JP2008027219A - Information processing system, receiving device and method, recording medium, and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To attain a user interface which utilizes an electrostatic field to locate a human body in space. <P>SOLUTION: A user 1003 who receives a service is located above and near a transmission device 1001. The transmission device 1001 transmits a signal to the body of the user 1003. The user 1003 brings his or her hands, fingers, or the like close to or into contact with a plurality of reception signal electrodes of a receiving device 1002. The receiving device 1002 receives the signal transmitted from the transmission device 1001 through the user 1003 by the plurality of reception signal electrodes respectively to acquire data transmitted from the transmission device 1001 and measures signal intensities of reception signals and three-dimensionally specifies the position of the body of the user 1003 brought close to or into contact with the reception signal electrodes and changes of the position on the basis of the signal intensities. This invention is applicable to a communication system. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an information processing system, a receiving apparatus and method, a recording medium, and a program, and more particularly, to realize a user interface for specifying the position of a human body in space using an electrostatic field. The present invention relates to an information processing system, a receiving apparatus and method, a recording medium, and a program.

  Conventionally, as a user interface technique using an electrostatic field, for example, there are an operation button for accepting designation of an elevator stop floor, a touch pad of a personal computer, and the like.

  In addition, as an input device that accepts a three-dimensional operation, for example, there are devices using an acceleration sensor and devices using light. (For example, refer to Patent Document 1 and Patent Document 2).

JP 2005-56409 A JP 2005-148997 A

  However, the interface using the electrostatic field as described above can detect a one-dimensional or two-dimensional movement of the user (accepts a one-dimensional or two-dimensional operation by the user), but is three-dimensional. Cannot detect a typical motion (accept a three-dimensional operation), and may not accept more various operation inputs.

  In the case of the method described in Patent Document 1, a user who performs an input operation needs to carry an input device with a built-in acceleration sensor. For example, the input operation is performed in comparison with a touchpad that can be input with bare hands. There is a possibility that the device may be gripped, the input device may be set in a state where input is possible, and the input operation may be complicated. In addition, it was necessary to consider securing the power supply of the input device. Furthermore, in this case, since the user moves the input device, the durability of the input device may be reduced.

  Further, in the case of the method described in Patent Document 2, since the rotation of the trackball is detected using light, there is a risk that an error is likely to occur due to the influence of the external environment. In addition, the method of detecting the rotation of the trackball using this light requires a polygonal mirror surface that reflects the light, and it may be difficult to specify the position only by the user's own human body.

  Improvement of operability is an important issue for a user interface, and it is always required to be able to input more diverse information more easily.

  The present invention has been made in view of such a situation, and by realizing a user interface for specifying the position of a human body in a space by using an electrostatic field, it is possible to make more diverse information easier. It allows you to enter.

  One aspect of the present invention is an information processing system including a transmission device, a reception device, and a communication medium, wherein the transmission device is an electrode pair including a first electrode and a second electrode, and the first electrode is A first electrode pair that forms a stronger electrostatic coupling with the space than the second electrode, wherein the second electrode forms a stronger electrostatic coupling with the first portion of the communication medium than the first electrode; A transmission unit that supplies a transmission signal as a potential difference between the first electrode and the second electrode, and the reception device is an electrode pair including a third electrode and a fourth electrode, and the third electrode Forming a stronger electrostatic coupling with the space than the fourth electrode, and the fourth electrode forming a stronger electrostatic coupling with the second portion of the communication medium than the third electrode. And at least two sets of reception units that generate reception signals from the potential difference between the third electrode and the fourth electrode, and at least Signal strength measuring means for measuring the signal strength of the received signal obtained from the pair of receiving units, and position specifying means for specifying the position of the communication medium based on the signal strength of each received signal measured by the signal strength measuring means Is an information processing system.

  The signal transmitted between the transmitting device and the receiving device may include an information signal.

  In each of the first receiving unit group and the second receiving unit group that are sets of receiving units, the fourth electrode of the first receiving unit group and the fourth electrode of the second receiving unit group are perpendicular to each other. Can be arranged.

  In the first receiving unit group and the second receiving unit group, which are sets of receiving units, respectively, the fourth electrode of the first receiving unit group and the fourth electrode of the second receiving unit group are communication media. It can arrange | position so that it may be pinched | interposed.

  The second electrode and the fourth electrode are arranged so that signal transmission is possible even in the absence of a communication medium, and the position specifying means includes a signal transmission characteristic when there is no communication medium, and a communication medium. The position of the communication medium can be specified based on the difference from the signal transfer characteristic in the case where there is.

  Another aspect of the present invention is an electrode pair comprising a first electrode and a second electrode, wherein the first electrode forms a stronger electrostatic coupling with the space than the second electrode, From the potential difference between the first electrode and the second electrode, the electrode pair forming the electrostatic coupling with the predetermined part of the communication medium stronger than the second electrode, and from the transmitter via the communication medium At least two sets of reception units that generate reception signals that are reception results of the signals transmitted in this manner, signal strength measurement means that measures the signal strength of the reception signals obtained in at least two sets of reception units, and signal strength measurement And a position specifying means for specifying the position of the communication medium based on the signal strength of each received signal measured by the means.

  Information extraction means for extracting information transmitted from the transmission device included in the reception signals obtained by the at least two sets of reception units may be further provided.

  The at least two sets of receiving units are grouped into two groups, the second electrode of the first receiving unit group as one group and the second electrode of the second receiving unit group as the other group Can be arranged perpendicular to each other.

  The at least two sets of receiving units are grouped into two groups, the second electrode of the first receiving unit group as one group and the second electrode of the second receiving unit group as the other group Can be arranged so as to sandwich the operation area of the communication medium.

  The second electrode is one electrode of the electrode pair of the transmission device, and forms a stronger electrostatic coupling with a predetermined part of the communication medium than the other electrode of the electrode pair, and transmits a signal to the communication medium. The position specifying means may determine the position of the communication medium based on a difference between the signal transfer characteristic when the communication medium is not present and the signal transfer characteristic when the communication medium is present. it can.

  Another aspect of the present invention is an electrode pair comprising a first electrode and a second electrode, wherein the first electrode forms a stronger electrostatic coupling with the space than the second electrode, From the potential difference between the first electrode and the second electrode, the electrode pair forming the electrostatic coupling with the predetermined part of the communication medium stronger than the second electrode, and from the transmitter via the communication medium And a reception method for receiving a signal transmitted from a transmission device, the reception method including at least two sets of reception units that generate reception signals that are reception results of the signals transmitted in the reception method. The reception method includes a step of measuring the signal strength of the reception signal obtained in the section and specifying the position of the communication medium based on the signal strength of each reception signal measured by the processing of the signal strength measurement step.

  Another aspect of the present invention is an electrode pair comprising a first electrode and a second electrode, wherein the first electrode forms a stronger electrostatic coupling with the space than the second electrode, From the potential difference between the first electrode and the second electrode, the electrode pair forming the electrostatic coupling with the predetermined part of the communication medium stronger than the second electrode, and from the transmitter via the communication medium And at least two sets of receiving units that generate reception signals that are reception results of the signals transmitted by the receiver, and a program that performs processing of the reception device that receives signals transmitted from the transmission device. Measures the signal strength of the received signal obtained at the receiving section of the computer, and causes the computer to execute a step of specifying the position of the communication medium based on the signal strength of each received signal measured by the signal strength measuring step processing It is.

  In one aspect of the present invention, signal strengths of received signals obtained by at least two sets of receiving units are measured, and a position of a communication medium is specified based on the measured signal strengths of the received signals.

  According to an aspect of the present invention, information can be received. In particular, it is possible to realize a user interface for specifying the position of a human body in a space using an electrostatic field, and to input more diverse information more easily.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. First, referring to FIG. 1 to FIG. 33, as an example of a communication system to which the present invention is applied, a physical reference point path is not required and communication using only a communication signal transmission path is realized. A communication system that is not restricted will be described.

  FIG. 1 is a diagram illustrating a configuration example according to an embodiment of a communication system that performs communication using only a communication signal transmission path without using a physical reference point path.

  In FIG. 1, the communication system 100 includes a transmission device 110, a reception device 120, and a communication medium 130, and the transmission device 110 and the reception device 120 transmit and receive signals via the communication medium 130. That is, in the communication system 100, the signal transmitted from the transmission device 110 is transmitted via the communication medium 130 and received by the reception device 120.

  The transmission device 110 includes a transmission signal electrode 111, a transmission reference electrode 112, and a transmission unit 113. The transmission signal electrode 111 is one electrode of an electrode pair provided for transmitting a signal to be transmitted through the communication medium 130, and the communication medium 130 is more than the transmission reference electrode 112 which is the other electrode of the electrode pair. Are provided so that electrostatic coupling is strong. The transmission unit 113 is provided between the transmission signal electrode 111 and the transmission reference electrode 112, and gives an electric signal (potential difference) to be transmitted to the reception device 120 between these electrodes.

  The reception device 120 includes a reception signal electrode 121, a reception reference electrode 122, and a reception unit 123. The reception signal electrode 121 is one electrode of an electrode pair provided for receiving a signal transmitted via the communication medium 130, and the communication medium is more than the reception reference electrode 122 which is the other electrode of the electrode pair. 130 is provided so that electrostatic coupling is strong. The reception unit 123 is provided between the reception signal electrode 121 and the reception reference electrode 122, detects an electric signal (potential difference) generated between these electrodes by a signal transmitted via the communication medium 130, and detects the electric signal. The signal is converted into a desired electrical signal, and the electrical signal generated by the transmission unit 113 of the transmission device 110 is restored.

  The communication medium 130 is made of a substance having physical characteristics capable of transmitting an electrical signal, such as a conductor or a dielectric. For example, the communication medium 130 is a conductor typified by a metal such as copper, iron, or aluminum, a dielectric typified by pure water, rubber, glass, or the like, or a living body that is a composite thereof, or saline. Like electrolytes, etc., it is made of a material having both properties as a conductor and properties as a dielectric. The communication medium 130 may have any shape, for example, a linear shape, a plate shape, a spherical shape, a prism shape, a cylindrical shape, or any other shape. Also good.

  In such a communication system 100, first, the relationship between each electrode and the communication medium or the space around the apparatus will be described. In the following, for convenience of explanation, it is assumed that the communication medium 130 is a complete conductor. Further, it is assumed that there is a space between the transmission signal electrode 111 and the communication medium 130 and between the reception signal electrode 121 and the communication medium 130 and there is no electrical coupling. That is, a capacitance is formed between the transmission signal electrode 111 or the reception signal electrode 121 and the communication medium 130.

  The transmission reference electrode 112 is provided so as to face the space around the transmission device 110, and the reception reference electrode 122 is provided so as to face the space around the reception device 120. Generally, when a conductor sphere exists in a space, a capacitance is formed between the conductor sphere and the space. For example, when the shape of the conductor is a sphere having a radius of r [m], the capacitance C is obtained as in the following formula (1).

  In the formula (1), π represents a circumference ratio. Further, ε represents a dielectric constant and is obtained as in the following formula (2).

However, in Formula (2), ε ₀ indicates a dielectric constant in a vacuum, and is 8.854 × 10 ⁻¹² [F / m]. Further, ε _r represents a relative dielectric constant, and represents a ratio to a vacuum dielectric constant ε ₀ .

  As shown in the above formula (1), the larger the radius r, the larger the capacitance C. In addition, although the magnitude | size of the electrostatic capacitance C of a conductor of complicated shape other than a sphere cannot be expressed simply like Formula (1) mentioned above, it changes according to the magnitude | size of the surface area of the conductor. It is clear to do.

  As described above, the transmission reference electrode 112 forms a capacitance with respect to the space around the transmission device 110, and the reception reference electrode 122 forms a capacitance with respect to the space around the reception device 120. That is, when viewed from the virtual infinity point outside the transmission device 110 and the reception device 120, the potential of the transmission reference electrode 112 and the reception reference electrode 122 increases with the increase in capacitance. Is shown.

  Next, the principle of communication in the communication system 100 will be described. In the following description, a capacitor may be simply expressed as a capacitance for convenience of explanation or from the context, etc., but these are consents.

  In the following description, it is assumed that the transmission device 110 and the reception device 120 in FIG. 1 are arranged so as to maintain a sufficient distance between the devices, and the mutual influence can be ignored. Further, in the transmission device 110, the transmission signal electrode 111 is electrostatically coupled only to the communication medium 130, and the transmission reference electrode 112 is placed at a sufficient distance from the transmission signal electrode 111, and the mutual influence can be ignored (electrostatic). Shall not be combined). Similarly, in the receiving device 120, the reception signal electrode 121 is electrostatically coupled only with the communication medium 130, and the reception reference electrode 122 is sufficiently spaced from the reception signal electrode 121, and the mutual influence can be ignored (static). Shall not be electrocoupled). Furthermore, in practice, the transmission signal electrode 111, the reception signal electrode 121, and the communication medium 130 also have capacitance to the space as long as they are arranged in the space, but here, for convenience of explanation. , They can be ignored.

  FIG. 2 is a diagram illustrating the communication system 100 of FIG. 1 with an equivalent circuit. The communication system 200 is an equivalent circuit of the communication system 100 and is substantially equivalent to the communication system 100.

  That is, the communication system 200 includes a transmission device 210, a reception device 220, and a connection line 230. The transmission device 210 corresponds to the transmission device 110 of the communication system 100 shown in FIG. Corresponds to the receiving device 120 of the communication system 100 shown in FIG. 1, and the connection line 230 corresponds to the communication medium 130 of the communication system 100 shown in FIG.

  In the transmission device 210 of FIG. 2, the signal source 213-1 and the reference point 213-2 within the transmission device correspond to the transmission unit 113 of FIG. The signal source 213-1 generates a sine wave having a specific period ω × t [rad] as a transmission signal. Here, t [s] indicates time. Further, ω [rad / s] represents an angular frequency and can be expressed as the following equation (3).

  In Expression (3), π represents a circular ratio, and f [Hz] represents a frequency of a signal generated by the signal source 213-1. The reference point 213-2 in the transmission device is a point connected to the circuit ground in the transmission device 210. That is, one of the terminals of the signal source 213-1 is set to a predetermined reference potential of a circuit in the transmission device 210.

  Cte 214 is a capacitor and represents the capacitance between the transmission signal electrode 111 and the communication medium 130 of FIG. In other words, the Cte 214 is provided between the connection line 230 and the terminal of the signal source 213-1 on the opposite side to the reference point 213-2 in the transmission apparatus. Further, Ctg 215 is a capacitor and represents the capacitance with respect to the space of the transmission reference electrode 112 in FIG. The Ctg 215 is provided between a terminal on the reference point 213-2 in the transmission apparatus of the signal source 213-1 and a reference point 216 that indicates an infinite point (virtual point) with respect to the transmission apparatus 210 in space. I have.

  In the receiving device 220 of FIG. 2, Rr 223-1, detector 223-2, and in-receiving device reference point 223-3 correspond to the receiving unit 123 of FIG. Rr 223-1 is a load resistance (reception load) for extracting a reception signal. A detector 223-2 configured by an amplifier detects and amplifies the potential difference between the terminals on both sides of the Rr 223-1. The receiving device reference point 223-3 is a point connected to the circuit ground in the receiving device 220. That is, one of the terminals of Rr 223-1 (one of the input terminals of the detector 223-2) is set to a predetermined reference potential of the circuit in the receiving device 220.

  The detector 223-2 may further have other functions such as demodulating the detected modulated signal and decoding encoded information included in the detected signal. Good.

  Cre 224 is a capacitor and represents the capacitance between the reception signal electrode 121 and the communication medium 130 of FIG. That is, Cre 224 is provided between the terminal opposite to reference point 223-3 in the receiving device of Rr 223-1 and connection line 230. Crg 225 is a capacitor and represents the capacitance with respect to the space of the reception reference electrode 122 in FIG. The Crg 225 is provided between the terminal on the reference point 223-3 in the receiving device of the Rr 223-1 and the reference point 226 that indicates an infinite point (virtual point) with respect to the receiving device 120 in space. Yes.

  The connection line 230 represents the communication medium 130 that is a perfect conductor. In the communication system 200 of FIG. 2, Ctg 215 and Crg 225 are expressed as being electrically connected to each other via a reference point 216 and a reference point 226 on an equivalent circuit. These do not need to be electrically connected to each other, and each of them only needs to form a capacitance with respect to the space around the transmitter 210 or the receiver 220. If there is a conductor, it is important that a capacitance proportional to the size of the surface area is always formed in the surrounding space. Note that the reference point 216 and the reference point 226 do not need to be electrically connected and may be independent of each other.

  Further, when the communication medium 130 of FIG. 1 is a perfect conductor, the conductivity of the connection line 230 can be regarded as infinite, so the length of the connection line 230 of FIG. 2 does not affect communication. If the communication medium 130 is a conductor having sufficient conductivity, the distance between the transmission device and the reception device does not affect the stability of communication in practice. Therefore, in such a case, the distance between the transmission device 210 and the reception device 220 may be as long as possible.

In the communication system 200, a circuit including a signal source 213-1, Rr 223-1, Cte 214, Ctg 215, Cre 224, and Crg 225 is formed. The combined capacitance C _x of the four capacitors (Cte 214, Ctg 215, Cre capacitor 224, and Crg 225) connected in series can be expressed by the following equation (4).

Further, the sine wave v _t (t) generated by the signal source 213-1 is expressed as the following equation (5).

Here, V _m [V] represents the maximum amplitude voltage of the signal source voltage, and θ [rad] represents the initial phase angle. At this time, the effective value V _trms [V] of the voltage by the signal source 213-1 can be obtained as in the following equation (6).

  The synthetic impedance Z in the entire circuit can be obtained as in the following equation (7).

That is, the effective value V _{rrms of the} voltage generated at both ends of _{Rr 223-1} can be obtained as shown in Expression (8).

Therefore, as shown in the equation (8), as the resistance value of Rr 223-1 is larger, the capacitance C _x is larger, and the frequency f [Hz] of the signal source 213-1 is higher, 1 / ( The term (2 × π × f × C _x ) ² ) is reduced, and a larger signal can be generated at both ends of Rr 223-1.

For example, the effective value V _trms of the voltage by the signal source 213-1 of the transmission device 210 is fixed to 2 [V], and the frequency f of the signal generated by the signal source 213-1 is 1 [MHz], 10 [MHz], Or 100 [MHz], the resistance value of Rr 223-1 is 10 [KΩ], 100 [KΩ], or 1 [MΩ], and the capacitance C _x of the entire circuit is 0.1 [pF], 1 [pF ] Or 10 [pF], the calculation result of the effective value V _rrms of the voltage generated at both ends of _{Rr 223-1} is as shown in Table 250 shown in FIG.

As shown in Table 250, when the other conditions are the same, the calculation result of the voltage effective value V _rrms is _larger when the frequency f is 10 [MHz] than when the frequency f is 1 [MHz]. The resistance value of the load Rr 223-1 is larger when the resistance value is 1 [MΩ] than when the resistance value is 10 [KΩ], and is 10 [pF] than when the capacitance C _x is 0.1 [pF]. Time takes a larger value. That is, the larger the value of frequency f, the resistance value of Rr 223-1, and the capacitance C _x , the larger the effective value V _{rrms of the} voltage.

  Further, it can be seen from Table 250 that an electrical signal is generated in Rr 223-1 even with a capacitance of picofarad or less. That is, when the signal level of the transmitted signal is very small, communication can be performed by amplifying the signal detected by the detector 223-2 of the receiving device 220.

  Next, a calculation example of each parameter of the communication system 200 having the equivalent circuit described above will be specifically described with reference to FIG. FIG. 4 is a diagram for explaining a calculation example including the influence of the physical configuration of the communication system 100.

  A communication system 300 shown in FIG. 4 is a system corresponding to the communication system 100 of FIG. 1, and is obtained by adding information related to the physical configuration of the communication system 100 to the communication system 200 of FIG. That is, the communication system 300 includes a transmission device 310, a reception device 320, and a communication medium 330. In comparison with the communication system 100 in FIG. 1, the transmission device 310 corresponds to the transmission device 110, the reception device 320 corresponds to the reception device 120, and the communication medium 330 corresponds to the communication medium 130.

  The transmission device 310 includes a transmission signal electrode 311 corresponding to the transmission signal electrode 111, a transmission reference electrode 312 corresponding to the transmission reference electrode 112, and a signal source 313-1 corresponding to the transmission unit 113. That is, the transmission signal electrode 311 is connected to one of the terminals on both sides of the signal source 313-1 and the transmission reference electrode 312 is connected to the other. The transmission signal electrode 311 is provided so as to be close to the communication medium 330. The transmission reference electrode 312 is provided so as not to be influenced by the communication medium 330, and is provided so as to have a capacitance with respect to a space outside the transmission device 310. In FIG. 2, the transmission unit 113 has been described so that the signal source 213-1 and the reference point 213-2 in the transmission apparatus correspond to each other. However, in the case of FIG. Dots are omitted.

  Similarly to the case of the transmission device 310, the reception device 320 also includes the reception signal electrode 321 corresponding to the reception signal electrode 121, the reception reference electrode 322 corresponding to the reception reference electrode 122, the Rr 323-1 corresponding to the reception unit 123, and the detection. It has a device 323-2. That is, the reception signal electrode 321 is connected to one of the terminals on both sides of the Rr 323-1 and the reception reference electrode 322 is connected to the other. The reception signal electrode 321 is provided so as to be close to the communication medium 330. The reception reference electrode 322 is provided so as not to be affected by the communication medium 330, and is provided so as to have a capacitance with respect to a space outside the reception device 320. In FIG. 2, the receiving unit 123 has been described so that the Rr 223-1, the detector 223-2, and the reference point 223-3 in the receiving apparatus correspond to each other. However, in the case of FIG. In-apparatus reference points are omitted.

  It is assumed that the communication medium 330 is a complete conductor as in the case of FIGS. The transmitting device 310 and the receiving device 320 are arranged at a sufficient distance from each other, and the mutual influence can be ignored. The transmission signal electrode 311 is electrostatically coupled only to the communication medium 330. Further, the transmission reference electrode 312 is disposed with a sufficient distance from the transmission signal electrode 311, and the mutual influence can be ignored. Similarly, the reception signal electrode 321 is electrostatically coupled only to the communication medium 330. Further, the reception reference electrode 322 is disposed with a sufficient distance from the reception signal electrode 321, and the mutual influence can be ignored. Strictly speaking, the transmission signal electrode 311, the reception signal electrode 321, and the communication medium 330 have a capacitance with respect to space, but here, for convenience of explanation, these can be ignored.

  As shown in FIG. 4, in the communication system 300, the transmission device 310 is disposed at one end of the communication medium 330 and the reception device 320 is disposed at the other end.

It is assumed that there is a distance dte [m] between the transmission signal electrode 311 and the communication medium 330. Further, when the transmission signal electrode 311 is a conductor disk having a surface area of Ste [m ² ] on one side, a capacitance Cte 314 formed between the transmission medium 330 and the communication medium 330 is obtained by the following equation (9). I can do it.

Formula (9) is a calculation formula generally known as the capacitance of a parallel plate. In the above equation, ε represents a dielectric constant. Now, assuming that the communication system 300 is placed in the air, the relative dielectric constant ε _r can be regarded as approximately 1. Therefore, the dielectric constant ε is a dielectric constant in a vacuum. It can be regarded as equivalent to ε ₀ . The transmission signal electrode 311 has a surface area Ste of 2 × 10 ⁻³ [m ² ] (diameter of about 5 [cm]) and an interval dte of 5 × 10 ⁻³ [m] (5 [mm]). Is obtained as shown in the following equation (10).

  Note that the above equation (9) is strictly established as an actual physical phenomenon when the relationship of Ste >> dte is satisfied, but here it can be approximated by the equation (9). .

  Next, the capacitance Ctg 315 including the transmission reference electrode 312 and the space (capacitance between the transmission reference electrode 312 and the reference point 316 indicating a virtual infinity point from the transmission reference electrode 312) will be described. . In general, when a disk having a radius r [m] is placed in a space, the capacitance C [F] formed between the disk and the space can be obtained by the following equation (11). .

If the transmission reference electrode 312 is a conductor disk having a radius rtg = 2.5 × 10 ⁻² [m] (radius 2.5 [cm]), a capacitance Ctg 315 including a transmission reference electrode 317 and a space is Using the above equation (11), the following equation (12) is obtained. Note that the communication system 300 is placed in the air, and the dielectric constant of the space can be approximated by a vacuum dielectric constant ε ₀ .

The size of the reception signal electrode 321 is the same as that of the transmission signal electrode 311 (conductor disk of Sre [m ² ] = Ste [m ² ]), and the distance from the communication medium 330 is also the same (dre [m] = dte [m ]), The electrostatic capacity Cre 324 including the reception signal electrode 321 and the communication medium 330 is 3.5 [pF] as in the transmission side. Further, if the size of the reception reference electrode 322 is the same as that of the transmission reference electrode 312 (a conductor disk having a radius rrg [m] = rtg [m]), the capacitance (reception reference) including the reception reference electrode 322 and a space. The capacitance (Crg 325) between the electrode 322 and the reference point 326 indicating a virtual infinity point from the reception reference electrode 322 is 1.8 [pF] as in the transmission side. From the above, the combined electrostatic capacitance C _x composed of the four electrostatic capacitances of Cte 314, Ctg 315, Cre 324, and Crg 325 can be obtained as the following equation (13) using the above equation (4).

When the frequency f of the signal source 313-1 is 1 [MHz], the effective value V _{trms of the} voltage is 2 [V], and Rr323-1 is 100 K [Ω], the voltage V _rrms generated at both ends of the _Rr323-1 is The following equation (14) can be obtained.

  From the above results, as a basic principle, it is possible to transfer a signal from the transmission device to the reception device by using the capacitance formed with the space.

  The capacitance with respect to the space of the transmission reference electrode and the reception reference electrode described above can be formed if there is a space at the position of each electrode. Therefore, if the transmission signal electrode and the reception signal electrode described above are coupled by a communication medium, the transmission device and the reception device described above can obtain communication stability without depending on the distance between each other.

  Next, the case where this communication system is actually configured will be described. FIG. 5 is a diagram illustrating an example of a calculation model for each parameter generated on the system when the communication system described above is actually physically configured.

  That is, the communication system 400 includes the transmission device 410, the reception device 420, and the communication medium 430, and is a system corresponding to the communication system 100 (the communication system 200 and the communication system 300) described above. The configuration is basically the same as that of the communication system 100 to the communication system 300 except for the difference.

  That is, in comparison with the communication system 300, the transmission device 410 corresponds to the transmission device 310, the transmission signal electrode 411 of the transmission device 410 corresponds to the transmission signal electrode 311, and the transmission reference electrode 412 corresponds to the transmission reference electrode 312. Correspondingly, the signal source 431-1 corresponds to the signal source 331-1. In addition, the reception device 420 corresponds to the reception device 320, the reception signal electrode 421 of the reception device 420 corresponds to the reception signal electrode 321, the reception reference electrode 422 corresponds to the reception reference electrode 322, and Rr423-1 corresponds to Rr323-1. The detector 423-2 corresponds to the detector 323-2. Further, the communication medium 430 corresponds to the communication medium 330.

The parameters Cte 414 between the transmission signal electrode 411 and the communication medium 430 correspond to the Cte 314 of the communication system 300, and the capacitance Ctg 415 with respect to the space of the transmission reference electrode 412 is the Ctg 315 of the communication system 300. , And reference point 416-1 and reference point 416-2 indicating a virtual infinity point in space from transmitting apparatus 410 correspond to reference point 316 of communication system 300. The transmission signal electrode 411 is a disk-shaped electrode having an area Ste [m ² ], and is provided at a position separated from the communication medium 430 by a minute distance dte [m]. The transmission reference electrode 412 is also a disk-like electrode, and its radius is rtg [m].

On the receiving device 420 side, the electrostatic capacity Cre 424 between the reception signal electrode 421 and the communication medium 430 corresponds to Cre 324 of the communication system 300, and the electrostatic capacity Crg 425 with respect to the space of the reception reference electrode 422 corresponds to the Crg 325 of the communication system 300. Correspondingly, a reference point 426-1 and a reference point 426-2 indicating a virtual infinity point in space from the receiving apparatus 420 correspond to the reference point 326 of the communication system 300. The reception signal electrode 421 is a disk-shaped electrode having an area Sre [m ² ], and is provided at a position separated from the communication medium 430 by a minute distance dre [m]. The reception reference electrode 422 is also a disk-shaped electrode, and its radius is rrg [m].

  The communication system 400 of FIG. 5 is a model in which the following new parameters are added to the above parameters.

  For example, with respect to the transmission device 410, a capacitance Ctb 417-1 formed between the transmission signal electrode 411 and the transmission reference electrode 412, and a capacitance Cth 417-2 formed between the transmission signal electrode 411 and the space. , And a capacitance Cti 417-3 formed between the transmission reference electrode 412 and the communication medium 430 is added as a new parameter.

  As for the receiving device 420, an electrostatic capacitance Crb 427-1 formed between the reception signal electrode 421 and the reception reference electrode 422, and an electrostatic capacitance Crh 427-2 formed between the reception signal electrode 421 and the space. , And a capacitance Cri427-3 formed between the reception reference electrode 422 and the communication medium 430 is added as a new parameter.

  Further, with respect to the communication medium 430, an electrostatic capacitance formed between the communication medium 430 and the space (a static point between the communication medium 430 and a reference point 436 indicating a virtual infinity point from the communication medium 430). Electric capacity) Cm 432 is added as a new parameter. Actually, since the communication medium 430 has an electric resistance depending on its size, material, and the like, resistance values Rm431 and Rm433 are added as new parameters as resistance components.

  Although omitted in the communication system 400 of FIG. 5, when the communication medium has not only conductivity but also dielectric properties, a capacitance according to the dielectric constant is also formed. In addition, when the communication medium is not conductive and is formed only of dielectric, an electrostatic capacitance determined by the dielectric constant, distance, size, and arrangement of the dielectric between the transmission signal electrode 411 and the reception signal electrode 421. It will be coupled by capacity.

  In addition, here, when the transmission device 410 and the reception device 420 are separated from each other to such an extent that the electrostatic coupling elements can be ignored (the influence of electrostatic coupling between the transmission device 410 and the reception device 420). (If it can be ignored). If the distance is short, it may be necessary to consider the electrostatic capacitance between the electrodes in the transmitter 410 and the electrodes in the receiver 420 according to the above-described concept. is there.

  Next, the operation of the communication system 400 of FIG. 5 will be described using electric lines of force. FIG. 6 and FIG. 7 are schematic diagrams expressing the relationship between the electrodes of the transmission device 410 of the communication system 400 or between the electrodes and the communication medium 430 using lines of electric force.

  FIG. 6 is a schematic diagram illustrating an example of the distribution of lines of electric force when the communication medium 430 does not exist for the transmission device 410 of the communication system 400. Now, it is assumed that the transmission signal electrode 411 has a positive charge (positively charged), and the transmission reference electrode 412 has a negative charge (negatively charged). The arrows in the figure indicate lines of electric force, and the direction is from positive charges to negative charges. The electric field lines do not disappear suddenly on the way, and have either the property of reaching an object having a charge with an opposite sign or reaching a virtual infinity point.

  Here, the electric lines of force 451 indicate the electric lines of force emitted from the transmission signal electrode 411 that have reached the infinity point. The electric lines of force 452 indicate lines of electric force reaching the transmission reference electrode 412 that reach the virtual infinity point. The electric lines of force 453 indicate electric lines of force generated between the transmission signal electrode 411 and the transmission reference electrode 412. The distribution of these lines of electric force is affected by the size and positional relationship of each electrode.

  FIG. 7 is a schematic diagram illustrating an example of the distribution of lines of electric force when the communication medium 430 is brought close to such a transmission apparatus 410. Since the communication medium 430 approaches the transmission signal electrode 411, the coupling between the two becomes stronger, and many of the electric force lines 451 that have reached the infinity point in FIG. 6 become electric force lines 461 that reach the communication medium 430. The electric force line 463 to the point at infinity (the electric force line 451 in FIG. 6) decreases. Accordingly, the capacitance (Cth 417-2 in FIG. 5) with respect to the infinity point when viewed from the communication signal electrode 411 is weakened, and the capacitance with the communication medium 430 (Cte 414 in FIG. 5) is increased. In practice, there is also electrostatic coupling (Cti 417-3 in FIG. 5) between the transmission reference electrode 412 and the communication medium 430, but it can be ignored here.

  According to Gauss's law, the number N of lines of electric force exiting through any closed surface S is equal to the total charge contained in the closed surface S divided by the dielectric constant ε. The charge outside the closed curved surface S is not affected. When n charges are present on the closed curved surface S, the following equation is established.

Here, i is an integer. The variable q _i indicates the charge amount of each charge. According to this law, the electric lines of force that spring out from the closed curved surface S are determined only by the electric lines of force generated from the charges existing in the closed curved surface S, and all the electric lines of force that enter from the outside are from different places. Indicates going out.

  According to this law, if the communication medium 430 is not grounded in FIG. 7, there is no charge generation source on the closed curved surface 471 near the communication medium 430. In the region 472, a charge Q3 is induced by electrostatic induction. Since the communication medium 430 is not grounded, the total charge amount of the communication medium 430 does not change. Therefore, in the region 473 outside the region 472 in which the charge Q3 is induced, the charge Q4 having the same amount and different sign is present. The electric lines of force 464 that are induced and thereby exit from the closed curved surface 471. The charge Q4 is more diffused as the communication medium is larger, and the charge density is also reduced. Accordingly, the number of electric lines of force per unit area is also reduced.

In the case where the communication medium 430 is a perfect conductor, due to the property of the perfect conductor, there is a property that the electric potential density is almost the same regardless of the part due to the characteristic that the potential is the same regardless of the part. When the communication medium 430 is a conductor having a resistance component, the number of electric lines of force also decreases according to the distance according to the resistance component. When the communication medium 430 is a dielectric material having no conductivity, the electric lines of force are diffused and propagated by the polarization action. When n conductors are present in the space, the charge Q _i of each conductor can be obtained by the following equation.

Here, i and j are integers, and C _ij represents a capacitance coefficient composed of the conductor i and the conductor j, and may be considered to have the same property as the capacitance. The capacitance coefficient is determined only from the shapes of the conductors and their positional relationship. The capacitance coefficient C _ii is a capacitance that the conductor i itself forms with respect to the space. Also, C _ij = C _ji . In equation (16), it is shown that a system composed of a plurality of conductors operates based on the principle of superposition, and corresponds to the sum of products of the capacitance between conductors and the potential of each conductor. It is shown that the electric charge of the conductor is determined.

  Now, parameters related to each other in FIG. 7 and Expression (16) are determined as follows. For example, Q1 represents the charge induced in the transmission signal electrode 411, Q2 represents the charge induced in the transmission reference electrode 412, and Q3 represents the charge induced in the communication medium 430 by the transmission signal electrode 411. , Q4 represents a charge on the communication medium 430 having the same sign as the charge Q3.

  In addition, V1 represents the potential of the transmission signal electrode 411 with respect to the infinity point, V2 represents the potential of the transmission reference electrode 412 with respect to the infinity point, and V3 represents the communication medium 430. , C12 represents a capacitance coefficient between the transmission signal electrode 411 and the transmission reference electrode 412, C13 represents a capacitance coefficient between the transmission signal electrode 411 and the communication medium 430, and C15 Indicates the transmission signal electrode 411 and the space capacitance coefficient, C25 indicates the transmission signal electrode 411 and the space capacitance coefficient, and C45 indicates the communication medium 430 and the space capacitance coefficient.

  At this time, the charge Q3 can be obtained as follows.

  In order to inject more electric field into the communication medium 430, the charge Q3 may be increased. For this purpose, the capacitance coefficient C13 between the transmission signal electrode 411 and the communication medium 430 is increased, and a sufficient potential V1 is set. Give it. The capacitance coefficient C13 is determined only by the shape and the positional relationship, but the capacitance increases as the distance between them is closer and the facing area is larger. Next, the potential is V1, and this potential needs to be sufficiently generated when viewed from the infinity point. When viewed from the transmission device 410, a potential difference is given between the transmission signal electrode 411 and the transmission reference electrode 412 by the signal source. In order to generate this potential difference as a sufficient potential difference even when viewed from the infinity point, The behavior of the transmission reference electrode 412 becomes important.

  If the transmission reference electrode 412 is very small and the transmission signal electrode 411 is sufficiently large, the capacitance coefficients C12 and C25 are small. On the other hand, since the capacitance coefficients C13, C15, and C45 have a large capacitance, they are less likely to fluctuate electrically, and most of the potential difference generated by the signal source appears as the potential V2 of the transmission reference electrode 412 and is transmitted. The potential V1 of the signal electrode 411 is reduced.

  This is shown in FIG. Since the transmission reference electrode 481 is minute, it does not couple with any conductor or infinity point. The transmission signal electrode 411 forms a capacitance Cte with the communication medium 430 and forms a capacitance Cth 417-2 with respect to the space. Further, the communication medium 430 forms a capacitance Cm 432 with respect to the space. Even if a potential is generated at the transmission signal electrode 411 and the transmission reference electrode 412, the capacitances Cte 414, Cth 417-2, and Cm 432 related to the transmission signal electrode 411 are overwhelmingly large. Although energy is required, since the capacitance of the transmission reference electrode 481 on the opposite side of the signal source 413-1 is weak, the potential of the transmission signal electrode 411 hardly changes and most of the potential fluctuation of the signal source 413-1 does not change. Appears on the transmission reference electrode 481 side.

  On the other hand, if the transmission signal electrode 411 is very small and the transmission reference electrode 481 is sufficiently large, the capacitance of the transmission reference electrode 481 increases and the transmission signal electrode 411 is less likely to fluctuate electrically. Although a sufficient potential V1 is generated, a sufficient electric field cannot be injected because the electrostatic coupling with the communication medium 430 is weakened.

  Therefore, it is necessary to provide a transmission reference electrode that can provide a sufficient potential while injecting an electric field necessary for communication from the transmission signal electrode into the communication medium in the overall balance. Here, only the transmission side is considered, but the same can be considered between the electrode of the reception device 420 and the communication medium 430 in FIG.

  The infinity point does not have to be physically far away, and in practice it is only necessary to consider the space around the device, but more ideally, the potential fluctuation is more stable in the system as a whole. It is desirable that there is little. Under actual usage conditions, there are noises generated from AC power lines, lighting equipment, and other electrical equipment, but these noises do not overlap at least in the frequency band used by the signal source or can be ignored. Good.

  FIG. 9 is a diagram showing an equivalent circuit of the model (communication system 400) shown in FIG. That is, as in the relationship between FIGS. 2 and 4, the communication system 500 illustrated in FIG. 9 corresponds to the communication system 400 illustrated in FIG. 5, and the transmission device 510 of the communication system 500 is connected to the transmission device 410 of the communication system 400. Correspondingly, the receiving device 520 of the communication system 500 corresponds to the receiving device 420 of the communication system 400, and the connection line 530 of the communication system 500 corresponds to the communication medium 430 of the communication system 400.

  Similarly, in the transmission apparatus 510 of FIG. 9, the signal source 513-1 corresponds to the signal source 413-1. In the transmission apparatus 510 of FIG. 9, the transmission apparatus internal reference indicating the ground in the circuit inside the transmission unit 113 of FIG. 1, corresponding to the transmission apparatus reference point 213-2 of FIG. Point 513-2 is shown.

  Further, Cte 514 in FIG. 9 is a capacitance corresponding to Cte 414 in FIG. 5, Ctg 515 is a capacitance corresponding to Ctg 415 in FIG. 5, and the reference point 516-1 and the reference point 516-2 are These correspond to the reference point 416-1 and the reference point 416-2, respectively. Further, Ctb 517-1 is a capacitance corresponding to Ctb 417-1, Cth 517-2 is a capacitance corresponding to Cth 417-2, and Cti 517-3 is a capacitance corresponding to Cti 417-3.

  The same applies to each part of the receiving device 520, and Rr 523-1 and detector 523-2, which are reception resistors, correspond to Rr 423-1 and detector 423-2 in FIG. 5, respectively. In the receiving apparatus 520 in FIG. 9, the reference in the receiving apparatus that indicates the ground in the circuit in the receiving unit 123 in FIG. 1 corresponding to the reference point 223-3 in the receiving apparatus in FIG. Point 523-3 is shown.

  In addition, Cre 524 in FIG. 9 is a capacitance corresponding to Cre 424 in FIG. 5, Crg 525 is a capacitance corresponding to Crg 425 in FIG. 5, and the reference point 526-1 and the reference point 526-2 are These correspond to the reference point 426-1 and the reference point 426-2, respectively. Furthermore, Crb527-1 is the capacitance corresponding to Crb427-1, Crh527-2 is the capacitance corresponding to Crh427-2, and Cri527-3 is the capacitance corresponding to Cri427-3.

  The same applies to each part connected to the connection line 530. Rm531 and Rm533, which are resistance components of the connection line, correspond to Rm431 and Rm433, Cm532 corresponds to Cm432, and the reference point 536 corresponds to the reference point 436, respectively. Correspond.

  Such a communication system 500 has the following properties.

  For example, the transmission device 510 can apply a larger signal to the connection line 530 corresponding to the communication medium 430 as the value of Cte 514 is larger (capacity is higher). Further, the transmission device 510 can apply a larger signal to the connection line 530 as the value of Ctg 515 is larger (capacity is higher). Further, the transmission device 510 can apply a larger signal to the connection line 530 as the value of Ctb 517-1 is smaller (capacity is lower). Further, the transmission device 510 can apply a larger signal to the connection line 530 as the value of Cth 517-2 is smaller (capacity is lower). Furthermore, the transmission device 510 can apply a larger signal to the connection line 530 as the value of Cti 517-3 is smaller (capacity is lower).

  The reception device 520 can extract a larger signal from the connection line 530 corresponding to the communication medium 430 as the value of Cre 524 is larger (capacity is higher). In addition, the receiving device 520 can extract a larger signal from the connection line 530 as the value of Crg 525 is larger (capacity is higher). Furthermore, the receiving device 520 can extract a larger signal from the connection line 530 as the value of Crb 527-1 is smaller (capacity is lower). In addition, the receiving device 520 can extract a larger signal from the connection line 530 as the value of Crh527-2 is smaller (capacity is lower). Furthermore, the receiving device 520 can extract a larger signal from the connection line 530 as the value of Cri527-3 is smaller (capacity is lower). In addition, the receiving device 520 can extract a larger signal from the connection line 530 as the value of Rr 523-1 is lower (resistance is higher).

  The transmission device 510 can apply a larger signal to the connection line 530 as the values of the resistance components Rm 531 and Rm 533 of the connection line 530 are lower (resistance is lower). In addition, the smaller the value of Cm 532 that is the capacitance with respect to the space of the connection line 530 (the lower the capacity), the more the transmitter 510 can apply a larger signal to the connection line 530.

  Since the size of the capacitor is roughly proportional to the surface area of the electrode, it is generally better to increase the size of each electrode. However, simply increasing the size of the electrode also increases the capacitance between the electrodes. There is also a risk of it. In addition, the efficiency may decrease even when the size ratio of the electrodes is extreme. Therefore, it is necessary to determine the size of the electrode and the location of the electrode within the overall balance.

  Note that the property of the communication device 500 described above is that, in the frequency band where the frequency of the signal source 513-1 is high, efficient communication is possible by capturing the equivalent circuit based on the concept of impedance matching and determining each parameter. Become. By increasing the frequency, reactance can be ensured even with a small capacitance, so that each device can be easily downsized.

  In general, the reactance of a capacitor increases as the frequency decreases. On the other hand, since the communication system 500 operates based on capacitive coupling, the lower limit of the frequency of the signal generated by the signal source 513-1 is determined thereby. Since Rm531, Cm532, and Rm533 form a low-pass filter based on the arrangement, the upper limit of the frequency is determined by this characteristic.

  That is, the frequency characteristic of the communication system 500 is as shown by a curve 551 in the graph shown in FIG. In FIG. 10, the horizontal axis indicates the frequency, and the vertical axis indicates the gain of the entire system.

  Next, specific numerical values of the parameters of the communication system 400 in FIG. 5 and the communication system 500 in FIG. 9 will be considered. In the following, for convenience of explanation, it is assumed that the communication system 400 (communication system 500) is installed in the air. Further, the transmission signal electrode 411, the transmission reference electrode 412, the reception signal electrode 421, and the reception reference electrode 422 of the communication system 400 (the transmission signal electrode 511, the transmission reference electrode 512, the reception signal electrode 521, and the reception reference electrode of the communication system 500). 522) is a conductor disk having a diameter of 5 cm.

  In the communication system 400 of FIG. 5, the capacitance Cte 414 (Cte 514 of FIG. 9) composed of the transmission signal electrode 411 and the communication medium 430 is given by the above-described equation (9) when the mutual distance dte is 5 mm. And obtained as the following equation (18).

  For Ctb 417-1 (Ctb 517-1 in FIG. 9), which is the capacitance between the electrodes, equation (9) can be applied. Originally, as described above, the equation is established when the area of the electrode is sufficiently larger than the interval, but here it may be approximated. When the distance between the electrodes is 5 cm, Ctb 417-1 (Ctb 517-1 in FIG. 9) is expressed by the following equation (19).

  The assumption here is that if the distance between the transmission signal electrode 411 and the communication medium 430 is narrow, the coupling with the space becomes weak, so the value of Cth 417-2 (Cht 517-2 in FIG. 9) is Cte 414 (Cte 514). It is assumed to be sufficiently smaller than the value of Cte 414 (Cte 514) as shown in the equation (20).

  Ctg 415 (Ctg 515 in FIG. 9) indicating the capacitance formed between the transmission reference electrode 412 and the space is the same as in FIG. 4 (Equation (12)), and can be obtained as in the following Equation (21). .

  The value of Cti417-3 (Cti517-3 in FIG. 9) is considered to be equivalent to Ctb417-1 (Ctb517-1 in FIG. 9) as follows.

  Cti = Ctb = 0.35 [pF]

  Regarding each parameter of the receiving device 420 (receiving device 520 in FIG. 9), if the configuration (size, installation position, etc.) of each electrode is the same as that of the transmitting device 410, each parameter of the transmitting device 410 is as follows. Set in the same way as parameters.

  Cre = Cte = 3.5 [pF] Crb = Ctb = 0.35 [pF] Crh = Cth = 0.35 [pF] Crg = Ctg = 1.8 [pF] Cri = Cti = 0.35 [pF]

  For convenience of explanation, it is assumed below that the communication medium 430 (connection line 530 in FIG. 9) is an object having characteristics similar to a living body of the size of a human body. The electrical resistance from the position of the transmission signal electrode 411 of the communication medium 430 to the position of the reception signal electrode 421 (the position of the transmission signal electrode 511 to the position of the reception signal electrode 521 in FIG. 9) is 1 [MΩ]. The values of Rm 431 and Rm 433 (Rm 531 and Rm 533 in FIG. 9) are set to 500 [KΩ], respectively. Further, the value of the capacitance Cm432 (Cm532 in FIG. 9) formed between the communication medium 430 and the space is set to 100 [pF].

  Further, the signal source 413-1 (the signal source 513-1 in FIG. 9) is a sine wave having a maximum value of 1 [V] and a frequency of 10 [MHz].

  When simulation is performed using the above parameters, a reception signal having a waveform as shown in FIG. 11 is obtained as a simulation result. In the graph shown in FIG. 11, the vertical axis represents the voltage across Rr 423-1 (Rr 523-1), which is the reception load of the receiving device 420 (the receiving device 520 in FIG. 9), and the horizontal axis represents time. . As indicated by a double-headed arrow 552 in FIG. 11, the difference (peak value difference) between the maximum value A and the minimum value B of the waveform of the received signal is observed at about 10 [μV]. Therefore, by amplifying this with an amplifier having a sufficient gain (detector 423-2), the signal on the transmission side (the signal generated in the signal source 413-1) can be restored on the reception side.

  As described above, the communication system to which the present invention is applied as described above does not require a physical reference point path and can realize communication using only the communication signal transmission path, and thus is not restricted by the use environment. A communication environment can be easily provided.

  Next, the arrangement of each electrode in each device will be described. As described above, each electrode has a different role and forms a capacitance with respect to a communication medium, space, or the like. In other words, each electrode is electrostatically coupled to a different partner, and acts using the electrostatic coupling. Therefore, the arrangement method of each electrode is a very important factor for effectively electrostatically coupling each electrode to the target object.

  For example, in the communication system 400 of FIG. 5, in order to efficiently communicate between the transmission device 410 and the reception device 420, it is necessary to arrange each electrode under the following conditions. That is, each device has sufficient capacitance between the transmission signal electrode 411 and the communication medium 430 and the capacitance between the reception signal electrode 421 and the communication medium 422, for example, Both the reference electrode 412 and the space capacitance, and the reception reference electrode 422 and the space capacitance are sufficient, the transmission signal electrode 411 and the transmission reference electrode 412, and the reception signal electrode 421. Between the transmission signal electrode 411 and the space, and the capacitance between the transmission signal electrode 411 and the space, and the capacitance between the reception signal electrode 421 and the space is smaller. Satisfy that. There is a need.

  Examples of the arrangement of the electrodes are shown in FIGS. Note that the electrode arrangement examples described below can be applied to both the transmission device and the reception device. Therefore, in the following, description of the receiving device is omitted, and only the transmitting device is described. When the example shown below is applied to a receiving device, the transmission signal electrode is made to correspond to the reception signal electrode, and the transmission reference electrode is made to correspond to the reception signal electrode.

  In FIG. 12, two electrodes of the transmission signal electrode 554 and the transmission reference electrode 555 are arranged on the same plane of the housing 553. According to this configuration, the capacitance between the electrodes can be reduced as compared with the case where the two electrodes (the transmission signal electrode 554 and the transmission reference electrode 555) are arranged to face each other. When using the transmission apparatus having such a configuration, only one of the two electrodes is brought close to the communication medium. For example, when the housing 553 is configured by two units and a hinge portion, and is connected via the hinge portion so that the relative angle between the two units is variable, the housing 553 is viewed as a whole. Suppose that the hinge 553 is a foldable portable telephone in which the casing 553 can be folded in the vicinity of the center in the longitudinal direction. By applying the electrode arrangement as shown in FIG. 12 to such a foldable mobile phone, one electrode is arranged on the back of the unit on the operation button side, and the other electrode is provided with a display unit. Can be placed on the back of the unit. By arranging in this way, the electrodes arranged in the unit on the operation button side are covered by the user's hand, and the electrodes provided on the back surface of the display unit are arranged facing the space. That is, two electrodes can be disposed so as to satisfy the above-described conditions.

  FIG. 13 shows a housing 553 in which two electrodes (a transmission signal electrode 554 and a transmission reference electrode 555) are arranged to face each other. In this case, compared with the arrangement of FIG. 12, although the electrostatic coupling between the two electrodes is strengthened, it is suitable when the housing 553 is relatively small. In this case, it is desirable that the two electrodes are arranged in a direction in which the distance is as far as possible in the housing 553.

  FIG. 14 shows a case in which two electrodes (a transmission signal electrode 554 and a transmission reference electrode 555) are arranged not to directly face each other in the housing 553, and are arranged on the surfaces of the housing 553 facing each other. In the case of this configuration, the electrostatic coupling between the two electrodes is smaller than that in FIG.

  FIG. 15 shows a case in which two electrodes (a transmission signal electrode 554 and a transmission reference electrode 555) are arranged in a casing 553 so as to be perpendicular to each other. According to this configuration, in a use in which the surface of the transmission signal electrode 554 and the opposite surface thereof are close to the communication medium, the side surface (surface on which the transmission reference electrode 555 is disposed) remains electrostatically coupled with the space. Is possible.

  FIG. 16 shows an arrangement in which the transmission reference electrode 555, which is one of the electrodes, is arranged inside the housing 553 in the arrangement shown in FIG. That is, as shown in FIG. 16A, only the transmission reference electrode 555 is provided inside the housing 553. FIG. 16B is a diagram illustrating an example of electrode positions when viewed from the surface 556 of FIG. 16A. As shown in FIG. 16B, the transmission signal electrode 554 is disposed on the surface of the housing 553, and only the transmission reference electrode 555 is installed inside the housing 553. According to this configuration, even if the housing 553 is widely covered with a communication medium, communication is possible because the space inside the housing 553 is around one electrode.

  FIG. 17 shows an arrangement in which the transmission reference electrode 555, which is one of the electrodes, is arranged inside the housing 553 in the arrangement shown in FIG. 12 or FIG. That is, as shown in FIG. 17A, only the transmission reference electrode 555 is provided inside the housing 553. FIG. 17B is a diagram illustrating an example of electrode positions when viewed from the surface 556 of FIG. 17A. As illustrated in FIG. 17B, the transmission signal electrode 554 is disposed on the surface of the housing 553, and only the transmission reference electrode 555 is disposed inside the housing 553. According to this configuration, even if the housing 553 is widely covered with a communication medium, communication is possible because there is room in the housing around one electrode.

  FIG. 18 shows an arrangement in which one of the electrodes is arranged inside the housing in the arrangement shown in FIG. That is, as shown in FIG. 18A, only the transmission reference electrode 555 is provided inside the housing 553. FIG. 18B is a diagram illustrating an example of electrode positions when viewed from the surface 556 of FIG. 18A. As shown in FIG. 18B, the transmission signal electrode 554 is disposed on the surface of the housing 553, and only the transmission reference electrode 555 is installed inside the housing 553. According to this configuration, even if the casing is widely covered with a communication medium, communication is possible because there is a space in the casing around the transmission reference electrode 555 that is one of the electrodes.

  In any of the electrode arrangements described above, the other electrode is closer to the communication medium than the one electrode, and the other electrode is arranged such that electrostatic coupling with the space is further enhanced. In each arrangement, it is desirable that the electrostatic coupling between the two electrodes be weakened.

  The transmission device or the reception device may be incorporated in some case. In the device of the present invention, there are at least two electrodes, and since these are electrically insulated, the casing is also made of an insulator having a certain thickness. FIG. 19 shows a sectional view around the transmission signal electrode. Since all of the transmission reference electrode, the reception signal electrode, and the reception reference electrode have the same configuration as the transmission signal electrode, the following description can be applied. Therefore, the description about them is omitted.

  FIG. 19A shows a cross-sectional view around the electrode. Since the housing 563 and the housing 564 always have a physical thickness (d [m]) indicated by the double arrow 565, the electrode and the communication medium (for example, the transmission electrode 561 and the communication medium 562), or the electrode At least a gap corresponding to this thickness is generated between the space. As apparent from the above description, it is generally more convenient to increase the capacitance between the electrode and the communication medium or between the electrode and the space.

  Consider a case where the communication medium 562 is in close contact with the housing 563 and the housing 564. In this case, the electrostatic capacitance C between the transmission reference electrode 561 and the communication medium 562 is obtained by (Equation 9), and therefore, the following equation (22) is obtained.

Here, ε ₀ is a vacuum dielectric constant and is a fixed value of 8.854 × 10 ⁻¹² [F / m]. ε _r is the relative dielectric constant of the place, and S is the surface area of the transmission signal electrode 561. By disposing a dielectric having a high relative dielectric constant in the space 566 formed above the transmission signal electrode 561, the capacitance can be increased and the performance can be improved.

  Similarly, the capacitance can be increased with respect to the surrounding space. In the case of FIG. 19A, the dielectric is inserted into the thickness (double arrow 565) portion of the housing, but this is not always necessary, and it may be at an arbitrary position.

  On the other hand, FIG. 19B shows an example in which the electrode is embedded in the housing. In FIG. 19B, the transmission signal electrode 561 is embedded in the housing 567 (so as to be a part of the housing 567). By doing so, the communication medium 562 contacts the housing 567 and simultaneously contacts the transmission signal electrode 561. Further, by forming an insulating layer on the surface of the transmission signal electrode 561, the communication medium 562 and the transmission signal electrode 561 can be brought into contact with each other.

  FIG. 19C shows a case in which the casing 567 is recessed with the surface area and thickness d ′ of the electrode and the transmission signal electrode 561 is embedded in the case of FIG. 19B. When the casing is integrally molded, this method can reduce the manufacturing cost and the component cost, and can easily increase the capacitance.

  According to the above description, for example, when a plurality of electrodes are arranged on the same plane as shown in FIG. 12, by inserting a dielectric on the transmission signal electrode 554 side (or on the transmission reference electrode 555 side). Even if the transmission signal electrode 554 and the transmission reference electrode 555 are combined with the communication medium (by inserting a dielectric having a high dielectric constant into the transmission signal electrode 554 side), the transmission signal electrode Since 554 is more strongly coupled to a communication medium, it is possible to communicate by generating a potential difference between the electrodes.

  Next, the size of the electrode will be described. At least the transmission reference electrode and the reception reference electrode need to form a capacitance with a sufficient space in order for the communication medium to obtain a sufficient potential, but the transmission signal electrode and the reception signal electrode are connected to the communication medium. In consideration of the electrostatic coupling and the nature of the signal to be sent to the communication medium, the optimum size may be set. Therefore, normally, the size of the transmission reference electrode is made larger than the size of the transmission signal electrode, and the size of the reception reference electrode is made larger than the size of the reception signal electrode. However, as long as sufficient signals are obtained for communication, other relationships may be used.

  In particular, when the size of the transmission reference electrode and the size of the transmission signal electrode are matched, and the size of the reception reference electrode and the size of the reception signal electrode are matched, these are seen from the reference point at the infinity point. The electrodes appear to have similar characteristics. For this reason, even if which electrode is used as the reference electrode (signal electrode) (even if the reference electrode and the signal electrode can be interchanged), there is a feature that an equivalent communication performance can be obtained.

  In other words, when the size of the reference electrode and the signal electrode is designed to be different from each other, the communication can be performed only when one electrode (the electrode set as the signal electrode) is brought close to the communication medium. Have

  Next, circuit shielding will be described. In the above, the transmitting unit and receiving unit other than the electrodes have been considered to be transparent in considering the physical configuration of the communication system. However, in order to actually realize this communication system, it is configured with electronic components and the like. It is common to be done. The electronic component is composed of a substance having some electrical properties such as conductivity and dielectric property. However, as long as these components exist around the electrodes, the operation is affected. In the present invention, the electrostatic capacity in the space has various influences, so the electronic circuit mounted on the substrate itself also gives and receives this influence. Therefore, when a more stable operation is expected, it is desirable to shield the whole with a conductor.

  Normally, the shielded conductor can be connected to the transmission reference electrode or the reception reference electrode, which is also the reference potential of the transmitter / receiver, but if there is no problem in operation, connect the shielded conductor to the transmission signal electrode or the reception signal electrode. Also good. Since the conductor of the shield itself has a physical size, it is necessary to consider that it operates in the interrelationship with other electrodes, communication media, and space in accordance with the principle described so far.

  FIG. 20 shows this embodiment. In this example, it is assumed that the device operates with a battery, and an electronic component including the battery is housed in a shield case 571, which also serves as a reference electrode. The electrode 572 is a signal electrode.

  Next, the communication medium will be described. As for the communication medium, in the examples so far, the conductor has been exemplified as the main example, but communication is possible even with a dielectric having no conductivity. This is because in the dielectric, the electric field injected from the transmission signal electrode to the communication medium propagates due to the polarization action of the dielectric.

  Specifically, a metal such as an electric wire can be used as the conductor, and pure water or the like can be used as the dielectric. However, communication is possible even with a living body having both properties, or a saline solution. In addition, since it has a dielectric constant in vacuum and air, it can communicate as a communication medium.

  Next, noise will be described. In the space, the potential fluctuates due to various factors such as noise from an AC power source, noise from fluorescent lamps, various home appliances, electrical equipment, and influence of charged fine particles in the air. Until now, these potential fluctuations have been ignored, but these noises overlap each part of the transmission device, communication medium, and reception device.

  FIG. 21 is a schematic diagram showing the communication system 100 of FIG. 1 as an equivalent circuit including a noise component. That is, the communication system 600 of FIG. 21 corresponds to the communication system 500 of FIG. 9, the transmission device 610 of the communication system 600 corresponds to the transmission device 510 of the communication system 500, and the reception device 620 corresponds to the reception device 520. The connection line 630 corresponds to the connection line 630.

  In the transmission device 610, the signal source 613-1, the reference point 613-2 in the transmission device, Cte 614, Ctg 615, the reference point 616-1, the reference point 616-2, Ctb 617-1, Cth 617-2, and Cti 617-3 are: Signal source 513-1, in-transmission device reference point 513-2, Cte 514, Ctg 515, reference point 516-1, reference point 516-2, Ctb 517-1, Cth 517-2, and Cti 517-3, respectively. Corresponding to However, unlike the case of FIG. 9, the transmission apparatus 610 includes two signal sources, noise 641 and noise 642, between Ctg 615 and reference point 616-1 and Cth 617-2 and reference point 616-2, respectively. Between.

  In the receiving device 620, Rr 623-1, detector 623-2, reference point 623-3 in the receiving device, Cre 624, Crg 625, reference point 626-1, reference point 626-2, Crb 627-1, Crh 627-2, and Cri 627. -3, Rr 523-1, detector 523-2, reference point 523-3 in the reception device, Cre 524, Crg 525, reference point 526-1, reference point 526-2, Crb 527-1, respectively. It corresponds to Crh527-2 and Cri527-3. However, unlike the case of FIG. 9, the receiving device 620 includes two signal sources, noise 644 and noise 645, between Crh 627-2 and reference point 626-2, and Crg 625 and reference point 626-1, respectively. Between.

  In connection line 630, Rm 631, Cm 632, Rm 633, and reference point 636 correspond to Rm 531, Cm 532, Rm 533, and reference point 536 of connection line 530, respectively. However, unlike the case of FIG. 9, the connection line 630 is provided with noise 643 constituted by a signal source between the Cm 532 and the reference point 536.

  Since each device operates based on the reference point 613-2 in the transmission device or the reference point 623-3 in the reception device, which is the ground potential of the device itself, noise that overlaps with the reference point 613-2 in the transmission device and the communication medium As long as the components are relatively the same with respect to the receiving device, the operation is not affected. On the other hand, particularly when the distance between the devices is large or in a noisy environment, there is a high possibility that a relative difference in noise occurs between the devices. That is, the movements of noise 641 to noise 645 are different from each other. If there is no temporal variation, this difference is not a problem as long as the relative difference in signal level to be used is transmitted, but when the noise fluctuation period overlaps the frequency band used, It is necessary to determine the frequency and signal level to be used in consideration of the noise characteristics. In other words, the communication system 600 can determine the frequency and signal level to be used while considering the noise characteristics. It also has tolerance, can eliminate the need for a physical reference point path, and can realize communication using only the communication signal transmission path, so that it is possible to provide a communication environment that is not easily restricted by the use environment.

  Next, the influence on communication due to the distance between the transmission device and the reception device will be described. As described above, according to the principle of the present invention, if a sufficient capacitance can be formed in the space between the transmission reference electrode and the reception reference electrode, a path by the ground in the vicinity between the transmission / reception device and other electrical It does not require a path and does not depend on the distance between the transmission signal electrode and the reception signal electrode. Therefore, for example, as in the communication system 700 shown in FIG. 22, the transmission device 710 and the reception device 720 are placed at a long distance, and the transmission signal electrode 711 and the reception signal are transmitted by the communication medium 730 having sufficient conductivity or dielectric properties. Communication is possible by electrostatically coupling the electrode 721. At this time, the transmission reference electrode 712 is electrostatically coupled to a space outside the transmission device 710, and the reception reference electrode 722 is electrostatically coupled to a space outside the reception device 720. Therefore, the transmission reference electrode 712 and the reception reference electrode 722 do not need to be electrostatically coupled to each other. However, as the communication medium 730 becomes longer and larger, the capacitance with respect to the space also increases. Therefore, it is necessary to consider these when determining each parameter.

  22 is a system corresponding to the communication system 100 in FIG. 1. The transmission device 710 corresponds to the transmission device 110, the reception device 720 corresponds to the reception device 120, and the communication medium 730 is a communication device. This corresponds to the medium 130.

  In the transmission device 710, the transmission signal electrode 711, the transmission reference electrode 712, and the signal source 713-1 correspond to the transmission signal electrode 111, the transmission reference electrode 112, and the transmission unit 113 (or a part thereof), respectively. Similarly, in the reception device 720, the reception signal electrode 721, the reception reference electrode 722, and the signal source 723-1 correspond to the reception signal electrode 121, the reception reference electrode 122, and the reception unit 123 (or a part thereof), respectively. To do.

  Therefore, the description about each of these parts is omitted.

  As described above, the communication system 700 eliminates the need for a physical reference point path and can realize communication using only the communication signal transmission path, so that it is possible to provide a communication environment that is not restricted by the use environment.

  In the above description, the transmission signal electrode and the reception signal electrode are described as being in non-contact with the communication medium. However, the present invention is not limited thereto, and the transmission reference electrode and the reception reference electrode are sufficient between the surrounding spaces of the respective devices. If a sufficient electrostatic capacity can be obtained, the transmission signal electrode and the reception signal electrode may be connected by a conductive communication medium.

  FIG. 23 is a schematic diagram illustrating an example of a communication system in a case where a transmission reference electrode and a reception reference electrode are connected via a communication medium.

  In FIG. 23, a communication system 740 is a system corresponding to the communication system 700 of FIG. However, in the case of the communication system 740, the transmission signal electrode 711 does not exist in the transmission device 710, and the transmission device 710 and the communication medium 730 are connected at the contact point 741. Similarly, the reception device 720 in the communication system 740 does not have the reception signal electrode 721, and the reception device 710 and the communication medium 730 are connected at the contact point 742.

  In a normal wired communication system, there are at least two signal lines, and communication is performed using a relative difference between these signal levels. However, according to the present invention, communication is performed with one signal line. It can be performed.

  That is, the communication system 740 can also provide a communication environment that is not restricted by the use environment, because a physical reference point path is unnecessary and communication can be realized only by the communication signal transmission path.

  Next, a specific application example of the communication system as described above will be described. For example, the communication system as described above can use a living body as a communication medium. FIG. 24 is a schematic diagram illustrating an example of a communication system when communication is performed via a human body. In FIG. 24, the communication system 750 transmits music data from a transmission device 760 attached to the arm of the human body, receives the music data by the reception device 770 attached to the head of the human body, and converts it into voice. This is a system for outputting and allowing the user to view. The communication system 750 is a system corresponding to the above-described communication system (for example, the communication system 100), and the transmission device 760 and the reception device 770 correspond to the transmission device 110 and the reception device 120, respectively. In the communication system 750, the human body 780 is a communication medium and corresponds to the communication medium 130 in FIG.

  That is, the transmission device 760 includes the transmission signal electrode 761, the transmission reference electrode 762, and the transmission unit 763, and corresponds to the transmission signal electrode 111, the transmission reference electrode 112, and the transmission unit 113 in FIG. The reception device 770 includes a reception signal electrode 771, a reception reference electrode 772, and a reception unit 773, and corresponds to the reception signal electrode 121, the reception reference electrode 122, and the reception unit 123 of FIG.

  Therefore, the transmission device 760 and the reception device 770 are installed so that the transmission signal electrode 761 and the reception signal electrode 771 are in contact with or close to the human body 780 that is a communication medium. Since the transmission reference electrode 762 and the reception reference electrode 772 only need to be in contact with the space, there is no need for coupling with the ground in the vicinity or coupling between the transmission / reception devices (or electrodes).

  FIG. 25 is a diagram for explaining another example for realizing the communication system 750. In FIG. 25, the receiving device 770 contacts (or approaches) the human body 780 at the sole portion, and performs communication with the transmitting device 760 attached to the arm portion of the human body 780. Also in this case, the transmission signal electrode 761 and the reception signal electrode 771 are provided so as to be in contact with (or close to) the human body 780 that is a communication medium, and the transmission reference electrode 762 and the reception reference electrode 772 are provided toward the space. ing. In particular, this is an application example that cannot be realized by the prior art in which the earth is one of the communication paths.

  That is, the communication system 750 as described above eliminates the need for a physical reference point path and can realize communication using only the communication signal transmission path, so that it is possible to provide a communication environment that is not restricted by the use environment. it can.

  In the communication system as described above, there is no particular limitation on the modulation method of the signal flowing in the communication medium as long as it can be handled by both the transmission device and the reception device. Based on the characteristics of the entire communication system, , The most suitable method can be selected. Specifically, the modulation method includes any one of a baseband, amplitude-modulated, or frequency-modulated analog signal, a baseband, amplitude-modulated, frequency-modulated, or phase-modulated digital signal, Alternatively, a plurality of mixtures may be used.

  Furthermore, in the communication system as described above, it is possible to establish a plurality of communications by using a single communication medium, and execute full-duplex communication, communication between a plurality of devices using a single communication medium, or the like. You may be able to do it.

  An example of a method for realizing such multiplex communication will be described. The first is a method of applying a spread spectrum method. In this case, a frequency bandwidth and a specific time series code are negotiated between the transmission device and the reception device. Then, the transmission apparatus changes the frequency of the original signal in accordance with the time-series code within this frequency bandwidth, spreads it over the entire frequency band, and transmits it. After receiving the spread component, the receiving device decodes the received signal by integrating the received signal.

  The effect obtained by frequency spreading will be described. According to the channel capacity theorem of Shannon and Hartley, the following equation holds.

  Here, C [bps] indicates the channel capacity, and indicates the theoretical maximum data rate that can be sent to the communication path. B [Hz] indicates the channel bandwidth. S / N indicates a signal-to-noise power ratio (SN ratio). Further, if the above equation is expanded by Macrolin and S / N is low, the above equation (23) can be approximated as the following equation (24).

  Thus, for example, if S / N is a level below the noise floor, S / N << 1, but by increasing the channel bandwidth B, the channel capacity C can be raised to a desired level.

  If the time-series code is different for each communication channel and the frequency spread behavior is different, the frequency spreads without interfering with each other and mutual interference is eliminated, so that multiple communications can be performed simultaneously. it can.

  FIG. 26 is a diagram showing another configuration example of the communication system to which the present invention is applied. In the communication system 800 shown in FIG. 26, four transmission apparatuses 810-1 to 810-4 and five reception apparatuses 820-1 to 820-5 are transmitted via a communication medium 830 using a spread spectrum method. Perform multiplex communication.

  The transmission device 810-1 corresponds to the transmission device 110 of FIG. 1, has a transmission signal electrode 811 and a transmission reference electrode 812, and further has an original signal supply unit 813, multiplication as a configuration corresponding to the transmission unit 113. 814, a spread signal supply unit 815, and an amplifier 816.

  The original signal supply unit 813 supplies the multiplier 814 with an original signal that is a signal before spreading the frequency. The spread signal supply unit 815 supplies a spread signal for spreading the frequency to the multiplier 814. As a typical spreading method using the spread signal, there are two types of methods, a direct sequence method (hereinafter referred to as DS method) and a frequency hopping method (hereinafter referred to as FH method). The DS method is a method in which the multiplier 814 multiplies the above time-series code having at least a frequency component higher than that of the original signal, places the multiplication result on a predetermined carrier wave, amplifies it in the amplifier 815, and outputs it. .

  In the FH system, the carrier wave frequency is changed by the above time-series code to obtain a spread signal, multiplied by the original signal supplied from the original signal supply unit 813 by the multiplier 814, amplified by the amplifier 815, and then output. It is a method. One output of the amplifier 815 is connected to the transmission signal electrode 811, and the other is connected to the transmission reference electrode 812.

  The transmission apparatus 810-2 to the transmission apparatus 810-4 have the same configuration, and the description of the transmission apparatus 810-1 described above can be applied.

  The receiving device 820-1 corresponds to the receiving device 120 of FIG. 1, has a reception signal electrode 821 and a reception reference electrode 822, and further, as a configuration corresponding to the reception unit 123, an amplifier 823, a multiplier 824, A spread signal supply unit 825 and an original signal output unit 826 are provided.

  The receiving device 820-1 first restores the electrical signal based on the method of the present invention, and then performs the original signal (the signal supplied by the original signal supply unit 813) by signal processing opposite to that of the transmitting device 810-1. Restore.

  A frequency spectrum by this method is shown in FIG. The horizontal axis represents frequency and the vertical axis represents energy. The spectrum 841 is a spectrum with a fixed frequency, but energy is concentrated at a specific frequency. In this method, the signal cannot be restored if the energy drops below the noise floor 843. On the other hand, a spectrum 842 shows a spectrum of a spread spectrum method, but energy is dispersed over a wide frequency band. Since the rectangular area in the figure can be considered to indicate the total energy, the signal of the spectrum 842 integrates the energy over the entire frequency band even though each frequency component is below the noise floor 843. Can restore the original signal and communication is possible.

  By performing communication using the spread spectrum system as described above, the communication system 800 can perform simultaneous communication using the same communication medium 830 as shown in FIG. In FIG. 26, paths 831 to 835 indicate communication paths on the communication medium 830. Further, by using the spread spectrum system, the communication system 800 can perform many-to-one communication as shown by the path 831 and the path 832 or many-to-many communication.

  The second is a method of applying a frequency division method in which a frequency bandwidth is determined between a transmission device and a reception device and is further divided into a plurality of regions. In this case, the transmission device (or the reception device) follows a specific frequency band allocation rule or detects a free frequency band at the start of communication, and performs frequency band allocation based on the detection result.

  FIG. 28 is a diagram showing another configuration example of a communication system to which the present invention is applied. In the communication system 850 shown in FIG. 28, four transmission apparatuses 860-1 to 860-4 and five reception apparatuses 870-1 to 870-5 are connected via a communication medium 880 using a frequency division method. Perform multiplex communication.

  The transmission device 860-1 corresponds to the transmission device 110 of FIG. 1, has a transmission signal electrode 861 and a transmission reference electrode 862, and further has an original signal supply unit 863, a multiplication as a configuration corresponding to the transmission unit 113. 864, a variable frequency source 865, and an amplifier 866.

  The oscillation signal having a specific frequency component generated by the variable frequency oscillation source 865 is multiplied by the original signal supplied from the original signal supply unit 863 by the multiplier 864, amplified by the amplifier 866, and then output. (Filtering shall be performed as appropriate). One output of the amplifier 866 is connected to the transmission signal electrode 861 and the other is connected to the transmission reference electrode 862.

  The transmission apparatuses 860-2 to 860-4 have the same configuration, and the description of the transmission apparatus 860-1 described above can be applied, and thus the description thereof is omitted.

  The receiving device 870-1 corresponds to the receiving device 120 in FIG. 1 and includes a reception signal electrode 871 and a reception reference electrode 872, and further, as a configuration corresponding to the reception unit 123, an amplifier 873, a multiplier 874, A frequency variable transmission source 875 and an original signal output unit 876 are provided.

  The receiving device 870-1 first restores the electrical signal based on the method of the present invention, and then performs the original signal (the signal supplied by the original signal supply unit 863) by signal processing opposite to that of the transmitting device 860-1. Restore.

  An example of a frequency spectrum by this method is shown in FIG. The horizontal axis represents frequency and the vertical axis represents energy. Here, for convenience of explanation, as shown in FIG. 29, an example is shown in which the entire frequency bandwidth 890 (BW) is divided into five bandwidths 891 to 895 (FW). Each frequency band divided in this way is used for communication on different communication paths. That is, the transmission device 860 (reception device 870) of the communication system 850 suppresses mutual interference as shown in FIG. 28 by using different frequency bands for each communication path, and in one communication medium 880. A plurality of communications can be performed simultaneously. In FIG. 28, paths 881 to 885 indicate communication paths on the communication medium 880. Further, by using the frequency division method, the communication system 850 can perform many-to-one communication as shown by the path 881 and the path 882 and many-to-many communication.

  Here, the communication system 850 (the transmission device 860 or the reception device 870) has been described as dividing the entire bandwidth 890 into five bandwidths 891 to 895, but the number of divisions may be any number. The bandwidths may be different from each other.

  The third is a method of applying a time division method in which the communication time is divided into a plurality of times between the transmission device and the reception device. In this case, the transmission device (or the reception device) follows a specific time division rule or detects a free time region at the start of communication, and divides the communication time based on the detection result.

  FIG. 30 is a diagram showing another configuration example of the communication system to which the present invention is applied. In the communication system 900 shown in FIG. 30, four transmission apparatuses 910-1 to 910-4 and five reception apparatuses 920-1 to 920-5 are connected via a communication medium 930 using a time division method. Perform multiplex communication.

  The transmission device 910-1 corresponds to the transmission device 110 in FIG. 1, includes a transmission signal electrode 911 and a transmission reference electrode 912, and further includes a time control unit 913, a multiplier as a configuration corresponding to the transmission unit 113. 914, a source 915, and an amplifier 916.

  The time control unit 913 outputs an original signal at a predetermined time. The multiplier 914 multiplies the original signal and the oscillation signal supplied from the oscillation source 915 and outputs the result from the amplifier 916 (filtering is performed as appropriate). One output of the amplifier 916 is connected to the transmission signal electrode 911, and the other is connected to the transmission reference electrode 912.

  The transmission apparatuses 910-2 to 910-4 have the same configuration, and the description of the transmission apparatus 910-1 described above can be applied.

  The reception device 920-1 corresponds to the reception device 120 of FIG. 1, includes a reception signal electrode 921 and a reception reference electrode 922, and further includes an amplifier 923, a multiplier 924, and a configuration corresponding to the reception unit 123. A transmission source 925 and an original signal output unit 926 are provided.

  The receiving device 920-1 first restores the electrical signal based on the method of the present invention, and then performs the original signal (original signal supplied by the time control unit 913) by signal processing reverse to that of the transmitting device 920-1. Restore.

  An example of the spectrum on the time axis according to this method is shown in FIG. The horizontal axis indicates time, and the vertical axis indicates energy. Here, for convenience of explanation, five time bands 941 to 945 are shown, but in practice, the time bands continue to be the same thereafter. Each time band divided in this way is used for communication on different communication paths. That is, the transmission apparatus 910 (reception apparatus 920) of the communication system 900 performs communication in a different time band for each communication path, thereby suppressing mutual interference as illustrated in FIG. , Multiple communications can be performed simultaneously. In FIG. 30, paths 931 to 935 represent communication paths on the communication medium 930. Further, by using the time division method, the communication system 900 can perform many-to-one communication as shown by the path 931 and the path 932 and many-to-many communication.

  Here, the time widths of the respective time zones divided by the communication system 900 (the transmission device 910 or the reception device 920) may be different from each other.

  Furthermore, as a method other than those described above, two or more of the first to third communication methods may be combined.

  The ability of a transmitting device and a receiving device to communicate with multiple other devices at the same time is particularly important in certain applications. For example, assuming application to a ticket for transportation facilities, when a user who possesses both a device A having commuter pass information and a device B having an electronic money function uses an automatic ticket gate, By using the method, communication is performed simultaneously with the devices A and B. For example, when the use section includes a section other than the commuter pass, the shortage amount is deducted from the electronic money of the apparatus B. It can be used for various purposes.

  The flow of communication processing executed in the communication between the transmission apparatus and the reception apparatus as described above, taking the case of communication between the transmission apparatus 110 and the reception apparatus 120 of the communication system 100 in FIG. This will be described with reference to a flowchart.

  The transmission unit 113 of the transmission device 110 generates a signal to be transmitted in step S1, and transmits the generated signal onto the communication medium 130 via the transmission signal electrode 111 in step S2. When the signal is transmitted, the transmission unit 113 of the transmission device ends the communication process. A signal transmitted from the transmission device 110 is supplied to the reception device 120 via the communication medium 130. The reception unit 123 of the reception device 120 receives the signal via the reception signal electrode 121 in step S21, and outputs the received signal in step S22. The receiving unit 123 that has output the received signal ends the communication process.

  As described above, the transmission device 110 and the reception device 120 do not need to construct a closed circuit using the reference electrode, and only transmit and receive signals through the signal electrode, and stable communication processing without being affected by the environment. Can be easily performed. Since the communication processing structure is simple, the communication system 100 can easily use various communication methods such as modulation, encoding, encryption, or multiplexing.

  In the communication system described above, the transmission device and the reception device are described as separate units. However, the present invention is not limited to this, and communication is performed using a transmission / reception device having the functions of both the transmission device and the reception device described above. A system may be constructed.

  FIG. 33 is a diagram showing another configuration example of a communication system to which the present invention is applied.

  In FIG. 33, the communication system 950 includes a transmission / reception device 961, a transmission / reception device 962, and a communication medium 130. The communication system 950 is a system in which the transmission / reception device 961 and the transmission / reception device 962 transmit and receive signals bidirectionally via the communication medium 130.

  The transmission / reception device 961 has both the configuration of the transmission unit 110 similar to the transmission device 110 in FIG. 1 and the reception unit 120 similar to the reception device 120. That is, the transmission / reception device 961 includes a transmission signal electrode 111, a transmission reference electrode 112, a transmission unit 113, a reception signal electrode 121, a reception reference electrode 122, and a reception unit 123.

  That is, the transmission / reception device 961 transmits a signal via the communication medium 130 using the transmission unit 110 and receives a signal supplied via the communication medium 130 using the reception unit 120. As described above, since the multiplex communication is possible in the communication method of the present invention, also in the transmission / reception device 961 in this case, the communication by the transmission unit 110 and the communication by the reception unit 120 are simultaneously performed (so as to overlap in time) ).

  The transmission / reception device 962 has the same configuration as that of the transmission / reception device 961 and operates in the same manner, and thus the description thereof is omitted. That is, the transmission / reception device 961 and the transmission / reception device 962 perform bidirectional communication via the communication medium 130 in the same manner.

  In this way, the communication system 950 (the transmission / reception device 961 and the transmission / reception device 962) can easily realize bidirectional communication that is not restricted by the usage environment.

  In the case of the transmission / reception device 961 and the transmission / reception device 962, the transmission signal electrode and the reception signal electrode are electrically connected to the communication medium as in the case of the transmission device and the reception device described with reference to FIG. Of course, the contact 741 or the contact 742 may be provided. In the above description, the transmission signal electrode 111, the transmission reference electrode 112, the reception signal electrode 121, and the reception reference electrode 122 are described as being separate from each other. The reception signal electrode 121 may be configured by one electrode, and the transmission reference electrode 112 and the reception reference electrode 122 are configured by one electrode (the transmission unit 113 and the reception unit 123 are signal electrodes or reference electrodes). May be shared).

  In the above description, each device (transmitting device, receiving device, and communication device) of the communication system to which the present invention is applied has been described so that the reference potential in each device is connected to the reference electrode. For example, a differential circuit that operates with two signals having different phases from each other may be configured. One signal of the differential circuit is connected to the signal electrode and transmitted to the communication medium, and the other of the differential circuit is Information can also be transmitted by connecting the above signal to the reference electrode.

  Next, a communication system to which the present invention is applied will be described. FIG. 34 is a diagram showing a configuration example according to an embodiment of a communication system to which the present invention is applied.

  A communication system 1000 shown in FIG. 34 is an information processing system in which a transmission device 1001 that transmits data and a reception device 1002 that receives the data communicate via a user 1003 (human body). It is a communication system that does not need to construct a closed circuit using a reference electrode, simply transmits and receives signals through the signal electrode, and easily performs stable communication processing without being affected by the environment. That is, the communication system 1000 is a communication system that performs communication by the same method as the communication system 100 of FIG.

  The communication system 1000 in FIG. 34 is installed in a predetermined facility, for example, while receiving an instruction input from the user 1003, route guidance, facility guidance, service guidance, introduction of facilities and events, explanation of exhibits, and explanation of user interface operations. This is a system for providing a service such as Of course, the content of the service provided to the user 1003 may be anything.

  For example, the receiving device 1002 is installed inside a predetermined housing, and the transmitting device 1001 is installed under the floor near the housing. A user 1003 who receives a service is located in a predetermined place (within a range in which the transmission device 1001 can transmit a signal) designated by a mark or the like near the transmission device 1001. For example, the position is clearly indicated on the floor by characters, patterns, unevenness, and the like. In addition, for example, a pedestal on which the user 1003 receiving the service is located may be provided, and the transmission device 1001 may be installed inside the pedestal. A chair or the like may be used instead of the pedestal.

  The transmission device 1001 transmits a signal to the human body of the user 1003. The user 1003 who receives the service further brings his / her body (for example, a hand or a finger) close to or in contact with the plurality of reception signal electrodes of the reception device 1002 (the reception device 1002 is positioned within a range in which the signal can be received). ). The reception device 1002 receives signals transmitted via the user 1003 at each of the plurality of reception signal electrodes, and acquires data transmitted from the transmission device 1001 from these reception signals.

  The receiving apparatus 1002 measures the signal strength of each received signal, and determines the distance from each received signal electrode of the human body of the user 1003 that is in proximity to or in contact with the received signal electrode based on the signal strength. Furthermore, based on those distances, the position of the human body of the user 1003 and the position change are specified three-dimensionally. With this function, the user 1003 can input a user instruction to the reception apparatus 1002 by controlling the distance between the reception signal electrode of the reception apparatus 1002 and the hand or finger in the vicinity of the reception signal electrode. it can.

  That is, the communication system 1000 is a communication system that performs communication between the transmission device 1001 and the reception device 1002, and is also a user interface for a user 1003 that is a medium for the communication.

  The transmission device 1001 includes a communication processing unit 1011, a transmission unit 1012, and a transmission signal electrode 1013. The transmission device 1001 is, for example, a device corresponding to the transmission device 110 in FIG. That is, the transmission unit 1012 corresponds to the transmission unit 113 in FIG. 1, and the transmission signal electrode 1013 corresponds to the transmission signal electrode 111. In FIG. 34, the transmission reference electrode that forms a pair with the transmission electrode 1013 (forms an electrode pair) corresponding to the transmission reference electrode 112 is omitted (it will be described as being connected to the ground). .

  The communication processing unit 1011 performs processing for generating data to be transmitted to the receiving device 1002 and supplying the data to the transmitting unit 1012. The transmission unit 1012 is provided between the transmission signal electrode 1011 and the ground (transmission reference electrode), and includes a signal including the data supplied from the communication processing unit 1011 between these electrodes (an electric signal to be transmitted to the reception device 1002 ( Potential difference)). The transmission signal electrode 1013 is provided toward the floor so that electrostatic coupling is stronger than the transmission reference electrode for the user 1003 located on the floor.

  The receiving device 1002 is installed in a predetermined housing (not shown), for example, and is a device corresponding to the receiving device 120 in FIG. That is, the receiving device 1002 includes four electrode pairs and a receiving unit, each corresponding to the receiving signal electrode 121, the receiving reference electrode 122, and the receiving unit 123.

  Each of the electrode pairs includes a reception signal electrode (reception signal electrode 1021-1 to reception signal electrode 1021-4) and a reception reference electrode (not shown), and each of the reception units has a resistance (resistance 1022-1). To 1022-4) and detectors (detectors 1023-1 to 1023-4). In FIG. 34, each reception reference electrode is not shown (it will be described as being connected to the ground).

  The reception signal electrodes 1021-1 to 1021-4 are arranged in an array on a plane parallel to the upper surface of the housing, and the user 1003 who is in contact with or close to these electrodes (upper surface of the housing). Electrostatic coupling to the hand or finger is stronger than the reception reference electrode.

  The resistor 1022-1 has one end connected to the reception signal electrode 1021-1 and the other end connected to the reception reference electrode. The detector 1023-1 detects an electric signal (potential difference) V1 generated at both ends of the resistor 1022-1 and outputs the value to the communication processing unit 1024.

  Similarly, the resistors 1022-2 to 1022-4 are connected between the reception signal electrode 1021-2 to the reception signal electrode 1021-4 and the reception reference electrode, respectively, and the detectors 1023-2 to 1023- 4 detects an electric signal (potential difference) (V2, V3, or V4) generated at both ends of the resistors 1022-2 to 1022-4, and outputs the value to the communication processing unit 1024.

  The communication processing unit 1024 extracts data (reception data) output from the communication processing unit 1011 of the transmission device 1001 from the electrical signals (reception signals) supplied from the detectors 1023-1 to 1023-4. At the same time, the signal strength of each received signal is measured, and the value is supplied to the position specifying unit 1025 as signal strength information. Based on the four signal intensity information supplied from the communication processing unit 1024, the position specifying unit 1025 three-dimensionally specifies the positions of the user's 1003 hand, fingers, and the like that are close to the upper part of the housing, and determines the positions. The three-dimensional position information shown is output.

  In the following description, the reception signal electrode 1021-1 to the reception signal electrode 1021-4 are referred to as the reception signal electrode 1021, and the resistance 1022-1 to the resistance 1022-4 are distinguished from each other. When it is not necessary to do this, it is referred to as a resistor 1022, and when it is not necessary to distinguish between the detectors 1023-1 to 1023-4, they are referred to as a detector 1023.

  As described above, the user 1003 who receives the service forms a position and posture in which the transmission apparatus 1001 and the reception apparatus 1002 can communicate with each other using the medium as the medium according to the installation location of the transmission apparatus 1001 and the reception apparatus 1002. The transmission signal given to the transmission signal electrode 1013 is transmitted to the reception signal electrode 1021-1 to the reception signal electrode 1021-4 via the human body (user 1003). At this time, the state of electrostatic coupling changes depending on the positional relationship (vector d1 to vector d4) between the human body (the hand or finger of the user 1003) and each of the reception signal electrodes 1021-1 to 1021-4. .

  In the communication system 1000 of FIG. 34, as described with reference to FIG. 5, parasitic capacitance exists everywhere. For example, on the receiving device 1002 side, the capacitance between the reception signal electrode 1021 and the user 1003 as a communication medium, the capacitance with respect to the space of the reception reference electrode (not shown), the reception signal electrode 1021 and the reception reference electrode (Not shown), a capacitance formed between the reception signal electrode 1021 and the space, and a user 1003 serving as a communication medium with the reception reference electrode (not shown). There is a capacitance formed between the two.

  The capacitance between the reception signal electrode 1021 and the reception reference electrode (not shown) and the user 1003 serving as a communication medium is determined by the user's 1003 hand touching or approaching the upper surface of the housing (reception signal electrode 1021). It changes depending on the relative position (distance) of the finger, the reception signal electrode 1021 and the reception reference electrode (not shown). Since the reception signal electrode 1021 and the reception reference electrode are fixed with respect to the housing, the capacitance of the user 1003 is changed by moving the hand or finger brought close to the housing in the vicinity of the upper surface thereof. To do.

  As described with reference to FIG. 9, the receiving device 1002 can extract a larger signal from the user 1003 that is a communication medium as the capacitance thereof increases. That is, the closer the position of the hand or finger of the user 1003 is to the reception signal electrode (reception reference electrode), the larger their capacitance becomes. As a result, the signals of the reception signals v1 to v4 obtained in the detector 1023. The level increases.

  The position specifying unit 1025 obtains the vectors d1 to d4 based on the signal levels of the received signals v1 to v4, and specifies the three-dimensional position of the user's hand or finger.

  By using this position information, for example, as an application to scrolling a computer screen, it makes sense to the three-dimensional movement of the human body on the electrode, and if the human body moves from top to bottom on the electrode, it scrolls down. On the other hand, it is possible to realize an interface that scrolls upward when the body electrode moves from the bottom to the top. At this time, for example, an operation of changing the scrolling speed depending on the distance between the human body and the electrode is also possible.

  In addition, since the receiving device 1002 can identify the position of the user 1003 and acquire data transmitted from the transmitting device 1001, for example, the transmitting device 1001 transmits time information as data, The instruction input meaning the original operation can be changed according to the input time.

  FIG. 35 is a block diagram showing an example of the detailed configuration inside such a receiving apparatus 1002.

  In FIG. 35, the receiving units 1031-1 to 1031-4 include a resistor 1022-1 and a detector 1023-1, a resistor 1022-2 and a detector 1023-2, a resistor 1022-3 and a detector 1023-, respectively. 3. It has a resistor 1022-4 and a detector 1023-4, and outputs reception signals v1 to v4.

  The communication processing unit 1024 includes a signal strength measurement unit 1041 and a reception data extraction unit 1042. The signal strength measurement unit 1041 measures the signal strengths of the reception signals v1 to v4 supplied from the reception units 1031-1 to 1031-4 and supplies the values to the position specification unit 1025. Further, the signal strength measurement unit 1041 supplies the reception signals v1 to v4 to the reception data extraction unit 1042.

  The reception data extraction unit 1042 extracts and outputs reception data included in these signals using all or any of the reception signals v1 to v4.

  The position specifying unit 1025 is a correspondence relationship between the position of the communication medium (the hand or finger of the user 1003) close to the reception signal electrode 1021 and the signal strength of the reception signal received by the reception units 1031-1 to 1031-4. A reference table 1051 which is table information indicating

  If the relationship between the signal intensity and distance obtained from the received signal of each received signal electrode 1021 has nonlinear characteristics due to the influence of the surrounding environment, an error may occur at a position specified by the signal intensity.

  Therefore, measure the signal strength obtained from the received signal of each electrode while moving the position of the human body by an appropriate distance interval unit (changing the position) in advance, and refer to the correspondence between each position and the signal strength. A table 1051 is generated and held in the position specifying unit 1025.

  Then, the position specifying unit 1025 refers to the reference table 1051 when actual communication is performed, extracts data in the distance range corresponding to the signal strength of each of the received signals v1 to v4, and performs linear approximation. The intermediate value can be interpolated by using the method as a measurement distance.

  In this way, the position specifying unit 1025 can easily correct the position error of the human body by referring to the reference table 1051.

  An example of the flow of reception processing executed by the reception device 1002 as described above will be described with reference to the flowchart of FIG.

  When the reception process is started, in step S1, the receiving units 1031-1 to 1031-4 each receive a signal from the hand or finger of the user 1003 that is in close proximity. In step S2, the signal strength measuring unit 1041 measures the signal strength of each received signal received by the receiving units 1031-1 to 1031-4. In step S3, the reception data extraction unit 1041 extracts reception data from the reception signal. In step S4, the position specifying unit 1025 determines the position of the user 1003 (the position of the part close to the received signal electrode 1021 of the user 1003) based on the signal strength of each received signal measured by the signal strength measuring unit 1041. Identify.

  A specific position specifying method will be described with reference to FIG.

  As shown in FIG. 37, in the orthogonal coordinate system expressed by the x-axis, y-axis, and z-axis, the reception signal electrode 1021 is arranged at each of the points a, b, and c on the xy plane, It is assumed that a human body (user 1003) exists at point p. In the following description, it is assumed that the point a is the origin and the human body (point p) is always present only in a space where the x-axis, y-axis, and z-axis are positive values.

  First, the signal intensity of the received signal is converted into the distance from each received signal electrode 1021 to point p at points a, b, and c according to the above description. The distance from point a to point p is rap, the distance from point b to point p is rbp, and the distance from point c to point p is rcp.

Next, from the obtained measurement distance, the positions of the p point on the x axis, the y axis, and the z axis are specified. This specification is realized by performing conversion from a polar coordinate system to an orthogonal coordinate system.
First, the following equations (25) and (26) are established by the cosine theorem.

  From the equations (25) and (26), the angle θax composed of the points p, a, and b and the angle θay composed of the points p, a, and c are expressed by the following equations (27) and (28). ) Can be obtained.

  Next, a perpendicular line is drawn from the point p on the xy plane, the distance from the contact point p 'to r' is rz, the distance from the point p 'to point a is rr, and a perpendicular line is drawn from the point p to the x-axis. The distance from the contact point px to the point p ′ is ry, a perpendicular line is drawn from the point p to the y-axis, the distance from the contact point py to the point p ′ is rx, the point p ′, a An angle formed by the points b and b is defined as θxy.

  From the definition of the trigonometric function, rx, ry, and θxy can be obtained by the following equations (29) and (30).

  Also, from the definition of the length of the vector, rz can be obtained by the following equation (31).

  From the above, xp, yp, and zp, which are positions on the x-axis, y-axis, and z-axis of the obtained p point, can be obtained by the following equations (32) to (34).

  As described above, the position specifying unit 1025 can specify the position of the human body of the user 1003 based on the distance from each electrode.

  Returning to FIG. 36, as described above, when the reception data is extracted and the position information of the user 1003 is generated, the reception device 1002 determines whether or not to end the reception process. Is returned to step S1, and the subsequent processing is repeated. In step S5, when it is determined that the reception process is to be ended, for example, when the power is turned off, the receiving apparatus 1002 ends the reception process.

  As described above, the communication system 1000 realizes a user interface for specifying the position of the human body in the space by using an electrostatic field, thereby allowing the user to input more diverse information more easily. Can do.

  Note that the transmitting device 1001 and the receiving device 1002 may be installed at any position other than those described above as long as they can communicate via a human body. Further, in the above description, the communication system 1000 is described as being configured by one transmission device 1001 and one reception device 1002. However, the numbers of the transmission devices 1001 and the reception devices 1002 constituting the communication system 1000 are respectively These are arbitrary and may be singular or plural.

  Further, in the above description, the receiving device 1002 has been described as having four reception signal electrodes 1021, but the number of the reception signal electrodes 1021 may be any number. Further, the arrangement position of each reception signal electrode 1021 does not have to be an array as described above, and may not be on one plane.

  FIG. 38 is a diagram illustrating another example of the arrangement of the reception signal electrodes 1021.

  In the example shown in FIG. 38, the reception signal electrode 1021-1 and the reception signal electrode 1021-3 of the reception device 1002 are arranged perpendicular to the reception signal electrode 1021-2 and the reception signal electrode 1021-4. . At this time, the housing of the receiving device 1002 also has a vertical plane parallel to the plane formed by the respective planes of the reception signal electrode 1021-1 and the reception signal electrode 1021-3 in accordance with the arrangement relationship of the reception signal electrodes 1021. , And a horizontal plane parallel to a plane formed by each plane of the reception signal electrode 1021-2 and the reception signal electrode 1021-4. That is, the operation region 1100 that is a movable range of the finger or hand of the user 1003 that can maintain a state in which the transmission device 1001 and the reception device 1002 can communicate is substantially the reception signal electrode 1021-1 and the reception signal electrode. It is limited as shown in FIG. 38 by the vertical plane formed by each plane of 1021-3 and the horizontal plane formed by each plane of the reception signal electrode 1021-2 and reception signal electrode 1021-4.

  In the case of the example of FIG. 34, four reception signal electrodes 1021 are arranged on the same plane (on the horizontal plane), and the space above the upper surface of the housing, that is, above the reception signal electrode 1021, is all the action of the human body. Although it was in the range, by arranging the reception signal electrode 1021 as shown in FIG. 38, the operation region 1100 can be limited by two planes, and false detection due to other parts of the human body approaching the electrode Can be suppressed.

  Of course, the reception signal electrode 1021 may be arranged to form three or more planes, and the operation area may be limited by the three or more planes. Further, the planes do not have to be perpendicular to each other.

  For example, as shown in FIG. 39, the plane formed by each plane of the reception signal electrode 1021-1 and the reception signal electrode 1021-3 is formed by each plane of the reception signal electrode 1021-2 and the reception signal electrode 1021-4. Each of the reception signal electrodes 1021 may be arranged so as to be horizontal with the plane to be processed. In the case of the example of FIG. 39, the reception signal electrode 1021-1 is disposed at a position facing the reception signal electrode 1021-2 so that the plane is horizontal, and the reception signal electrode 1021-3 is horizontal. It is arranged at a position facing the reception signal electrode 1021-4 so as to be.

  At this time, the housing of the reception device 1002 also has a horizontal plane parallel to the plane formed by the respective planes of the reception signal electrode 1021-1 and the reception signal electrode 1021-3 in accordance with the arrangement relationship of the reception signal electrodes 1021. A horizontal plane parallel to a plane formed by each plane of the reception signal electrode 1021-2 and the reception signal electrode 1021-4. That is, the operation region 1120 in this case is substantially the horizontal plane formed by each plane of the reception signal electrode 1021-1 and the reception signal electrode 1021-3, and the reception signal electrode 1021-2 and the reception signal electrode 1021-4. It is sandwiched between horizontal planes formed by each plane, and at least the vertical direction is limited. Of course, the direction in which the reception signal electrode 1021 facing the operation region 1120 restricts may be any two directions other than the vertical direction, such as the horizontal direction and the front-rear direction.

  FIG. 40 is a diagram illustrating still another configuration example of the communication system 1000.

  In the case of the example in FIG. 40, the transmission device 1001 is provided not inside the floor but in the same housing as the reception device 1002, and the transmission signal electrode 1013 is the reception signal electrode 1021 of the reception device 1002 as shown in FIG. Are arranged so as to form a vertical plane that further limits the space between the two opposed horizontal planes in the horizontal direction.

  At this time, the housing in which the transmission device 1001 and the reception device 1002 are built has each of the reception signal electrode 1021-1 and the reception signal electrode 1021-3 in accordance with the arrangement relationship of the reception signal electrode 1021 and the transmission signal electrode 1013. A horizontal plane parallel to the plane formed by the plane, a horizontal plane parallel to the plane formed by each plane of the reception signal electrode 1021-2 and the reception signal electrode 1021-4, and a vertical plane parallel to the plane of the transmission signal electrode 1013. Have. That is, the operation region 1130 in this case is substantially the horizontal plane formed by each plane of the reception signal electrode 1021-1 and the reception signal electrode 1021-3, and the reception signal electrode 1021-2 and the reception signal electrode 1021-4. The vertical direction is limited by the horizontal plane formed by each plane, and one horizontal direction is limited by the vertical plane formed by the plane of the transmission signal electrode 1013.

  Of course, the arrangement position of the transmission signal electrode 1013 may be other than that shown in FIG. 40, and the operation region 1130 may be restricted in any direction.

  A method of limiting the operation region by using the transmission signal electrode 1013 in addition to the reception signal electrode 1021 while bringing the transmission signal electrode 1013 closer to the reception signal electrode 1021 is shown in FIGS. 34, 38, and 39 described above. The present invention can also be applied to examples. Of course, the present invention can be applied to the arrangement of the reception signal electrode 1021 other than those examples.

  In the example shown in FIGS. 39 and 40, the group of the reception signal electrode 1021-1 and the reception electrode 1021-3 and the group of the reception electrode 1021-2 and the reception electrode 1021-4 are arranged to face each other. Therefore, even when the signal level varies due to the individual difference of the human body (user 1003), the position of the human body can be obtained by utilizing the relative difference in signal intensity of the signals obtained at the respective reception signal electrodes 1021. Can be identified more accurately.

  Furthermore, in the case of the example shown in FIG. 40, the transmission signal electrode 1013 is disposed in the vicinity of the reception signal electrode 1021. That is, in this case, the new transmission apparatus 1001 receives the reception apparatus 1002 via the transmission signal electrode 1013 and the reception signal electrode 1021 that are close to each other even when the user 1003 (communication medium) does not exist (without the human body). A signal (information) can be transmitted to.

  Therefore, in this case, the position specifying unit 1025 determines the signal strength (signal transfer characteristics) of the received signal when the user 1003 has no hand or finger in the operation region (the state in which no communication medium is present), and the operation region. The difference between the received signal strength (signal transmission characteristics) when the user 1003 has a hand or a finger (state where the communication medium exists) is determined, and the position of the communication medium is specified based on the difference. You can also.

  The series of processes described above can be executed by hardware or can be executed by software. In this case, for example, the communication processing unit 1011 of the transmission device 1001 and the communication processing unit 1024 and the position specifying unit 1025 of the reception device 1002 are each configured as a personal computer as shown in FIG. Also good.

  In FIG. 41, a CPU (Central Processing Unit) 1201 of the personal computer 1200 performs various processes according to a program stored in a ROM (Read Only Memory) 1202 or a program loaded from a storage unit 1213 into a RAM (Random Access Memory) 1203. Execute the process. The RAM 1203 also appropriately stores data necessary for the CPU 1201 to execute various processes.

  The CPU 1201, ROM 1202, and RAM 1203 are connected to each other via a bus 1204. An input / output interface 1210 is also connected to the bus 1204.

  The input / output interface 1210 includes an input unit 1211 including a keyboard and a mouse, a display including a CRT (Cathode Ray Tube) and an LCD (Liquid Crystal Display), an output unit 1212 including a speaker, a hard disk, and the like. A communication unit 1214 including a storage unit 1213 and a modem is connected. The communication unit 1214 performs communication processing via a network including the Internet.

  A drive 1215 is also connected to the input / output interface 1210 as necessary, and a removable medium 1221 such as a magnetic disk, an optical disk, a magneto-optical disk, or a semiconductor memory is appropriately attached, and a computer program read from them is loaded. It is installed in the storage unit 1213 as necessary.

  When the above-described series of processing is executed by software, a program constituting the software is installed from a network or a recording medium.

  For example, as shown in FIG. 41, this recording medium is distributed to distribute the program to the user separately from the apparatus main body, and includes a magnetic disk (including a flexible disk) on which the program is recorded, an optical disk ( Removable media 1221 made of CD-ROM (compact disk-read only memory), DVD (digital versatile disk), magneto-optical disk (including MD (mini-disk) (registered trademark)), or semiconductor memory In addition to being configured, it is configured by a ROM 1202 on which a program is recorded and a hard disk included in the storage unit 1213 and distributed to the user in a state of being incorporated in the apparatus main body in advance.

  In the present specification, the step of describing the program recorded on the recording medium is not limited to the processing performed in chronological order according to the described order, but is not necessarily performed in chronological order. It also includes processes that are executed individually.

  Further, in this specification, the system represents the entire apparatus composed of a plurality of devices (apparatuses).

  In the above description, the configuration described as one device may be divided and configured as a plurality of devices. Conversely, the configurations described above as a plurality of devices may be combined into a single device. Of course, configurations other than those described above may be added to the configuration of each device. Furthermore, if the configuration and operation of the entire system are substantially the same, a part of the configuration of a certain device may be included in the configuration of another device. That is, the embodiment of the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the gist of the present invention.

  The present invention can be applied to a communication system, for example.

It is a figure which shows the structural example which concerns on one Embodiment of the communication system to which this invention is applied. It is a figure which shows the example of the equivalent circuit of the communication system of FIG. 1 in an ideal state. FIG. 3 is a diagram illustrating an example of a calculation result of an effective value of a voltage generated at both ends of a reception load resistor in the model of FIG. 2. It is a figure which shows the example of the model of the physical structure of the communication system of FIG. It is a figure which shows the example of the model of each parameter which generate | occur | produces in the model of FIG. It is a schematic diagram which shows the example of distribution of the electric line of force with respect to an electrode. It is a schematic diagram which shows the other example of distribution of the electric line of force with respect to an electrode. It is a figure explaining the other example of the model of the electrode in a transmitter. It is a figure which shows the example of the equivalent circuit of the model of FIG. It is a figure which shows the example of the frequency characteristic of the communication system of FIG. It is a figure which shows the example of the signal received in the receiver. It is a figure which shows the example of the arrangement | positioning place of an electrode. It is a figure which shows the other example of the arrangement | positioning place of an electrode. It is a figure which shows the further another example of the arrangement | positioning location of an electrode. It is a figure which shows the further another example of the arrangement | positioning location of an electrode. It is a figure which shows the further another example of the arrangement | positioning location of an electrode. It is a figure which shows the further another example of the arrangement | positioning location of an electrode. It is a figure which shows the further another example of the arrangement | positioning location of an electrode. It is a figure which shows the structural example of an electrode. It is a figure which shows the other structural example of an electrode. It is a figure which shows the other example of the equivalent circuit of the model of FIG. It is a figure which shows the example of arrangement | positioning of the communication system of FIG. It is a figure which shows the other structural example of the communication system to which this invention is applied. It is a figure which shows the actual usage example which concerns on one Embodiment of the communication system to which this invention is applied. It is a figure which shows the other usage example which concerns on one Embodiment of the communication system to which this invention is applied. It is a figure which shows the further another structural example of the communication system to which this invention is applied. It is a figure which shows the example of distribution of a frequency spectrum. It is a figure which shows the further another structural example of the communication system to which this invention is applied. It is a figure which shows the example of distribution of a frequency spectrum. It is a figure which shows the further another structural example of the communication system to which this invention is applied. It is a figure which shows the example of the time distribution of a signal. It is a flowchart which shows the example of the flow of a communication process. It is a figure which shows the further another structural example of the communication system to which this invention is applied. It is a figure which shows the actual usage example which concerns on one Embodiment of the communication system to which this invention is applied. FIG. 35 is a block diagram illustrating a detailed configuration example of the reception device in FIG. 34. It is a flowchart explaining the example of the flow of a reception process. It is a figure explaining the calculation method of position determination of a human body. It is a figure which shows the other usage example which concerns on one Embodiment of the communication system to which this invention is applied. It is a figure which shows the further another usage example based on one Embodiment of the communication system to which this invention is applied. It is a figure which shows the further another usage example based on one Embodiment of the communication system to which this invention is applied. It is a figure which shows the structural example of the personal computer to which this invention is applied.

Explanation of symbols

  1000 communication system, 1001 transmission device, 1002 reception device, 1003 user, 1011 communication processing unit, 1012 transmission unit, 1013 transmission signal reference electrode, 1021 reception signal reference electrode, 1022 resistance, 1023 detection unit, 1024 communication processing unit, 1025 position Identification unit, 1031 reception unit, 1041 signal strength measurement unit, 1042 reception data extraction unit, 1051 reference table

Claims (13)

An information processing system comprising a transmission device, a reception device, and a communication medium,
The transmitter is
An electrode pair comprising a first electrode and a second electrode, wherein the first electrode forms a stronger electrostatic coupling with a space than the second electrode, and the second electrode A first electrode pair that forms a stronger electrostatic coupling with the first portion of the medium than the first electrode;
A transmission unit for supplying a transmission signal as a potential difference between the first electrode and the second electrode;
The receiving device is:
An electrode pair comprising a third electrode and a fourth electrode, wherein the third electrode forms a stronger electrostatic coupling with the space than the fourth electrode, and the fourth electrode is the communication A second electrode pair that forms an electrostatic coupling with a second portion of the medium stronger than the third electrode;
At least two sets of receiving units for generating a reception signal from a potential difference between the third electrode and the fourth electrode;
Signal strength measuring means for measuring the signal strength of the received signals obtained from the at least two sets of receiving units;
An information processing system comprising: position specifying means for specifying the position of the communication medium based on the signal intensity of each received signal measured by the signal intensity measuring means. The information processing system according to claim 1, wherein a signal transmitted between the transmission device and the reception device includes an information signal. In each of the first receiving unit group and the second receiving unit group that are a set of the receiving units, the fourth electrode of the first receiving unit group, and the fourth electrode of the second receiving unit group are: The information processing system according to claim 1, wherein the information processing systems are arranged so as to be perpendicular to each other. In each of the first receiving unit group and the second receiving unit group that are a set of the receiving units, the fourth electrode of the first receiving unit group, and the fourth electrode of the second receiving unit group are: The information processing system according to claim 1, wherein the information processing system is arranged so as to sandwich the communication medium. The second electrode and the fourth electrode are arranged so as to enable signal transmission even in the absence of the communication medium,
The information according to claim 1, wherein the position specifying unit specifies a position of the communication medium based on a difference between a signal transmission characteristic when the communication medium is not present and a signal transmission characteristic when the communication medium is present. Processing system. A receiving device for receiving a signal transmitted from a transmitting device,
An electrode pair comprising a first electrode and a second electrode, wherein the first electrode forms a stronger electrostatic coupling with the space than the second electrode, and the second electrode is a communication medium An electrode pair that forms an electrostatic coupling with a predetermined portion of the second electrode stronger than the second electrode;
From the potential difference between the first electrode and the second electrode, at least two sets of reception units that generate reception signals that are reception results of signals transmitted from the transmission device via the communication medium;
Signal strength measuring means for measuring the signal strength of the received signals obtained in the at least two sets of receiving units;
A receiving device comprising: position specifying means for specifying the position of the communication medium based on the signal strength of each received signal measured by the signal strength measuring means. The receiving device according to claim 6, further comprising information extracting means for extracting information transmitted from the transmitting device, which is included in received signals obtained by the at least two sets of receiving units. The at least two sets of receiving units are grouped into two groups, the second electrode of the first receiving unit group as one group and the second electrode of the second receiving unit group as the other group The receiving device according to claim 6, wherein the receiving devices are arranged so as to be perpendicular to each other. The at least two sets of receiving units are grouped into two groups, the second electrode of the first receiving unit group as one group and the second electrode of the second receiving unit group as the other group The receiving apparatus according to claim 6, wherein the receiving apparatus is arranged so as to sandwich an operation area of the communication medium. The second electrode is one electrode of an electrode pair included in the transmission device, and forms electrostatic coupling with a predetermined part of the communication medium stronger than the other electrode of the electrode pair, and the signal is Arranged in the vicinity of a signal electrode for transmitting to the communication medium;
The reception according to claim 6, wherein the position specifying unit specifies the position of the communication medium based on a difference between a signal transmission characteristic when the communication medium is not present and a signal transmission characteristic when the communication medium is present. apparatus. An electrode pair comprising a first electrode and a second electrode, wherein the first electrode forms a stronger electrostatic coupling with the space than the second electrode, and the second electrode is a communication medium An electrode pair that forms an electrostatic coupling with a predetermined portion of the second electrode stronger than the second electrode;
There are at least two sets of reception units that generate reception signals that are reception results of signals transmitted from the transmission device via the communication medium from the potential difference between the first electrode and the second electrode. And
A receiving method of a receiving device for receiving a signal transmitted from the transmitting device,
Measuring the signal strength of the received signals obtained in the at least two sets of receiving units;
A receiving method including the step of identifying the position of the communication medium based on the signal strength of each received signal measured by the processing of the signal strength measuring step. An electrode pair comprising a first electrode and a second electrode, wherein the first electrode forms a stronger electrostatic coupling with the space than the second electrode, and the second electrode is a communication medium An electrode pair that forms an electrostatic coupling with a predetermined portion of the second electrode stronger than the second electrode;
There are at least two sets of reception units that generate reception signals that are reception results of signals transmitted from the transmission device via the communication medium from the potential difference between the first electrode and the second electrode. And
In a program for processing a receiving device that receives a signal transmitted from the transmitting device,
Measuring the signal strength of the received signals obtained in the at least two sets of receiving units;
A program for causing a computer to execute a step of specifying the position of the communication medium based on the signal strength of each received signal measured by the processing of the signal strength measuring step.   A recording medium on which the program according to claim 12 is recorded.

Images