KR102402706B1 - System for Sound Tag Using Ultra Directional Speaker and The speaker - Google Patents

Abstract

The present invention provides a super directional speaker for modulating a sound tag including information on a carrier wave in an ultrasonic region, and a receiving terminal for receiving a modulated signal transmitted from the super directional speaker, and analyzing and processing sound tag information included in the signal. A sound tag system using a super directional speaker comprising: a signal amplifying unit for amplifying a signal to be transmitted; A transmission data generator for generating transmission data by bandspreading sound tag information including information into codes having orthogonality, a digital summer for summing the transmission data, and a signal modulator for modulating the combined transmission data by fusing it with an ultrasonic carrier wave Transmission signal processing unit including; a frequency combination unit for combining a frequency domain to include the sound tag; and a signal transmitting unit for transmitting the signal generated by the signal modulating unit or the frequency combining unit to a receiving terminal, wherein the receiving terminal includes: a signal receiving unit for receiving a modulated signal including a sound tag from a super directional speaker; a signal analysis unit for extracting a sound tag area containing information from the received signal; and a signal processing unit for controlling a device of a receiving terminal according to the information analyzed by the signal analysis unit.

Description

System for Sound Tag Using Ultra Directional Speaker and The speaker

The present invention relates to a sound tag system using a super directional speaker and a speaker used therein, and more particularly, to a sound tag system using a super directional speaker with directivity, communication distance expansion, and integrity secured.

The content described in this section merely provides background information for the present embodiment and does not constitute the prior art.

In sound communication technology, sound wave communication technology refers to a technology that transmits digital information in a sound in a high frequency band that humans cannot hear. As the frequency of sound increases, it becomes inaudible to the human ear, so the high-frequency sound is used like Morse code to transmit information. With this sound wave communication technology, devices can send and receive information without disturbing people.

When sound wave communication technology is used, when music with sound codes is played on TV or radio, the mobile phone recognizes the sound and automatically shows singer information, lyrics, MP3 storage, etc. You can receive it from your mobile phone and provide related services. Also called sound code, sound tag or voice barcode technology.

The sound wave communication technology according to the prior art is better than the electromagnetic wave, but it spreads widely in a closed space and has a transmission characteristic.

In addition, the sound wave communication technology according to the prior art uses low-frequency ultrasonic waves (18 to 20 KHz) in the audible region, artificial sound such as music is treated as noise in sound wave communication, and complex frequency patterns (such as Chirp) are used for noise immunity. This is necessary, and BPS (Bit Per Second) performance decreases.

In addition, the sound wave communication technology according to the prior art can communicate only in the air over a short distance, and spatial security issues and unnecessary communication triggers occur.

Accordingly, in the present invention, it is intended to propose a sound tag system using a super directional speaker capable of resolving the above-described technical limitations.

Korean Patent Registration No. 10-0622078, published on September 1, 2006 (Title: Supercardioid speaker system and signal processing method) Korean Patent Registration No. 10-1074431, published on October 11, 2011 (Name: Supercardioid Ultrasonic Speaker System) Korean Patent Application Laid-Open No. 10-2019-0110275, published on September 30, 2019 (Title: Acoustic event detection method using directional microphone, and acoustic event detection device using directional microphone)

The present invention has been proposed to solve the problems of the prior art, and a main object of the present invention is to provide a sound tag system using a super directional speaker capable of transmitting even a small sound far and strong against noise.

Another object of the present invention is to provide a sound tag system using a super directional speaker that enables communication to a specific spatial area through the directivity range of ultrasonic waves.

Another object of the present invention is to provide a sound tag system using a super directional speaker that enables setting of a communication area (short-distance, medium-distance, long-distance, etc.) through parameterization such as transmission carriers.

The problems to be solved of the present invention are not limited to those mentioned above, and other problems to be solved that are not mentioned will be clearly understood by those of ordinary skill in the art to which the present invention belongs from the following description.

The technical problem of the present invention as described above is achieved by the following means.

(1) a super directional speaker that modulates a sound tag including information on a carrier wave in the ultrasonic region, and a receiving terminal that receives a modulated signal transmitted from the super directional speaker, analyzes and processes the sound tag information included in the signal; In the sound tag system using a super directional speaker comprising:

A supercardioid speaker modulating the sound tag,

a signal amplifier for amplifying a signal to be transmitted; A transmission data generator for generating transmission data by bandspreading sound tag information including information into codes having orthogonality, a digital summer for summing the transmission data, and a signal modulator for modulating the combined transmission data by fusing it with an ultrasonic carrier wave Transmission signal processing unit including; a frequency combination unit for combining a frequency domain to include the sound tag; and a signal transmitting unit for transmitting the signal generated by the signal modulating unit or the frequency combining unit to a receiving terminal,

The receiving terminal is

a signal receiving unit for receiving a modulated signal including a sound tag from the super directional speaker; a signal analysis unit for extracting a sound tag area containing information from the received signal; and a signal processing unit for controlling a device of a receiving terminal according to the information analyzed by the signal analysis unit.

(2) In the above (1), the transmission signal processing unit,

A sound tag system using a super directional speaker, characterized in that it includes at least three channels for spreading the sound tag transmission data including information and a channel for spreading one checksum data.

(3) The transmission data generation unit according to (1) or (2) above,

Sound tag using a super directional speaker, characterized in that it further comprises a data multiplier for generating transmission data by multiplying first data generated by spreading the sound tag transmission data including information and second data different from the first data system.

(4) The sound tag included in the transmission signal processing unit according to (1) above,

A sound tag system using a supercardioid speaker, characterized in that it modulates data through the inaudible range of 18kHz to 20kHz or the inaudible range of 20kHz to 22kHz.

(5) in (1) above, the frequency combination unit,

A sound tag system using a super directional speaker, characterized in that it combines the frequencies of the normal audible range of 20Hz to 18kHz and the inaudible range of 18kHz to 20kHz.

(6) The frequency combination unit according to (1) above,

A sound tag system using a super directional speaker, characterized in that it combines the frequencies of the inaudible range of 18kHz to 20kHz and the inaudible range of 20kHz to 22kHz.

(7) In the above (1), the signal analysis unit,

A sound tag system using a super directional speaker, characterized in that it filters other frequency regions and analyzes only the sound tags in the 20 kHz to 22 kHz region.

(8) a signal amplifier for amplifying a signal to be transmitted;

A transmission data generator for generating transmission data by bandspreading sound tag information including information into codes having orthogonality, a digital summer for summing the transmission data, and a signal modulator for modulating the combined transmission data by fusing it with an ultrasonic carrier wave Transmission signal processing unit including;

a frequency combination unit for combining a frequency domain to include the sound tag; and

and a signal transmitting unit for transmitting the signal generated by the signal modulator or the frequency combination unit to a receiving terminal.

(9) In the above (8), the transmission signal processing unit,

A supercardioid speaker for a sound tag system, comprising at least three channels for spreading the sound tag transmission data including information and a channel for spreading one checksum data.

(10) The transmission data generation unit according to (8) or (9) above,

Supercardioid speaker for sound tag system, characterized in that it further comprises a data multiplier for generating transmission data by multiplying first data generated by spreading the sound tag transmission data including information and second data different from the first data. .

According to the sound tag system using the super directional speaker of the present invention, there is an effect that it is possible to provide a sound tag system using the super directional speaker that can transmit even a small sound far and is strong against noise.

In addition, there is an effect that it is possible to provide a sound tag system using a super-directional speaker that enables communication to a specific spatial area through the directivity range of ultrasonic waves.

In addition, there is an effect that it is possible to provide a sound tag system using a super directional speaker that enables communication area setting (short-distance, medium-distance, long-distance, etc.) through parameterization such as transmission carrier.

The effects obtainable in the present invention are not limited to the above-mentioned effects, and other effects not mentioned will be clearly understood by those of ordinary skill in the art to which the present invention belongs from the following description. .

BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are included as a part of the detailed description to facilitate the understanding of the present invention, provide embodiments of the present invention, and together with the detailed description, explain the technical features of the present invention.
1 is a diagram illustrating a transmission/reception frequency domain of a sound wave communication system according to the prior art.
2 is a diagram illustrating the configuration of a sound tag system using a supercardioid speaker according to an embodiment of the present invention.
3 is a diagram illustrating a frequency domain of a sound tag system using a super directional speaker according to an embodiment of the present invention.
4 is a diagram illustrating a configuration of a supercardioid speaker according to an embodiment of the present invention.
5 is a diagram illustrating the configuration of a receiving terminal according to an embodiment of the present invention.
6 is an overall configuration diagram of a sound tag system using a super directional speaker as a preferred embodiment of the present invention.
7 is a diagram showing a shape of a signal waveform on the transmission side according to an embodiment of the present invention.
8 is a diagram showing a signal waveform of a reception side according to an embodiment of the present invention.

Hereinafter, preferred embodiments according to the present invention will be described in detail with reference to the accompanying drawings. DETAILED DESCRIPTION The detailed description set forth below in conjunction with the appended drawings is intended to describe exemplary embodiments of the present invention and is not intended to represent the only embodiments in which the present invention may be practiced. The following detailed description includes specific details in order to provide a thorough understanding of the present invention. However, one of ordinary skill in the art to which the present invention pertains will recognize that the present invention may be practiced without these specific details.

In some cases, well-known structures and devices may be omitted or shown in block diagram form focusing on core functions of each structure and device in order to avoid obscuring the concept of the present invention.

Throughout the specification, when a part is said to "comprising or including" a certain component, it does not exclude other components unless otherwise stated, meaning that other components may be further included. do. In addition, terms such as “…unit”, “…group”, and “module” described in the specification mean a unit that processes at least one function or operation, which may be implemented as hardware or software or a combination of hardware and software. have. Also, "a or an", "one", "the" and like related terms are used differently herein in the context of describing the invention (especially in the context of the following claims). Unless indicated or clearly contradicted by context, it may be used in a sense including both the singular and the plural.

In describing the embodiments of the present invention, if it is determined that a detailed description of a well-known function or configuration may unnecessarily obscure the gist of the present invention, the detailed description thereof will be omitted. In addition, the terms to be described later are terms defined in consideration of functions in an embodiment of the present invention, which may vary according to intentions or customs of users and operators. Therefore, the definition should be made based on the content throughout this specification.

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

1 is a diagram illustrating a transmission/reception frequency domain of a sound wave communication system according to the prior art.

The data transmission method using sound according to the prior art transmits sound in the audible region through sound wave transmission/reception in a human-centered sound environment.

The frequency of the human hearing range is 20 Hz to 20 kHz. The reproducible frequency of a typical smartphone speaker is 20Hz ~ 20KHz, and the available frequency of a smartphone microphone is 20Hz ~ 22KHz.

In the existing sound wave communication system, data was transmitted and received at 18 kHz to 20 kHz, which is a region that is difficult to hear among the audible region, mainly near ultrasonic.

However, there is a problem in the prior art that the recognition rate is lowered because there are various sounds in the audible range of 18 kHz to 20 kHz, and there is a lot of noise other than the data of the sound tag.

2 is a diagram illustrating the configuration of a sound tag system using a supercardioid speaker according to an embodiment of the present invention.

The system according to an embodiment of the present invention transmits a modulated (ultrasonic region, for example, 20 to 22 kHz) sound by using an ultrasonic super directional speaker instead of a speaker of a general audible frequency band, and a sound tag capable of receiving the sound in the audible region ( data) transmission.

The super directional speaker 100 is a speaker made so that the sound can be heard only in a specific area by aiming and sending the sound like light, and has an infinite range of applications such as exhibition halls and bus stops, as well as a guide system for the visually impaired. The super directional speaker 100 is a special purpose speaker that modulates a sound signal and then loads and transmits the ultrasonic signal. The sound transmission distance is up to 300m, which is much longer than that of general speakers.

Ultrasound is a type of acoustic vibration and refers to sound waves that exceed the range that humans can hear. The range of hearing varies from person to person, but the frequency that the average person can hear is about 20Hz to 20kHz. Therefore, in ultrasonic technology, sound waves with a frequency of 20 kHz or higher are usually called ultrasonic.

Ultrasound is completely inaudible because it is in a frequency range that is outside the human audible range. However, when an ultrasonic beam passes through space, the ultrasonic wave has a property of being distorted in a predictable direction due to the intrinsic properties (non-linearity) of the space. This distortion can be changed to a frequency component of the audible band, and if it is accurately predicted and precisely adjusted, it can be used as the supercardioid speaker 100 .

The supercardioid speaker 100 is a device for reproducing an audio signal in an audible band from ultrasonic waves in an audible band or higher, and is a high-tech sound device by combining ultrasonic waves and sound waves.

The straightness of the ultrasonic wave, the flat frequency band characteristic of the ultrasonic transducer, and the acoustic energy conversion are highly efficient, and there is no deterioration in sound quality due to harmonics. In addition, there is no limit to the low frequency reproduction band due to mechanical resonance as in the conventional speaker, and since an enclosure is unnecessary as a speaker system, it is possible to improve the sound quality, improve the band characteristics, and achieve high efficiency compared to the conventional speaker system. In addition, it can be applied to various IT fields because it has the advantage of easily generating the entire audible sound range and the orientation in a specific direction is very large.

The super directional speaker 100 needs not only the function of a general speaker but also an additional function for digital modulation and amplification into the ultrasonic region to be mounted in the amplifier.

The receiving terminal 200 is a device that receives the signal transmitted from the super directional speaker 100 and extracts the sound tag included in the signal, and is typically a smartphone, but can process information with a built-in microphone All information and communication devices, desktop, tablet PC, notebook, net book, multimedia terminal, wired terminal, fixed terminal, IP (Internet Protocol) terminal, mobile phone, PMP ( Portable Multimedia Player), MID (Mobile Internet Device), etc. may be any type of information communication device.

3 is a diagram illustrating a frequency domain of a sound tag system using a super directional speaker according to an embodiment of the present invention.

The supercardioid speaker 100 according to the present invention uses a frequency of the inaudible region (20 kHz or higher) as a carrier wave (eg, 40 kHz), unlike a general speaker, and the receiving terminal 200 is a smart phone, in the case of a microphone, a sound pickup region is 20-22 kHz.

In FIG. 3, 18 kHz to 20 kHz and 20 kHz to 22 kHz bands are used as a sound tag area in the super directional speaker 100, and 40 kHz is shown as a carrier wave.

In addition, although FIG. 3 illustrates a double-sideback modulation (DSB) method or a vestigial sideband (VSB) method, single-sideback modulation (SSB) is not excluded.

In the supercardioid speaker 100, modulation consists of a signal carrier for conveying information, the amplitude of the carrier wave, and an information signal having information (Message Signal).

When the amplitude-modulated signal is Fourier-transformed and viewed in the frequency domain, the upper and lower sidebands of the same shape are generated by frequency shifting up and down by the carrier frequency.

Among the various modulation techniques, when the amplitude of the carrier wave is proportional to the information signal, the technique of transmitting information on both the Upper SideBand and the Lower SideBand is called Double Sideback Modulation (DSB).

SSB (Single Sideback Modulation) is a method of transmitting only one sideband among the upper sideband or the lower sideband on the spectrum.

VSB (Vestigial Sideband) Among amplitude modulation methods, unlike SSB, it is a modulation method that does not completely remove one sideband, but leaves a part of it and removes the rest.

In the microphone of the receiving terminal 200, there is no significant difference between the sound tag method and the conventional sound tag method in the audible region (18 to 20 kHz) and near ultrasonic region of the general sound tag. However, there is a lot of noise of general audible sound in this area.

When the method according to an embodiment of the present invention is used, the speed and reliability are improved when filtering is performed for other regions and data is acquired for the region of 20 kHz to 22 kHz.

In FIG. 3, both the cases of sound absorption in the ultrasonic proximity region ((18 kHz to 20 kHz) and the inaudible region (20 kHz to 22 kHz) are illustrated.

4 is a diagram illustrating the configuration of a supercardioid speaker according to an embodiment of the present invention.

The signal amplification unit 110 amplifies the output of the signal, and the transmission signal processing unit 120 spreads the sound tag information including the information into a code having orthogonality, and transmits the sound tag information to a carrier wave (eg, 20 to 40 kHz). It is fused so that it can be loaded and sent.

In the sound tag transmission method according to the present invention, data can be transmitted in the frequency domain below.

1. 20Hz ~ 18kHz: Transmits audible data using normal audible range (heard data)

2. 18kHz ~ 20kHz: Transmits data to the audible area that is hard to hear

3. 20kHz ~ 22kHz: Transmits data in the audible area

4. Paragraphs 1 & 2 above, or a combination of items 2 & 3

In FIG. 3, only methods 2 and 3 are shown among the above 4 methods.

The frequency combination unit 130 expands the data transmission frequency range by combining the above methods as necessary to improve speed and reliability.

The signal transmitting unit 140 transmits the modulated or combined signal to the receiving terminal 200 .

On the other hand, among the latest smart phones, there is a phone equipped with a speaker capable of playing up to 22 kHz. When this function is implemented, the transmission signal processing unit 120 is omitted, so that bidirectional communication (sound tag) in the 20 kHz to 22 kHz band without additional hardware is implemented. It is also possible to

5 is a diagram illustrating the configuration of a receiving terminal according to an embodiment of the present invention.

The signal receiving unit 210 receives the modulated signal transmitted from the signal transmitting unit 140 of the super directional speaker 100 .

The received signal processing unit 220 extracts a portion containing information, ie, a sound tag area, from among the received modulated signals. Acquisition in the audible region and near ultrasonic region of a general sound tag is not much different from the existing sound tag method. Acquisition of data in the 22kHz region improves speed and reliability.

The device control unit 230 drives other devices of the receiving terminal, for example, a display, a speaker, and a communication unit, according to the information analyzed by the received signal processing unit 220 to process and process the information.

When the receiving terminal 200 is a smart device, the signal receiving unit 210 may utilize the microphone of the receiving terminal 200 . In addition, the received signal processing unit 220 and the device control unit 230 may be implemented as a function of an application program (app, App) that is activated or driven in the background.

6 is an overall configuration diagram of a sound tag system using a super directional speaker as a preferred embodiment of the present invention.

In the sound tag system according to the embodiment, the transmission signal processing unit 120 includes a transmission data generation unit 122 , a transmission-side digital summer 124 , and a signal modulator 126 .

The transmission data generator 122 further includes a bandwidth spreader 122a and, if necessary, a data multiplier 122b.

Each of the three data streams d ₁ , d ₂ , and d ₃ is generated by the orthogonal code blocks (c ₁ , c ₂ ), (c ₂ , c ₃ ), (c ₄ , c ₅ ) in the spreader 122a, respectively. The bandwidth is spread to generate c _i , c _j , c _k , which are transmission data, respectively. In this case, each of c _i , c _j , and c _k is also another orthogonal code.

If necessary, in a preferred embodiment of the present invention, a data multiplier 122b is provided at the rear end of the spreader _122a , and additional data _strings d ₄ , _{d 5} , By multiplying each d ₆ , new transmission data c _i ·d ₄ , c _j ·d ₅ , and c _k ·d ₆ can be generated to greatly improve transmission efficiency.

In the embodiment of the present invention, d ₇ =d ₁ ·d ₂ ·d ₃ is used as checksum data for detecting an error in the data transmission process. In this case, cl=c _i ·c is an orthogonal code for spreading the checksum data. _j ·c _k is used. Similarly, checksum data may be added, and in this case, d ₈ =-d ₄ ·d ₅ ·d ₆ is used for the added checksum data.

Transmission data generated through the above process is summed by the transmitting-side digital summer 124 , and is transmitted through the signal transmitting unit 140 after being modulated by the signal modulating unit 126 .

In addition, the reception signal processing unit 220 of the sound tag system according to the embodiment includes a signal demodulation unit 222 , a despreading unit 224 , a reception side digital summer 226 , and a data extraction unit 228 . The data extraction unit 228 further includes a first data extraction unit 228a and a second data extraction unit 228b if necessary.

The data demodulated by the signal demodulation unit 222 is multiplied by each orthogonal code (c ₁ , c ₂ , c ₃ , c ₄ , c ₅ , c ₆ ) in the despreading unit 224 and despreaded to form six data streams. is output as d ₁ , d ₂ , and d ₃ as original data from the first data extraction unit 228a through the receiving-side digital summer 226 . At this time, if the additional data strings d ₄ , d ₅ , d ₆ are added during transmission, there are two sound tags such as (d ₁ , d ₄ ), (d ₂ , d ₅ ), (d ₃ , d ₆ ). The six data d ₁ , d ₂ , d ₃ , d ₄ , d ₅ , d that are output in a form including information and initially transmitted through the first data extraction unit 228a and the second data extraction unit 228b ₆ are printed respectively. Preferably, the first data extraction unit 228a outputs d ₁ , d ₂ , and d ₃ as a method of finding the maximum value, respectively, and the second data extraction unit 228b finds the polarity d ₄ , d ₅ and d ₆ are printed.

A signal waveform obtained for each step through the above process is shown in FIGS. 7 (transmitting side) and 8 (receiving side), respectively.

As described above, according to the present invention, according to the sound tag system using the super directional speaker, it is possible to provide a sound tag system using the super directional speaker capable of transmitting even a small sound far and being strong against noise.

Combinations of each block in the block diagram attached to this specification and each step in the flowchart may be performed by computer program instructions. These computer program instructions may be embodied in a processor of a general-purpose computer, special purpose computer, or other programmable data processing equipment, such that the instructions executed by the processor of the computer or other programmable data processing equipment may be configured in the respective blocks of the block diagram or of the flowchart. Each step creates a means for performing the described functions. These computer program instructions may also be stored in a computer-usable or computer-readable memory that may direct a computer or other programmable data processing equipment to implement a function in a particular manner, and thus the computer-usable or computer-readable memory. The instructions stored in the block diagram may also produce an item of manufacture containing instruction means for performing a function described in each block of the block diagram or each step of the flowchart. The computer program instructions may also be mounted on a computer or other programmable data processing equipment, such that a series of operational steps are performed on the computer or other programmable data processing equipment to create a computer-executed process to create a computer or other programmable data processing equipment. It is also possible that instructions for performing the processing equipment provide steps for carrying out the functions described in each block of the block diagram and in each step of the flowchart.

Further, each block or each step may represent a module, segment, or portion of code comprising one or more executable instructions for executing specified logical function(s). It should also be noted that in some alternative embodiments it is also possible for the functions recited in blocks or steps to occur out of order. For example, it is possible that two blocks or steps shown one after another may in fact be performed substantially simultaneously, or that the blocks or steps may sometimes be performed in the reverse order according to the corresponding function.

The above description is merely illustrative of the technical spirit of the present invention, and various modifications and variations will be possible without departing from the essential characteristics of the present invention by those skilled in the art to which the present invention pertains. Accordingly, the embodiments disclosed in the present invention are not intended to limit the technical spirit of the present invention, but to explain, and the scope of the technical spirit of the present invention is not limited by these embodiments. The protection scope of the present invention should be construed by the following claims, and all technical ideas within the equivalent range should be construed as being included in the scope of the present invention.

According to the sound tag system using the super directional speaker of the present invention, a sound tag system using a super directional speaker is provided, which provides a sound tag system using a super directional speaker that is strong against noise and can transmit even a small sound to have directivity far away. In the sense that it can be used as a solution that can be used as a solution for It's a potential invention.

100: super directional speaker 120: transmit signal processing unit 130: frequency combination unit
140: signal transmitting unit 200: receiving terminal 210: signal receiving unit
220: reception signal processing unit 230: device control unit

Claims (10)

A second comprising a super directional speaker for modulating a sound tag including information on a carrier wave in the ultrasonic region, and a receiving terminal for receiving a modulated signal transmitted from the super directional speaker, and analyzing and processing sound tag information included in the signal A sound tag system using a directional speaker, comprising:
A supercardioid speaker modulating the sound tag,
a signal amplifier for amplifying a signal to be transmitted; A transmission data generator for generating transmission data by bandspreading sound tag information including information into codes having orthogonality, a digital summer for summing the transmission data, and a signal modulator for modulating the combined transmission data by fusing it with an ultrasonic carrier wave Transmission signal processing unit including; a frequency combination unit for combining a frequency domain to include the sound tag; and a signal transmitting unit for transmitting the signal generated by the signal modulating unit or the frequency combining unit to a receiving terminal,
The receiving terminal is
a signal receiving unit for receiving a modulated signal including a sound tag from the super directional speaker; a signal analysis unit for extracting a sound tag region containing information among the modulated signals received by the signal receiving unit; and a signal processing unit for controlling the device of the receiving terminal according to the information analyzed by the signal analysis unit,
The transmission signal processing unit,
at least three channels for spreading sound tag transmission data including information and a channel for spreading one checksum data;
The transmission data generation unit,
and a data multiplier configured to generate transmission data by multiplying first data generated by spreading the sound tag transmission data including information and second data different from the first data,
The sound tag included in the transmission signal processing unit,
It modulates data through the inaudible region of 18 kHz to 20 kHz or the inaudible region of 20 kHz to 22 kHz,
The frequency combination unit,
A sound tag system using a supercardioid speaker, characterized in that it combines the frequencies of the inaudible region of 18 kHz to 20 kHz and the inaudible region of 20 kHz to 22 kHz.
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