JP4295781B2 - Information provision system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an information providing system capable of clearly separating coded information from other sound (source sound) such as music and voice, even when the source sound exists and sound of the information and the source sound are superposed and input to a terminal. <P>SOLUTION: A transmission device 10 of the information providing system 1 transmits various kinds of information, by utilizing frequency in which transmission frequency and its subharmonic are located in a gap between notes of an equal temperament scale, as the transmission frequency of a sound code. In a receiving terminal side, the sound code is extracted and restored by separating it from the source sound by a Fast Fourier Transform circuit 206 and a sound code extracting circuit 207 etc. <P>COPYRIGHT: (C)2008,JPO&amp;INPIT

Description

  The present invention relates to an information providing system for providing various types of information to a terminal.

  Systems for providing various types of information to terminals have been conventionally provided. For example, in radio or television broadcasting, character codes, graphic information, information on programs, etc. are superimposed (multiplexed) on broadcast signals, and various information is provided to television receivers and radio receivers in addition to normal program contents. Character multiplex broadcasting is performed.

  However, in the text multiplex broadcasting system, it is necessary to superimpose digital information on the radio waves of TV and radio, so large broadcasting station facilities are indispensable, costly, and information is easily provided to terminals. Can not do it. Also, the method of taking a QR code using a camera of a mobile phone cannot be used with a terminal not equipped with a camera, and is very difficult for beginners and people unfamiliar with machines.

In view of such problems, a new information providing method has been developed that provides various types of information to a terminal as sound using air as a medium. For example, these methods are disclosed in Patent Documents 1 to 3 below. . In this way, if it is a method of transmitting information as sound using air as a medium, it is possible to easily transmit information at low cost by using an existing speaker and a microphone mounted on the terminal. is there.
JP 2003-186500 A Japanese Patent No. 3822224 Japanese Patent No. 3833579

  Patent Document 1 discloses that information to be transmitted is transmitted as sound through an input / output interface of an acoustic device that handles existing sound by using an information encoding device that converts the information to be transmitted into sound. In addition, the information transmission system reproduces the transmission target information based on the voice received by the information decoding apparatus, and the sound including the encoded information becomes comfortable music that can be heard actively by humans. This is an encoding method for the purpose.

  In addition, the information providing systems disclosed in Patent Documents 2 and 3 were developed by the present inventors and encode various information as data frames in milliseconds including a preamble for synchronizing timing. Thus, information is transmitted as sound using air as a medium.

  The present invention was born in the process of developing a system for transmitting information as sound using air as a medium as disclosed in Patent Documents 2 and 3 above. In an environment where information is transmitted as sound using air as a medium, other sounds (source sound) such as music and voice exist, and the information sound and the source sound are superimposed and taken into the terminal. However, an object of the present invention is to provide an information providing system capable of reliably separating encoded information from a source sound and restoring it.

  In order to solve the above-described problems, the information providing system according to the present invention converts various encoded information into sound pressure vibrations that use the frequency of the gap of each average rate scale in the audible sound range and transmits the information. A transmitting device that receives the sound pressure vibration and decodes the various information, and includes a filtering unit that filters the transmission frequency of the transmitting device and the vicinity of the subharmonic frequency. And transmitting information from the transmitting device to the terminal as sound using air as a medium.

  The transmitting device according to the present invention is a transmitting device for transmitting various information to a terminal in an information providing system, and includes a computing means for encoding various information, and the various encoded information. Is transmitted to the sound pressure vibration using the frequency of the gap of each sound of the average rate scale in the audible sound range, and is transmitted to the terminal as sound using air as a medium. Is transmitted.

  An information providing method according to the present invention is an information providing method for providing various types of information to a terminal, and includes an encoding step for encoding various types of information and the encoded various types of information in an audible sound range. Of these, a transmitting step of transmitting by converting the sound pressure vibration using the frequency of the gap of each sound of the average rate scale, a receiving step of receiving the sound pressure fluctuation at the terminal, a transmitting frequency of the transmitting step at the terminal, and its And a restoration step of decoding the sound pressure vibration while filtering the vicinity of the subharmonic frequency to restore the various information.

  The broadcasting facility according to the present invention is a broadcasting facility that performs broadcasting such as television and radio, for encoding various information and superimposing it on a broadcast signal, and for transmitting the broadcast signal as a radio wave. A transmission signal, and the encoded various information superimposed on the broadcast signal when the encoded various information is superimposed on the broadcast signal when received by the broadcast receiver and reproduced. Is a signal configured to be transmitted after being converted into sound pressure vibration using the frequency of the gap of each average rate scale in the audible range from the speaker of the broadcast receiver.

  According to the present invention, even if there is a sound (source sound) of another music system such as music or voice, and the information sound and the source sound are superimposed and taken into the terminal, the encoded information Can be reliably separated from the source sound.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the information providing system according to the present embodiment, various information such as a message is transmitted as sound (sound pressure vibration) from the speaker to the terminal on the information transmitting device side, and this sound pressure vibration is transmitted from the microphone on the terminal side. The received information is recognized by receiving and decoding. The present embodiment is characterized in that the transmission frequency of sound pressure vibration information (hereinafter referred to as “sound code”) does not overlap the average temperament scale.

(First embodiment)
FIG. 1 is a diagram schematically showing a configuration of an information providing system 1 according to the present embodiment. As shown in FIG. 1, the information providing system 1 transmits information to a transmitting device 10 via a transmitting device 10 that transmits various types of information as sound pressure vibration information, a mobile phone 20 that receives various types of information, and the Internet 40. The server 50 is connected. The transmission device 10 includes a keyboard 11 as an input means, a display 12, a speaker (PA) 13 for transmitting various information as sound, and a PC (personal computer) main body 14 connected thereto. Here, PA is an abbreviation for Public Address and means a general term for an electric sound loudspeaker.

  Although not shown, the PC main body 14 includes an MPU (microprocessor) as a calculation means for performing various calculations and controls, a memory used as a work area for calculations, various data and programs, and the like. Built-in storage device (hard disk) for storing

  The mobile phone 20 includes a microphone 21 and a display 22 for picking up sound from the speaker 13. Although not shown, the mobile phone 20 incorporates a processor and a memory as calculation means for performing various calculations and controls.

  The transmission device 10 of the information providing system 1 described above is installed in a commercial facility such as a department store, a supermarket, a shopping street, a movie theater, an amusement park, an amusement facility, or the like. Various information (sound pressure vibration information) converted into sound pressure vibration is transmitted from the speaker 13 alone or superimposed on other sounds such as music and announcements flowing in the facility. A customer who visits the facility can obtain various information by receiving this sound pressure vibration information using his / her mobile phone 20.

  As various kinds of information, a message regarding a product, an event, a facility guide, etc., and text information such as a related HP URL are provided to the owner of the terminal. A customer visiting the facility can obtain further information or read a product description directly by reading the URL and accessing the Internet using the network function of the terminal.

  Of course, the place where the transmission device is installed is up to the information provider, and may be installed in other places as appropriate. The content of the provided information is not limited to character information, and image information or the like may be provided.

  Next, the process of generating a sound code to be transmitted to the mobile phone 20 in the transmission device 10 will be described in detail. FIG. 2 is a block diagram showing a conceptual circuit for realizing the function of generating a sound code.

  PA Source (PA source) shown in the figure means a source sound circulated from the PA, that is, a sound on which a sound code is superimposed in a facility or the like where the transmitting device 10 is installed. For example, when a music CD is played from the PA, the audio signal of the music is a PA source signal, and when nothing is played, the PA source signal is zero.

  The PA source signal is used to determine a timing for generating a sound code, a sound pressure level, and the like. The PA source signal is first converted into a digital signal by the A / D conversion circuit 101 and sent to the frame division circuit 102, the peak / average detector 103, the rising detector 104, and the masking circuit 105 to generate a sound code. Parameters for are determined. Each circuit sets appropriate parameters while referring to a code profile.

  The code profile refers to the information provider accessing the server 50 via the transmitter 10 in advance and registering various information (messages) desired to be transmitted, as well as the signal level, transmission frequency, timing, etc. required by the information provider. It is a profile created by setting. The information provider can easily create the code profile by accessing the server 50 and inputting according to the request item displayed on the display 11. The created code profile is transmitted from the server 50 to the PC main body 14 and stored, and is referred to when generating a sound code as described above.

  In the frame dividing circuit 102, the PA source signal is divided into frame units every 1 to 5 ms, and the subsequent processing is performed in frame units. For this processing unit, an optimum value is appropriately set with reference to the characteristics of the PA source and the code profile.

  The peak / average detector 103 detects the peak value and average value of the PA source signal, and serves as a reference parameter for setting the sound pressure level when the sound code is transmitted.

  The rising detector 104 detects the rising edge of the PA source signal. The point where the PA source signal rises means that the sound suddenly increases, and the detected value here is used to obtain a masking effect described later.

  In the masking circuit 105, a parameter for transmitting a sound code is set with reference to the rising edge of the PA source signal at a timing at which the masking effect is remarkably obtained. The masking effect is one of psychoacoustic evaluations in which a small sound (signal with low sound pressure) is drowned out by a loud sound (signal with high sound pressure).

  Subsequently, on the basis of the parameters thus obtained, the chord generation circuit 106 encodes various information (messages) included in the chord profile to generate a sound code. Further, the code generation circuit 106 performs a scramble process at the time of code generation. The scramble process is a process for preventing any one of the signals 0 and 1 from being generated continuously, and here, a pseudo-random signal is used. As will be described later, since NRZ modulation is used in this system, when either 0 or 1 signals are continuous, the apparent frequency is lowered by the continuous number. To avoid this, scramble processing is performed, and the occurrence frequency of 0 and 1 is as close as possible to 1: 1.

  The transmission frequency of the generated sound code is set in the code profile, and is set by the information provider according to the situation of the place where the source sound and the sound code are provided. This embodiment is characterized in that the transmission frequency of the sound code is set so as not to overlap with each sound of the average rate scale obtained by dividing one octave into twelve, and this will be described in detail below.

FIG. 3 is a diagram showing the frequency of each sound of the average rate scale. The fundamental sound is La (220Hz), La # (233Hz), Shi (247Hz), De (262Hz), De # (277Hz), Les (294Hz), Les # (311Hz), Mi (330Hz), Fa (349Hz) , Fa # (370Hz), Seo (392Hz), Seo # (415Hz), and the frequencies of these harmonics (2-9 times, 16 times, 32 times) are shown. Each frequency of the fundamental tone is calculated as 220 × 2 ^{n / 12} (n is an integer from 1 to 12) based on the La frequency (220 Hz). The frequency of the overtones is the frequency of these fundamentals doubled, tripled, quadrupled, etc .: 2nd overtones are 1 octave, 4th overtones are 2 octaves, 8th overtones are 3 octaves, 16th overtones are 4 octaves, 32nd overtone Becomes a scale 5 octaves above.

Here, when a sound of a musical instrument or the like is emitted, its overtone is also emitted. In FIG. 3, when the fundamental tone is emitted, the second harmonic, the third harmonic, the fourth harmonic, and so on are also emitted at the same time, although the sound pressure gradually decreases. In this embodiment, the frequency of the gap between the basic and overtone frequencies is used as the sound code transmission frequency. Sound code, as described above, but is transmitted by scrambled process, since sometimes 1 or 0 is continuous, when the transmission frequency of the sound code to f _0, 1/2 f _0, 1 / Subharmonic signals of 3 f ₀ and 1/4 f ₀ are also generated. In the present embodiment, both of the f ₀ and its subharmonics can so as not to overlap the fundamental and harmonics of the average rate scale is set to f _0. In this embodiment, scramble processing is applied, and it is sufficient to consider 1/4 f ₀ as the subharmonic of the sound code.

Thus, if f ₀ is determined such that the sound code transmission frequency f ₀ and its subharmonics are located in the gaps between the sounds of the average rate scale, especially if the source sound is a music sound, the sound code Therefore, if a predetermined filtering process is performed on the reception side, the sound code can be easily separated from the source sound and extracted.

Figure 4 is a graph showing the frequency of the thus the obtained oscillation frequency f ₀ and its subharmonics (to 1/4). In this figure, 7,249 Hz, 7,680 Hz, 8,137 Hz, 8,621 Hz, 9,133 Hz, 9,677 Hz, 10,252 Hz, 10,862 Hz, 11,508 Hz, 12,192 Hz are listed as f ₀ candidates. None of them, including waves, overlap with the sounds of the average rate scale in FIG.

of In selecting f _0, because up also the data transmission rate by increasing the f _0, in this respect, although better f ₀ is large, a speaker and the performance and the microphone, in consideration of the characteristics of the source noise or the like, it may be determined an optimum f ₀ from f ₀ shown in FIG. Of course, the transmission frequency of the sound code in the present embodiment is not limited to f ₀ shown in FIG. 4, and other frequencies can be appropriately used as long as they do not overlap each sound of the average rate scale. .

Here, the transmission frequency f ₀ = 12,192 Hz can be obtained by, for example, obtaining an intermediate frequency between the basic sound of the F # and the So and multiplying it by 32. That is, ((370 + 392) / 2) × 32 = 12,192. The other f ₀ shown in FIG. 4 can be obtained in the same manner. Of course, the transmission frequency f ₀ of the sound code does not need to be in the middle between the sounds of the average rate scale, and can be separated from the source sound on the receiving side as long as it does not overlap each sound. However, the sound wave of the sound code is affected by noise while propagating in the air and has a certain bandwidth. Therefore, it is necessary to filter and extract a frequency band having a certain width on the receiving side, and it is necessary to separate the transmission frequency f ₀ from each sound of the average rate scale to some extent. This should also be considered similarly subharmonic 1 / 2~1 / 4 f _0.

In view of such points, the transmission frequency f ₀ is determined from the position higher by 20% of the interval (frequency difference) between adjacent sounds from the lower sound of the average rate scale adjacent to the lower sound. It is desirable to set the frequency between the position 20% below. That is, it is desirable to use the frequency of 60% in the center of the gaps between the sounds of the average rate scale as f ₀ . For example, when it is desired to set the transmission frequency near 12 kHz, f ₀ is set in the gap between the 32nd harmonic (11,840 Hz) of F # in FIG. 3 and the 32nd harmonic of So (12,544 kHz). Since the frequency difference of 704Hz is 11,981Hz, which is 141Hz (704x0.2) above the 32nd harmonic of the lower fa #, and 12,403Hz, which is 141Hz below the 32nd harmonic of the higher So May be set as f ₀ (11,981 <f ₀ <12,403).

Next, how the sound code signal and the source sound are superimposed will be described. FIG. 5 is a conceptual diagram conceptually showing the superimposition of the transmission wave of the sound code and the source sound. In the figure, the horizontal axis indicates frequency, the vertical axis indicates sound pressure, a thick arrow indicates a sound code transmission wave, and a thin arrow indicates a source sound. It is assumed that the source sound is a musical system based on musical instrument performance, and a sound with an average rate scale is output. The transmission wave of the sound code has a transmission frequency f ₀ and its subharmonics, 1/2 f ₀ and 1/3 f ₀ , both of which are located in the gap between the source sounds. Therefore, as will be described later, the sound code can be reliably extracted by filtering the signal in the transmission band of the sound code on the receiving side.

  Next, the data structure of the sound code will be described with reference to FIG. FIG. 6 is a diagram illustrating a data structure of a sound code. The data frame shown in the figure represents a SOF (Start Of File) for identifying the beginning of a file, a data type (type), and a data length (preamble) for synchronizing timing. length) are provided in order. Thereafter, 16 data strings including data1, data2,..., Data7, and CRC (Cyclic Redundancy Code) are provided, and 112 bytes of data can be handled in one frame.

  The type is used for information necessary for identifying the information provider or identifying the transmission frequency of the sound code when the recipient is limited to a specific party. Further, length represents the length of the sound code, and is configured to handle up to 16 frames, that is, 2048 bytes of data shown in the figure.

  The CRC is added for error correction. CRC means a polynomial cyclic code for data error detection and error correction. An error signal code (CRC) is added in advance to outgoing data, and error correction is performed upon reception. Here, error correction is performed by adding a CRC every 7 bytes instead of processing for each frame, and the amount of data can be appropriately changed in units of columns.

The sound code generated in this way is transmitted according to the transmission frequency f ₀ and the timing determined by the masking circuit 105. The transmission time for one frame (1024 bits) at this time is 41.99 ms because f ₀ = 12,192 Hz, and 671.84 ms even for a maximum of 16 frames.

Subsequently, the sound code is received by the D / A conversion circuit 107 at NRZ (Non
Return to Zero) is modulated and converted to an analog signal. At this time, the sound pressure level of the sound code is determined by allocating bits following the detection result of the peak / average detector. The bit size can be set to an arbitrary range, but 10 to 16 bits is appropriate. For example, in the case of 16 bits, the smallest sound pressure level of 0,1 is 0000,0x0001, and the largest sound pressure level is 0000,0xFFFF.

  The sound code converted into an analog signal is cut into a high frequency component by a low-pass filter (LPF) 108 to become a sine wave. The analog signal of the sound code thus shaped is added to the PA source signal in the adding circuit 109, and is transmitted from the speaker. In FIG. 2, “PA source +” indicates that a sound code is superimposed on the PA source signal.

  The processing for generating the sound code described above is realized in software by the calculation means of the transmission device 10 executing an application stored in the storage device, and a dedicated circuit for performing such processing. And may be realized in hardware.

  Next, a process of receiving a sound code in the mobile phone 20 on the terminal side will be described with reference to FIG. FIG. 7 is a block diagram showing a conceptual circuit for realizing the function of receiving a sound code.

  The sound of the PA source on which the sound code is superimposed is picked up by the microphone 21 of the mobile phone 20 and converted into an electrical signal indicated by PA Source + in the figure. This electrical signal first passes through a band pass filter (BPF) 201. The BPF 201 is configured to cut frequencies other than the vicinity of the sound code transmission frequency, and a signal in the vicinity including mainly the sound code component in the PA Source + is sent to the A / D conversion circuit 202. However, since the attenuation of the BPF 201 is low, the process of extracting only the sound code is performed by the sound code extraction circuit 207 described later. The transmission frequency of the sound code can be recognized by referring to the information included in the type of data frame described above, but may be configured to automatically detect and detect on the receiving side.

  The A / D conversion circuit 202 converts the received analog signal into a digital signal. This conversion process is performed at twice (or four times) the speed of the sound code. Subsequently, the phase evaluation circuit 203 checks the phase of the A / D converted signal and corrects all data so as to obtain an optimum value.

  The sub-sampling circuit 204 returns the A / D converted signal to the speed of the transmission frequency of the sound code signal. In the hamming window circuit 205, processing for relatively lowering the signal level at the beginning and end of the signal captured in the frame period is performed. Because the sound code has a frame structure, the superimposed PA source signal is taken in as data cut at the frame period, and many misidentified elements occur at the beginning and end of the frame period. By applying, the influence of both ends can be suppressed.

Subsequently, an FFT (Fast Fourier Transform) circuit 206 performs fast Fourier transform. That is, the received signal on the time axis is converted into a signal on the frequency axis. Then, from a signal on the frequency axis, in a sound code extraction circuit (extract sound code) 207, the frequencies (f ₀ , 1/2 f ₀ , 1/3 f ₀ , Only the signal above 1/4 f ₀ ) is filtered out and converted into a time axis signal in an IFFT (Inverse FFT) circuit 208, whereby the sound code can be restored.

  The transmission frequency of the sound code can be recognized by referring to the information included in the type of data frame described above, but may be configured to automatically detect and detect on the receiving side. In this way, if the extraction is performed by digital processing using the FFT circuit 206 and the sound code extraction circuit 207, only the sound code component can be extracted with high accuracy.

  Although description is omitted in this embodiment, descrambling by the descrambling circuit and error correction by the CRC circuit are also performed on the receiving side. The message is restored from the sound code decoded in this way and displayed on the display 22 of the mobile phone 20. The method of presenting the restored message to the owner of the terminal is not limited to the method of visually displaying on the display, but may be presented by voice from the speaker (not shown) of the mobile phone 20.

  The control / processing for receiving the sound code and restoring the message described above is realized by software by causing the arithmetic means of the mobile phone 20 to execute a predetermined program, but a circuit for realizing a specific function May be installed and realized as hardware.

  The configuration of the information providing system 1 according to the first embodiment has been described above. Next, a procedure for transmitting various information (messages) using the present system will be described.

  First, an information sender who wants to send various information using the information providing system creates a code profile. The code profile can be created by accessing the server 50 via the transmission device 10. In the code profile, a message to be transmitted is registered, and setting values desired by the information sender regarding the timing of transmission, the sound pressure level of the sound code to be transmitted, the transmission frequency, and the like are registered.

The transmission frequency f ₀ is set using the gap of the average rate scale as described above. For example, the transmission timing is 10 times per minute (if the sound code consists of 16 frames, the transmission time per transmission is 671.84 ms as described above). Or, the timing is set such that the transmission is repeated endlessly every 10 seconds.

  Next, when the information sender issues a sound code transmission command to the transmission device 10, the sound code is generated according to the above-described process, and the sound code is transmitted from the speaker 13 of the transmission device 10. At this time, if there is a PA source signal, the sound signal is transmitted with the sound signal superimposed on the PA source sound, and if there is no PA source signal, only the sound code sound signal is transmitted according to the profile data. Is sent.

  Since the sound code according to the present embodiment is transmitted using the gap of the average rate scale of the audible sound band, when the source sound is a music system, the sound code signal and the source sound signal do not overlap. Therefore, it is possible to separate and restore the sound code easily and reliably by applying filtering on the receiving side.

  The owner of the mobile phone who wants to receive the sound code executes a JAVA (registered trademark) or BREW (registered trademark) application for receiving the sound code on the mobile phone 20, so that the sound from the microphone 21 can be received. By picking up the code, various information (messages) transmitted can be displayed on the display 22. When the reception sensitivity of the sound code is low, the sound can be reliably received by changing the direction of the mobile phone 20 so that the microphone 21 is directed toward the speaker 13 or by bringing the mobile phone 20 close to the speaker 13.

  Regarding the transmission of various information using sound codes, it is sufficient to notify customers who have visited the facility by notifying on the bulletin board in the facility or voice announcements. It is also possible to prepare the a cappella jingle in which the sound code is embedded in advance, and to make the presence of the sound code known by periodically flowing the jingle at a predetermined timing. When the sound code message is a URL, the received customer can obtain further information by accessing the homepage using the Internet connection function of the mobile phone.

  According to the information provision system concerning this embodiment, various information can be provided to the customer who visited the facility at low cost using the existing facility. As an information receiving terminal, an existing mobile phone has a built-in microphone for conversation, and it is possible to receive various types of information using sound codes simply by incorporating an application for the information providing system.

  In this embodiment, in order to make the explanation easy to understand, the case where there is one speaker 13 of the transmitting device 10 has been described as an example. However, in the case where it is desired to receive sound codes at a plurality of locations in the facility. A plurality of speakers will be installed.

  In the present embodiment, the sound code is generated by the transmission device installed at the place where the transmission is desired. However, the sound code is created by accessing the server in advance, and the transmission is installed at the site. The apparatus may simply transmit (reproduce) a sound code created in advance at a predetermined timing.

  As described above, the embodiment is most suitable when the source sound is a music system, but can also be applied when there is no source sound or when the source sound is a natural sound. However, if the source sound is a natural sound and there is a source sound that overlaps the transmission frequency of the sound code, the sound pressure level of the sound code is 10 decibels or more (preferably 10 to 15 decibels) than the source sound. If it is transmitted, the sound code can be reliably extracted and restored on the receiving side.

Subsequently, Modification 1 of the present embodiment will be described. In this embodiment, the sound code is NRZ-modulated and transmitted. However, the present modification 1 is different in that analog modulation is performed by differential phase shift keying (DPSK). Here, the DPSK modulation is a method of detecting the phase of the next wave based on the phase of the wave transmitted immediately before. Therefore, if the transmission frequency is f ₀ , f ₀ ± 1/2 f ₀ , F ₀ ± 1/3 f ₀ , upper and lower sidebands having frequencies of ± 1/4 f ₀ are generated.

  Therefore, in the case of NRZ modulation, the transmission wave of the sound code signal and the wave of the source sound are superimposed as shown in FIG. 5, but in the case of DPSK modulation, they are superimposed as shown in FIG. Become. Here, as in FIG. 5, the horizontal axis in FIG. 8 indicates frequency, the vertical axis indicates sound pressure, the thick arrow indicates the transmission wave of the sound code, and the thin arrow indicates the source sound.

Therefore, when adopting DPSK modulation, it is necessary to determine f ₀ so that the transmission frequency f ₀ and its sidebands are located in the gap of the average rate scale shown in FIG. In addition, the sound code extraction circuit on the receiving side filters out the transmission frequency f ₀ and its sidebands f ₀ ± 1/2 f ₀ , f ₀ ± 1/3 f ₀ , ± 1/4 f _0. become.

Then, the modification 2 of this embodiment is demonstrated. In this embodiment, the reception side uses an FFT circuit to extract and restore the sound code by digital signal processing. However, in the second modification, sound is obtained by analog processing using a comb filter (comb filter). The difference is that the code is extracted. The comb filter can be realized by using a delay circuit, and similarly to the case of FFT, the oscillation frequency f ₀ and its subharmonic f ₀ ± 1/2 f ₀ , f ₀ ± 1/3 f ₀ , ± 1/4 it may be configured to extract by filtering the f _0. If the comb filter is used, it is possible to significantly reduce the load on the arithmetic processing in the terminal.

(Second Embodiment)
Next, a second embodiment according to the present invention will be described. The first embodiment is an information providing system configured to transmit a sound code from a speaker connected to a PC. However, in the second embodiment, a sound code (sound pressure vibration) is used for public broadcasting such as television and radio broadcasting. Information) is superposed and broadcast, and the sound code is transmitted as sound pressure vibration from the speaker of the receiver that has received the broadcast radio wave. Hereinafter, description of the configuration common to the first embodiment will be omitted, and different configuration will be described in detail.

  FIG. 9 is a diagram schematically showing the configuration of the information providing system 2 according to the second embodiment. Here, radio broadcasting will be described as an example. As shown in the figure, the information providing system 2 is a broadcasting station 60 that broadcasts a radio program, a broadcast that receives and reproduces broadcast radio waves, and transmits a sound code superimposed on the broadcast radio waves as sound pressure vibrations. A receiver 70 and a mobile phone 20 for receiving sound pressure vibration are provided.

  The broadcasting station 60 includes equipment (not shown) for transmitting broadcast radio waves and a transmission antenna 61, a system for generating a code profile (not shown), and a sound code that is superimposed on the radio waves of program information. It also has a system for broadcasting. The broadcast receiver 70 also includes an antenna 71 for receiving broadcast radio waves and a speaker 72 for reproducing audio information (and sound codes) of broadcast programs.

  In the information providing system 2 having such a configuration, first, program information on which a sound code is superimposed is broadcast from the broadcasting station 60. The code profile is created in accordance with a request from an information provider (such as an advertiser) who desires to transmit a sound code in advance. With reference to the code profile, a sound code generated based on a predetermined transmission timing, sound pressure level, frequency, etc. is superimposed on the program information signal (PA source signal) and broadcasted from the transmission antenna 61 over a wide area. .

  The broadcast receiver 70 that has received the broadcast radio wave on which the sound code is superimposed from the antenna 71 reproduces the audio information of the program from the speaker 72, and at the same time, the audio information of the sound code is also reproduced from the speaker 72, that is, transmitted as sound pressure vibration. .

  Here, in a broadcast program, an announcement is made that a message such as a URL is broadcast as a sound code. The owner of the mobile phone 20 that wants to receive the message activates an application for receiving the sound code, and then directs the microphone 21 of the mobile phone 20 to the speaker 72, so that the sound code is transmitted to the mobile phone via the microphone 21. 20 can be incorporated. The captured sound code is decoded in the mobile phone 20 and a sound code message is displayed on the display 22. It is also possible to prepare the a cappella jingle in which the sound code is embedded in advance, and to make the presence of the sound code known by periodically flowing the jingle at a predetermined timing.

  As described above, the second embodiment has been described in detail. According to the present embodiment, in addition to the operational effects of the first embodiment, the sound code is broadcast over a wide area using public broadcast, and the broadcast is received. It is possible to transmit the sound pressure vibration of the sound code in many places through the machine. Moreover, it is only necessary to add a simple system for superimposing the sound code to the existing broadcasting equipment, and the sound code can be transmitted over a wide area with a small capital investment.

  In addition, according to the present embodiment, it is possible to effectively use the character information or the like that cannot be conveyed in the program to convey to the viewer. In addition, if URL information is sent as a sound code in order to make it easy for viewers to access the homepage of a program or the homepage of a sponsor, it can be effectively used as an advertising medium.

  In the present embodiment, the case where the information providing system 2 is applied to terrestrial radio is described as an example. However, the information providing system 2 may be applied to terrestrial television, and not only terrestrial broadcasting but also cable television or the like. The present invention may be applied to satellite broadcasting such as cable broadcasting, CS broadcasting, and BS broadcasting.

  As mentioned above, based on 1st and 2nd embodiment, although the information provision system which concerns on this invention was demonstrated, according to this information provision system, as a transmission frequency of a sound code, a transmission frequency and its subharmonic frequency are average. Since frequencies that are located in the gaps between each sound in the scale are used, if the source sound is a music sound, the frequency of the sound code signal and the frequency of the source sound will not overlap. The sound code can be reliably separated and restored on the receiving side.

  The embodiment of the present invention is not limited to the first and second embodiments described above, and various modifications can be made without departing from the spirit of the present invention. For example, the format structure of the sound code can be changed as appropriate, and it goes without saying that the error correction method and the encoding method can be set freely as appropriate.

  The terminal on the receiving side is not limited to a mobile phone, and any terminal provided with a microphone may be used. For example, it may be a PDA, an IC recorder, a portable radio, a portable television, a notebook computer, a radio cassette, a game machine, or the like. In addition, a dedicated terminal for applying the present invention may be provided.

  Moreover, even if the terminal on the receiving side is a terminal that does not have a display, it is sufficient if it is provided with a speaker, and the owner of the terminal can be notified by reproducing various information by voice. Further, the terminal is not limited to a portable terminal, and may be a stationary terminal as long as the terminal includes a microphone for picking up sound of a sound code.

  In addition, the code profile is not limited to the one created by accessing the server, but the application for creating the code profile is installed on the user's PC, and the code profile is created using the PC. May be. Further, instead of creating a chord profile in advance, each parameter may be set on the spot when generating a sound code.

FIG. 1 is a diagram schematically showing a configuration of an information providing system according to the first embodiment. FIG. 2 is a block diagram showing a conceptual circuit for realizing the function of generating a sound code. FIG. 3 is a diagram showing the frequency of each sound of the average rate scale. FIG. 4 is a diagram illustrating a transmission frequency and a subharmonic frequency according to the first embodiment. FIG. 5 is a diagram illustrating a state of superimposing the sound code signal and the source sound according to the first embodiment. FIG. 6 is a diagram illustrating a data structure of a sound code. FIG. 7 is a block diagram showing a conceptual circuit for realizing the function of receiving a sound code. FIG. 8 is a diagram illustrating a state of superimposition of the sound code signal and the source sound according to the first modification of the first embodiment. FIG. 9 is a diagram schematically illustrating a configuration of an information providing system according to the second embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 2 Information provision system 10 Transmission apparatus 11 Display 12 Keyboard 13 Speaker 14 PC main body 20 Mobile phone 21 Microphone 22 Display 40 Internet 50 Server 60 Broadcast station 61 Transmitting antenna 70 Broadcast receiver 71 Antenna 72 Speaker

Reference Signs List 101 A / D conversion circuit 102 Frame division circuit 103 Peak / average detector 104 Rising detector 105 Masking circuit 106 Code generation circuit 107 D / A conversion circuit 108 Low-pass filter 109 Addition circuit 201 Band-pass filter 202 A / D conversion circuit 203 Phase evaluation circuit 204 Sub-sampling circuit 205 Hamming window circuit 206 FFT circuit 207 Sound code extraction circuit 208 IFFT circuit

Claims (6)

A transmission device that converts various types of encoded information into sound pressure vibrations that use the frequency of each sound gap in the average rate scale within the audible sound range,
A terminal that receives and decodes the sound pressure vibration to restore the various information, and has a filtering means for filtering the transmission frequency of the transmission device and the vicinity of the sub-harmonic or sideband frequency. And comprising
Information is transmitted from the transmitting device to the terminal as sound using air as a medium.   2. The information providing system according to claim 1, wherein the oscillation frequency of the oscillation device and the frequency of the subharmonic or sideband thereof is a frequency of the gap of the average rate scale.   3. The information providing system according to claim 1, wherein the oscillation device is a device that uses a frequency of 60% in the center of the gap of each sound of the average rate scale to generate a transmission frequency. 4. A transmitting device for transmitting various information to a terminal in an information providing system,
Arithmetic means for encoding various information;
A speaker for converting and transmitting the encoded various information to sound pressure vibrations using a frequency of a gap of each sound of an average rate scale in the audible sound range, and air to the terminal A transmission device characterized in that information is transmitted as sound using a medium as a medium. An information providing method for providing various information to a terminal,
An encoding process for encoding various information;
A transmission step of transmitting the encoded various information by converting into sound pressure vibration using the frequency of the gap of each sound of the average rate scale in the audible range,
A receiving step of receiving the sound pressure fluctuation at a terminal;
A restoration step of decoding the sound pressure vibration while filtering a frequency near the frequency of the transmission step and the subharmonic or sideband in the terminal and restoring the various information. Information provision method. Broadcasting equipment that broadcasts TV, radio, etc.
Arithmetic means for encoding various information and superimposing it on a broadcast signal;
A transmission antenna for transmitting the broadcast signal as a radio wave,
When the broadcast signal on which the encoded various information is superimposed is received and reproduced by the broadcast receiver, the encoded various information superimposed on the broadcast signal is transmitted from the speaker of the broadcast receiver. A broadcasting facility characterized in that it is a signal configured to be transmitted after being converted into a sound pressure vibration using a frequency of a gap of each sound of an average rate scale in an audible sound range.

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