JP2009296551A - Communication system, voice-generating method, receiving device, and transmitting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a communication system, a voice-generating method, a receiving device, and a transmitting device. <P>SOLUTION: The communication system includes the transmission device, having a voice generation unit which generates a voice signal and a transmission electrode, electrostatically coupled to a communication medium and transmitting the voice signal via the communication medium, and the receiving device having a receiving electrode electrostatically coupled to the communication medium and receiving the voice signal transmitted from the transmission device via the communication medium, and a voice-generating unit converting the voice signal, received by the reception electrode into air vibrations using a power component contained in the voice signal. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a communication system, a sound generation method, a reception device, and a transmission device.

  Recently, research on electrostatic field communication using a human body or space as a communication medium has been widely performed. For example, electrostatic field communication is performed between two communication devices including a reference electrode and a signal electrode. More specifically, the signal electrode of both communication devices and the human body are electrostatically coupled, and the reference electrode and space of both communication devices are electrostatically coupled to form a closed circuit. The communication device on the transmission side transmits a signal by generating a potential difference between the signal electrode and the reference electrode, and receives the signal by detecting the potential difference between the signal electrode and the reference electrode of the communication device on the reception side. Such electrostatic field communication is described, for example, in Patent Document 1 below.

  Conventionally, the user can listen to the sound converted from the sound signal to the air vibration in the headphones by wearing the headphones. Here, a form in which the audio signal is transmitted by wire from the audio signal generation apparatus and a form in which the audio signal is transmitted wirelessly (including infrared rays) are proposed.

JP 2006-324775 A

  However, in the form in which the audio signal is transmitted by wire, there is a case where the wearing of the headphones becomes complicated because the wire portion needs to be routed or the wire portion is entangled. Moreover, in the form which transmits an audio | voice signal by radio | wireless, it was necessary to provide a battery with a receiving circuit and an electric power supply source required for audio | voice signal generation | occurrence | production, for example, and there existed a problem that handling was complicated.

  Therefore, the present invention has been made in view of the above problems, and an object of the present invention is to provide a new and improved communication system and sound generation capable of reproducing a sound signal more easily. It is to provide a method, a receiving device, and a transmitting device.

In order to solve the above problems, according to an aspect of the present invention, a sound generation unit that generates a sound signal, a transmission electrode that is electrostatically coupled to a communication medium and transmits the sound signal via the communication medium,
A receiving device that is electrostatically coupled to the communication medium and receives the audio signal transmitted from the transmitting device via the communication medium, and the audio signal received by the receiving electrode. There is provided a communication system including a reception device having a sound generation unit that reproduces using a power component included in the sound signal.

  The receiver further includes a power generation unit that smoothes the audio signal to generate DC power, and the audio generation unit uses the DC power generated by the power generation unit to generate the audio signal. The signal may be reproduced.

  The voice generation unit may include an amplification unit that amplifies the voice signal using DC power generated by the power generation unit.

  The receiving device further includes a power generation unit having a photoelectric conversion function or a thermoelectric conversion function, and the sound generation unit reproduces the sound signal by further using the power generated by the power generation unit. May be.

  At least one of the transmission device and the reception device may further include an impedance matching unit that performs impedance matching so as to be in a resonance state at the transmission frequency of the audio signal.

  The communication medium may be a human body, the sound generation unit may be disposed near the ears of the human body, and the reception electrode may be disposed on the head between both ears of the human body.

  In order to solve the above-described problem, according to another aspect of the present invention, a step of generating an audio signal and a transmission electrode electrostatically coupled to the communication medium transmit the audio signal via the communication medium. A receiving electrode electrostatically coupled with the communication medium, receiving the audio signal transmitted from the transmitting electrode via the communication medium, and receiving the audio signal received by the receiving electrode. And reproducing using a power component included in the audio signal.

  In order to solve the above-described problem, according to another aspect of the present invention, a receiving electrode that is electrostatically coupled to a communication medium and receives an audio signal transmitted via the communication medium, and the receiving electrode There is provided a reception device including an audio generation unit that reproduces the received audio signal using a power component included in the audio signal.

  In order to solve the above problem, according to another aspect of the present invention, an audio generation unit that generates an audio signal and a communication medium are electrostatically coupled, and the audio signal is transmitted via the communication medium. A transmission device is provided that includes a transmission electrode and an impedance matching unit that performs impedance matching so as to be in a resonance state at a transmission frequency of the audio signal.

  As described above, according to the communication system, the sound generation method, the reception device, and the transmission device according to the present invention, the sound signal can be reproduced more simply.

  Exemplary embodiments of the present invention will be described below in detail with reference to the accompanying drawings. In addition, in this specification and drawing, about the component which has the substantially same function structure, duplication description is abbreviate | omitted by attaching | subjecting the same code | symbol.

Further, the “best mode for carrying out the invention” will be described according to the following item order.
[1] Background to the present embodiment [2] Overall configuration of the communication system according to the present embodiment [3] First embodiment [3-1] Configuration of the transmission apparatus according to the first embodiment [3-2 ] Configuration of the receiving apparatus according to the first embodiment [3-3] About impedance matching [4] Second embodiment [4-1] Configuration of the receiving apparatus according to the second embodiment [4-2] No. Operation of the receiving apparatus according to the second embodiment [5] Third embodiment [6] Summary

[1] Background to the Present Embodiment First, the background to the present embodiment will be described with reference to FIG. 13 and FIG. 14 and a speech processing system related to the present embodiment as a comparative example.

  FIG. 13 is an explanatory diagram showing the configuration of the first sound processing system related to the present embodiment. As shown in FIG. 13, the first audio processing system includes headphones 32, an audio signal generation device 34, and a wired portion 36. The headphone 32 is attached to the head of the human body 20, converts the audio signal generated by the audio signal generation device 34 and transmitted via the wired portion 36 into air vibration and outputs the air vibration.

  FIG. 14 is an explanatory diagram showing a configuration of a second sound processing system related to the present embodiment. As shown in FIG. 14, the second sound processing system includes headphones 40 and a wireless transmission device 42. The wireless transmission device 42 includes an audio signal generation circuit and a transmission circuit for transmitting the generated audio signal by a radio signal or infrared rays. The headphones 40 include a reception circuit that receives a radio signal or an audio signal transmitted by infrared rays from the radio transmission device 42, and an audio generation circuit that converts the audio signal received by the reception circuit into air vibration and outputs the air vibration.

  However, in the first audio processing system related to the present embodiment, when the headphones 32 are worn, the wired portion 36 needs to be routed or the tangled wired portion 36 needs to be unwound, and the user is troublesome. Was expensive. Further, in the second sound processing system related to the present embodiment, it is necessary to provide the headphones 40 with a battery for supplying power to the reception circuit and the sound generation circuit of the headphones 40, and there is a problem that handling is complicated. .

  Then, it came to create the 1st-3rd embodiment of this invention focusing on the said situation. According to the first to third embodiments of the present invention, the audio signal can be reproduced with ease of handling by the user. Hereinafter, after describing the overall configuration of the present embodiment, each of the first to third embodiments of the present invention will be described in detail.

[2] Overall Configuration of Communication System According to this Embodiment FIG. 1 is an explanatory diagram showing the overall configuration of the communication system 1 according to this embodiment. As shown in FIG. 1, the communication system 1 according to the present embodiment includes a transmission device 10 having a transmission electrode 110, a reception device 12 having a reception electrode 160, and a human body 20.

  The transmission electrode 110 of the transmission device 10 is an electrode for forming electrostatic coupling with the human body 20 that is a communication medium. The transmission device 10 can transmit a signal from the transmission electrode 110 by an electric field. In the present specification, audio signals such as music, lectures, and radio programs are described as examples of signals transmitted from the transmission apparatus 10, but the present invention is not limited to such examples. For example, the signal transmitted from the transmission device 10 may be a video signal such as a movie, a television program, a video program, a photograph, a document, a picture, and a chart, or an arbitrary signal such as a game and software.

  The human body 20 is an example of a communication medium having dielectricity or conductivity that can transmit an electrical signal. In this specification, the human body 20 will be described as an example of the communication medium, but the communication medium is not limited to the human body 20. For example, as communication media, metals that are conductors such as aluminum, copper, iron, and alloys, dielectrics such as plastic, ceramic, rubber, and glass, and plants that have properties as both these conductors and dielectrics. And any object such as a living body including an animal.

  The receiving electrode 160 of the receiving device 12 is an electrode for forming electrostatic coupling with the human body 20 that is a communication medium. The receiving device 12 can receive a signal transmitted from the transmitting device 10 by an electric field through the receiving electrode 160.

[3] First Embodiment [3-1] Configuration of Transmitting Device According to First Embodiment The overall configuration of the communication system 1 according to the present embodiment has been described above with reference to FIG. Next, the configuration of the transmission apparatus 10 according to the first embodiment of the present invention will be described with reference to FIG.

  FIG. 2 is a functional block diagram showing the configuration of the transmission apparatus 10 according to the first embodiment of the present invention. As illustrated in FIG. 2, the transmission device 10 according to the first embodiment includes a power supply source 114, a sound generation unit 118, a modulation unit 120 including a carrier wave generation unit 124 and a multiplication unit 128, and a transmission matching unit. 130 and the transmission electrode 110.

  The power supply source 114 is a power supply source for operating each component of the transmission device 10 such as the sound generation unit 118 and the modulation unit 120. The power supply source 114 may be a connection portion with an indoor wiring that acquires power from the indoor wiring, or may be an arbitrary battery such as a primary battery, a secondary battery, a fuel cell, a photovoltaic cell, and a thermal battery.

  The sound generation unit 118 generates an electric sound signal based on the power supplied from the power supply source 114. For example, the audio generation unit 118 may convert analog or digital audio data stored in the storage medium into an audio signal. Storage media include non-volatile memories such as EEPROM (Electrically Erasable Programmable Read-Only Memory) and EPROM (Erasable Programmable Read Only Memory), CDs such as hard disks and disk-type magnetic disks, etc. (Recordable) / RW (ReWriteable), DVD-R (Digital Versatile Disc Recordable) / RW / + R / + RW / RAM (Random Access Memory) and BD (Blu-Ray Disc-R) Optical discs and MO (Magneto Optical ) Disc etc.

  Moreover, the audio | voice production | generation part 118 may produce | generate an audio | voice signal based on the signal acquired from the outside, such as AM broadcast and FM broadcast. In addition, the audio generation unit 118 may generate an electric audio signal by an arbitrary method, and many commercially available dedicated ICs may be applied as the audio generation unit 118.

  The carrier wave generation unit 124 generates a sine wave of, for example, several M to several hundreds of MHz, which is a sufficiently high frequency for the audio signal, as a carrier wave. The multiplier 128 multiplies the audio signal generated by the audio generator 118 by the carrier wave generated by the carrier wave generator 124, thereby amplitude-modulating the audio signal.

  In the present specification, an explanation will be given with an emphasis on an example in which the modulation method of the audio signal is an amplitude modulation method, but the present invention is not limited to such an example. For example, the audio signal modulation method may be a frequency modulation method or a phase modulation method. Also, the modulation unit 120 is realized by a configuration according to the modulation method of the audio signal.

  The transmission matching unit 130 has a function as an impedance matching unit that performs frequency band limitation and impedance matching on the modulated audio signal modulated by the modulation unit 120 as necessary. The matching process by the transmission matching unit 130 will be described later in “[3-3] Impedance matching”.

  The transmission electrode 110 transmits the modulated audio signal output from the transmission matching unit 130 into the human body 20 through electrostatic coupling formed with the human body 20.

[3-2] Configuration of Receiving Device According to First Embodiment Next, the configuration of the receiving device 12 according to the first embodiment will be described with reference to FIGS.

  FIG. 3 is an explanatory diagram schematically illustrating an external configuration of the receiving device 12 according to the first embodiment. As illustrated in FIG. 3, the receiving device 12 according to the first embodiment includes a receiving electrode 160, a reference electrode 162, a circuit unit 172, and a speaker 188, and is attached to the head of the human body 20. As shown in FIG. 3, the receiving electrode 160 is arranged at a position corresponding to the head between both ears in addition to the vicinity of the ear of the human body 20, so that the electric field transmitted from the transmitting device 10 can be efficiently transmitted. Can be detected and received. The reference electrode 162 is a conductor for forming a capacitance between the reference electrode 162 and the space.

  FIG. 4 is a functional block diagram showing an internal configuration of the receiving device 12 according to the first embodiment. As shown in FIG. 4, the receiving device 12 according to the first embodiment includes a receiving electrode 160, a receiving matching unit 164, a demodulating unit 170 including a detecting unit 174 and an LPF 178, an impedance matching unit 184, and a speaker 188. A voice generation unit 180 including

  The reception electrode 160 receives the modulated audio signal transmitted from the transmission device 10 by the electric field via the human body 20. The reception matching unit 164 has a function as an impedance matching unit that performs frequency band limitation and impedance matching on the modulated audio signal received by the reception electrode 160 as necessary. The matching processing by the reception matching unit 164 will be described later in “[3-3] Impedance matching”.

  The detector 174 detects the modulated audio signal input from the reception matching unit 164, and the LPF (low-pass filter) 178 extracts the audio signal from the detected modulated audio signal and outputs it to the audio generator 180. Hereinafter, the manner in which the sound signal is extracted by the detection unit 174 and the LPF 178 will be specifically described with reference to FIG.

  FIG. 5 is an explanatory diagram showing a state in which a sound signal is extracted by the detection unit 174 and the LPF 178. The left diagram of FIG. 5 shows a modulated audio signal input from the reception matching unit 164 to the detector 174, and the modulated audio signal shown in the center diagram of FIG. 5 is detected by the detector 174 detecting the modulated audio signal. Is obtained. Further, the LPF 178 selectively passes the low-frequency component of the modulated audio signal shown in the center diagram of FIG. 5, so that the audio signal shown in the right diagram of FIG. 5 is obtained.

  The impedance matching unit 184 performs impedance matching with the subsequent speaker 188. The speaker 188 converts the audio signal input from the impedance matching unit 184 into air vibration and outputs the air vibration. Here, the speaker 188 is driven using, for example, the audio signal shown in the right diagram of FIG. 5 as a power source. That is, the speaker 188 operates based on the power component included in the audio signal. Therefore, according to the present embodiment, it is possible to output sound in the receiving device 12 without providing a power source in the receiving device 12 and without connecting the receiving device 12 and the transmitting device 10 by wire. . For this reason, according to this embodiment, handling of the receiver 12 by a user can be simplified more.

  Note that the reception matching unit 164, the demodulation unit 170, the impedance matching unit 184, and the like illustrated in FIG. 4 correspond to the circuit unit 172 illustrated in FIG. In the above description, an example in which the speaker 188 converts an audio signal into air vibration has been described as an example of reproduction. However, the present invention is not limited to this example. For example, the receiving device 12 may output an audio signal as bone vibration.

[3-3] Impedance Matching Next, functions of the transmission matching unit 130 and the reception matching unit 164 will be described with reference to FIGS.

  The resistance value of the epidermis (skin) of the human body 20 is about several tens of kΩ per square centimeter, but the resistance value of the lower tissue of the epidermis is low, about several kΩ. Further, the capacitance formed between the transmission electrode 110 and the human body 20 can be considered equivalent to the capacitance formed between the electrode facing the transmission electrode 110 and the transmission electrode 110 (for example, a special feature). Open 2006-324775). Therefore, an equivalent circuit of the communication system 1 including the transmission device 10 and the reception device 12 can be considered as shown in FIG.

  FIG. 6 is an explanatory diagram showing an equivalent circuit of the communication system 1 including the transmission device 10 and the reception device 12. In FIG. 6, a capacitor Ct1 is a capacitance formed between the transmission electrode 110 and the human body 20, a capacitor Cr1 is a capacitance formed between the reception electrode 160 and the human body 20, and the resistance Rh is This is the resistance value of the human body 20. Further, the capacitor Ct2 indicates the electrostatic capacity with respect to the space of the transmission device 10, and the ground is virtual. Similarly, the capacitor Cr2 indicates a capacitance with respect to the space of the receiving device 12, and the ground is virtual. The capacitors Ct1, Ct2, Cr1, and Cr2 have an electrostatic capacity of about several pF to several tens [pF], for example, depending on the size of the electrode and the device.

  Here, the transmission matching unit 130 and the reception matching unit 164 have inductance components, the inductance of the transmission matching unit 130 is Lt1, and the inductance of the reception matching unit 164 is Lr1. Further, assuming that the output from the modulation unit 120 is V and the impedance of the demodulation unit 170 is Rr, the equivalent circuit of the communication system 1 can be further considered as shown in FIG.

  FIG. 7 is an explanatory diagram showing another equivalent circuit of the communication system 1 including the transmission device 10 and the reception device 12. In FIG. 7, a combined inductor La indicates an inductance component obtained by virtually connecting inductors Lt1 and Lr1 in series. The combined capacitance Ca represents a capacitor component obtained when the capacitors Ct1, Ct2, Cr1, and Cr2 are virtually all connected in series.

  As illustrated in FIG. 7, the communication system 1 including the transmission device 10 and the reception device 12 can be regarded as a series resonance circuit in which the entire system includes an inductor and a capacitor. Here, assuming that R = Rh + Rr, the impedance of the entire circuit can be obtained by the following formula 1.

（数式１）
数式１において、ωは搬送波発生部１２４により発生される搬送波の角周波数である。また、インピーダンスＺの大きさは、以下の数式２により求めることができる。

(Formula 1)
In Equation 1, ω is the angular frequency of the carrier wave generated by the carrier wave generator 124. Further, the magnitude of the impedance Z can be obtained by the following formula 2.

（数式２）
さらに、数式１において｜Ｚ｜が最小となるωは、以下の数式３により表現される。

(Formula 2)
Further, ω that minimizes | Z | in Equation 1 is expressed by Equation 3 below.

（数式３）
｜Ｚ｜が上記数式３を満たす場合、Ｚ＝Ｒとなり、回路に流れる電流｜Ｉ｜が最大（｜Ｉ｜ｍａｘ）となる。この｜Ｉ｜ｍａｘは、以下の数式４のように表現される。

(Formula 3)
When | Z | satisfies the above Equation 3, Z = R, and the current | I | flowing through the circuit is maximum (| I | max). This | I | max is expressed as Equation 4 below.

（数式４）
ここで、角周波数ωに着目すると、回路に流れる電流｜Ｉ（ω）｜は、図８に示す特性を有する。

(Formula 4)
Here, focusing on the angular frequency ω, the current | I (ω) | flowing through the circuit has the characteristics shown in FIG.

  FIG. 8 is an explanatory diagram showing the relationship between the current flowing through the circuit and the angular frequency. In FIG. 8, ωr indicates an angular frequency at which | I (ω) | becomes maximum, and the circuit is in a resonance state when the angular frequency is ωr. If the voltage across the combined inductor La is VL and the voltage across the combined capacitance Ca is VC, the following equation 5 is established in the resonance state of the circuit, which is equivalent to the circuit having the pure resistance R.

ＶＬ＝−ＶＣ （数式５）
したがって、共振回路の共振の強さをＱは、以下の数式６のように表現される。

VL = −VC (Formula 5)
Accordingly, the resonance intensity Q of the resonance circuit is expressed as the following Equation 6.

（数式６）

(Formula 6)

  Accordingly, one or both of the transmission matching unit 130 and the reception matching unit 164 dynamically controls the combined inductor La so that each frequency ωr in the resonance state matches the angular frequency of the carrier wave, so that the maximum power can be obtained. The signal transmission may be realized. When the transmission matching unit 130 and the reception matching unit 164 have variable capacitor components, the transmission matching unit 130 and the reception matching unit 164 further control the size of the capacitor component so that each frequency ωr in the resonance state matches the angular frequency of the carrier wave. The signal transmission with the maximum power may be realized. Further, when the impedances of the transmission matching unit 130 and the reception matching unit 164 are fixed, the transmission matching unit 130 controls the carrier wave generation unit 124 so that the angular frequency of the carrier wave matches each frequency ωr at which the resonance state occurs. May be.

  In the actual operation, it is necessary to consider various losses. However, if the receiver 12 is actually mounted on the head of the human body 20 and the transmitter 10 is held by hand, the receiver 12 is measured. A signal having a power of about several hundred μW to several mW is obtained.

  Here, along with recent technological advancement, development of audio output devices such as speakers and headphones that efficiently output audio with less power is progressing. For example, headphones having a performance of about 100 dB / mW exist, but 100 dB is a loud volume comparable to noise in a busy street or when a train passes under a guard. The supplied power when sound that can be audible with headphones having such performance is about several μW. A unit such as dB SPL or dB / mW indicating the performance of the audio output device represents a sound pressure level generated by 1 mW of power.

  Therefore, according to the receiving device 12 according to the present embodiment that can obtain power of about several hundred μW to several mW as described above, it is possible to output sound having a sound volume in a practical range.

[4] Second Embodiment As described above, according to the first embodiment of the present invention, sufficient power for converting an audio signal into air vibration can be obtained from the audio signal. However, depending on the device configuration on the receiving side, DC power may be required to convert the audio signal into air vibration. Accordingly, the second embodiment of the present invention has been invented with such circumstances taken into consideration. According to the second embodiment of the present invention, it is possible to acquire DC power and use the DC power for conversion from an audio signal to air vibration. Hereinafter, the second embodiment of the present invention will be described.

[4-1] Configuration of Receiving Device According to Second Embodiment FIG. 9 is a functional block diagram showing the configuration of the receiving device 13 according to the second embodiment of the present invention. As shown in FIG. 9, the receiving device 13 includes a receiving electrode 160, a receiving matching unit 164, a demodulating unit 170 including a detecting unit 174 and an LPF 178, an audio generating unit 181 including an amplifying unit 185 and a speaker 188. A power generation unit 190. Note that the transmission apparatus 10 according to the first embodiment can also be applied to the second embodiment of the present invention.

  The configuration of the receiving electrode 160, the receiving matching unit 164, the demodulating unit 170 including the detecting unit 174 and the LPF 178, and the speaker is substantially the same as that of the receiving device 12 according to the first embodiment. A configuration different from the embodiment will be described with emphasis.

  The power generation unit 190 generates DC power by smoothing the modulated transmission signal output from the reception matching unit 164. Then, the power generation unit 190 supplies the generated DC power to the sound generation unit 181. Note that the power generation unit 190 may supply the generated DC power to the demodulation unit 170 as necessary.

  The amplifier 185 of the sound generator 181 amplifies the sound signal extracted by the demodulator 170 using the DC power supplied from the power generator 190. Such an amplifying unit 185 may be, for example, a transistor or an amplifier IC. Further, the method of using DC power supplied from the power generation unit 190 is not limited to amplification. For example, when the audio signal modulation scheme is another analog modulation scheme such as a frequency modulation scheme or a phase modulation scheme, or various digital modulation schemes, the direct current generated by the power generation unit 190 for these demodulation processes Electric power may be used.

[4-2] Operation of Receiving Device According to Second Embodiment Next, with reference to FIG. 10, the flow of the sound generation method executed in the second embodiment will be described.

  FIG. 10 is a sequence diagram showing the flow of the sound generation method according to the second embodiment of the present invention. As shown in FIG. 10, first, the sound generation unit 118 of the transmission device 10 generates a sound signal by an arbitrary method (S204). Subsequently, the modulation unit 120 of the transmission apparatus 10 modulates the audio signal generated by the audio generation unit 118 and outputs a modulated audio signal (S208). Thereafter, the modulated audio signal is transmitted from the transmission electrode 110 of the transmission device 10 to the human body 20 (S212).

  When the modulated audio signal is received by the receiving electrode 160 of the receiving device 13, the power generation unit 190 of the receiving device 13 generates DC power by smoothing the modulated audio signal (S216).

  When the modulated audio signal is received by the receiving electrode 160 of the receiving device 13, the demodulator 170 of the receiving device 13 demodulates the modulated audio signal (S220). Then, the sound generation unit 181 of the reception device 13 uses the direct current power generated by the power generation unit 190 to convert the sound signal obtained by demodulation in the demodulation unit 170 into air vibration, and outputs it, that is, The audio signal is reproduced (S224).

  As described above, according to the second embodiment of the present invention, similarly to the first embodiment, the receiving device 13 is not provided with a power source, and the receiving device 13 and the transmitting device 10 are wired. It is possible to output sound at the receiving device 13 without connection. Furthermore, according to the second embodiment of the present invention, since the receiving device 13 can generate a DC voltage based on the modulated audio signal, the amplifying unit 185 and the like that require DC power for operation are included in the receiving device 13. Can be provided.

[5] Third Embodiment Next, a third embodiment of the present invention will be described with reference to FIGS.

  FIG. 11 is a functional block diagram showing the configuration of the receiving apparatus 14 according to the third embodiment of the present invention. As shown in FIG. 11, the receiving device 14 according to the third embodiment includes a receiving electrode 160, a receiving matching unit 164, a demodulating unit 170 including a detecting unit 174 and an LPF 178, an amplifying unit 185 and a speaker 188. An audio generation unit 181 including the photoelectric conversion unit 192; Note that the transmission apparatus 10 according to the first embodiment can also be applied to the third embodiment of the present invention.

  The configurations of the reception electrode 160, the reception matching unit 164, the demodulation unit 170 including the detection unit 174 and the LPF 178, and the sound generation unit 181 are substantially the same as those of the reception device 13 according to the second embodiment. The configuration different from the second embodiment will be described with emphasis.

  The photoelectric conversion unit 192 functions as a power generation unit that generates electric power based on natural light such as sunlight and artificial light emitted from a fluorescent lamp. The electric power generated by the photoelectric conversion unit 192 is supplied to the audio generation unit 181. The audio generation unit 181 can convert the audio signal into air vibration using the supplied electric power. Here, the arrangement position of the photoelectric conversion unit 192 will be described with reference to FIG.

  FIG. 12 is an explanatory diagram schematically illustrating an external configuration of the receiving device 14 according to the third embodiment. As shown in FIG. 12, the photoelectric conversion unit 192 is located not only in the vicinity of both ears of the human body 20 but also in the top of the head between both ears, and outside the other configuration such as the reception electrode 160. Is provided. With this configuration, since the photoelectric conversion unit 192 can receive light over a wide area, the photoelectric conversion unit 192 can generate larger electric power.

  11 and 12 merely show the photoelectric conversion unit 192 as an example of the power generation unit, and the power generation unit is not limited to such an example. For example, the power generation unit may be a thermoelectric generation element having a thermoelectric conversion function using a temperature difference between the human body temperature and the air temperature.

[6] Summary As described above, in the first to third embodiments of the present invention, since the receiving devices 12 to 14 can operate without battery power, the handling by the user can be simplified. it can.

  Also, according to the receiving device 13 according to the second embodiment, a DC voltage can be generated based on the modulated audio signal, and therefore the receiving device 13 is provided with an amplifying unit 185 that requires DC power for operation. It becomes possible.

  Furthermore, according to the receiver 14 according to the third embodiment, since the power generation element such as the photoelectric conversion unit 192 is provided, it is possible to obtain power without depending on the power of the modulated audio signal. Design flexibility increases. Moreover, the power generation unit 190 described in the second embodiment is further provided in the reception device 14 according to the third embodiment, and the reception device 14 generates power generated by the power generation element and the power generation unit 190. It is also possible to operate using the combined power.

  In addition, although preferred embodiment of this invention was described referring an accompanying drawing, it cannot be overemphasized that this invention is not limited to the example which concerns. It will be apparent to those skilled in the art that various changes and modifications can be made within the scope of the claims, and these are naturally within the technical scope of the present invention. Understood.

  For example, each step in the processing of the communication system 1 of the present specification does not necessarily have to be processed in time series in the order described as a sequence diagram or a flowchart. For example, each step in the processing of the communication system 1 may include processing executed in parallel or individually (for example, parallel processing or object processing).

It is explanatory drawing which showed the whole structure of the communication system concerning this embodiment. It is the functional block diagram which showed the structure of the transmitter concerning the 1st Embodiment of this invention. It is explanatory drawing which showed typically the external appearance structure of the receiver concerning 1st Embodiment. It is a functional block diagram showing an internal configuration of a receiving device according to the first embodiment. It is explanatory drawing which showed a mode that an audio | voice signal was extracted by a detection part and LPF. It is explanatory drawing which showed the equivalent circuit of the communication system 1 containing a transmitter and a receiver. It is explanatory drawing which showed the other equivalent circuit of the communication system 1 containing a transmitter and a receiver. It is explanatory drawing which showed the relationship between the electric current which flows into a circuit, and an angular frequency. It is the functional block diagram which showed the structure of the receiver concerning the 2nd Embodiment of this invention. It is the sequence diagram which showed the flow of the audio | voice generation method concerning 2nd Embodiment. It is the functional block diagram which showed the structure of the receiver concerning the 3rd Embodiment of this invention. It is explanatory drawing which showed typically the external appearance structure of the receiver concerning 3rd Embodiment. It is explanatory drawing which showed the structure of the 1st audio | voice processing system relevant to this embodiment. It is explanatory drawing which showed the structure of the 2nd audio | voice processing system relevant to this embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Transmission apparatus 12, 13, 14 Reception apparatus 110 Transmission electrode 118 Audio | voice production | generation part 120 Modulation part 130 Transmission matching part 164 Reception matching part 170 Demodulation part 180,181 Voice generation part 185 Amplification part 190 Power generation part 192 Photoelectric conversion part

Claims (9)

An audio generation unit for generating an audio signal; and
A transmission electrode that is electrostatically coupled to a communication medium and transmits the audio signal via the communication medium;
A transmitting device having:
A receiving electrode that is electrostatically coupled to the communication medium and receives the audio signal transmitted from the transmission device via the communication medium; and
An audio generator that reproduces the audio signal received by the receiving electrode using a power component included in the audio signal;
A receiving device having:
A communication system comprising: The receiving device further includes a power generation unit that generates the DC power by smoothing the audio signal,
The communication system according to claim 1, wherein the sound generation unit reproduces the sound signal by using the DC power generated by the power generation unit.   The communication system according to claim 2, wherein the sound generation unit includes an amplifying unit that amplifies the sound signal using DC power generated by the power generation unit. The receiver further includes a power generation unit having a photoelectric conversion function or a thermoelectric conversion function,
The communication system according to claim 1, wherein the sound generation unit reproduces the sound signal by further using the power generated by the power generation unit.   5. The communication system according to claim 1, wherein at least one of the transmission device and the reception device further includes an impedance matching unit that performs impedance matching so as to be in a resonance state at a transmission frequency of the audio signal. The communication medium is a human body;
The sound generation unit is disposed at a position corresponding to the vicinity of the human ear,
The communication system according to claim 1, wherein the reception electrode is disposed at a position corresponding to a position on a head between both ears of a human body. Generating an audio signal;
A transmitting electrode electrostatically coupled to the communication medium transmits the audio signal via the communication medium;
A receiving electrode electrostatically coupled to the communication medium receives the audio signal transmitted from the transmitting electrode via the communication medium;
Reproducing the audio signal received by the receiving electrode using a power component included in the audio signal;
A method for generating sound. A receiving electrode that is electrostatically coupled to a communication medium and receives an audio signal transmitted through the communication medium;
An audio generator that reproduces the audio signal received by the receiving electrode using a power component included in the audio signal;
A receiving device. An audio generation unit for generating an audio signal;
A transmission electrode that is electrostatically coupled to a communication medium and transmits the audio signal via the communication medium;
An impedance matching unit that performs impedance matching so as to be in a resonance state at a transmission frequency of the audio signal;
A transmission device comprising:

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