KR101462472B1 - Masage Tranfering System and Method Using the Sound Wave Signal - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information delivery system using a sound signal.
In the information transmission method using the sound wave signal according to the present invention, a sound wave signal generator converts digital data into a sound wave signal in a frequency band of 17 KHz to 25 KHz, wherein the sound wave signal generator generates sound waves corresponding to the high signal period and the low signal period, Generating a sound wave signal to include a valid data signal that does not output or output the sound wave signal; The receiving terminal receiving the sound wave signal; The receiving terminal reconstructing the sound wave signal into digital data; And performing a signal processing of the digital data by the receiving terminal.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a system and method for transmitting information using a sound wave signal,

The present invention relates to an information delivery system and method using an acoustic signal, and more particularly, to an information delivery system and method using an acoustic signal that can transmit information to a large number of users without requiring a large-scale infrastructure.

Communication for information transmission includes wired communication using an optical cable or a wired network, and wireless communication not using an optical cable or a wireless network. Wired communication is a reliable communication means because it is less likely to lose or lose information in the course of information transmission, but it has a disadvantage in that it takes a lot of time and cost to install a wired network.

Wireless communication is relatively less infrastructural than wired communication and has the advantage of not harming aesthetics due to wired network. In addition, since the portable terminal can be used, the frequency and use of wireless communication have been increasing rapidly in recent years. Such wireless communication has a main purpose of communication of voice information, such as wireless mobile communication or satellite phone, and communication mainly for data communication such as wireless Internet or WiBro.

In general wireless communication, a high frequency or a high frequency radio frequency is used, and each wireless communication has a specific frequency band for each communication company or terminal in order to prevent problems caused by mixed use of frequencies.

In other words, wireless communication requires a certain infrastructure, because it requires the prescribed protocol and regulations between terminals and communication companies using such a protocol, and the application range is also limited by such a disadvantage.

In order to improve the disadvantages of such a large-scale infrastructure and to transmit a small amount of information at a short distance, a one-way information transmission method is used through scanning of bar codes and the like. However, this information transmission method requires a separate communication equipment such as a barcode reader, and thus is not used as an information delivery means for an unspecified number of ordinary people.

Therefore, in the conventional wireless communication, there is a need to provide a new communication means that does not require a huge infrastructure in order to transmit near information by targeting an unspecified number of persons.

SUMMARY OF THE INVENTION Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and it is an object of the present invention to provide an information delivery system and method using an acoustic signal that can efficiently transmit information to a large number of users without requiring a large- There is a purpose.

In order to solve the above-mentioned problems, in the information transmission method using the sound wave signal according to the present invention, a sound wave signal generator converts digital data into a sound wave signal in a frequency band of 17 KHz to 25 KHz, Generating a sound wave signal so as to include a valid data signal that outputs or does not output a sound wave corresponding to a low signal interval; The receiving terminal receiving the sound wave signal; The receiving terminal reconstructing the sound wave signal into digital data; And performing a signal processing of the digital data by the receiving terminal.

The generating of the sound wave signal includes generating a valid data signal including a start signal and an end signal in which the pattern is stored in the receiving terminal in advance, Generating a verification signal for storing a pattern in a receiving terminal in advance and distinguishing a valid data signal from an external noise; And combining the valid data signal and the verify signal.

The generating of the valid data signal may include generating a valid data signal to output a sound wave corresponding to a high signal interval of the digital data and not outputting a sound wave corresponding to a low signal interval of the digital data.

The step of reconstructing the sound wave signal into digital data includes filtering the sound wave received by the microphone of the receiving terminal with a sound wave having the same frequency as the validation signal and the valid data signal and separating the sound wave into first and second sound waves, respectively. Converting each of the first and second sound waves to generate a first digital signal and a second digital signal; Determining a first sound wave as a verification signal when the first digital signal is the same as a preset verification signal pattern; Determining a second sound wave as an effective data signal when the start signal of the second digital signal corresponding to the start signal section of the first digital signal is the same as the start signal pattern of the preset valid data signal; And extracting digital data between the start signal and the end signal in the second digital signal in which the valid data signal is modified, and performing signal processing of the digital data.

And generating the sound wave signal may be to convert the digital data, which is an ASCII code, into a valid data signal.

The information transmission system according to the present invention comprises: a sound wave signal generator for converting digital data into sound wave signals including sound waves in a frequency band of 17 KHz to 25 KHz to send sound wave signals to the outside; And a receiving terminal for receiving a sound wave signal transmitted from the sound wave signal generator and for converting a section in which a sound wave is outputted or not outputted into a high signal and a low signal respectively to restore digital data and perform signal processing of digital data, , The sound wave signal generator generates a sound wave signal including an effective data signal that divides the binary signal of the digital data into a section in which the sound wave is outputted or not outputted.

Wherein the sound wave signal generator comprises: a valid data signal including a start signal and an end signal in which a pattern is previously set and stored in a receiving terminal; A pattern is stored in the receiving terminal in advance, and a verification signal for distinguishing the valid data signal from the external noise is synthesized to generate a sound wave signal.

The sound wave signal generator outputs a sound wave corresponding to a section in which the digital data outputs a high signal and generates an effective data signal so that the sound wave is not outputted in response to the section in which the digital data outputs the low signal.

The receiving terminal further includes a memory for storing a valid data signal pattern and a verification signal pattern; A microphone for receiving sound waves; A first filter unit for separating a first sound wave by filtering a sound wave having the same frequency as a verification signal in a sound wave; A second filter unit for filtering the sound wave having the same frequency as the effective data signal in the sound wave to separate the second sound wave; First and second digital conversion units for respectively converting first and second sound waves output from the first and second filter units to generate first and second digital signals; And a control unit for checking the start signal of the effective data signal in the section corresponding to the start signal of the verify signal when the first digital signal outputted from the first digital converter is the same as the verify signal pattern stored in the memory, And a control unit for processing the data signal between the start signal and the end signal as digital data.

According to the information transmission method using the sound wave signal according to the present invention, wireless communication can be performed through a simple configuration without passing through a communication company or a wireless repeater. That is, the method for transmitting information using the sound wave signal according to the present invention can be performed by using a conventional infrastructure or a simple additional configuration because the sound wave signal is transmitted and received using a speaker and a microphone.

In particular, since the information transmission method using the sound wave signal according to the present invention can use a portable terminal such as a smart phone as a receiving terminal, many users can be used.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a view showing an information delivery system using sound waves according to the present invention; FIG.
2 is a block diagram showing the configuration of an information delivery system using an acoustic signal according to the present invention;
3 is a flowchart showing an information transmission method using a sound wave signal according to the present invention.
4 is a diagram showing a valid data signal corresponding to digital data;
5 is a view showing an example of a validation signal and an effective data signal according to the present invention;
FIG. 6 is a block diagram showing a configuration of an information delivery system using a sound wave signal according to a second embodiment of the present invention; FIG.
7 is a diagram showing an effective data signal according to a second embodiment of the present invention.

Hereinafter, embodiments of the present invention in which the above object can be specifically realized will be described with reference to the accompanying drawings. In the description of the embodiments, the same names and symbols are used for the same components, and further description thereof will be omitted.

The information transfer system using the sound wave signal according to the present invention converts digital data into sound wave signals, transmits the sound wave signals, and receives the sound wave signals to restore digital data from sound wave signals.

To this end, the information delivery system 10 using the sound wave signal according to the present invention includes a sound wave signal generator 100 and a reception terminal 200.

The sound wave signal generator 100 is for generating a sound wave signal and transmitting the sound wave signal to the receiving terminal 200. The sound wave signal generator 110 includes a sound wave signal generating unit 110 and a first speaker 120.

The sound wave signal generating unit 110 converts the digital data into a sound wave signal.

In this case, the digital data may be a character-encoded signal such as an ASCII code or a control signal for operating a specific function of the receiving terminal 200.

And the sound wave signal converts the high signal and the low signal of the digital data into an analog signal including the output and the disconnection of the sound wave, respectively. The sound wave signal includes a verification signal for distinguishing the external noise and the sound wave signal. In the present specification, a sound wave converted from substantial digital data is defined as an effective data signal, and a sound wave for distinguishing it from external noise is defined as a verification signal.

The sound wave signal generating unit 110 generates a sound wave signal including the valid data signal and the verify signal using the frequency of the bandwidth out of the audible frequency range. For example, the sound wave signal generation unit 110 generates sound wave signals in a frequency band ranging from 17 KHz to 25 KHz. In fact, even if there are people who are able to recognize the frequencies in the 17 KHz range, the number of people who can recognize such treble is very small. In addition, Therefore, it will be said that this frequency setting is not possible.

And the valid data signal and the verify signal are set to have different frequencies, respectively. For example, the sound wave signal generating unit 110 may generate a verification signal using a frequency of 20 KHz, and may generate a valid data signal using a frequency of 22 KHz.

The first speaker 120 is for transmitting a sound wave signal to the receiving terminal 200. That is, any of the first speaker 120 according to the present invention may be used as long as it can output a frequency of 17 KHz to 25 KHz, which is a frequency range of a sound wave signal.

The receiving terminal 200 receives a sound wave signal transmitted from the sound wave signal generator 100, converts the valid data signal into digital data, and performs a specific operation.

The receiving terminal 200 includes a microphone 210, first and second filter units 211 and 212, first and second digital converters 221 and 222, a memory 250 and a control unit 225.

The microphone 210 receives the sound wave signal transmitted from the sound wave signal generator 100 and uses the sound wave signal capable of receiving a frequency of 17 KHz to 25 KHz.

The first filter unit 211 filters the first sound wave having the same frequency as the verification signal among the sound waves received by the microphone 210 and transmits the first sound wave to the first data conversion unit 221. Similarly, the second filter unit 212 filters the second sound wave having the same frequency as the effective data signal among the sound waves received by the microphone 210, and transmits the filtered second sound wave to the second data converter 222.

The first and second digital converters 221 and 222 convert the first and second sound waves received from the first and second filter units 211 and 212 into first and second digital signals, respectively. That is, the first digital converter 221 converts the first sound wave of 20 KHz, which is the frequency of the verification signal, into the first digital signal, and transmits the first digital signal to the controller 225. Similarly, the second digital converter 222 converts the second sound wave of 22 KHz, which is the frequency of the effective data signal, to the second digital signal, and transmits the second digital signal to the controller 225.

The memory 250 stores a verification signal pattern and a valid data signal pattern which are patterns of a verification signal and an effective data signal generated by the sound wave signal generator 100. At this time, the verification signal pattern is for verifying that the first digital signal output from the first digital converter 221 is a digital signal of the verification signal. Similarly, the valid data signal pattern is for confirming whether the second digital signal output from the second digital converter 222 is an effective data signal, and is pattern information for the start signal and the end signal.

The control unit 225 confirms the sound signal based on the first and second digital signals supplied from the first and second digital conversion units 221 and 222 and processes the data signal included in the effective data signal of the sound signal.

That is, when the digital signal provided from the first digital conversion unit 221 is the same as the pattern of the verification signal stored in the memory 250, The digital signal is regarded as a digital signal for the valid data signal transmitted from the sound wave signal generator 100, and signal processing according to the digital data is performed.

For example, in accordance with the setting condition, when the digital data is ASCII code, the control unit 225 displays the character corresponding to the ASCII code on the display 231. [ Alternatively, when the digital data is a control signal, the control unit 225 executes an operation corresponding to the control signal. The signal processing of the digital data of the control unit 225 may be varied according to the type of the digital data and the setting of the receiving terminal 200.

A method for transmitting information using the information transmission system using the sound wave signal according to the present invention will now be described with reference to the flowchart of FIG.

<Effective data signal generation: S301>

For the implementation of the present invention, the sound wave signal generator 110 of the sound wave signal generator 100 generates a valid data signal corresponding to the digital data.

4 is a diagram showing an example of digital data and a corresponding valid data signal. The digital data shown in Fig. 4 outputs a high signal in the period of t0, t1, t3 and t5, and outputs a low signal in the period of t2 and t4.

The sound wave signal generating unit 110 converts the digital data into an effective data signal in which the output of the sound wave and the disconnection are repeated. At this time, the sound wave signal generating unit 110 generates a valid data signal that outputs or does not output the sound wave corresponding to the high signal and the low signal of the digital data. For example, the sound wave signal generator 110 outputs sound waves during the periods t0, t1, t3, and t5, and generates valid data signals that do not output sound waves during the periods t2 and t4.

And the valid data signal may include a 'start signal' and a 'end signal' as shown in FIG. The start signal and the end signal are signals for distinguishing the start and end of the actual 'data signal' of the valid data signal, respectively.

In particular, the start signal and the end signal of the valid data signal are generated as a secondary reference for distinguishing the sound wave signal from the external noise, and correspond to a predetermined effective data signal pattern as shown in FIG. Secondary confirmation of the sound wave signal using the effective data signal pattern will be described in detail through a process of detecting a sound wave signal in a receiving terminal described later.

&Lt; Verification signal generation: S303 >

The sound wave signal generation unit 110 also generates a verification signal. The verification signal is for distinguishing the valid data signal from other external noise, and may be generated using a frequency band different from that of the valid data signal.

The sound signal generator 110 generates a verification signal having the same pattern as that stored in the memory 250 of the receiving terminal 200. The verification signal may also include a 'start signal' and a 'termination signal'. The start signal and the end signal are signals for distinguishing the start and end of the verify signal, respectively.

At this time, the start signal and the end signal of the verify signal are set to have the same interval as the start signal and the end signal interval of the valid data signal, as shown in FIG. That is, the start signal and the end signal of the verification signal are signals for which the receiving terminal 200 serves as a reference for distinguishing the start signal and the end signal of the valid data signal.

The verification signal is set to correspond to the verification signal pattern stored in the receiving terminal 200, as shown in FIG. 5, as a primary reference for identifying the sound signal from the external noise.

&Lt; Sound wave signal generation and transmission: S305, S307 >

The sound signal generator 110 synthesizes an effective data signal and a verification signal as shown in FIG. 5 to generate a sound signal, and transmits the generated sound signal to the receiving terminal 200.

The sound wave signal generator 100 transmits a sound wave signal through the speaker 120, and the time when the sound wave signal is transmitted may vary according to the embodiment of the present invention. For example, the sound wave signal generator 100 may continuously transmit a sound wave signal to an unspecified user, or may transmit a sound wave signal only under specific conditions.

<Acoustic signal reception and verification signal detection: S309, S311>

The receiving terminal 200 continuously receives a sound wave including a sound wave signal and noise from the microphone 210. The receiving terminal 200 distinguishes the sound signal from the external noise based on whether or not the verification signal is detected.

This process is as follows.

The first filter unit 211 filters the first sound wave having the same frequency as the verification signal from the sound wave received by the microphone 210, and provides the first sound wave to the first digital conversion unit 221. The first digital converter 221 converts the received first sound wave into a first digital signal and provides the first digital signal to the controller 225.

At the same time that the sound wave passing through the first filter unit 211 is digitally converted and processed by the control unit 225, the second filter unit 212 converts the sound wave received by the microphone 210 to the same frequency as the effective data signal And supplies the filtered second sound wave to the second digital converter 222. [ The second digital converter 222 converts the received second sound wave into a second digital signal and provides the second digital signal to the controller 225.

The control unit 225 compares the first digital signal with the verification signal pattern stored in the memory 250 and determines the first sound wave as a verification signal when the first digital signal matches the verification signal pattern.

<Confirmation of sound wave signal: S313>

The control unit 225, which detects the verification signal, confirms whether there is a sound wave signal received simultaneously with the verification signal.

The control unit 225 compares the start signal of the second digital signal corresponding to the start signal section of the first digital signal with the valid data signal pattern stored in the memory 250 when determining that the first sound wave is the verify signal. When the start signal of the second digital signal is the same as the valid data signal pattern, the second sound wave is determined to be an effective data signal.

In other words, the control unit 225 primarily determines whether the first sound wave of 20 KHz passing through the first filter unit 211 is a verification signal by grasping the first digital signal pattern.

The control unit 225 determines whether the second sound wave of 22 kHz passing through the second filter unit 212 is an effective data signal by detecting whether the start signal of the second digital signal is a start signal of the valid data signal, .

In this way, the control unit 225 determines whether the sound wave received by the microphone 210 is a sound wave signal by confirming the start signal of the validation signal and the valid data signal.

At this time, in a state where the control unit 225 does not detect the verification signal, the sound wave received by the microphone 210 is regarded as noise, and the sound wave is continuously received.

<Digital data acquisition: S315>

The control unit 225 which confirms the sound wave signal using the verification signal and the valid data signal acquires the data signal between the start signal and the end signal of the valid data signal as initial digital data.

<Digital Data Instruction Processing: S317>

Based on the data signal of the valid data signal, the control unit 225 performs signal processing of the digital data before being transformed into the sound wave signal by the sound wave signal generator 100.

For example, when the digital data is a character such as an ASCII code, the control unit 225 displays the character corresponding to the digital data through the display 231

Alternatively, when the digital data is a control signal for controlling the specific operation of the receiving terminal 200, the control unit 225 operates a function indicated by the corresponding control signal. At this time, the control signal may be a sound source or an image stored in the receiving terminal 200 through the second speaker 232 or the display 231, or may connect the receiving terminal 200 to a specific web page.

6 is a block diagram illustrating a configuration of an information delivery system using a sound wave signal according to a second embodiment of the present invention. The information delivery system using the sound wave signal according to the second embodiment separates digital data into two valid data signals and transmits and receives the data. In the second embodiment, the same reference numerals are used for the same or very similar components as those in the above embodiment, and a detailed description thereof will be omitted.

To this end, the sound wave signal generator 111 of the sound wave signal generator 100 separates and converts the digital data into first and second valid data signals as shown in FIG.

The first and second valid data signals are obtained by converting the first half period T1 and the second half period T2 of the digital data into the sound wave signals. That is, the sound wave signal generation unit 111 divides the digital data interval into two, and converts each interval into the sound wave signal.

At this time, the sound wave signal generating unit 111 generates the first and second effective data signals using sound waves having different frequencies.

The receiving terminal 200 includes a first filter unit 211 for detecting a verification signal and second and third filter units 212 and 213 for detecting two valid data signals.

The second and third sound waves separated through the second and third filter units 212 and 213 are converted into second and third digital signals via the second and third digital conversion units 222 and 223, respectively. The second and third digital signals are provided to the control unit 226.

The control unit 226 confirms whether the second and third digital signals are valid data signals when the signal passing through the first filter unit 211 is a verification signal. That is, when the start signals of the second and third digital signals are the same as the start signal patterns of the preset valid data signals, the control unit 226 outputs the second and third sound waves as the first and second effective data signals, respectively .

The control unit 226 connects the second and third digital signals and processes the second and third digital signals connected thereto as one digital data.

This second embodiment may be extended to other embodiments based on the number of separating valid data signals. For example, the sound wave signal generator 100 separates digital data into three or more valid data signals and transmits them, and the receiving terminal 200 can perform signal processing of the first digital data by connecting respective valid data signals.

Hereinafter, an application example of the information transmission using the sound wave signal according to the present invention will be described.

* Example 1 - Acquisition of location information

The sound wave signal generator 100 is installed in an area where it is difficult to receive GPS signals and can provide GPS coordinates to the user who owns the receiving terminal 200 without receiving GPS coordinates from the satellites.

That is, the sound wave signal generator 100 converts digital data of GPS coordinates of the position where the sound wave signal generator 100 is installed into sound wave signals, and transmits the sound wave signals. The receiving terminal 200 may receive the sound signal transmitted by the sound signal generator 100 to acquire GPS coordinates.

The receiving terminal 200 may provide other services based on the location information to the user using the GPS coordinates.

* Example 2 - Providing information on products

The sound wave signal generator 100 can provide information on a product or an article to a user having the receiving terminal 200 by transmitting information on a goods or an object using a sound wave signal.

At this time, the sound wave signal may be an ASCII code for displaying direct product information, or the sound wave signal may be a control signal for extracting the information when the receiving terminal 200 stores information on a specific store.

* Third application example - Guidance information of the place

The sound signal generator according to the present invention can be installed in a train history, a bus stop, or a building to provide information on the installation site.

For example, the sound wave generator 100 installed in the train history can inform the signaling system of the traffic lights at the crosswalk where the traffic lights are installed. For this purpose, the sound signal generator 100 distinguishes and transmits digital data according to a signal of a signal, and the receiving terminal 200 extracts audio information corresponding to the digital data from the memory 250 and outputs the extracted audio information through the second speaker .

Since the method of notifying the traffic lights using this method does not use the audio frequency, it is possible to broadcast the guidance to the visually impaired while reducing the noise of the distance.

It is to be understood by those skilled in the art that the present invention may be embodied in many other forms without departing from the spirit and scope of the invention, Accordingly, the above-described embodiments are to be considered illustrative and not restrictive, and all embodiments falling within the scope of the appended claims and their equivalents are intended to be included within the scope of the present invention.

100: sound wave signal generator 110: sound wave signal generator
120: speaker 200: receiving terminal
210: microphone (microphone) 230: second speaker
231: Display 232: Speaker

Claims (11)

The sound wave signal generator converts the digital data into a sound wave signal in a frequency band of 17 KHz to 25 KHz and the sound wave signal generator includes an effective data signal that outputs or does not output a sound wave corresponding to the high signal period and the low signal period in the digital data Generating the sound wave signal;
The receiving terminal receiving the sound wave signal;
The receiving terminal reconstructing the sound wave signal into the digital data; And
The receiving terminal performing signal processing of the digital data,
Generating the sound wave signal includes: generating the valid data signal including a start signal and an end signal preset in advance and stored in the receiving terminal; Generating a verification signal that is preset to distinguish the valid data signal from external noise and stores a pattern in the receiving terminal; And synthesizing the valid data signal and the verify signal,
The generating of the valid data signal includes generating the effective data signal such that the sound wave corresponding to the high signal period of the digital data is output and the sound wave is not output corresponding to the low signal period of the digital data A method for transmitting information using a sound signal.
delete delete The method according to claim 1,
The step of restoring the sound wave signal into the digital data
Filtering the sound waves received by the microphone of the receiving terminal with sound waves having the same frequency as the validation signal and the valid data signal and separating them into first and second sound waves, respectively;
Converting each of the first and second sound waves to generate first and second digital signals;
Determining a first sound wave as a verification signal when the first digital signal is the same as a preset verification signal pattern;
Determining a second sound wave as an effective data signal when the start signal of the second digital signal corresponding to the start signal section of the first digital signal is the same as the start signal pattern of the preset effective data signal; And
And extracting digital data between the start signal and the end signal in the second digital signal to perform signal processing of the digital data.
The method according to claim 1,
The step of generating the valid data signal
Dividing a period of the digital data into two halves to divide the data into a first half section and a second half section, and converting the first half section and the second half section into first and second valid data signals, respectively.
6. The method of claim 5,
The step of restoring the sound wave signal into the digital data
Filtering the sound waves received by the microphone of the receiving terminal with sound waves having the same frequency as the verification signal, the first and second valid data signals, and separating the sound waves into first to third sound waves;
Converting each of the first to third sound waves to generate first and second digital signals;
Determining a first sound wave as a verification signal when the first digital signal is the same as a preset verification signal pattern;
When the start signal of the second and third digital signals corresponding to the start signal period of the first digital signal is the same as the start signal pattern of the preset valid data signal, 2) judging a valid data signal; And
And connecting the second and third digital signals to each other to process the connected second and third digital signals as one digital data.
The method according to any one of claims 1, 4, 5, and 6,
Wherein the step of generating the sound wave signal converts the digital data, which is an ASCII code, into an effective data signal.
The digital data is converted into a sound wave signal in the frequency band of 17 KHz to 25 KHz and is transmitted to the outside. The sound wave signal includes an effective data signal which does not output or output a sound wave corresponding to a high signal interval and a low signal interval of the binary signal of the digital data, A sound wave signal generator; And
And a receiving terminal for receiving the sound wave signal transmitted from the sound wave signal generator and restoring the digital data to perform signal processing of the digital data,
The effective data signal does not output a sound wave corresponding to a section in which the digital data outputs a low signal and a sound wave corresponding to a section in which the digital data outputs a low signal,
Wherein the valid data signal includes a start signal and an end signal that are preset and stored in the receiving terminal,
Wherein the sound wave signal generator generates the sound wave signal by generating a verification signal in which a pattern is stored in the receiving terminal in advance to distinguish the valid data signal from external noise and combining the validation signal with the valid data signal, Information delivery system used.
delete delete 9. The method of claim 8,
The receiving terminal
A memory for storing the valid data signal pattern and the verification signal pattern;
A microphone for receiving the sound waves;
A first filter unit for filtering a sound wave having the same frequency as the verification signal in the sound wave to separate the first sound wave;
A second filter unit for filtering a sound wave having the same frequency as the valid data signal from the sound wave to separate the second sound wave;
First and second digital conversion units for converting the first and second sound waves output from the first and second filter units respectively to generate first and second digital signals; And
A start signal of the valid data signal in a section corresponding to the start signal of the verify signal is checked if the first digital signal output from the first digital converter is the same as the verify signal pattern stored in the memory And a control unit for processing the data signal between the start signal and the end signal of the valid data signal as digital data.

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