JP6085465B2 - Microphone array device - Google Patents

Description

  The present invention relates to a microphone array apparatus, and more particularly to a microphone array apparatus including a microphone unit (also referred to as a microphone module) that includes a microphone and can be freely arranged.

  There is known a microphone array in which a plurality of microphones are arranged along, for example, a plane or a curved surface and sound at a plurality of positions can be measured. Microphone arrays are used in many applications. For example, a microphone array is used to measure the sound pressure distribution of noise and may be used to improve the living environment. In addition, the microphone array is used, for example, as an ear of a robot, and may be used to identify a speaker and perform appropriate communication by performing sound source tracking and sound source separation based on sound data from the microphone array. .

  The invention of Patent Document 1 is a microphone array that can measure sound at a plurality of positions, and the microphones are slidably attached. Therefore, for each microphone, the distance from the sound source can be adjusted, and the sound pressure distribution of the sound source can be accurately measured.

JP 2005-91263 A

  However, in the invention of Patent Document 1, a plurality of microphones and amplifiers are connected one-to-one (see FIG. 1 of Patent Document 1). For this reason, at least as many cables as the number of microphones are required, and it is necessary to secure a cable space.

  Further, the connector portion of a component (amplifier in Patent Document 1) connected to a plurality of microphones increases in size as the number of microphones increases. For this reason, it has been difficult to downsize components connected to a plurality of microphones.

  The present invention has been made in view of such problems. According to some aspects of the present invention, there is provided a microphone array apparatus that can transfer audio data with a small number of cables even when the number of microphones is increased, and can be reduced in size.

(1) The present invention is a microphone array device, including a microphone, and first to Nth (N is an integer of 2 or more) microphone units that generate audio data based on an output signal of the microphone, and an analysis A control unit, wherein the Nth microphone unit outputs serial data including the audio data generated by the Nth microphone unit, and nth (n is an integer satisfying 1 ≦ n ≦ N−1). The microphone unit outputs serial data including the serial data received from the (n + 1) th microphone unit and the audio data generated by the nth microphone unit, and the analysis control unit outputs the first data The final stage serial data, which is serial data output from the microphone unit, is received and the final stage serial data is received. Included in, identifying each of said voice data of the microphone unit of the first to N.

  The microphone array apparatus of the present invention includes first to Nth microphone units and an analysis control unit. Here, N is an integer equal to or greater than 2, and the microphone array apparatus includes a plurality of microphone units.

  The plurality of microphone units can be freely arranged, and may be arranged in a planar shape with a regular shape, may be arranged on a curved surface, or may be arranged so that the interval changes randomly. Good. For example, a plurality of microphone units may be arranged to form a rectangle of A vertically and B horizontally (A and B are natural numbers satisfying A × B = N), or a polygon, circle, You may arrange | position so that an ellipse, a spiral shape, a cross shape, a three-dimensional shape, etc. may be comprised.

  The microphone unit includes a microphone and detects sound at the place where it is placed. The microphone may be a condenser microphone such as a dynamic microphone or an ECM, but a MEMS microphone that can be further downsized is preferable. The microphone unit generates sound data based on the output signal of the microphone. The audio data is a digital signal, and may be PCM (Pulse Code Modulation) data, for example.

  In the microphone array apparatus of the present invention, the first to Nth microphone units are connected in multiple stages. Each microphone unit generates new serial data obtained by adding its own audio data to the serial data received from the adjacent microphone unit, and outputs the new serial data to the adjacent microphone unit in the reverse direction. The own voice data may be added at the tail (the end of the received serial data) or may be added at the head (the beginning of the received serial data).

  Note that the Nth microphone unit farthest from the analysis control unit receives a predetermined fixed value instead of receiving serial data from the adjacent microphone unit. The predetermined fixed value may be “1” (high level of serial data) or “0” (low level of serial data), but the first to Nth microphone units are not operated. Set to a value different from the default value at the time (when serial data is not output). For example, when the first to Nth microphone units output “0” when not operating, the predetermined fixed value is “1”. Thus, the Nth microphone unit can recognize that it is a terminal microphone unit.

  The analysis control unit receives final stage serial data that is serial data output from the first microphone unit. The final stage serial data includes audio data of all (first to Nth) microphone units. And an analysis control part performs the process which identifies each audio | voice data of the 1st-Nth microphone unit.

  At this time, since the first to Nth microphone units generate audio data having the same number of bits (for example, m bits, m is a natural number), the analysis control unit only divides the audio data into m bits. It is possible to identify.

  According to the present invention, the first to Nth microphone units are connected in multiple stages, and serial data including audio data is output to the adjacent microphone unit. Therefore, even if the number of microphones (N) increases, the number of microphones decreases. Audio data can be transferred with a minimum of one cable. Therefore, the space for the cable can be reduced, and the size of the connector for connecting the cable can be reduced, thereby realizing a microphone array device that can be miniaturized.

(2) In this microphone array device, each of the first to Nth microphone units includes an audio data generation unit that generates the audio data by sampling the output signal of the microphone at a predetermined interval, The analysis control unit may adjust the predetermined interval of the audio data generation unit to be longer than a time required to receive the final stage serial data from the first microphone unit.

  According to the present invention, each of the first to Nth microphone units includes an audio data generation unit that generates audio data by sampling an output signal of the microphone at a predetermined interval. At this time, the output signal of the microphone is an analog signal, and the audio data generation unit generates audio data that is a digital signal using, for example, an ADC (Analog-to-Digital Converter).

  The analysis control unit adjusts a predetermined interval that is a sampling interval of the audio data generation unit. For example, this adjustment may be performed by outputting a control command to the first to Nth microphone units. The analysis control unit adjusts the sampling interval to be longer than the time required to receive the final stage serial data from the first microphone unit.

  At this time, the analysis control unit can receive the final stage serial data including all the audio data of the first to Nth microphone units until the next audio data is generated. Therefore, even if the audio data is serially transferred, a part of the audio data is not lost, and the audio data of all the microphone units can be reliably received.

(3) In this microphone array device, the analysis control unit includes a first clock used as a serial data shift clock for each of the first to Nth microphone units, and serial data, A control command that is a command for controlling the first to Nth microphone units, and each of the first to Nth microphone units samples the control command with the first clock, and A command analysis unit that analyzes the control command may be included.

(4) In this microphone array device, the command analysis unit may output serial data including the audio data when the control command matches the first command.

(5) In this microphone array device, the Nth microphone unit includes serial data including a predetermined self identification number when the command analysis unit determines that the control command is the second command. And the nth microphone unit identifies the identification included in the serial data received from the (n + 1) th microphone unit when the command analysis unit determines that the control command is the second command. A value obtained by performing a predetermined operation on the number may be used as a self identification number, and serial data including the self identification number may be output.

(6) In this microphone array device, the Nth microphone unit outputs a predetermined pulse signal as serial data when the command analysis unit determines that the control command is a second command, The n-th microphone unit is configured to detect the serial data received from the (n + 1) -th microphone unit based on a delay time from the timing when the command analysis unit determines that the control command is the second command. The serial number received from the (n + 1) th microphone unit may be output after being delayed by a predetermined time.

(7) In this microphone array device, when the control command includes a third command, the command analysis unit, when the identification number included in the control command matches its own identification number, Processing may be performed according to the control command.

  According to these inventions, the analysis control unit outputs a first clock that is also used as a serial data shift clock to each of the first to Nth microphone units. The analysis control unit outputs a control command that is a command for controlling the first to Nth microphone units. The control command is serial data and is output in synchronization with the first clock.

  Each of the first to Nth microphone units includes a command analysis unit that samples the control command with the first clock and analyzes the control command. And the 1st-Nth microphone unit performs the process instruct | indicated according to the control command.

  At this time, the command analysis unit may output serial data including audio data when the control command matches the first command. When the command analysis unit determines that the control command is not the first command but the second command, the first to Nth microphone units obtain their own identification numbers (ID) by calculation. The value may be serially output.

  For example, since the Nth microphone unit farthest from the analysis control unit does not receive an identification number from an adjacent microphone unit, its own identification number is set to 0. That is, since the first to Nth microphone units receive a fixed value (for example, “1”) that is different from the default output value (for example, “0”) when the first to Nth microphone units are not in operation, the Nth microphone unit must be at the end. And its own identification number is set to 0. The other microphone units may use a number obtained by adding 1 to the received identification number of the adjacent microphone unit as its own identification number. At this time, the analysis control unit can grasp how many microphone units are connected by the identification number received from the first microphone unit.

  Here, the first to Nth microphone units can also determine their own identification numbers (ID) by another method that does not perform calculation (addition of 1 in the above example).

  For example, the Nth microphone unit farthest from the analysis control unit may output a predetermined pulse signal as serial data after receiving the second command. Here, for example, when the first to Nth microphone units output ‘0’ during non-operation, the predetermined pulse signal may be ‘1’ having a width corresponding to one clock of the shift clock. Note that the fact that the Nth microphone unit sets its own identification number to 0 is the same as the method of obtaining the self identification number by calculation.

  On the other hand, the other microphone units can determine their own identification numbers based on how much the timing of receiving the serial data from the adjacent microphone units is delayed after receiving the second command. For example, in each microphone unit, serial data is assumed to be delayed by one shift clock. At this time, a microphone unit that has received serial data from an adjacent microphone unit three clocks after receiving the second command can set its own identification number to 3. Similarly, the analysis control unit can grasp how many microphone units are connected depending on how many clocks the delay is.

  In addition, when the command analysis unit determines that the control command includes the third command instead of the first command and the second command, the command analysis unit includes an identification number included in the control command (for example, the third command The process may be performed in accordance with the control command only when the self-identification number coincides with the self-identification number.

  In the microphone array devices of these inventions, the analysis control unit outputs a control command to the first to Nth microphone units, thereby performing processing designated for all or part of the first to Nth microphone units. Can be executed. Therefore, it is possible to realize a microphone array apparatus that can perform flexible processing such as collecting audio data from necessary microphone units.

  Here, the microphone array device requires cables for control commands connected to all of the first to Nth microphone units. However, since the control command is output as serial data, only a 1-bit cable is added, and there is little problem that the cable is congested or requires a large space.

The figure explaining the structure of the microphone array apparatus of this embodiment. The figure which illustrates the system containing the microphone array apparatus of this embodiment. The figure explaining the structure of a microphone unit. The figure explaining another structure of a microphone unit. The figure explaining the structure of an analysis control part. The figure explaining adjustment of a sampling clock. The figure which shows the example of transfer of the control command of this embodiment. The figure explaining the control command of this embodiment. The figure explaining the serial data in the case of the instruction | indication of audio | voice data generation. The figure explaining the serial data in the case of the instruction | indication of ID allocation. FIGS. 11A to 11B are diagrams illustrating serial data in the case of an ID allocation instruction using a method different from that in FIG. 10. The figure explaining the structure of the microphone array apparatus of a comparative example.

1. Overall Configuration of Microphone Array Device FIG. 1 is a diagram illustrating the configuration of a microphone array device 10 according to this embodiment. The microphone array device 10 includes first to Nth microphone units 20-1 to 20 -N and an analysis control unit 30. Here, N is an integer equal to or greater than 2, and the microphone array apparatus 10 includes a plurality of microphone units.

  The positions of the plurality of microphone units are fixed, and the microphone array 12 is configured as a whole. Although the plurality of microphone units can be freely arranged, in the example of FIG. 1, the first to Nth microphone units 20-1 to 20-N are arranged so as to form a square as a whole two-dimensionally.

  The first to Nth microphone units 20-1 to 20-N include microphones 200-1 to 200-N, respectively, and emit sound (for example, audible sound or ultrasonic waves) at the place where they are arranged. Detect. The positions of the microphones 200-1 to 200-N are represented by coordinates, for example, and the analysis control unit 30 can grasp the positions of all the microphones 200-1 to 200-N. The microphones 200-1 to 200-N of this embodiment are small MEMS microphones. In FIG. 1, the microphones 200-1 to 200 -N are drawn out from the first to Nth microphone units 20-1 to 20 -N, but the first to Nth microphone units 20-1 to 20-20 are drawn. It may be built in -N. The microphones 200-1 to 200-N are not limited to MEMS microphones, and general microphones such as dynamic microphones and condenser microphones such as ECMs can be used.

  The first to Nth microphone units 20-1 to 20-N generate audio data based on the output signals of the microphones 200-1 to 200-N, respectively. In this embodiment, the audio data is PCM, and the analog output signals of the microphones 200-1 to 200-N are converted by an ADC (not shown). The audio data is not limited to PCM, and may be an audio signal converted into a digital signal that can be serially transferred. For example, not only uncompressed PCM but also an irreversible compressed digital audio format, a reversible compressed digital audio format, and the like may be used.

  As shown in FIG. 1, in the microphone array device 10, the first to Nth microphone units 20-1 to 20-N are connected in multiple stages. The input data terminal DI of each microphone unit receives serial data from the output data terminal DO of the adjacent microphone unit.

  Here, a more specific description will be given using n-th and n + 1-th microphone units 20-n and 20- (n + 1) (n is an integer satisfying 1 ≦ n ≦ N−1). The nth microphone unit 20-n receives serial data from the (n + 1) th microphone unit 20- (n + 1). The nth microphone unit 20-n outputs serial data including the received serial data and its own audio data from the output data terminal DO to the (n−1) th microphone unit (not shown). That is, the first to Nth microphone units 20-1 to 20-N generate and output new serial data obtained by adding its own audio data to the received serial data.

  Note that the Nth microphone unit 20-N that is farthest from the analysis control unit 30 receives a fixed value “1” (high level of serial data) instead of receiving serial data from the adjacent microphone unit. Here, at the time of non-operation (that is, when serial data is not transferred), the first to Nth microphone units 20-1 to 20-N output a default value “0” (low level of serial data). . Therefore, the Nth microphone unit can recognize that it is the terminal microphone unit by receiving a fixed value “1” instead of the default value “0”.

  The analysis control unit 30 receives final stage serial data 280 that is serial data output from the first microphone unit 20-1. The final stage serial data 280 includes audio data of all, that is, the first to Nth microphone units 20-1 to 20-N.

  At this time, since the first to Nth microphone units 20-1 to 20-N generate audio data having the same bit number (for example, m bits, m is a natural number), the analysis control unit 30 has m bits. It is possible to identify the audio data simply by separating each.

  The analysis control unit 30 can know the start and end of the final stage serial data 280 from the change of the output of the first microphone unit 20-1 from the default value “0”. For example, the final stage serial data 280 may be defined to start with a start bit “1” and end with a stop bit “1”. Then, for example, “1” indicating that the Nth microphone unit 20-N indicates start and “1” that indicates the end of the first microphone unit 20-1 may be added to the serial data. When the analysis control unit 30 knows the number of the first to Nth microphone units 20-1 to 20-N, the total number of bits of the final stage serial data 280 is known. '1' may be omitted.

Then, the analysis control unit 30 generates a data transfer clock DCLK (corresponding to the first clock of the present invention) used as a serial data shift clock, and the first to Nth microphone units 20-1 to 20-. Output to N. Further, the analysis control unit 30 generates a control command CO and outputs it to the first to Nth microphone units 20-1 to 20-N. Details of the control command CO will be described later.

  Here, in order to clarify some features of the microphone array apparatus 10 of the present embodiment, a microphone array apparatus 110 of a comparative example will be described. FIG. 12 is a diagram illustrating the configuration of the microphone array device 110 of the comparative example. The same elements as those in FIG. 1 are denoted by the same reference numerals, and description thereof is omitted.

The microphone array apparatus 110 of the comparative example also includes first to Nth microphone units 120-1 to 120 -N and an analysis control unit 130. However, the analysis controller 130 is connected to the first to Nth microphone units 120-1 to 120 -N on a one-to-one basis, that is, connected to each of them, and receives audio data. Therefore, input data terminals DI _{1 to} DIN corresponding to the first to Nth microphone units 120-1 to 120 _-N are prepared in the connector unit 132 of the analysis control unit 130. And each is connected with the output data terminal DO of the 1st-Nth microphone units 120-1-120-N.

  At this time, audio data is input to the analysis control unit 130 in substantially real time from the first to Nth microphone units 120-1 to 120 -N. However, as the number of first to Nth microphone units 120-1 to 120-N increases, the number of cables greatly increases, so that it is necessary to secure a space for the cables.

  In addition, since the area of the connector part 132 of the analysis control unit 130 also increases as the first to Nth microphone units 120-1 to 120-N increase, it is difficult to reduce the size of the analysis control unit 130. is there. Also, it is not easy to increase or decrease the number of terminals of the connector portion 132 in response to the change in the number of the first to Nth microphone units 120-1 to 120-N.

  Compared with the microphone array apparatus 110 of the comparative example shown in FIG. 12, the microphone array apparatus 10 of the present embodiment has a structure that outputs serial data including audio data to the adjacent microphone unit, so the number of microphone units ( In this example, even if N) increases or decreases, the audio data can be transferred with one cable. Therefore, the space required for the cable can be reduced and the size of the connector for connecting the cable can be reduced, so that the microphone array device 10 that can be miniaturized is realized.

  In the microphone array device 10 of the present embodiment, there is one cable for transferring serial data including audio data, but there may be a plurality of cables. For example, when parallel-to-serial conversion of 2-byte audio data, the parallel data is converted separately into the upper 1 byte and the lower 1 byte (or separated after conversion), and two cables are used. Can be serially transferred to shorten the time required for the transfer. Even in this case, as compared with the microphone array device 110 of the comparative example, the space required for the cable can be reduced, and the size of the connector for connecting the cable can be reduced.

2. Example of Use of Microphone Array Device FIG. 2 is a diagram illustrating a system including the microphone array device 10. The microphone array apparatus 10 of this embodiment receives audio data from the microphone array 12 with a single cable. Therefore, the size of the connector portion can be reduced, and the analysis control unit 30 can be realized as a small peripheral device connected to the PC 40 via USB, for example.

  At this time, the first to Nth microphone units 20-1 to 20-N also have no problem such as cable congestion and space securing, so that the microphone array 12 that does not limit the shape can be configured. Also, the PC 40 receives the respective audio data of the first to Nth microphone units 20-1 to 20-N identified by the analysis control unit 30 via the USB, and executes various application programs. For example, the PC 40 may display the magnitude of the sound pressure at each position of the first to Nth microphone units 20-1 to 20-N on the display, or perform sound source tracking and sound source separation for the user. Confirmation of the position and identification of individuals may be executed.

  As shown in FIG. 2, the microphone array device 10 can make the analysis control unit 30 as small as a peripheral device of the PC 40, and it is not necessary to secure a cable space, so that the microphone array 12 having a free shape can be configured. Therefore, the system including the microphone array apparatus 10 can also have a small and flexible configuration, and is easy to carry, for example.

3. Configuration of Microphone Unit The overall configuration of the microphone array apparatus 10 has been described with reference to FIGS. 1 to 2. With reference to FIGS. 3 to 4, the configurations of the first to Nth microphone units 20-1 to 20 -N are described. The configuration will be described. The same elements as those in FIGS.

  Here, the first to Nth microphone units 20-1 to 20-N have the same configuration. That is, “−1” to “−N” included in these codes are for distinguishing the plurality of microphone units 20 from each other, and do not mean that the configurations are different. In the following description, the first to Nth microphone units 20-1 to 20-N may be described as the microphone unit 20 without any particular notice in order to avoid duplication. Further, the microphones 200-1 to 200-N may be described as the microphone 200.

  FIG. 3 is a diagram for explaining the configuration of the microphone unit 20. The microphone unit 20 includes a microphone 200, a command analysis unit 210, an audio data generation unit 220, and a data transmission / reception unit 230.

  The microphone 200 is a MEMS microphone, detects a sound at the place where the microphone unit 20 is disposed, and outputs an output signal 202 to the sound data generation unit 220. Here, the output signal 202 is an analog signal.

  The audio data generation unit 220 converts the output signal 202 from the microphone 200 into a digital signal by a built-in ADC, and generates audio data 222. The audio data 222 here is parallel data, and parallel-serial conversion is performed by the data transmission / reception unit 230 at the subsequent stage.

  The audio data generation unit 220 generates the audio data 222 at the timing of the sampling clock 212 received from the command analysis unit 210. Here, the audio data 222 is PCM (Pulse Code Modulation) data of m bits (m is a natural number).

  The command analysis unit 210 analyzes the control command CO that is an instruction from the analysis control unit 30 and outputs an internal control signal 214 to, for example, the data transmission / reception unit 230 based on the result of the analysis. Further, the command analysis unit 210 outputs a sampling clock 212 having a frequency based on an instruction of the control command CO to the audio data generation unit 220.

The data transmitter / receiver 230 includes registers R _{1 to} R _m for receiving the audio data 222 and performing parallel-serial conversion. Note that the registers R _{1 to} R _m are not limited to the audio data 222 and may receive, for example, the identification number of the microphone unit 20. Further, although illustration of wiring is omitted, the registers R _{1 to} R _m perform a shift operation with the data transfer clock DCLK.

Here, it is assumed that the selector appropriately selects data according to an instruction from the internal control signal 214 or a control circuit of the data transmission / reception unit 230 (not shown). For example, the registers R _{1 to} R _m perform a shift operation after receiving the audio data 222 according to an instruction from the control circuit of the data transmission / reception unit 230. Further, in response to an instruction of the internal control signal 214, serial data from the adjacent microphone unit 20 received via the input data terminal DI is output from the output data terminal DO, and subsequently, the registers R _{1 to} R _m are self-registered. Audio data 222 is output.

Since the serial data from the adjacent microphone unit 20 received via the input data terminal DI passes through the register R ₀ in the example of FIG. 3, it is delayed by one clock with the data transfer clock DCLK from the output data terminal DO. Is output. Further, the microphone 200 may include some or all of the functions of the audio data generation unit 220. For example, the microphone 200 may receive the sampling clock 212 and convert it into the audio data 222.

  FIG. 4 is a diagram for explaining another configuration of the microphone unit 20. The microphone unit 20 shown in FIG. 3 adds and outputs its own audio data 222 to the end of the received serial data. On the other hand, the microphone unit 20 shown in FIG. 4 can add and output its own audio data 222 to the beginning of the received serial data.

The microphone unit 20 in FIG. 4 includes a data transmission / reception unit 230A. Unlike the data transmission / reception unit 230 of FIG. 3, the data transmission / reception unit 230A also outputs serial data received from the adjacent microphone unit 20 via the input data terminal DI via the registers R _{1 to} R _m . The data transmitting / receiving unit 230A can first delay the serial data from the adjacent microphone unit 20 by m clocks by the data transfer clock DCLK, and first convert the audio data 222 into serial data and output the serial data.

  Whether the data transmission / reception unit 230 shown in FIG. 3 or the data transmission / reception unit 230A shown in FIG. 4 is used, the microphone unit 20 outputs serial data to which its own audio data is added. Therefore, the analysis control unit 30 receives the final stage serial data 280 including all audio data of the first to Nth microphone units 20-1 to 20-N.

  The microphone unit 20 in FIG. 4 is configured by the same elements as the microphone unit 20 in FIG. 3 except for the data transmission / reception unit 230A, and description of elements other than the data transmission / reception unit 230A is omitted.

4). Configuration of Analysis Control Unit The configuration of the analysis control unit 30 will be described with reference to FIG. The same elements as those in FIGS. 1 to 4 are denoted by the same reference numerals, and description thereof is omitted.

  FIG. 5 is a diagram illustrating the configuration of the analysis control unit 30. The analysis control unit 30 includes a clock generation unit 300, a processing unit 310, a control command generation unit 320, a data reception unit 330, and a data buffer 340.

The clock generation unit 300 generates and outputs a data transfer clock DCLK. The clock generation unit 300 may be configured with an oscillator such as a crystal resonator and an oscillation circuit, for example, and may further include a PLL or a frequency divider. The data transfer clock DCLK is supplied to the microphone unit 20 and used as a shift clock for transferring at least serial data.

  The processing unit 310 analyzes the final stage serial data 280 along with the control of the microphone array device 10. The processing unit 310 is a CPU as in the present embodiment, for example, and may control the microphone array device 10 or analyze the final stage serial data 280 according to a program.

  The processing unit 310 controls the microphone array apparatus 10 by outputting an operation mode signal 312 that designates an operation mode. The format of the operation mode signal 312 is not limited, but may be parallel data of several bits, for example.

  Further, the processing unit 310 may receive the audio data subjected to serial-parallel conversion from the data buffer 340 and analyze the correspondence with the first to Nth microphone units 20-1 to 20-N. Then, the processing unit 310 may output necessary data outside or inside the analysis control unit 30. At this time, the processing unit 310 may output necessary data from the data buffer 340 to the outside or the inside of the analysis control unit 30. The outside of the analysis control unit 30 may be a PC 40 connected by USB as shown in FIG.

  Note that the processing unit 310 may receive data other than audio data in the data buffer 340. For example, a status signal indicating that the command instructed by the first to Nth microphone units 20-1 to 20-N has been completed may be received from the data receiving unit 330.

  Based on the operation mode signal 312 from the processing unit 310, the control command generation unit 320 generates and outputs a control command CO for serial data synchronized with the data transfer clock DCLK. The relationship between the timing of the data transfer clock DCLK and the control command CO will be described later.

Data receiving unit 330 receives via the input data terminal DI of the last stage serial data 280 from the first microphone unit 20-1, a serial using register _r 1 ~r _m - performing parallel conversion.

  The data buffer 340 stores the audio data serial-parallel converted by the data receiving unit 330. At this time, the data buffer 340 and the processing unit 310 are connected by, for example, an m-bit bus, and high-speed transfer is possible. In addition, since the data buffer 340 sequentially stores the audio data, the processing unit 310 can access the audio data of the specific microphone unit 20 by designating an address, for example.

5. Control of analysis control unit 5.1. Adjustment of Sampling Clock FIG. 6 is a diagram for explaining the adjustment of the sampling clock 212 by the analysis control unit 30. The analysis control unit 30 can adjust the cycle of the sampling clock 212, which is the timing at which the microphone unit 20 generates audio data, using the control command CO. Conversely, the microphone unit 20 adjusts the sampling clock 212 in accordance with the control command CO.

In FIG. 6, there are rising edges of the sampling clock 212 at time t ₁ and time t ₄ . That is, T _sc, which is the interval between them, is the period of the sampling clock 212. On the other hand, the last stage serial data 280 is completed at time _{t 3} the transfer is started at time _{t 2.} That is, the analysis control unit 30 starts the receipt of voice data in time t _2, the receive audio data of all of the microphone unit 20 at time t _3, these intervals are T _d. Then, at time t ₅ of the audio data obtained at the next sampling transfer is started.

The analysis control unit 30 acquires audio data from all the microphone units 20 constituting the microphone array 12 in order to cause the subsequent PC 40 (see FIG. 2) to perform accurate sound source tracking and sound source separation. There is a need. Using the notation of FIG. 6, the analysis control unit 30 indicates that the period T _sc of the sampling clock 212 (corresponding to the predetermined interval of the present invention) is longer than the time T _d required to receive the final stage serial data 280. It is necessary to adjust so that it becomes.

That is, the microphone array device 10 of the present embodiment serially transfers the audio data of the first to Nth microphone units 20-1 to 20-N in multiple stages. Therefore, it takes time compared to the case where cables for transferring audio data are independently connected to the first to Nth microphone units 20-1 to 20-N (see FIG. 12). However, if the analysis control unit 30 adjusts the cycle T _sc of the sampling clock 212 so that the transfer time (T _d ) of the final stage serial data 280 is shorter than the cycle (T _sc ) of the sampling clock 212, the analysis control is performed. The unit 30 can acquire the audio data from all the microphone units 20 without missing it.

5.2. Control Command In the microphone array device 10 of this embodiment, the analysis control unit 30 gives an instruction to all or a part of the first to Nth microphone units 20-1 to 20-N by the control command CO, so that the voice Not only serial data including data but also various serial data can be transferred.

  At this time, the control command CO output from the analysis control unit 30 is serial data. Therefore, even if the control command CO is used, only a 1-bit cable is added, and the problem that the cable is congested and requires a large space is unlikely to occur.

  FIG. 7 is a diagram illustrating an example of transfer of the control command CO. In the cable to which the control command CO is transferred, if the control command CO is not output, it is assumed that the state is ‘1’. It is assumed that the control command CO is determined to start at “01” and end at “10”.

  In the example of FIG. 7, the portion indicated by COV is the transferred control command CO. The command analysis unit 210 of the microphone unit 20 samples the control command CO at the rising edge of the data transfer clock DCLK and recognizes that the control command CO of “010010” has been received.

  FIG. 8 shows the control command CO and the instruction content. Note that FIG. 8 does not show all the control commands CO, and there are other control commands CO for changing the period of the sampling clock 212, for example, but the description is omitted here.

  As shown in FIG. 8, “010010” in the example of FIG. 7 is the first command, and the analysis control unit 30 instructs generation of audio data. The command analysis unit 210 of the microphone unit 20 causes the data transmission / reception unit 230 to output serial data including the audio data 222 when the control command CO matches the first command.

  As shown in FIG. 8, “011110” is a second command, assigns a unique identification number (ID) to each microphone unit 20, and indicates how many microphone units 20 the analysis control unit 30 is connected to. In order to grasp it, the identification number is serially output.

  Although the identification number is used in the present embodiment, an identification symbol or an identification character may be used instead of the identification number. In other words, the identification number is not limited as long as each of the microphone units 20 can be distinguished.

  As shown in FIG. 8, “0110” at the head is the third command. The command analysis unit 210 determines that the first command and the second command match the control command CO, but determines whether the third command is included in the control command CO.

  The third command uses only the identification number obtained by the second command to cause only a part of the microphone units 20 to execute processing (control a specific microphone unit 20). When “0110” is included in the control command CO, the command analysis unit 210 performs processing according to the subsequent control code only when the subsequent identification number matches the own identification number.

  Here, the control code is a code composed of ‘0’ and ‘1’ that do not match each other. The process according to the control code may be, for example, reset, self-test, parameter change for changing a filter coefficient or gain, and status acquisition.

  Since the analysis control unit 30 has the second command and the third command, the microphone array apparatus 10 according to the present embodiment is similar to the case where the analysis control unit 30 is connected to each of the microphone units 20. Only the specific microphone unit 20 can execute processing.

  9 to 11B illustrate serial data output from the microphone unit 20 in response to the control command CO from the analysis control unit 30. FIG. In FIG. 9 to FIG. 11B, it is assumed that the total number (N) of the microphone units 20 is 3 for convenience of explanation. Moreover, the same code | symbol is attached | subjected to the same element as FIGS. 1-8, and description is abbreviate | omitted.

  FIG. 9 illustrates serial data when the control command CO is the first command (‘010010’). The command analysis units 210 of the first to third microphone units 20-1 to 20-3 determine that the control command CO matches the first command, and serially include the audio data 222 in the data transmission / reception unit 230. Output data.

  The third microphone unit 20-3 outputs a start bit “1” indicating the start and its own audio data (3). The second microphone unit 20-2 adds and outputs its own audio data (2) to the end of the received serial data. Then, the first microphone unit 20-1 outputs final stage serial data 280 obtained by adding its own audio data (1) to the end of the received serial data. In the present embodiment, it is assumed that “1” (stop bit) indicating the end of serial data is omitted.

The analysis control unit 30 can receive the audio data of all the microphone units 20 as the final stage serial data 280. Then, after removing the start bit '1', serial using register _r 1 ~r _m - performing parallel conversion, the first to third respective voice data of the microphone unit 20-1 to 20-3 Can be identified.

  FIG. 10 illustrates serial data when the control command CO is the second command (‘011110’). The command analysis units 210 of the first to third microphone units 20-1 to 20-3 determine that the control command CO matches the second command, and include their own identification numbers in the data transmission / reception unit 230. Output serial data.

  Since the third microphone unit 20-3 has a fixed value “1” input and can be identified as the terminal, the self identification number is set to 0, the start bit “1” and the self identification number “0000”. (In this example, 4-bit display) is output. The second microphone unit 20-2 performs a calculation of adding 1 to the identification number of the received serial data, and sets 1 as the calculation result as its own identification number. The start bit “1” and its own identification number “0001” are output. The first microphone unit 20-1 performs a calculation of adding 1 to the identification number of the received serial data, and sets 2 as the calculation result as its own identification number. Then, the final stage serial data 280 including the start bit “1” and its own identification number “0010” is output.

  The analysis control unit 30 can receive the identification number “2” of the first microphone unit 20-1 as the final stage serial data 280. Then, the analysis control unit 30 can recognize that the three microphone units 20 are connected to the microphone array device 10 by adding 1 to the identification number “2” included in the final stage serial data 280. .

  FIG. 11A to FIG. 11B illustrate another serial data when the control command CO is the second command. 11A to 11B, a predetermined pulse signal is transferred without transferring the identification number, and the identification number is determined based on the delay time. In this example, the predetermined pulse signal is a value different from the default value “0” (ie, “1”) output when the first to third microphone units 20-1 to 20-3 are not operating, and has a width. Is a signal for one clock of the shift clock. Note that the same reference numerals are given to the same elements as those in FIG.

As shown in FIG. 11A, serial data 276 and 278 are output from the first microphone unit 20-1 and the second microphone unit 20-2, respectively. In this example, the transferred serial data 276, serial data 278, and final stage serial data 280 have the same contents as a response to the second command. However, each microphone unit 20 causes a delay of one clock of the data transfer clock DCLK (corresponding to the predetermined time of the present invention). The delay of one clock of DCLK can be realized by the configuration of FIG. 3, for example. Moreover, it can be realized by outputting the value of the register R ₁ from the output data terminal DO in FIG. 4, for example.

FIG. 11B illustrates a waveform diagram of the serial data 276, the serial data 278, and the final stage serial data 280. First to third each command analyzer 210 of the microphone unit 20-1 to 20-3 receives the control command CO at the same time, a second command at time _{t 1} ( '011110') to coincide with the determined To do.

The third microphone unit 20-3, since the fixed value "1" can be identified as a terminal is inputted, at time _{t 2, the} first through third microphone unit 20-1 to 20-3 output A pulse signal having a value different from the default value “0” (ie, “1”) is output as serial data 276. The self identification number is 0.

Incidentally, the serial data 276 in this example in synchronization with the falling edge of the data transfer clock DCLK, the serial data 278, the final-stage serial data 280 is output, the value of the serial data 276 from the previous time t ₂ is '1' It has become.

Second microphone unit 20-2 receives the (pulse signal of '1') the serial data 276 at time _{t 2.} Since the delay from time t _{1 when} it is determined that the control command CO matches the second command is one clock of DCLK, it is possible to determine that its own identification number is 1.

  The delay time may be counted, for example, by using a counter that starts counting up when the control command CO matches the second command using DCLK as a clock signal. Then, the second microphone unit 20-2 delays the serial data 276 by one clock of the data transfer clock DCLK and outputs it as serial data 278.

The first microphone unit 20-1 receives the (pulse signal of '1') the serial data 278 at time _{t 3.} Then, the control command CO delay from the time t ₁ that is determined to match the second command is the two clocks of DCLK, it can be determined that a two self-identification number. Then, the first microphone unit 20-1 delays the serial data 278 by one clock of the data transfer clock DCLK and outputs it as the final stage serial data 280.

Analysis control unit 30 receives the last stage serial data 280 (a pulse signal of '1') at time _{t 4.} Then, the delay from the time t ₁ which has finished sending the second command as a control command CO is 3 clocks of DCLK, recognize that three microphone units 20 to the microphone array device 10 is connected be able to.

  Note that the delay time of serial data generated in each microphone unit 20 is not limited to one clock of the data transfer clock DCLK, but may be two or more clocks. In this example, a pulse signal having a width of “1” (high level) corresponding to one clock of DCLK is used. However, a pulse signal having a width of two or more clocks of DCLK may be used. Data of a pattern (for example, “101” etc.) may be used.

  As described above, since the microphone array apparatus 10 of the present embodiment is configured to output serial data including audio data to the adjacent microphone unit, even if the number of microphone units increases or decreases, at least one cable is used. Audio data can be transferred with. Therefore, the space required for the cable can be reduced and the size of the connector for connecting the cable can be reduced, so that the microphone array device 10 that can be miniaturized is realized.

  The present invention is not limited to these examples, and the present invention includes substantially the same configuration (for example, a configuration having the same function, method and result, or a configuration having the same purpose and effect) as the configuration described in the embodiments. In addition, the invention includes a configuration in which a non-essential part of the configuration described in the embodiment is replaced. In addition, the present invention includes a configuration that achieves the same effect as the configuration described in the embodiment or a configuration that can achieve the same object. In addition, the invention includes a configuration in which a known technique is added to the configuration described in the embodiment.

In particular, “0” and “1” in the above examples may be reversed. For example, when the control command CO is not transmitted, the signal level of the wiring is the default value “1” (see FIG. 7), but may be “0”. At this time, the control command CO may start with “10”. The microphone unit 20 outputs the default value “0” from the output data terminal DO when not operating (see FIG. 6), but may be “1”. At this time, “0” may be input as a predetermined fixed value to the input data terminal DIN of the _Nth microphone unit 20-N.

DESCRIPTION OF SYMBOLS 10 Microphone array apparatus, 12 Microphone array, 20 Microphone unit, 20-1-20-N 1st-Nth microphone unit, 30 Analysis control part, 40
PC, 110 microphone array device, 120-1 to 120-N 1st to Nth microphone units, 130 analysis control unit, 132 connector unit, 200 microphone, 200-1 to 200-N microphone, 202 output signal, 210 command Analysis unit, 212 sampling clock, 214 internal control signal, 220 audio data generation unit, 222 audio data, 230 data transmission / reception unit, 230A data transmission / reception unit, 276 serial data, 278 serial data, 280 final stage serial data, 300 clock generation unit , 310 processing unit, 312 operation mode signal, 320 control command generation unit, 330 data receiving unit, 340 data buffer, CO control command, DCLK data transfer clock, DI input data _terminal, DI 1 -DI _N input data Data terminals, DO output data _terminals, R 1 to R _{m registers,} r 1 ~r _m registers

Claims (6)

First to Nth (N is an integer of 2 or more) microphone units that include a microphone and generate audio data based on an output signal of the microphone;
An analysis control unit,
The Nth microphone unit is
Outputting serial data including the audio data generated by the Nth microphone unit;
The n-th microphone unit (n is an integer satisfying 1 ≦ n ≦ N−1) is
Serial data received from the (n + 1) th microphone unit;
Outputting serial data including the audio data generated by the nth microphone unit;
The analysis control unit
Receiving final serial data, which is serial data output from the first microphone unit;
Identifying the audio data of each of the first to Nth microphone units included in the final stage serial data;
The analysis control unit
In each of the first to Nth microphone units,
A first clock also used as a serial data shift clock;
A control command which is serial data and is a command for controlling the first to Nth microphone units;
Each of the first to Nth microphone units is
A microphone array apparatus , comprising: a command analysis unit that samples the control command with the first clock and analyzes the control command . The microphone array apparatus according to claim 1, wherein
Each of the first to Nth microphone units is
Including an audio data generation unit that generates the audio data by sampling the output signal of the microphone at a predetermined interval;
The analysis control unit
A microphone array device that adjusts the predetermined interval of the audio data generation unit to be longer than a time required to receive the final stage serial data from the first microphone unit. The microphone array device according to claim 1 or 2 ,
The command analysis unit
If the control command matches the first command,
A microphone array device for outputting serial data including the audio data. The microphone array device according to claim 3 ,
The Nth microphone unit is
When the command analysis unit determines that the control command is the second command,
Output serial data including a predetermined identification number,
The nth microphone unit is
When the command analysis unit determines that the control command is the second command,
A value obtained by performing a predetermined calculation on the identification number included in the serial data received from the (n + 1) th microphone unit is set as its own identification number,
A microphone array device that outputs serial data including its own identification number. The microphone array device according to claim 3 ,
The Nth microphone unit is
When the command analysis unit determines that the control command is the second command,
Output a predetermined pulse signal as serial data,
The nth microphone unit is
Based on a delay time from serial data received from the (n + 1) th microphone unit from a timing when the command analysis unit determines that the control command is the second command, a self identification number is determined.
A microphone array device that outputs serial data received from the (n + 1) th microphone unit with a predetermined time delay. The microphone array device according to claim 4 or 5 ,
The command analysis unit
If the control command includes a third command,
A microphone array device that performs processing in accordance with the control command when the identification number included in the control command matches its own identification number.

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