JP6087850B2 - Acoustic transfer characteristic measuring device, acoustic transfer characteristic measuring method, program - Google Patents

Description

  The present invention relates to a technique for measuring a sound transfer characteristic between a speaker array and a microphone array.

  A conventional technique for measuring sound transfer characteristics uses a Time Stretched Pulse (TSP) signal (Non-Patent Document 1). The TSP signal is a signal obtained by extending a pulse signal in the time direction. The measurement technique of acoustic transfer characteristics of Non-Patent Document 1 is that the TSP signal is output from one speaker and picked up by one microphone, so that the transfer characteristic between a single speaker and a single microphone is obtained. It is a technology that enables highly accurate and robust measurement. When this technology is applied between a large number of speakers and microphones, a TSP signal is output from each speaker, and an acoustic transfer characteristic is calculated by convolving an inverse TSP signal with a signal observed by a microphone array.

Y. Suzuki, F. Asano, H. Kim, and T. Sone. “An optimal computer-generated pulse signal suitable for the measurement of very long impulse responses,” J. Acoust. Soc. Am., Vol. 97, no. 2, pp.1119-1123, 1995.

  In the prior art, when measuring the acoustic transfer characteristics between a large number of speakers and microphones, it is necessary to output a TSP signal from each speaker. Therefore, it takes a long time to measure the characteristics from all the speakers. was there. Therefore, an object of the present invention is to provide an acoustic transfer characteristic measuring apparatus that can shorten the time required for measuring the acoustic transfer characteristic between a speaker and a microphone array.

  The acoustic transfer characteristic measuring apparatus of the present invention includes a speaker array, a microphone array, an STSP signal calculation unit, an inverse STSP signal calculation unit, and a transfer characteristic estimated value calculation unit.

  The speaker array is formed by arranging a plurality of speakers in a straight line. The microphone array is formed by arranging a plurality of microphones in a straight line. The STSP signal calculation unit calculates a spatio-temporal region STSP signal that is a representation of the spatio-temporal region of the STSP signal, which is a signal in which the angle and frequency of the plane wave at the time of synthesis change in the time direction, and outputs it from the speaker array. The inverse STSP signal calculation unit calculates a spatiotemporal domain inverse STSP signal based on the spatiotemporal domain STSP signal. The transfer characteristic estimated value calculation unit calculates an estimated value of the spatio-temporal acoustic transfer characteristic based on the input signal that is a signal collected by the microphone array and the spatio-temporal domain inverse STSP signal.

  According to the acoustic transfer characteristic measuring apparatus of the present invention, the time required for measuring the acoustic transfer characteristic between the speaker and the microphone array can be shortened.

The block diagram which shows the structure of the acoustic transfer characteristic measuring apparatus of Example 1 of this invention. The flowchart which shows operation | movement of the acoustic transfer characteristic measuring apparatus of Example 1 of this invention. The block diagram which shows the structure of the acoustic transfer characteristic measuring apparatus of Example 2 of this invention. The flowchart which shows operation | movement of the acoustic transfer characteristic measuring apparatus of Example 2 of this invention.

  Hereinafter, embodiments of the present invention will be described in detail. In addition, the same number is attached | subjected to the structure part which has the same function, and duplication description is abbreviate | omitted.

<About Space-Time Stretched Pulse (STSP) signal>
Hereinafter, the Space-Time Stretched Pulse (STSP) signal used in the present invention will be defined. The STSP signal is simply a signal obtained by expanding the TSP signal in the spatial direction. Therefore, the STSP signal is a signal obtained by extending a pulse signal in the time direction and the spatial direction, and can also be expressed as a signal in which the angle and frequency of the plane wave at the time of synthesis change in the time direction.

  Hereinafter, the acoustic transfer characteristic measuring apparatus according to the first embodiment will be described with reference to FIGS. 1 and 2. FIG. 1 is a block diagram illustrating a configuration of an acoustic transfer characteristic measuring apparatus 1 according to the present embodiment. FIG. 2 is a flowchart showing the operation of the sound transfer characteristic measuring apparatus 1 of the present embodiment.

  As shown in FIG. 1, the acoustic transfer characteristic measuring apparatus 1 of the present embodiment includes an STSP signal calculation unit 11, a speaker array 12, an inverse STSP signal calculation unit 13, a microphone array 14, and a transfer characteristic estimated value calculation unit. 15 is included. The STSP signal calculator 11 includes a spatio-temporal frequency domain STSP signal calculator 111 and a spatio-temporal domain STSP signal calculator 112. The inverse STSP signal calculator 13 includes a spatiotemporal frequency domain inverse STSP signal calculator 131 and a spatiotemporal domain inverse STSP signal calculator 132.

Speaker array 12 includes a plurality of speakers 12-1, 12-2, ..., formed by arranging in a straight line to _{12-N x.} Microphone array 14, a plurality of microphones 14-1 and 14-2, ..., formed by arranging in a straight line to _{14-N x.} However, N _x is the number of speakers and microphones, and N _x is an arbitrary integer of 2 or more.

<STSP signal calculator 11>
Hereinafter, the STSP signal calculation unit 11 will be described. The spatio-temporal frequency domain STSP signal calculator 111 of the STSP signal calculator 11 converts the spatio-temporal frequency domain STSP signal, which is a representation of the above-mentioned spatio-temporal frequency domain of the STSP signal, under the condition that the temporal frequency and the spatial frequency change linearly. Calculate (S111). More specifically, the spatio-temporal frequency domain STSP signal calculation unit 111 receives the STSP signal design parameters (Δω, ω ₀ , Δk _x , k _x0 ) as input, and the spatio-temporal frequency domain STSP signal F (k _{x, n} , ω _m ) is calculated by the following equation (1), for example.

Where k _{x, n} is the spatial frequency, ω _m is the time frequency, Δω is a parameter for adjusting the increase amount of the time frequency, Δk _x is a parameter for adjusting the increase amount of the spatial frequency, and ω ₀ is the initial value of the time frequency. K _x0 is a parameter for adjusting the initial value of the spatial frequency, n and m are indices of the spatial frequency k _{x, n} and the time frequency ω _{m ,} respectively, 1 ≦ n ≦ N _kx , 1 ≦ m ≦ N _ω . N _kx and N _ω are the spatial frequency bin number and the temporal frequency bin number, respectively. The spatial frequency k _{x, n} and the temporal frequency ω _m are defined as follows, for example.

Here, Δx and Δt are space (speaker / microphone) and time sampling interval, respectively. Next, the spatio-temporal region STSP signal calculator 112 of the STSP signal calculator 11 calculates a spatio-temporal region STSP signal that is a representation of the spatio-temporal region of the STSP signal based on the spatio-temporal frequency region STSP signal. 12 (S112). More specifically, the spatio-temporal domain STSP signal calculation unit 112 applies, for example, a two-dimensional inverse discrete Fourier transform to the above-described spatio-temporal frequency domain STSP signal F (k _{x, n} , ω _m ). A space-time domain STSP signal f (x _i , t _j ) is calculated. The spatio-temporal domain STSP signal calculation unit 112 calculates a spatio-temporal domain STSP signal f (x _i , t _j ) by executing, for example, a two-dimensional inverse discrete Fourier transform defined by the following equation (2).

Here, i and j indicate indexes in the spatial direction (speaker direction) x _i and the time direction t _j . As described above, the N _x is the number of speaker microphones, when the N _t and the time direction of the signal length is an index i, j is _{1 ≦ i ≦ N x, 1} ≦ j ≦ N t. The spatio-temporal region STSP signal calculation unit 112 outputs the spatio-temporal region STSP signal f (x _i , t _j ) from each speaker 12-1, 12-2,..., 12-N _x constituting the speaker array 12. . As specific values of the above-described STSP signal design parameters (Δω, ω ₀ , Δk _x , k _x0 ) and other parameters, for example, Δω = 400, ω ₀ = 0, Δk _x = 4000, k _x0 = 0 , N _x = 512, N _t = 512, Δx = 0.06 m, Δt = 0.625 ms (sampling frequency 16 kHz).

<Inverse STSP signal calculator 13>
Hereinafter, the inverse STSP signal calculation unit 13 will be described. The spatio-temporal frequency domain inverse STSP signal calculator 131 of the inverse STSP signal calculator 13 calculates a spatio-temporal frequency domain inverse STSP signal that is a signal for generating a pulse signal by convolution with the spatio-temporal frequency domain STSP signal (S131). . More specifically, the spatio-temporal frequency domain inverse STSP signal calculation unit 131 receives the STSP signal design parameters (Δω, ω ₀ , Δk _x , k _x0 ) as an input, for example, based on the following equation (3), The frequency domain inverse STSP signal G (k _{x, n} , ω _m ) is calculated.

The spatiotemporal domain inverse STSP signal calculator 132 of the inverse STSP signal calculator 13 calculates a spatiotemporal domain inverse STSP signal based on the spatiotemporal frequency domain inverse STSP signal (S132). More specifically, the spatio-temporal domain inverse STSP signal calculation unit 132 applies, for example, a two-dimensional inverse discrete Fourier transform to the spatio-temporal frequency domain inverse STSP signal G (k _{x, n} , ω _m ). A space-time domain inverse STSP signal g (x _i , t _j ) is calculated. The spatio-temporal domain inverse STSP signal calculation unit 132 performs, for example, a two-dimensional inverse discrete Fourier transform defined by the following equation (4) to calculate a spatio-temporal domain inverse STSP signal g (x _i , t _j ). .

<Transfer characteristic estimated value calculation unit 15>
Hereinafter, the transfer characteristic estimated value calculation unit 15 will be described. The transfer characteristic estimated value calculation unit 15 calculates an estimated value of the spatiotemporal acoustic transfer characteristic based on the input signal that is a signal picked up by the microphone array and the spatiotemporal domain inverse STSP signal (S15). More specifically, the input signals (also referred to as microphone array input signals) f ~ (x _i , t _j ) that are signals collected by the microphone array 14 and the spatio-temporal domain inverse STSP signal g (x _i , t _j ) as input and spatio-temporal acoustic transfer characteristic estimation value h ~ (x _i , t _j ) (or H ~ (k _{x, n} , ω _m ) representing spatio-temporal frequency domain) as output . The estimated value of the spatio-temporal acoustic transfer characteristic output by the transfer characteristic estimated value calculation unit 15 may be a spatio-temporal domain expression or a spatio-temporal frequency domain expression. For example, the transfer characteristic estimated value calculation unit 15 convolves the estimated value of the spatio-temporal acoustic transfer characteristic with the microphone array input signal f˜ (x _i , t _j ) and the spatio-temporal domain inverse STSP signal g (x _i , t _j ). Calculated by The transfer characteristic estimation value calculation unit 15 performs the spatio-temporal acoustic transfer characteristic by using, for example, a method using two-dimensional circular convolution, a method using two-dimensional linear convolution, or a method combining circular convolution and linear convolution. An estimated value can be calculated. An example of these three calculation methods is shown below.

<Method using two-dimensional circular convolution>
When using a two-dimensional circular convolution, the transfer characteristic estimation value calculation unit 15 performs F˜ (k _{x, n} , ω _m ) which is a two-dimensional discrete Fourier transform of the microphone array input signal f˜ (x _i , t _j ). And G (k _{x, n} , ω _m ) _, which is a two-dimensional discrete Fourier transform of the spatio-temporal domain inverse STSP signal g (x _i , t _j ). The transfer characteristic estimated value calculation unit 15 calculates F˜ (k _{x, n} , ω _m ) by executing a two-dimensional discrete Fourier transform defined by the following equation (5), for example.

A signal obtained by multiplying these becomes the estimated value H˜ (k _{x, n} , ω _m ) of the spatiotemporal acoustic transfer characteristic in the spatiotemporal frequency domain. Accordingly, the transfer characteristic estimated value calculation unit 15 calculates the estimated value H˜ (k _{x, n} , ω _m ) of the spatio-temporal acoustic transfer characteristic in the spatio-temporal frequency domain by the following equation (6).

The transfer characteristic estimation value calculation unit 15 converts the spatio-temporal acoustic transfer characteristic estimation values h˜ (x _i , t _j ) in the spatio-temporal region into two-dimensional inverse discrete Fourier transforms H˜ (k _{x, n} , ω _m ). It can be calculated as a conversion. The transfer characteristic estimated value calculation unit 15 may output H˜ (k _{x, n} , ω _m ) as it is.

<Method using two-dimensional linear convolution>
When using the two-dimensional linear convolution, the transfer characteristic estimation value calculation unit 15 performs the following for the microphone array input signal f˜ (x _i , t _j ) and the spatio-temporal domain inverse STSP signal g (x _i , t _j ). By performing the two-dimensional linear convolution as described above, the estimated values h˜ (x _i , t _j ) of the spatiotemporal acoustic transfer characteristics in the spatiotemporal region are directly calculated. Therefore, the transfer characteristic estimated value calculation unit 15 calculates the spatio-temporal acoustic transfer characteristic estimated values h˜ (x _i , t _j ) in the spatio-temporal region by the following equation (7).

χ and τ represent delays in the spatial direction and the time direction, respectively.

<Combination of circular convolution and linear convolution>
Here, for example, consider a case where linear convolution is performed in the spatial direction x _i and circular convolution is performed in the time direction t _j . In this case, the transfer characteristic estimated value calculation unit 15 applies the microphone array input signal f˜ (x _i , t _j ) and the spatio-temporal domain inverse STSP signal g (x _i , t _j ) to both ends in the x _i direction. Signals zeroed by N _x / 2 samples are set as f ⁻ (x _i , t _j ) and g ⁻ (x _i , t _j ), respectively. However, here, 1 ≦ i ≦ 2N _x and 1 ≦ j ≦ N _t . Transfer characteristic estimate calculation unit _{^{15, f - (x i, t}} j), g - (x i, t j) is a two-dimensional discrete Fourier transform of _{^{F - (k x, n,}} ω m), G - Calculate (k _{x, n} , ω _m ). A signal obtained by multiplying these becomes the estimated value H˜ (k _{x, n} , ω _m ) of the spatiotemporal acoustic transfer characteristic in the spatiotemporal frequency domain. Accordingly, the transfer characteristic estimated value calculation unit 15 calculates the spatio-temporal acoustic transfer characteristic estimated values H˜ (k _{x, n} , ω _m ) in the spatio-temporal frequency domain by the following equation (8).

The transfer characteristic estimation value calculation unit 15 calculates the spatio-temporal acoustic transfer characteristic estimation value h˜ (x _i , t _j ) in the spatio-temporal region as a two-dimensional inverse discrete Fourier of H˜ (k _{x, n} , ω _m ). It can be calculated as a conversion. The transfer characteristic estimated value calculation unit 15 may output H˜ (k _{x, n} , ω _m ) as it is. However, in this method, the signal corresponding to the zeroed portion is not treated as a measurement value.

  In the above description, the discrete Fourier transform (and inverse transform) is used as a specific method of the frequency domain-time domain transformation. For example, steps S112, S132, and S15. However, in the present invention, the frequency domain-time domain transformation is not limited to the discrete Fourier transformation (inverse transformation). In steps S112, S132, and S15, the frequency domain-time domain transformation is executed by another method. May be.

  According to the acoustic transfer characteristic measuring apparatus 1 of the present embodiment, the STSP signal calculation unit 11 outputs the STSP signal obtained by extending the pulse signal not only in the time direction but also in the spatial direction from the linearly arranged speaker array 12. The signal is picked up by the microphone array 14 arranged in a straight line, and the transfer characteristic estimated value calculation unit 15 calculates the estimated value of the spatio-temporal acoustic transfer characteristic based on the microphone array input signal and the spatio-temporal domain inverse STSP signal. Therefore, the transfer characteristic can be obtained by one measurement, and the time required for measuring the spatio-temporal acoustic transfer characteristic can be greatly reduced.

  The sound transfer characteristic measuring apparatus 1 of the present embodiment uses a wavefront synthesis method, and is a system for voice communication that realizes a sense of reality by faithfully reproducing sound collected by a microphone array with a remote speaker array. Can be used. The acoustic transfer characteristic measuring apparatus 1 according to the present embodiment is useful for obtaining a transfer characteristic necessary for generating a filter by the wavefront synthesis method.

  Hereinafter, the acoustic transfer characteristic measuring apparatus according to the second embodiment will be described with reference to FIGS. 3 and 4. FIG. 3 is a block diagram showing the configuration of the acoustic transfer characteristic measuring apparatus 2 of the present embodiment. FIG. 4 is a flowchart showing the operation of the sound transfer characteristic measuring apparatus 2 of the present embodiment.

  As shown in FIG. 3, the acoustic transfer characteristic measuring apparatus 2 of the present embodiment includes an STSP signal calculation unit 21, a speaker array 12, an inverse STSP signal calculation unit 23, a microphone array 14, and a transfer characteristic estimated value calculation unit. 15 is included.

  The STSP signal calculator 11 and the inverse STSP signal calculator 13 of the first embodiment are changed to an STSP signal calculator 21 and an inverse STSP signal calculator 23 in the present embodiment. Since other configurations are common in the first embodiment and the second embodiment, description thereof is omitted.

<STSP signal calculator 21>
The STSP signal calculation unit 21 of this embodiment directly calculates the spatio-temporal region STSP signal without performing the calculation in the spatio-temporal frequency region and outputs it from the speaker array (S21). Specifically, the STSP signal calculation unit 21 directly calculates a spatio-temporal region STSP signal by the following equation (9).

<Inverse STSP signal calculator 23>
The inverse STSP signal calculation unit 23 of the present embodiment directly calculates the spatio-temporal domain inverse STSP signal based on the spatio-temporal domain STSP signal without performing the calculation in the spatio-temporal frequency domain (S23). More specifically, the inverse STSP signal calculation unit 23 converts the spatio-temporal domain STSP signal f (x _i , t _j ) calculated by Equation (9) into the spatio-temporal domain inverse STSP signal. To do. Specifically, the inverse STSP signal calculation unit 23 directly calculates a spatio-temporal domain inverse STSP signal by the following equation (10).

  According to the acoustic transfer characteristic measuring apparatus 2 of the present embodiment, the same effect as that of the first embodiment can be obtained without calculating the spatio-temporal frequency region. The various processes described above are not only executed in time series according to the description, but may also be executed in parallel or individually as required by the processing capability of the apparatus that executes the processes. Needless to say, other modifications are possible without departing from the spirit of the present invention.

  Further, when the above-described configuration is realized by a computer, processing contents of functions that each device should have are described by a program. The processing functions are realized on the computer by executing the program on the computer.

  The program describing the processing contents can be recorded on a computer-readable recording medium. As the computer-readable recording medium, for example, any recording medium such as a magnetic recording device, an optical disk, a magneto-optical recording medium, and a semiconductor memory may be used.

  The program is distributed by selling, transferring, or lending a portable recording medium such as a DVD or CD-ROM in which the program is recorded. Furthermore, the program may be distributed by storing the program in a storage device of the server computer and transferring the program from the server computer to another computer via a network.

  A computer that executes such a program first stores, for example, a program recorded on a portable recording medium or a program transferred from a server computer in its own storage device. When executing the process, the computer reads a program stored in its own recording medium and executes a process according to the read program. As another execution form of the program, the computer may directly read the program from a portable recording medium and execute processing according to the program, and the program is transferred from the server computer to the computer. Each time, the processing according to the received program may be executed sequentially. Also, the program is not transferred from the server computer to the computer, and the above-described processing is executed by a so-called ASP (Application Service Provider) type service that realizes the processing function only by the execution instruction and result acquisition. It is good. Note that the program in this embodiment includes information that is used for processing by an electronic computer and that conforms to the program (data that is not a direct command to the computer but has a property that defines the processing of the computer).

  In this embodiment, the present apparatus is configured by executing a predetermined program on a computer. However, at least a part of these processing contents may be realized by hardware.

Claims (8)

A speaker array in which a plurality of speakers are arranged in a straight line;
A microphone array in which a plurality of microphones are linearly arranged;
An STSP signal calculation unit that calculates a spatio-temporal region STSP signal that is a representation of the spatio-temporal region of the STSP signal that is a signal in which the angle and frequency of the plane wave at the time of synthesis change in the time direction, and outputs from the speaker array;
An inverse STSP signal calculator for calculating a spatiotemporal domain inverse STSP signal based on the spatiotemporal domain STSP signal;
An input signal that is a signal picked up by the microphone array, and a transfer characteristic estimated value calculation unit that calculates an estimated value of the spatiotemporal acoustic transfer characteristic based on the spatiotemporal domain inverse STSP signal;
An acoustic transfer characteristic measuring apparatus including: The acoustic transfer characteristic measuring device according to claim 1,
Δω is a parameter for adjusting the increase amount of the temporal frequency, Δk _x is a parameter for adjusting the increase amount of the spatial frequency, ω ₀ is a parameter for adjusting the initial value of the temporal frequency, and k _x0 is an initial value of the spatial frequency. As parameters to be adjusted, i and j indicate indexes in the spatial direction (speaker direction) x _i and time direction t _j , N _x is the number of speakers and microphones, N _t is the signal length in the time direction,
The STSP signal calculator calculates a spatio-temporal region STSP signal.

Calculate as
The inverse STSP signal calculation unit calculates a space-time domain inverse STSP signal.

Sound transfer characteristic measuring device that calculates as A speaker array in which a plurality of speakers are arranged in a straight line;
A microphone array in which a plurality of microphones are linearly arranged;
A spatio-temporal frequency domain STSP signal, which is a representation of the spatio-temporal frequency domain of the STSP signal, which is a signal in which the angle and frequency of the plane wave at the time of synthesis change in the time direction, is calculated under the condition that the temporal frequency and the spatial frequency change linearly. A spatio-temporal frequency domain STSP signal calculator,
A spatio-temporal region STSP signal calculator that calculates a spatio-temporal region STSP signal that is a representation of the spatio-temporal region of the STSP signal based on the spatio-temporal frequency region STSP signal, and outputs the spatio-temporal region STSP signal from the speaker array;
A spatio-temporal frequency domain inverse STSP signal calculation unit for calculating a spatio-temporal frequency domain inverse STSP signal, which is a signal for generating a pulse signal by convolution with the spatio-temporal frequency domain STSP signal;
A spatio-temporal domain inverse STSP signal calculator that calculates a spatio-temporal domain inverse STSP signal based on the spatio-temporal frequency domain inverse STSP signal;
An input signal that is a signal picked up by the microphone array, and a transfer characteristic estimated value calculation unit that calculates an estimated value of the spatiotemporal acoustic transfer characteristic based on the spatiotemporal domain inverse STSP signal;
An acoustic transfer characteristic measuring apparatus including: The acoustic transfer characteristic measuring device according to claim 3,
The spatio-temporal frequency domain STSP signal calculator is
k _{x, n} is the spatial frequency, ω _m is the time frequency _{, n is} the index of the spatial frequency k _{x, n} , m is the index of the time frequency ω _m , and Δω is a parameter that adjusts the amount of increase of the time frequency. , Δk _x is a parameter for adjusting the increase amount of the spatial frequency, ω ₀ is a parameter for adjusting the initial value of the temporal frequency, k _x0 is a parameter for adjusting the initial value of the spatial frequency, and the spatio-temporal frequency domain STSP signal The

Sound transfer characteristic measuring device that calculates as The acoustic transfer characteristic measuring device according to any one of claims 1 to 4,
The transfer characteristic estimated value calculation unit
An acoustic transfer characteristic measuring apparatus that calculates an estimated value of a spatio-temporal acoustic transfer characteristic by any one of a method using a two-dimensional circular convolution, a method using a two-dimensional linear convolution, and a method combining a circular convolution and a linear convolution. An acoustic transfer characteristic measurement method using a speaker array in which a plurality of speakers are linearly arranged and a microphone array in which a plurality of microphones are linearly arranged,
An STSP signal calculation step of calculating a spatio-temporal region STSP signal that is a representation of the spatio-temporal region of the STSP signal that is a signal in which the angle and frequency of the plane wave at the time of synthesis change in the time direction, and outputting from the speaker array;
An inverse STSP signal calculation step of calculating a spatiotemporal domain inverse STSP signal based on the spatiotemporal domain STSP signal;
A transfer characteristic estimated value calculating step for calculating an estimated value of a spatiotemporal acoustic transfer characteristic based on the input signal that is a signal collected by the microphone array and the spatiotemporal domain inverse STSP signal;
A method for measuring acoustic transfer characteristics including: An acoustic transfer characteristic measurement method using a speaker array in which a plurality of speakers are linearly arranged and a microphone array in which a plurality of microphones are linearly arranged,
A spatio-temporal frequency domain STSP signal, which is a representation of the spatio-temporal frequency domain of the STSP signal, which is a signal in which the angle and frequency of the plane wave at the time of synthesis change in the time direction, is calculated under the condition that the temporal frequency and the spatial frequency change linearly. A spatio-temporal frequency domain STSP signal calculation step;
A spatio-temporal region STSP signal calculation step of calculating a spatio-temporal region STSP signal, which is a representation of the spatio-temporal region of the STSP signal, based on the spatio-temporal frequency region STSP signal and outputting from the speaker array;
A spatio-temporal frequency domain inverse STSP signal calculation step of calculating a spatio-temporal frequency domain inverse STSP signal that is a signal that generates a pulse signal by convolution with the spatio-temporal frequency domain STSP signal;
A spatio-temporal domain inverse STSP signal calculation step of calculating a spatio-temporal domain inverse STSP signal based on the spatio-temporal frequency domain inverse STSP signal;
A transfer characteristic estimated value calculating step for calculating an estimated value of a spatiotemporal acoustic transfer characteristic based on the input signal that is a signal collected by the microphone array and the spatiotemporal domain inverse STSP signal;
A method for measuring acoustic transfer characteristics including:   A program for causing a computer to function as the acoustic transfer characteristic measuring device according to any one of claims 1 to 5.

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