows how to handle the case where the sound velocity distribution in the sound field to be calculated is constant.

[0051] When the condition that the sound speed distribution of the sound field to be calculated is constant is met, the particle movement direction remains the same as the direction of radiation from the sound source unless it is reflected by a reflecting object. Therefore, the angle formed by the particle movement direction vector and the sound source movement velocity vector 63 of the particle 60 is always maintained. This also holds true for the reflection determination when reflecting off a reflecting object, so the angle formed by this particle movement direction vector and the sound source movement velocity vector 63 of the particle 60 is also always maintained after reflection off the reflecting object. Therefore, the sound source velocity information that the particle 60 should have does not need to be held as a vector; it is sufficient to have only the cosine component of the sound source movement velocity relative to the particle radiation direction at the sound source.

[0052] By performing this type of processing, it is possible to reduce the amount of information required when calculating sound wave propagation while taking into account the Doppler effect in a method known as ray theory or particle method.

[0053] FIG. 8 is a diagram illustrating an example of a display screen that displays the position and moving speed of a sound source based on the observed sound pressure waveform.

[0054] 8, as a result of utilizing the acoustic propagation simulation technique, the sound source and the moving speed of the sound source are visualized and displayed based on a plurality of observed sound pressure waveforms. This processing is performed by the screen display processing 70 in FIG. 2.

[0055] When multiple observed sound pressure waveforms are obtained in a simulation, as shown in Figure 8, the position of the sound source can be estimated based on that information, but the present invention also makes it possible to grasp the speed of movement and display it on the screen together with the sound source position.

[0056] In the above embodiments, there are cases where processing performed by executing a program is described. Here, a computer executes the program using a processor (e.g., a CPU or a GPU) and performs processing defined by the program using storage resources (e.g., a memory) and interface devices (e.g., a communication port). Therefore, the entity performing the processing by executing the program may be the processor. Similarly, the entity performing the processing by executing the program may be a controller, device, system, computer, or node having a processor. The entity performing the processing by executing the program may be any computing unit, and may include a dedicated circuit that performs specific processing. Here, the dedicated circuit may be, for example, an FPGA (Field Programmable Gate Array), an ASIC (Application Specific Integrated Circuit), or a CPLD (Complex Programmable Logic Device).

[0057] A program may be installed on a computer from a program source. The program source may be, for example, a program distribution server or a computer-readable storage medium. When the program source is a program distribution server, the program distribution server may include a processor and a storage resource for storing the program to be distributed, and the processor of the program distribution server may distribute the program to be distributed to other computers. In addition, in an embodiment, two or more programs may be realized as one program, or one program may be realized as two or more programs.

[0058] Specifically, the simulated sound field formation processing 10 shown in Fig. 2 is implemented as a simulated sound field formation processing unit by a processor executing a program. The sound wave front time evolution and reception judgment processing 30 is implemented as a sound wave front time evolution and reception judgment processing unit by a processor executing a program. The received waveform formation processing 50 is implemented as a received waveform formation processing unit by a processor executing a program. The screen display processing 70 is implemented as a screen display processing unit by a processor executing a program.

[0059] According to the above embodiment, it is possible to provide a high-speed calculation method that can take into account the Doppler effect and reflections on object surfaces as an acoustic propagation simulation method that can be applied to real-time simulation.

[0060] Furthermore, a method for real-time simulation that takes the Doppler effect into account can be provided without significantly increasing the calculation cost. [Explanation of symbols]

[0061] 1. Acoustic propagation simulation device 10 Simulated sound field formation processing 30 Time evolution of wavefront and reception decision processing 31 Time evolution processing of wave fronts 32 Determining the reflection of sound waves 33. Sound wave reception determination 34 Hourly Update Process 38 Impulse response of received wave 39 Doppler Effect Determination Factors 41 Transmitted waveform time series data 50 Received waveform formation processing 51 Doppler effect reproduction processing 52 Doppler-considered transmission waveform 53 Convolution processing 54 Received waveform time series data 60 particles 61 Wavefront 62 Sound Rays 63 Sound source velocity information 70 Screen display processing

Claims

1. An acoustic propagation simulation device having a simulated sound field forming processing unit, a reception judgment processing unit, and a received waveform forming processing unit, The simulated sound field forming processing unit includes: forming a simulated sound field based on the simulated sound field information; The reception determination processing unit Based on the simulated sound field, the position and velocity of the sound source, and the position and velocity of the sound receiving point, a time evolution process of the sound wave surface radiated from the sound source, a reflection determination process of the sound wave, and a reception determination process of the sound wave at the sound receiving point are performed; outputting a received wave impulse response at the sound receiving point generated by the time evolution processing and the reception determination processing, and a Doppler effect determination element of the Doppler effect calculated according to the speed of the sound source and the speed of the sound receiving point; The received waveform forming processing unit generating a Doppler-considered transmission waveform that takes the Doppler effect into consideration by a Doppler effect reproduction process that reflects the Doppler effect determination factor on the transmission waveform time series data; An acoustic propagation simulation device, characterized in that received waveform time series data is calculated by convolving the Doppler-considered transmitted waveform with the received wave impulse response.

2. The simulated sound field forming processing unit includes:

2. The acoustic propagation simulation device according to claim 1, wherein aerial sound field information of an object existing in the air is used as the simulated sound field information.

3. The simulated sound field forming processing unit includes:

3. The acoustic propagation simulation device according to claim 2, wherein the simulated sound field is formed based on the aerial sound field information, such as the distribution of topography and obstacles, and the acoustic characteristics or sound speed distribution of the ground and obstacles.

4. The simulated sound field forming processing unit includes:

2. The acoustic propagation simulation device according to claim 1, wherein underwater sound field information of an object existing underwater is used as the simulated sound field information.

5. The simulated sound field forming processing unit includes:

5. The acoustic propagation simulation device according to claim 4, wherein the simulated sound field in the simulated sea area is formed based on the underwater sound field information, such as seabed topography, the structure and acoustic characteristics of the sedimentary layers on the seabed, or the sound speed distribution in the simulated sea area.

6. The reception determination processing unit 2. The acoustic propagation simulation device according to claim 1, wherein the Doppler effect is realized by adding information about the sound source to particles emitted from the sound source as sound source information.

7. The reception determination processing unit 7. The acoustic propagation simulation device according to claim 6, wherein the Doppler effect determination element is output based on the sound source velocity and the sound receiving point velocity, which are the sound source information assigned to the particle.

8. The reception determination processing unit In the sound wave reflection determination process, assigning a position and a velocity of the sound source as the sound source information to the particles emitted from the sound source; 7. The acoustic propagation simulation device according to claim 6, wherein the reflection determination process is performed not only on the moving direction of the particle at the time of reflection, but also on the speed of the sound source assigned to the particle.

9. The reception determination processing unit The velocity of the sound source, which is the sound source information assigned to the particle, is 7. The acoustic propagation simulation device according to claim 6, wherein the sound source velocity is expressed as a sound source velocity vector.

10. The reception determination processing unit When the condition that the sound speed distribution of the sound field is constant is satisfied, The velocity of the sound source, which is the sound source information assigned to the particle, is 7. The acoustic propagation simulation device according to claim 6, wherein the sound source velocity is expressed as a particle movement direction cosine component.

11. The received waveform forming processing unit 2. The acoustic propagation simulation device according to claim 1, wherein the received waveform time series data is calculated taking into account the Doppler effect that occurs when the position of the sound source and the position of the sound receiving point are moving.

12. 2. The acoustic propagation simulation device according to claim 1, further comprising a screen display processing unit that visualizes the position and velocity of the sound source based on a plurality of observed sound pressure waveforms and performs screen display processing.

13. The screen display processing unit Displaying the distance, direction, and altitude as the location of the sound source; 13. The acoustic propagation simulation device according to claim 12, wherein a sound source velocity vector is displayed as the velocity of the sound source.

14. An acoustic propagation simulation method having a simulated sound field forming processing step, a reception determination processing step, and a received waveform forming processing step, The simulated sound field forming processing step includes: The simulated sound field forming processing unit forming a simulated sound field based on the simulated sound field information; The reception determination processing step includes: The reception determination processing unit Based on the simulated sound field, the position and velocity of the sound source, and the position and velocity of the sound receiving point, a time evolution process of the sound wave surface radiated from the sound source, a reflection determination process of the sound wave, and a reception determination process of the sound wave at the sound receiving point are performed; outputting a received wave impulse response at the sound receiving point generated by the time evolution processing and the reception determination processing, and a Doppler effect determination element of the Doppler effect calculated according to the speed of the sound source and the speed of the sound receiving point; The received waveform forming processing step includes: The received waveform forming processing unit generating a Doppler-considered transmission waveform that takes the Doppler effect into consideration by a Doppler effect reproduction process that reflects the Doppler effect determination factor on the transmission waveform time series data; An acoustic propagation simulation method, comprising: calculating received waveform time series data by convolving the Doppler-considered transmitted waveform with the received wave impulse response.

15. The reception determination processing step includes: The acoustic propagation simulation method according to claim 14, wherein the Doppler effect is realized by adding information about the sound source to particles emitted from the sound source as sound source information.

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