TW201800774A - Method and apparatus for space status detection based on acoustic chirp signals - Google Patents

Abstract

A method and an apparatus for space status detection based on acoustic chirp signals are provided. The method includes following steps. One of a plurality of acoustic chirp signals is transmitted into a space at a plurality of different time points respectively. A plurality of varied acoustic waves that are the transmitted acoustic chirp signals have varied in the space are received sequentially to generate a plurality of space-response acoustic signals, and a plurality of space status features are generated according to the space-response acoustic signals. Therefore, changes of the space status are detected according to a comparison of two of the space status features.

Description

Method and device for detecting spatial disturbance based on frequency modulated sound wave

The disclosure relates to a spatial state detecting device, and in particular to a method and device for detecting spatial disturbance based on frequency modulated sound waves.

Due to the rapid development of technology and the increasing demand for living standards, smart families have become a trend in recent years. In the application of existing smart homes, taking home security and security care as an example, it is possible to determine the events that may occur in the space through the sensing network and sensing information analysis to achieve the function of security monitoring.

In general, the cost of hardware devices in a security monitoring system is usually costly, and the procurement cost is one of the important considerations for general users. Therefore, how to reduce the hardware cost of the security monitoring/detection device has become one of the important topics in the development of related technologies.

In addition, since the real environment is full of environmental noise (such as broadband, time-varying sound signals), spatial disturbance detection techniques using sound waves to create a starting space model may take time and may be caused by mixed background noise of the measurement signals. The detection results are affected, so the interference of environmental noise has become one of the factors to consider.

The disclosure provides a method and device for detecting spatial disturbance based on frequency modulated sound waves, which can reduce the cost of the detecting device, reduce the problem of signal dead angle and signal transmission and directivity, and reduce the correlation between spatial response sound waves and background noise.

The method for detecting a spatial disturbance based on an FM sound wave of an embodiment of the present disclosure includes the following steps. One of the plurality of FM sound waves is transmitted in the space at different time points. The plurality of sound waves whose frequency modulated sound waves are changed in space are sequentially received to generate a plurality of spatially responsive sound wave signals, and a plurality of spatial state characteristic parameters of the space are obtained according to the spatial response sound wave signals. The change in spatial state is detected by comparing two of these spatial state characteristic parameters.

The FM sound-based spatial disturbance detecting apparatus of the embodiment of the present disclosure includes a receiving device, a processing unit, and a decision unit. The receiving device is configured to sequentially receive a plurality of sound waves whose frequency is changed in a plurality of frequency modulated sound waves to generate a plurality of spatially responsive sound wave signals, wherein each of the frequency modulated sound waves is respectively sent to the space at different time points in. The processing unit is coupled to the receiving device to receive the spatial response acoustic signals, and calculates a plurality of spatial state characteristic parameters of the space according to the spatial response acoustic signals. The decision unit is coupled to the processing unit to receive the spatial state feature parameters and to detect a change in the spatial state by comparing two of the spatial state feature parameters.

Based on the above, the present disclosure proposes a method and apparatus for detecting spatial disturbance based on frequency modulated sound waves. By sequentially transmitting the frequency modulated sound waves in the space at different time points, the plurality of sound waves that are changed in the spatially modulated sound waves are sequentially received to generate a plurality of spatially responsive sound wave signals, and the sound waves are responded according to the spatial waves. The signal acquires multiple spatial state feature parameters of the space. The change in spatial state is detected by comparing two of these spatial state characteristic parameters. Since the present disclosure uses sound as a sensing medium, a general full-range speaker (horn) and a microphone can be used as the sound transmitting and receiving device. In this way, the cost of the detecting device can be reduced, and since the sound wave can be received by multiple reflections in space (especially indoor space), the problem of signal dead angle and signal transmission and directivity can also be reduced. In addition, the content of the disclosure is to compare the spatial state characteristic parameters of the spatially responsive sound waves received at different time points, and can be detected without the modeling time being started, and can effectively reduce the correlation between spatial response sound waves and background noise. Sex.

The above described features and advantages of the invention will be apparent from the following description.

The exemplary embodiments of the present disclosure will now be described in detail, and examples of the exemplary embodiments are illustrated in the drawings. In addition, wherever possible, the same reference numerals in the drawings The directional terms mentioned in the following embodiments, such as up, down, left, right, front or back, etc., are only directions referring to the additional drawings. Therefore, the directional terminology used is for the purpose of illustration and not limitation.

FIG. 1 is a block diagram showing a spatial disturbance detecting apparatus based on an FM sound wave according to an embodiment of the present disclosure. Referring to FIG. 1, the spatial disturbance detecting device 100 based on the FM sound wave is used to detect a state change in a space, such as a person moving or moving in and out of the space. In the present embodiment, the spatial disturbance detecting apparatus 100 includes a receiving apparatus 110, a processing unit 120, a decision unit 130, a storage unit 140, and a transmitting apparatus 150. The transmitting device 150 is configured to repeatedly send the frequency modulated sound wave ACS in a space (not shown) at a plurality of different time points, and the sending interval time of the time point may be a fixed value or a change value, for example, the transmitting device. The frequency modulated acoustic wave ACS can be transmitted periodically or randomly, and the disclosure does not limit this. The receiving device 110 is configured to sequentially receive the sound wave ARW (hereinafter referred to as a spatial response sound wave ARW) which is changed in the above-mentioned spatially modulated sound wave ACS, and convert each received spatial response sound wave ARW into space one by one. In response to the acoustic signal ARS, the change in the above space is, for example, that the frequency modulated acoustic wave ACS is reflected in space. The processing unit 120 is coupled to the receiving device 110 to receive the spatial response acoustic signals ARS, and according to the plurality of spatial state characteristic parameters SCP of the spatial response acoustic wave signal ARS, the determining unit 130 is coupled to the processing unit 120 to receive the spatial states. The feature parameter SCP, and detecting the change of the spatial state by comparing two of the spatial state feature parameters SCP, for example, the decision unit 130 can detect the spatial state by comparing the two spatial state feature parameters SCP obtained continuously. The change, that is to say the decision unit 130, can detect the change of the spatial state by comparing the currently received spatial state feature parameter SCP with the next or previous received spatial state feature parameter SCP. The storage unit 140 stores a plurality of FM audio data ACDs and is coupled to the processing unit 120.

It should be noted that, in other embodiments, the spatial disturbance detecting apparatus 100 may not include the storage unit 140 and/or the transmitting apparatus 150, and those skilled in the art may appropriately select according to actual needs or designs. There is no limit to this.

In this embodiment, the transmitting device 150 may be a speaker, such as a full-range speaker, instead of a special-sized tweeter. In addition, the transmitting device 150 may be coupled to the storage unit 140, for example. The storage unit 140 stores a plurality of FM audio data ACD, so the transmitting device 150 can transmit a plurality of FM sound waves ACS in the space according to at least one of the FM audio data ACD in the storage unit 140. The receiving device 110 may be a microphone, such as an omnidirectional microphone device, although the disclosure is not limited thereto. Any component that can emit sound and receive sound can be used as the receiving device 110 and the transmitting device 150 in the embodiment of the disclosure, respectively. In addition, the receiving device 110 and the transmitting device 150 may be configured in the same device, or may be configured in different locations in separate locations, and the disclosure is not limited thereto.

In this embodiment, the present disclosure can use a speaker (speaker) and a microphone configured in a general household or electronic device as a transmitting and receiving device for the pulse sound, and the device cost can be effectively reduced. In addition, since sound waves can be received by multiple reflections in the indoor space, the problem of signal dead angle and signal transmission and reception directivity is also reduced.

In this embodiment, the processing unit 120 and the decision unit 130 may be hardware, firmware, or software or machine executable code stored in the memory and loaded by the processor or the microprocessor. However, if a hardware or a circuit is used, each unit may be completed by an individual circuit chip, or may be partially or entirely realized by a single integrated circuit chip, but is not limited thereto. The memory may be, for example, a compact disc, a random access memory, a read only memory, a flash memory, a floppy disk, a hard disk, or a magnetic optical disk, or may be downloaded from a network to be stored in a remote recording medium or Non-temporary machines can read media and will store the recording medium in the area. The above hardware can be implemented using, for example, a general-purpose computer, an special function integrated circuit (ASIC), or a programmable logic gate array (FPGA). The hardware may include a memory element when the hardware is accessed and the software or machine executable code is executed. The memory component is, for example, a random access memory, a read only memory, a flash memory, a thumb disc, etc., and can be used to store or receive the above software or machine executable code.

Please refer to FIG. 2A. FIG. 2A is a timing diagram of frequency-modulated sound waves according to an embodiment of the present disclosure. In this embodiment, the frequency modulated sound wave ACS sent by the transmitting device 150 can be a pulse sound, and the duration is, for example, 7.5 milliseconds (ms). It is worth mentioning that the frequency modulated sound wave ACS can be audible. The sound wave, wherein the audible sound wave has a frequency range of about 20 Hz to 20 kHz, and in one embodiment, the frequency of the frequency modulated sound wave ACS falls within the range of 9 kHz (9 kHz) to 1 8 kHz (18 kHz). In the frequency band interval 202 of the frequency modulated acoustic wave ACS, the maximum frequency is called the upper bound of the frequency band, and the minimum value of the frequency is called the lower bound of the frequency band. The frequency of the frequency modulated acoustic wave ACS continuously changes with time in the range of the upper boundary of the frequency band and the lower bound of the frequency band, as shown in FIG. 2A. Shown. In other embodiments, the frequency of the frequency modulated acoustic wave ACS may also monotonically rise from the lower bound of the frequency band to the upper bound of the frequency band in the frequency band interval 202, or monotonically decrease from the upper bound of the frequency band to the lower bound of the frequency band. In addition, the frequency-modulated sound wave ACS may be a composite frequency-modulated sound wave composed of a plurality of frequency bands. Referring to the embodiment of FIG. 2B, FIG. 2B illustrates a time-frequency diagram of the composite frequency-modulated sound wave according to an embodiment of the present disclosure. The frequency modulated sound wave ACS is a composite frequency modulated sound wave that is superimposed by a frequency band 204 and a frequency band 206. The disclosure does not limit this.

In this embodiment, the present disclosure uses a higher frequency, narrower frequency (9 kHz - 18 kHz) excitation signal, can use a lower sound pressure as an excitation source, and by increasing the frequency, a narrow frequency band, through Increasing the variation of the excitation source in a short time and improving the variability of the spatial response sound wave can effectively reduce the correlation between the spatial response sound wave and the background noise.

In addition, the space configured by the spatial disturbance detecting device 100 may be an indoor space, and the spatial response sound wave ARW received by the receiving device 110 may be a pulse sound response sound wave (Impulse Response) in which the pulse sound responds to the space, for example, Corresponding reverberation sound waves are generated by the reflection of sound waves in space and objects, ground, walls and roofs in space, but the disclosure is not limited to changes in space. It should be noted that the spatial response sound wave ARW will vary with the size of the indoor space and the layout. For example, it is shown in FIG. 3A to FIG. 3B. FIG. 3A is a time-frequency diagram of an indoor spatial response sound wave of an open room according to an embodiment of the present disclosure. FIG. 3B is a time-frequency diagram of an indoor spatial response sound wave having an item or a person in a room in an embodiment of the present disclosure. FIG. As can be seen from FIG. 3A to FIG. 3B, the impulse response of the pulse sound in the indoor space varies with the size of the indoor space and the change of articles or personnel in the space. Therefore, the characteristics of the spatial response sound wave ARW can reflect the state characteristics of the indoor space, and the spatial response sound wave signal ARS is the electronic signal after the spatial response sound wave ARW conversion.

In an embodiment, the ambient background noise is broadband and varies slowly with time, so the residual difference value at the near time point is not large, but when the person moves in space or other events cause the spatial state to change drastically, the similarity The reverberation sample difference value at the time point is much larger than the reverberation difference value caused by the ambient background noise, so an embodiment of the present disclosure detects by comparing two of the spatial state characteristic parameters SCP corresponding to different time points. The change of the space state can resist the full-frequency noise in the external environment, effectively reduce the correlation between the background noise and the spatial response sound wave, and the reaction time is fast, and the detection time can be detected after the modeling time is started, thereby improving the use efficiency.

4 is a block diagram of a processing unit illustrated in the embodiment of FIG. 1 in accordance with the disclosure. The processing unit 120 includes a signal extraction unit 210 and a calculation unit 220. The signal acquisition unit 210 receives the spatial response acoustic wave signal ARS from the receiving device 110, and captures the effective signal ES in the spatial response acoustic wave signal ARS. The computing unit 220 is coupled to the signal capturing unit 210 to receive the valid signal ES, and generates a corresponding spatial state characteristic parameter SCP according to the valid signal ES.

In an embodiment, in order to improve the calculation efficiency of the computing unit 220, the signal capturing unit 210 may only capture the valid signal ES in the spatial response acoustic signal ARS. The signal capturing unit 210 includes a filtering unit 212 and a first capturing unit 214. The filtering unit 212 is coupled to the receiving device 110 to receive the spatial response acoustic signal ARS, and filters the spatially responsive acoustic signal ARS. The filtering unit 212 is, for example, a bandpass filter, or other similar components having a filtering function, and those skilled in the art can appropriately change according to the needs, and the disclosure does not limit this. The first capturing unit 214 is coupled to the filtering unit 212, receives the filtered spatial response acoustic wave signal ARS', and then extracts the effective signal ES from the filtered spatial response acoustic wave signal ARS'.

For ease of description, the following disclosure uses an example of a spatially responsive acoustic wave as an example to illustrate an embodiment of extracting a valid signal ES from a filtered spatially responsive acoustic wave signal ARS'. Referring to FIG. 5A and FIG. 5B, FIG. 5A is an energy distribution diagram of spatially responsive sound waves according to an embodiment of the disclosure, and FIG. 5B is a spatially responsive sound wave corresponding to the embodiment of FIG. 5A.

The first capturing unit 214 first divides the filtered spatial response acoustic wave signal ARS' into a plurality of frames and calculates feature data of the sound boxes, wherein the feature data includes energy distribution of each sound frame, energy The calculation may be the sum of the squared values of all the signal amplitudes in the audio frame. As shown in FIG. 5A, the receiving device 120 successively receives several spatially responsive acoustic wave signals ARS, corresponding to the sound boxes 501, 502, 503 to 50N, According to the energy distribution data in the sound boxes (the sound boxes 501, 502, 503 to 50N), for example, the starting point of each of the sound boxes can be determined by the local energy maximum value finding method, that is, the different time points are compared. The amount of energy received is taken as the starting point in each of the sound boxes at a time point corresponding to the maximum energy value. It should be noted that the disclosure does not limit the decision criteria or the screening method of the starting point.

The first capturing unit 214 can extract the required response sample segment from the filtered spatial response acoustic wave signal ARS' according to the comparison result of the characteristic data (for example, the energy size comparison result) and the transmission interval time of the FM acoustic wave ACS. . Please refer to FIG. 5B. Taking the sound box 501 as an example, in the present embodiment, if the transmission time interval between the frequency-modulated sound wave ACS corresponding to the sound box 501 and the frequency-modulated sound wave ACS corresponding to the next sound box 502 is 0.5 seconds, the first capturing unit 214 Taking the maximum energy 値 in the sound box 501 as a starting point, a signal within 0.5 seconds (that is, the above-mentioned transmission time interval) is drawn backward as a response sample section of the sound box 501. In another embodiment, the signal capturing unit 210 may not include the filtering unit 212. The first capturing unit 214 first divides the spatial response acoustic wave signal ARS into a plurality of frames and calculates feature data of the sound frames. Then, according to the comparison result of the characteristic data (for example, the energy size comparison result) and the transmission interval time of the FM sound wave ACS, the required response sample segment is extracted from the spatial response acoustic wave signal ARS.

For further explanation, please refer to FIG. 6. FIG. 6 is a response sample segment corresponding to the embodiment of FIG. 5B. The response sample section includes a Direct sound section 610, Reflection sections 620 and 630 (Early Reflections section 620 and late reflection section 630) And background noise of 640. The direct sound indicates that the signal is not spatially reflected, the energy loss is the smallest, and thus has a large amplitude, and the reflected sound represents a signal that is reflected once or multiple times. In an embodiment, the first capture unit 214 filters out the direct sound segment 610 of the response sample segment or the noise to obtain the valid signal ES.

When the positions of the receiving device 110 and the transmitting device 150 are known, the time required for the frequency modulated sound wave ACS from the transmitting device 150 to the receiving device 110 can be derived as the predetermined time T. In an embodiment, the first capturing unit 214 A segment of the beginning of the response sample segment that is less than the predetermined time T is filtered to filter out the direct tone segment 610. In other embodiments, the first capturing unit 214 may also determine, according to whether the absolute value of the amplitude value of the response sample segment continues to be less than the average amplitude value of the response sample segment or the first set amplitude value for the first predetermined time T1, The signal before this first predetermined time T1 is identified as the direct tone section 610 and is removed. The disclosure does not limit the way in which the direct sound segment is identified, depending on the actual design/application requirements.

In this embodiment, the first capturing unit 214 may further filter the background noise 640 or the partial multiple reflection sound segment 630 of the response sample segment to reduce the computational burden of the computing unit 220. For example, the first capturing unit 214 may filter the signal after responding to the sample segment by 7.5 milliseconds (or plus a buffering time) according to the duration of the frequency modulated sound wave ACS, for example, 7.5 milliseconds, or The first capturing unit 214 may determine, according to whether the absolute value of the amplitude value of the response sample segment continues to be less than the average amplitude value or the second set amplitude value of the response sample segment for a second predetermined time T2, after the second predetermined time T2 The sound sensing signal filtering is not limited by the screening conditions for filtering the background noise 640 or the partial multiple reflection sound section 630, depending on the actual design/application requirements.

In this embodiment, after the first capturing unit 214 filters out the direct sound section 610, the background noise 640, and/or the partial multiple reflection sound section 630, the valid section 650 captured is the effective signal ES. In another embodiment, the first capturing unit 214 filters out the direct sound section 610 and is the effective signal ES; in another embodiment, the first capturing unit 214 filters out the direct sound section 610 and the background noise. After 640 is a valid signal ES. However, the disclosure is not limited thereto, and it is decided to filter which sections of the response sample section are filtered depending on actual design/application requirements.

Referring to FIG. 1 and FIG. 4 again, in this embodiment, the computing unit 220 receives the FM audio data ACD corresponding to the valid signal ES from the storage unit 140, wherein the valid signal ES is a space changed from the frequency modulated acoustic wave ACS in space. The frequency modulated sound wave ACS is transmitted by the transmitting device 150 according to the above-mentioned FM audio data ACD. The calculating unit 220 can obtain the spectogram data of the corresponding frequency-accurate sound wave ACS after being converted into a temporal-spectral domain according to the FM audio data ACD; in an embodiment, the calculating unit 220 can obtain the storage unit 140 from the storage unit 140. The audio data ACD is received and the audio data ACD is converted to the time-frequency domain to obtain time-frequency data, such as shown in FIG. 2A and FIG. 2B. The calculating unit 220 receives the valid signal ES from the first capturing unit 214 and converts the effective signal ES into time-frequency data. The frequency-modulated acoustic wave ACS and the effective signal ES can obtain time-frequency data by Fourier transform (for example, two-dimensional fast Fourier transform (FFT)).

Please refer to FIG. 7. FIG. 7 is a time-frequency diagram of the frequency modulated audio data and the effective signal according to an embodiment of the disclosure. In this embodiment, the FM audio time-frequency data 710 is time-frequency data corresponding to the FM sound wave ACS, for example, the time-frequency data after the corresponding audio data ACD is converted to the time-frequency domain or from the ACD corresponding to the FM audio data. The frequency modulated sound wave ACS is converted to the time-frequency data in the time-frequency domain, and the effective signal time-frequency data 720 is the result of the effective signal ES being converted to the time-frequency domain. The calculating unit 220 may firstly convert the valid signal time-frequency data 720 and the frequency-modulated audio time-frequency data. The 710 performs the comparison, and then extracts the time-frequency block corresponding to the FM audio time-frequency data 710 from the valid signal time-frequency data 720 as a comparison result, such as the time-frequency block 722, 724, 726 or 72N, and then the above-mentioned time The frequency block is matched with the FM audio time-frequency data 710, and the similarity between the two is calculated, which can be used as the spatial state feature parameter SCP. In other words, the computing unit 220 will time-frequency blocks 722, 724. The 726 or 72N performs a convolution operation with the FM audio time-frequency data 710, and the result is the spatial state characteristic parameter SCP.

FIG. 8 is a time-frequency diagram of frequency modulated audio data and an effective signal according to another embodiment of the disclosure. The implementation method and principle are similar to the embodiment of FIG. 7. No further details are provided herein. In the embodiment of FIG. 8, the FM acoustic wave ACS is transmitted according to the composite FM audio data, and the FM audio time-frequency data 730 is composed of two sets of FM audio. Time-frequency data 732 and 734 are combined. The calculating unit 220 can compare the valid signal time-frequency data 760 with the FM audio time-frequency data 732, 734, and then extract the time-frequency block 742 corresponding to the FM audio time-frequency data 732 from the valid signal time-frequency data 760, 744, 746 or 74N, and the time-frequency block 752, 754, 756 or 75N corresponding to the FM audio time-frequency data 734 are used as a comparison result, and a matching action is performed to calculate the spatial state feature parameter SCP.

Please refer to FIG. 1 and FIG. 9. FIG. 9 is a schematic diagram of spatial state feature parameters sequentially obtained by comparison according to an embodiment of the disclosure. In the present embodiment, the receiving device 110 receives the spatial response acoustic wave signals ARS at four different but adjacent time points, and then the corresponding spatial state characteristic parameters 910, 920, 930, 940 are calculated by the processing unit 120. The spatial state feature parameters 910, 920, 930, 940 represent spatial states measured at four different but consecutive time points, respectively, wherein the spatial state feature parameters 910, 920, 930, 940 are in the positive horizontal axis and the negative horizontal direction. The results of the axes are shown as two left and right views. The spatial state feature parameters 910, 920, 930, and 940 shown in FIG. 9 are only examples, and are not intended to limit the disclosure. The decision unit 130 receives the spatial state feature parameters 910, 920, 930, 940 from the processing unit 120, and calculates the difference data between the previous or subsequent spatial state feature parameters, and then calculates the difference parameter S1 based on the difference data. , S2 and S3. Specifically, the spatial state feature parameter 920 subtracts the previous received spatial state feature parameter 910 to obtain the difference data, and the difference data may be array data, and then the difference parameter S1 is calculated according to the difference data; The next spatial state feature parameter 930 received after the state feature parameter 920 subtracts the spatial state feature parameter 920 to obtain the difference data, and then calculates the difference parameter S2 based on the difference data; the spatial state feature parameter 940 is subtracted from the space. The spatial state feature parameter 930 received before the state feature parameter 940 obtains the difference data, and then calculates the difference parameter S3 based on the difference data. The method for calculating the difference parameter based on the difference data is, for example, a 2-norm (2-norm) operation or other operation method, and the disclosure does not limit the method for calculating the difference parameter.

Please refer to FIG. 10 , which is a histogram of spatial state comparison results according to an embodiment of the disclosure. The decision unit 130 can detect whether the spatial state changes according to the calculated difference parameter (for example, the difference parameters S1, S2, and S3 of the embodiment of FIG. 9) and the threshold value ST. The threshold value ST can be a preset value or determined according to the previous spatial state or according to other conditions, and the disclosure is not limited thereto. The decision unit 130 compares the difference parameter with the threshold value ST. When the difference parameter is greater than the threshold value ST, the spatial state may be changed. Otherwise, the normal state is indicated, and no disturbance event occurs in the detected space, for example, Someone goes in or out.

Therefore, in this embodiment, by receiving the frequency-modulated sound wave periodically or randomly transmitted, the spatial response sound wave is changed in space, and the spatial state characteristic parameter of the space is obtained according to the spatial response sound wave, and the comparison is performed. The spatial state characteristic parameters of the spatial response sound waves received at different time points can detect the change of the spatial state, which can effectively reduce the correlation between the spatial response sound wave and the background noise, and thus can distinguish the home environment noise and space under the background noise. The difference in disturbance events (such as personnel entering and exiting).

Please refer to FIG. 11 . FIG. 11 is a flow chart of steps of a method for detecting spatial disturbance based on frequency modulated sound waves according to an embodiment of the present disclosure. The method for detecting spatial disturbance based on the frequency-modulated sound wave of the present embodiment is applicable to any of the embodiments of FIG. 1 to FIG. 10, and the method includes the following steps. First, in step S1120, one of the plurality of frequency-modulated sound waves is respectively transmitted in the space at different time points, wherein the transmission interval time of the time points may be a fixed value or a change value. Next, in step S1140, the plurality of sound waves whose frequency modulated sound waves are changed in space are sequentially received to generate a plurality of spatially responsive sound wave signals, and a plurality of spatial state characteristic parameters of the space are obtained according to the spatial response sound wave signals. Thereafter, in step S1160, the change in the spatial state is detected by comparing two of the spatial state characteristic parameters. In addition, the method for detecting spatial disturbance based on the FM sound wave of the present embodiment can obtain sufficient teaching, suggestion and implementation description from the description of the embodiment of FIG. 1 to FIG. 10, and therefore will not be described again.

Please refer to FIG. 12 . FIG. 12 is a flow chart of steps of a method for detecting spatial disturbance based on frequency modulated sound waves according to another embodiment of the disclosure. The method for detecting spatial disturbance based on the frequency-modulated sound wave of the present embodiment is applicable to any of the embodiments of FIG. 1 to FIG. 10, and includes the following steps. First, in step S1210, one of a plurality of frequency-modulated sound waves is transmitted in the space at different time points. For example, the first frequency modulated sound wave is transmitted at the first time point, the second frequency modulated sound wave is transmitted at the second time point, and so on. Next, in step S1212, the plurality of sound waves whose frequency modulated sound waves are changed in space are sequentially received to generate a plurality of spatially responsive sound wave signals. For example, receiving the first frequency modulated sound wave in the spatially changed sound wave to generate the first spatially responsive sound wave signal; receiving the second frequency modulated sound wave in the spatially changed sound wave to generate the second spatially responsive sound wave signal, and so on. In step S1214, corresponding response sample segments are retrieved from each spatially responsive sound wave signal. For example, the corresponding first response sample segment is extracted from the first spatially responsive acoustic signal; the corresponding second response sample segment is extracted from the second spatially responsive acoustic signal, and so on. In step S1216, the direct sound segment or noise of the response sample segment is filtered to obtain a valid signal. For example, filtering the direct sound segment or noise of the first response sample segment to obtain the first valid signal; filtering out the direct sound segment or noise of the second response sample segment to obtain the second valid signal, and so on. . In step S1218, the valid signal and the FM audio data corresponding to the FM sound wave are compared. For example, comparing the first valid signal with the first FM audio data corresponding to the first FM sound wave; comparing the second valid signal with the second FM audio data corresponding to the second FM sound wave, and so on, wherein the first FM audio signal The data and the second FM audio material are, for example, the same FM audio material. In step S1220, the spatial state feature parameter is generated according to the comparison result, for example, the first spatial state feature parameter is generated according to the comparison result of the first valid signal and the first FM audio data; and the second valid signal and the second FM audio signal are generated according to the second valid signal. The alignment result of the data produces a second spatial state characteristic parameter; and so on. In step S1222, it is determined whether a plurality of spatial state feature parameters corresponding to different time points are obtained, for example, determining whether to obtain a second spatial state feature parameter corresponding to a time point different from the first spatial state feature parameter, and if the result is yes, Go to step S1224, and if the result is no, return to step S1212 to obtain another spatial response sound wave signal. For example, the second spatial state parameter may be the next spatial state parameter obtained after the first spatial state parameter. . Next, in step S1224, the difference parameter is calculated according to the difference data between two of the plurality of spatial state feature parameters corresponding to different time points, for example, according to the first spatial state feature parameter and the second spatial state feature parameter The difference data between the calculations calculates the difference parameter. In step S1226, it is determined whether the difference parameter is greater than a threshold. The threshold value may be preset or float according to different conditions. When the difference parameter is greater than the threshold, the process proceeds to step S1228 to determine that the spatial state changes, when the difference parameter If it is smaller than the threshold, the process proceeds to step S1230, and it is judged that the spatial state remains unchanged.

In addition, the method for detecting spatial disturbance based on the FM sound wave of the present embodiment can obtain sufficient teaching, suggestion and implementation description from the description of the embodiment of FIG. 1 to FIG. 10, and therefore will not be described again.

In summary, the present disclosure proposes a method and apparatus for detecting spatial disturbance based on frequency modulated sound waves. Transmitting one of the plurality of frequency-modulated sound waves into the space at different time points, and then sequentially receiving the plurality of sound waves of the frequency-modulated sound waves in the space to generate a plurality of spatially-responsive sound wave signals, and A plurality of spatial state characteristic parameters of the space are obtained according to the spatial response acoustic signals. The change in spatial state is detected by comparing two of these spatial state characteristic parameters. Since the present disclosure uses FM sound waves as the sensing medium, a general full-range speaker (horn) and a microphone can be used as the sound transmitting and receiving device, thereby reducing the cost of the detecting device, and Sound waves can be received in multiple reflections in space (especially indoor spaces), thus also reducing the problem of signal dead angle and signal transceiving directivity. The disclosure uses FM tones, so the source of the stimuli changes in a short period of time, improving the variability of the reflected sound. In addition, the content of the disclosure is to compare the spatial state characteristic parameters of the spatially responsive sound waves received at different time points, and can be detected without the modeling time being started, and can effectively reduce the correlation between spatial response sound waves and background noise. Sexuality, improve the efficiency of use.

The present disclosure has been disclosed in the above embodiments, but it is not intended to limit the invention, and those skilled in the art can make some modifications and refinements without departing from the spirit and scope of the invention. Therefore, the scope of the invention is defined by the scope of the appended claims.

100‧‧‧ Spatial Disturbance Detection Device
110‧‧‧ receiving device
120‧‧‧Processing unit
130‧‧‧Decision unit
140‧‧‧ storage unit
150‧‧‧Send device
202, 204, 206‧‧‧ band interval
210‧‧‧Signal acquisition unit
212‧‧‧Filter unit
214‧‧‧First capture unit
220‧‧‧Computation unit
501, 502, 503, 50N‧‧‧ frames
610‧‧‧Direct sound section
620‧‧‧First reflection sound section
630‧‧‧Multiple reflections
640‧‧‧Background noise
650‧‧‧effective section
710, 730, 732, 734‧‧ ‧ FM audio time-frequency data
720, 760‧‧‧ Effective signal time-frequency data
722, 724, 726, 72N, 752, 754, 756, 75N‧‧‧ time-frequency blocks
910, 920, 930, 940‧‧‧ space state characteristic parameters
ACS‧‧‧FM sound waves
ACD‧‧‧ FM audio data
ARW‧‧‧Spatial Response Sound Wave
ARS‧‧‧ space response sound wave signal
ARS'‧‧‧Filtered spatial response acoustic signal
ES‧‧‧effective signal
SCP‧‧‧ Spatial State Characteristic Parameters
S1, S2 and S3‧‧‧ difference parameters
ST‧‧‧ threshold
S1120, S1140, S1160, S1210, S1212, S1214, S1216, S1218, S1220, S1222, S1224, S1226, S1228, S1230‧‧

The following drawings are a part of the specification of the disclosure, and illustrate the embodiments of the present disclosure, together with the description of the description. FIG. 1 is a block diagram showing a spatial disturbance detecting apparatus based on an FM sound wave according to an embodiment of the present disclosure. 2A is a time-frequency diagram of a frequency modulated sound wave according to an embodiment of the present disclosure. 2B is a timing diagram of a composite FM sound wave according to an embodiment of the present disclosure. FIG. 3A is a time-frequency diagram of an indoor spatial response sound wave of an open room according to an embodiment of the present disclosure. FIG. 3B is a time-frequency diagram of an indoor spatial response sound wave having an item or a person in a room in an embodiment of the present disclosure. FIG. 4 is a block diagram of a processing unit illustrated in the embodiment of FIG. 1 in accordance with the disclosure. FIG. 5A is a diagram showing energy distribution of spatially responsive sound waves according to an embodiment of the present disclosure. FIG. 5B is a spatially responsive sound wave corresponding to the embodiment of FIG. 5A. Figure 6 is a response sample section corresponding to the embodiment of Figure 5B. FIG. 7 is a time-frequency diagram of frequency modulated audio data and a valid signal according to an embodiment of the present disclosure. FIG. 8 is a time-frequency diagram of frequency modulated audio data and an effective signal according to another embodiment of the disclosure. FIG. 9 is a schematic diagram of spatial state feature parameters sequentially obtained by comparison according to an embodiment of the disclosure. FIG. 10 is a histogram of a spatial state comparison result according to an embodiment of the present disclosure. FIG. 11 is a flow chart showing the steps of a method for detecting a spatial disturbance based on a frequency modulated sound wave according to an embodiment of the present disclosure. FIG. 12 is a flow chart showing the steps of a method for detecting a spatial disturbance based on a frequency modulated sound wave according to another embodiment of the present disclosure.

S1120~S1160‧‧‧ steps of a method for detecting spatial disturbance based on frequency-modulated sound waves according to an embodiment of the present invention

Claims (25)

A spatial disturbance detection method based on frequency-modulated sound waves, comprising: transmitting one of a plurality of frequency-modulated sound waves in a space at different time points; sequentially receiving the frequency-modulated sound waves in the space a plurality of sound waves to generate a plurality of spatially responsive sound wave signals, and obtaining a plurality of spatial state characteristic parameters of the space according to the spatial response sound wave signals; and detecting the two by using two of the spatial state characteristic parameters Changes in the state of space. The method for detecting spatial disturbance based on frequency-modulated sound waves according to claim 1, wherein two of the spatial state characteristic parameters correspond to two spaces of adjacent two frequency-modulated sound waves of the frequency-modulated sound waves. State feature parameters. The method according to claim 1, wherein the step of obtaining the spatial state characteristic parameters of the space according to the spatial response acoustic signals comprises: extracting the spatial response sound waves a plurality of valid signals in the signal; and generating the spatial state characteristic parameters according to the valid signals. The method for detecting a spatial disturbance according to the third aspect of the invention, wherein the step of extracting the effective signals in the spatial response acoustic signals comprises: filtering the spatially responsive acoustic signals And cutting into a plurality of frames respectively; calculating a plurality of feature data of the sound frames, each of the feature materials including energy of the sound box corresponding to the sound boxes; and analyzing the feature data Take these valid signals. The method for detecting a spatial disturbance according to the fourth aspect of the invention, wherein the step of extracting the effective signals by analyzing the characteristic data comprises: comparing a comparison result of the characteristic data with The transmission interval of the frequency modulated sound waves is obtained from the spatial response sound wave signals, wherein each of the response sample segments includes a straight sound segment and a reflected sound segment, wherein the time is The transmission interval of a point is a certain value or a change value. The method for detecting a spatial disturbance based on the frequency modulated sound wave according to the fifth aspect of the invention, wherein the step of extracting the effective signals by analyzing the characteristic data further comprises: filtering out each of the response sample segments The direct sound segment or the noise to obtain the valid signals, wherein the step of filtering out the direct sound segments of each of the response sample segments comprises: filtering out the beginning of each of the response sample segments by less than a segment A section within a predetermined time. The method for detecting a spatial sound disturbance based on the frequency modulated sound wave according to claim 3, wherein the step of generating the spatial state characteristic parameters according to the effective signals comprises: according to the effective signals and corresponding to the A plurality of alignment results between at least one FM audio material of the frequency modulated sound wave to generate the spatial state characteristic parameters. The method for detecting a spatial disturbance based on the frequency-modulated sound wave according to claim 1, wherein the step of detecting the change of the spatial state by using two of the spatial state characteristic parameters includes: Calculating a difference parameter according to the difference data between the two of the spatial state characteristic parameters; and detecting whether the spatial state changes according to the difference parameter and a threshold. The method for detecting spatial disturbance based on frequency-modulated sound waves according to claim 1, wherein the frequency of the frequency-modulated sound waves continuously changes with time in a range from a lower boundary of a frequency band to an upper boundary of a frequency band. The method according to claim 1, wherein the frequency of the frequency modulated sound waves monotonically rises from a lower bound of a frequency band of the frequency band interval to an upper bound of a frequency band. The method for detecting spatial disturbance based on frequency-modulated sound waves according to claim 1, wherein in a frequency band interval, the frequency of the frequency-modulated sound waves monotonically decreases from a frequency band upper bound of the frequency band interval to a lower frequency band of a frequency band. The method for detecting spatial disturbance based on frequency-modulated sound waves according to claim 1, wherein the frequency-modulated sound waves are composite frequency-modulated sound waves combined by a plurality of frequency bands. The method for detecting spatial disturbance based on frequency-modulated sound waves according to claim 1, wherein the frequency of the frequency-modulated sound waves falls within a range of 9 kHz (9 kHz) to 18,000 kHz (18 kHz). The method for detecting spatial disturbance based on frequency-modulated sound waves according to claim 1, wherein the space is an indoor space, and the frequency-modulated sound waves are audible sound waves. A spatial disturbance detecting device based on a frequency-modulated sound wave, comprising: a receiving device, configured to sequentially receive a plurality of sound waves of a plurality of frequency-modulated sound waves in a space to generate a plurality of spatially-responsive sound wave signals, wherein each of the frequency-modulated sound waves The sound waves are respectively sent to the space at different time points; a processing unit is coupled to the receiving device to receive the spatially responsive sound wave signals, and calculate a plurality of spaces of the space according to the spatially responsive sound wave signals a state feature parameter; and a decision unit coupled to the processing unit to receive the spatial state feature parameters, and detecting the change of the spatial state by comparing two of the spatial state feature parameters. The spatial disturbance detection device based on the frequency-modulated acoustic wave according to claim 15, wherein two of the spatial state characteristic parameters that are compared by the decision unit correspond to two adjacent ones of the frequency-modulated sound waves. Two spatial state characteristic parameters of frequency modulated acoustic waves. The apparatus for detecting a spatial disturbance according to the fifteenth aspect of the invention, wherein the processing unit comprises: a signal acquisition unit for capturing a plurality of valid signals in the spatially responsive sound signals; A computing unit is coupled to the signal capturing unit to receive the valid signals, and generate the spatial state characteristic parameters according to the valid signals. The apparatus for detecting spatial disturbances based on the frequency-modulated sound wave according to claim 17, wherein the signal acquisition unit comprises: a filtering unit coupled to the receiving device to receive the spatially-resonant acoustic signals, and The spatially responsive acoustic wave signal is filtered; and a first capturing unit coupled to the filtering unit to receive the filtered spatially responsive acoustic wave signals, and then dividing the spatially responsive acoustic wave signals into a plurality of frames respectively And calculating a plurality of feature data of the sound boxes, and extracting the effective signals by analyzing the feature data, wherein each of the feature materials includes energy of the sound box corresponding to the sound boxes. The apparatus for detecting a spatial disturbance according to claim 18, wherein the first capturing unit filters out a continuous sound section or a noise of each of the plurality of response sample sections to obtain the The valid response signals, wherein the response sample segments are extracted from the spatially responsive sound wave signals according to a comparison result of the characteristic data and the transmission interval time of the frequency modulated sound waves, wherein each of the response sample segments includes The direct sound segment and a reflected sound segment, wherein the transmission interval time of the time points is a certain value or a change value, wherein the first capturing unit filters out the direct sound segment to filter out the responses The beginning of the sample segment is less than a segment within a predetermined time period. The modulating sound wave-based spatial disturbance detecting device of claim 15 further comprising: a storage unit coupled to the processing unit, the storage unit storing a plurality of frequency modulated audio data corresponding to the frequency modulated sound waves. The modulating sound wave-based spatial disturbance detecting device of claim 20, further comprising: a transmitting device coupled to the storage unit to receive at least one of the FM audio data, and according to the FM audio The data is sent to the FM sound waves in the space. The frequency-disturbed acoustic wave-based spatial disturbance detecting device according to claim 21, wherein the calculating unit receives the FM audio data corresponding to the frequency-modulated sound waves from the storage unit, and corresponding to the valid signals according to the effective signals The plurality of alignment results between the FM audio data of the FM sound waves generate the spatial state characteristic parameters. The method for detecting spatial disturbance based on frequency-modulated sound waves according to claim 21, wherein the frequency of the frequency-modulated sound waves transmitted by the transmitting device falls between 9 kHz (9 kHz) and 1 8.9 kHz (18 kHz). In the range. The method according to claim 21, wherein the transmitting device receives at least one of the FM audio data from the storage unit is at least two of the FM audio data. And combining to form a composite FM audio data, and transmitting the FM sound waves in the space according to the composite FM audio data. The spatial disturbance detecting apparatus based on the frequency-modulated sound wave according to claim 15, wherein the determining unit calculates a difference parameter according to the difference data between the two of the spatial state characteristic parameters, and according to the difference parameter, The difference parameter and a threshold detect whether the spatial state changes.