JP5721236B2 - Electromagnetic field generator and electromagnetic field generation method - Google Patents

Description

  The present invention relates to an electromagnetic field generation apparatus and an electromagnetic field generation method for generating an electromagnetic field in which frequency, phase, amplitude, waveform, and the like change dynamically.

  2. Description of the Related Art Conventionally, in the technical field of wireless communication, a wireless communication system that combines a modem, a frequency converter, a power amplifier, and an antenna is used as means for superimposing information on electromagnetic waves and radiating it into space. In recent years, DDS (Direct Digital Synthesizer), a technology that directly generates radio frequency signal waveforms, has been devised and commercialized for the purpose of so-called software radio applications. It has become possible to control the waveform.

Special table 2009-501510

  However, antennas are still used as means for converting high-frequency signals into electromagnetic waves and radiating them into space. Usually, the antenna use frequency, electromagnetic field radiation characteristics, radiation efficiency, and the like are determined by the shape of the conductor constituting the antenna element, the installation form of the feeding point, the installation position of the antenna, and the like. Therefore, the spatial radiation characteristics of this type of antenna are static in time and cannot be changed dynamically. Therefore, according to the conventional wireless communication system, it is difficult to superimpose information on the shape of the electromagnetic field distribution.

  As an antenna that can dynamically change the spatial radiation characteristic, there is an adaptive array antenna. According to the adaptive array antenna, the radiation directivity characteristic can be dynamically changed by electronic control. However, each antenna element of the adaptive array antenna is designed to be used in a specific frequency band, and has a specific spatial radiation characteristic. For this reason, the electromagnetic field radiation characteristics of each antenna element of the adaptive array antenna are fixed. Therefore, it is impossible to dynamically change the frequency characteristics or generate an arbitrary electromagnetic field radiation shape. Some antenna elements of adaptive array antennas can be used by switching a plurality of preset spatial radiation characteristics, and others can be used simultaneously for multiple frequency bands. It cannot be changed to. Therefore, it is difficult to superimpose information on the shape of the electromagnetic field distribution even with an adaptive array antenna.

  In addition, as a technique for efficiently radiating electromagnetic waves into space, there is a technique disclosed in Patent Document 1 (Japanese Patent Publication No. 2009-501510). FIG. 11 shows an example of a device configuration based on the technology. The technology uses a resonance phenomenon to transmit power wirelessly. That is, in this technique, two resonance devices 12 and 13 arranged with a space therebetween are used to resonate one resonance device 12 with respect to the high-frequency AC power generated by the power supply device 11, and this resonance device. By resonating the other resonance device 13 that is efficiently coupled to the device 12, energy is wirelessly transmitted to the load 14 through the space. However, according to this technique, the shape of the electromagnetic field distribution in the space that is the transmission path cannot be dynamically controlled, and the spatial radiation characteristics cannot be arbitrarily changed. Therefore, even with the technique of Patent Document 1, information cannot be superimposed on the shape of the electromagnetic field distribution.

  The present invention has been made in view of the above circumstances, and provides an electromagnetic field generation apparatus and an electromagnetic field generation method capable of generating an electromagnetic field distribution of an arbitrary shape and realizing an arbitrary spatial radiation characteristic. With the goal.

  The present invention has been made in order to solve the above-described problems. The main feature of the present invention is that a plurality of electromagnetic field radiating portions having a sufficiently small size compared to the wavelength of the generated AC electromagnetic field. And by generating an electric field or magnetic field from each electromagnetic field radiation unit according to the dynamic control of the control unit, as a result of superposition of the electromagnetic fields radiated by each electromagnetic field radiation unit, electromagnetic waves of any shape An electromagnetic field having a field distribution is generated. Further, another main feature of the present invention is that a resonance state is forcibly formed by connecting a resonance part to each electromagnetic field radiation part, and high frequency energy is temporarily stored in the resonance part so that each electromagnetic field radiation is generated. The power efficiency is improved by supplying to the part.

  The present invention also includes, for example, arranging a plurality of electric field sources or magnetic field sources having a minute size (for example, a size smaller than 1/8 of the wavelength of the radiated electromagnetic wave) as the electromagnetic field radiating unit. An arbitrary electromagnetic field is generated as a result of superposition of the electromagnetic fields radiated from.

  The operation of the present invention will be described below by taking as an example the case where a minute magnetic field is generated by a minute size magnetic field source (current source). A general antenna enters a resonance state when a radio frequency alternating current is fed to a conductor forming the antenna element, and a standing wave is placed on the conductor. In the present invention, for example, each of the plurality of electromagnetic wave radiation portions is configured by a micro-sized element (micro element), and a current equivalent to a standing wave generated in the antenna element of the general antenna described above flows to each micro element. It is formed by current superposition. Thereby, the desired electromagnetic wave similar to a general antenna is generated.

  Moreover, in this invention, the above-mentioned microelement is arranged on a two-dimensional plane as an electromagnetic wave radiation | emission part, for example. As a result, directivity control, polarization plane control, and the like realized by changing the structural shape in the existing planar antenna can be realized without changing the structural shape. In addition, according to the present invention, for example, an arbitrary current distribution can be formed by changing the amplitude, phase, and direction of the current source that feeds the microelements in a programmable manner, and various antenna characteristics can be realized. Thus, a wireless transmission antenna having programmable antenna characteristics can be realized. Further, according to the present invention, for example, a conventional wireless transmitter itself is replaced with the electromagnetic field generator according to the present invention by controlling a current source that supplies power to a microelement in accordance with an information signal to be wirelessly transmitted. Will also be possible.

The present invention having the above-described features is expressed as follows.
That is, in order to solve the above-described problem, an electromagnetic field generation device according to an aspect of the present invention includes a plurality of signal generation units that generate high-frequency signals and a high-frequency signal generated by each of the plurality of signal generation units. A plurality of electromagnetic field radiating portions radiating to space as a field, and an electromagnetic field distribution having a geometric shape in which the electromagnetic fields radiated from the plurality of electromagnetic field radiating portions are modulated in the space according to an input information signal And a configuration of an electromagnetic field generation device including a control unit that controls the plurality of signal generation units.

  In the configuration of the electromagnetic field generation device, for example, a plurality of resonances that resonate with a high-frequency signal generated by each of the plurality of signal generation units between the plurality of signal generation units and the plurality of electromagnetic field emission units. It has the part.

  In the configuration of the electromagnetic field generation device, for example, the plurality of electromagnetic field radiating units have a size smaller than the wavelength of the electromagnetic field that each radiates, and are arranged at an interval narrower than the wavelength of the electromagnetic field that each radiates. It is characterized by that.

  In the configuration of the electromagnetic field generation device, for example, each size of the plurality of electromagnetic field radiation units is 1/8 or less of the smallest wavelength of the electromagnetic field to be radiated, and the plurality of electromagnetic field radiation units The number of is 4 or more.

  In the configuration of the electromagnetic field generation device, for example, the Q value of each of the plurality of resonance units is 10 or more.

  In the configuration of the electromagnetic field generation device, for example, the control unit may be one or more of the frequency, amplitude, phase, and waveform of the high-frequency signal generated by the plurality of signal generation units according to an input information signal. The geometric shape of the electromagnetic field distribution is modulated by changing the resonance frequency of the plurality of resonance portions.

  In the configuration of the electromagnetic field generator, for example, the geometric shape of the electromagnetic field distribution is a geometric shape of an equiphase wavefront in the electromagnetic field distribution.

  In the configuration of the electromagnetic field generation device, for example, the plurality of electromagnetic field radiation units are arranged in any one of a one-dimensional shape, a two-dimensional shape, and a three-dimensional shape.

In order to solve the above problems, an electromagnetic field generation method according to an aspect of the present invention includes a step of generating a high-frequency signal by a plurality of signal generation units, and an electromagnetic field generated by each of the plurality of signal generation units. Radiating into a space from a plurality of electromagnetic field radiating portions, and an electromagnetic field distribution having a geometric shape in which the electromagnetic fields radiated from the plurality of electromagnetic field radiating portions are modulated according to an input information signal in the space. Forming a method of generating an electromagnetic field including a step of controlling the plurality of signal generators by a controller.

  According to the present invention, it is possible to generate an electromagnetic field distribution having an arbitrary shape that cannot be realized by a conventional antenna, and to realize an arbitrary spatial radiation characteristic. Therefore, for example, it is possible to obtain radiation directivity characteristics that are difficult to realize with a conventional antenna, and to generate an electromagnetic wave in which the shape of an equiphase wavefront is modulated by transmission information.

It is a figure which shows an example of a structure of the electromagnetic field generator which concerns on 1st Embodiment of this invention. It is a figure which shows typically an example of a structure of the electromagnetic field energy emission part with which the electromagnetic field generator which concerns on 1st Embodiment of this invention is provided, (a) shows the arrangement | positioning relationship of an electromagnetic field energy emission part, (b ) Is a diagram showing an example of a detailed configuration of an electromagnetic energy radiating unit. It is explanatory drawing for demonstrating the characteristic of the dipole antenna by the prior art referred in 1st Embodiment of this invention, (a) shows current distribution, (b) shows radiation | emission directivity (directivity gain). FIG. It is a figure for demonstrating the example of the characteristic of the electromagnetic field radiation | emission part with which the electromagnetic field generator which concerns on 1st Embodiment of this invention is equipped, (a) shows an example of the current pattern equivalent to the current distribution of a dipole antenna. (B) is a figure which shows an example of the pattern of the electromagnetic field intensity corresponded to the radiation | emission directivity characteristic (directivity gain) of a dipole antenna. It is a figure which shows the example of the equiphase wavefront of the electromagnetic field distribution which the electromagnetic field generated by the electromagnetic field generator which concerns on 1st Embodiment of this invention forms, (a) is a 1st example of an equipotential wavefront. (B) is a figure which shows the 2nd example of an equiphase wave front. It is a figure which shows an example of the arrangement | sequence of the electromagnetic field radiation | emission part with which the electromagnetic field generator which concerns on 2nd Embodiment of this invention is provided, and is a figure which shows the example which arranged the several electromagnetic field radiation | emission part in two dimensions. It is a figure which shows an example of the electromagnetic field distribution (electric field strength distribution) which the electromagnetic field generator which concerns on 2nd Embodiment of this invention forms, (a) shows the example of a substantially circular electromagnetic field distribution, (b ) Is a diagram showing an example of a substantially quadrangular electromagnetic field distribution. It is a figure for demonstrating an example of the structure (micro length line type | mold) of the electromagnetic field generator which concerns on 4th Embodiment of this invention. It is a figure for demonstrating an example of the structure (micro parallel plate type) of the electromagnetic field generator which concerns on 5th Embodiment of this invention. It is a figure for supplementarily explaining an example of composition of a resonance part with which an electromagnetic field generator concerning an embodiment of the present invention is provided. It is a figure for demonstrating a prior art.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
In addition, the same code | symbol represents the same element over all embodiment and all the drawings demonstrated below.

(First embodiment)
[Description of configuration]
FIG. 1 is a diagram illustrating an example of a configuration of an electromagnetic field generation device 100 according to the first embodiment of the present invention. As shown in the figure, the electromagnetic field generator 100 includes an information input terminal 110, an oscillation controller 120, and a plurality of signal generators 130-1, 130-2, 130-3,. m (m is a natural number), a plurality of resonating parts 140-1, 140-2, 140-3,..., 140-m, and a plurality of electromagnetic field energy radiating parts 150-1, 150-2, 150-3, ..., 150-m. These components are the “control unit”, “plurality of signal generation units”, “plurality of resonance units”, “plurality of electromagnetic field emission units” which are the components of the present invention described in the claims of the present application. It corresponds to each.

  In the following description, the plurality of signal generators 130-1, 130-2, 130-3,..., 130-m will be collectively referred to as the signal generator 130, and the plurality of resonators 140-1, 140-2, 140- 3,..., 140-m are collectively referred to as the resonance unit 140, and the plurality of electromagnetic field energy radiating units 150-1, 150-2, 150-3,.

  In the configuration shown in FIG. 1, the information input terminal 110 is connected to the input unit of the oscillation control unit 120, and the input unit of the signal generation unit 130 is connected to the output unit of the oscillation control unit 120. A resonating unit 140 is provided between the signal generating unit 130 and the electromagnetic energy radiating unit 150. In other words, the input unit of the resonance unit 140 is connected to the output unit of the signal generation unit 130, and the feed point of the electromagnetic energy radiating unit 150 is connected to the output unit of the resonance unit 140 via a feed line (no symbol). It is connected.

  FIG. 2 is a diagram schematically illustrating an example of the configuration of the electromagnetic field energy radiating unit 150, and (a) illustrates the electromagnetic field energy radiating units 150-1, 150-2, 150-3,. An arrangement example is shown, and (b) shows an example of the detailed configuration of each of the electromagnetic energy radiating units 150-1, 150-2, 150-3, ..., 150-m shown in (a).

  In this embodiment, as shown in FIG. 2A, each of the electromagnetic field radiating portions 150-1, 150-2, 150-3,..., 150-m is based on the wavelength λ of the electromagnetic field radiated from each. Also, each conductor is arranged in a one-dimensional (straight) manner with a spacing G smaller than the wavelength λ of the electromagnetic field radiated by each conductor. Further, as shown in FIG. 2B, each conductor of the electromagnetic wave energy radiating portions 150-1, 150-2, 150-3,..., 150-m has two conductor portions of a conductor portion 150a and a conductor portion 150b. It is composed of Feed lines (not indicated) are respectively connected to adjacent ends of the conductor parts 150a and 150b, and high-frequency currents having opposite phases are supplied from the resonance part 140 to the conductor parts 150a and 150b via the feed lines. The

  As can be understood from FIG. 2, when the wavelength λ is constant, the length L of each conductor increases as the number of electromagnetic field energy radiating portions 150-1,. Are set to be small, and each of the electromagnetic field energy radiating portions 150-1, 150-2, 150-3,..., 150-m is a micro-sized element (micro element). As described above, if the length L of each conductor is made sufficiently small and each of the electromagnetic field energy radiation portions 150-1, 150-2, 150-3,. It becomes possible to precisely control the geometric shape of the electromagnetic field distribution. From the viewpoint of controlling the geometric shape of the electromagnetic field distribution, the length L of each conductor of the electromagnetic field energy radiation portions 150-1, 150-2, 150-3,. It is desirable to set as small as possible.

  However, it is not limited to the above-mentioned example, The length L of each conductor of the electromagnetic field energy radiation | emission part 150-1,150-2,150-3, ..., 150-m depends on the use of the electromagnetic field generator 100. Can be set arbitrarily. Moreover, in the above-mentioned example, although the length L of each conductor of the electromagnetic field energy radiation | emission part 150-1,150-2,150-3, ..., 150-m was equalized, the electromagnetic field radiation | emission part 150-1 , 150-2, 150-3,..., 150-m may have different lengths. Moreover, as long as an electromagnetic field can be radiated | emitted to space, you may comprise each of electromagnetic wave energy radiation | emission part 150-1,150-2,150-3, ..., 150-m how.

  In this embodiment, each of the plurality of electromagnetic energy radiating portions 150-1, 150-2, 150-3,..., 150-m has a configuration similar to a dipole antenna. This is essentially different from a dipole antenna in that the sum of the lengths of 150a and conductor 150b is not limited to ½ of the wavelength λ. In other words, each of the plurality of electromagnetic field energy radiating units 150-1, 150-2, 150-3,..., 150-m does not necessarily resonate at the transmission frequency.

Next, an outline of the operation of the electromagnetic field generator 100 according to the present embodiment will be described.
The information input terminal 110 receives an input information signal S including information to be transmitted and passes it to the oscillation control unit 120. The oscillation control device 120 includes a plurality of signal generators 130-1, 130-2, 130-3,..., 130-m and a plurality of resonators based on the input information signal S passed from the information input terminal 110. 140-1, 140-2, 140-3, ..., 140-m are controlled. That is, based on the input information signal S, the oscillation control unit 120 determines a high-frequency signal that each of the signal generation units 130-1, 130-2, 130-3,.

  In the present embodiment, as will be described later, the oscillation control device 120 is radiated from the electromagnetic field radiation units 150-1, 150-2, 150-3,..., 150-m according to the input information signal S, respectively. For example, the frequency of the high-frequency signal generated by each of the signal generators 130-1, 130-2, 130-3,..., 130-m so that the electromagnetic field forms an electromagnetic field distribution having a desired geometric shape in space. Determine the phase, amplitude, and waveform.

  The geometric shape of the electromagnetic field distribution formed by the electromagnetic fields radiated from the electromagnetic field radiation portions 150-1, 150-2, 150-3,..., 150-m is, for example, the electromagnetic field radiation portions 150-1, 150. When viewing −2, 150-3,..., 150-m as one antenna, the radiation pattern of this antenna (for example, a pattern corresponding to the pattern of the directivity gain of a dipole antenna), the equiphase wavefront in the electromagnetic field distribution Or the like.

  The signal generators 130-1, 130-2, 130-3,..., 130-m generate high-frequency signals determined by the oscillation controller 120 under the control of the oscillation controller 120. In this embodiment, each of the signal generators 130-1, 130-2, 130-3,..., 130-m includes an oscillator for generating a high-frequency signal, but also has a function as a synthesizer. Thereby, each of the electromagnetic energy radiating parts 150-1, 150-2, 150-3,..., 150-m has an arbitrary frequency required to form an electromagnetic field distribution having a desired geometric shape. The high-frequency signal having the phase, amplitude, and waveform can be generated.

  The resonating units 140-1, 140-2, 140-3,..., 140-m are controlled by the oscillation control unit 120 to generate signal generators 130-1, 130-2, 130-3,. Each of m resonates with the high-frequency signal generated. Thereby, the resonating parts 140-1, 140-2, 140-3,..., 140-m temporarily store high-frequency energy and electromagnetic field energy radiating parts 150-1, 150-2, 150-3,. , 150-m. As described above, in the present embodiment, the sizes of the plurality of electromagnetic field energy radiation units 150-1, 150-2, 150-3,..., 150-m are set to the wavelength λ of the AC electromagnetic field generated by each. Compared to a sufficiently small size. For this reason, the plurality of electromagnetic field energy radiating units 150-1, 150-2, 150-3,..., 150-m do not resonate with the transmission frequency, and the power efficiency decreases.

  In order to improve the above-described power efficiency, in the present embodiment, a plurality of resonance units 140-1 and 140 with respect to the plurality of electromagnetic energy radiating units 150-1, 150-2, 150-3,. -2, 140-3, ..., 140-m are arranged. The oscillation control unit 120 sets the resonance frequencies of the resonance units 140-1, 140-2, 140-3,..., 140-m to appropriate values, so that these resonance units 140-1,. A resonance state is forcibly created by m. Thereby, the radiation of the electromagnetic energy radiation devices 150-1, 150-2, 150-3,..., 150-m connected to the resonating units 140-1, 140-2, 140-3,. Increase efficiency and improve power efficiency.

  The electromagnetic field energy radiating units 150-1, 150-2, 150-3,..., 150-m are high frequency energy supplied from the resonating units 140-1, 140-2, 140-3,. Is converted into electromagnetic waves and emitted. Thereby, the high frequency signals generated by the signal generators 130-1, 130-2, 130-3,..., 130-m are converted into electromagnetic field energy radiating units 150-1, 150-2, 150-3, ..., radiated from 150-m to space as an electromagnetic field.

  In the above description, the main features of this embodiment are summarized in the following two points. First, each of the plurality of minute-sized electromagnetic field energy radiating portions 150-1, 150-2, 150-3,..., 150-m generates an electric field or a magnetic field in a minute-sized space. An electromagnetic field radiation pattern is generated flexibly and dynamically by superimposing a large number of electric or magnetic fields, and an electromagnetic field distribution having a desired geometric shape is formed. Second, the electromagnetic field energy radiating units 150-1, 150-2, 150 based on the high-frequency signals generated by the signal generating units 130-1, 130-2, 130-3,..., 130-m. -3,..., 150-m are provided with resonating portions 140-1, 140-2, 140-3,..., 140-m so that power efficiency is improved when radiating electromagnetic field energy to the space. It is.

  In this embodiment, the resonance units 140-1, 140-2, 140-3,..., 140-m are provided to improve the power efficiency. In applications where it is sufficient to form a geometric electromagnetic field distribution, the resonating units 140-1, 140-2, 140-3,..., 140-m may be omitted.

[Description of operation]
Next, regarding the operation of the electromagnetic field generation apparatus 100, the electromagnetic fields radiated from the electromagnetic field energy radiation units 150-1, 150-2, 150-3,..., 150-m respectively have a desired geometric shape. The operation for forming the distribution will be described in detail.
Here, first, as a first operation example, a case where an electromagnetic field distribution is formed so as to reproduce a radiation pattern of a half-wavelength dipole antenna, which is one of the simplest antennas in various antennas, will be described. After that, as a second operation example, a case where an electromagnetic field distribution having a desired geometric shape that cannot be realized by an existing antenna device will be described.

[First operation example]
First, the characteristics of a half-wave dipole antenna used in a wireless transmitter according to the prior art will be described with reference.
3A and 3B are explanatory diagrams for explaining the characteristics of a general half-wave dipole antenna according to the prior art. FIG. 3A shows a current distribution (standing wave) 3 of the half-wave dipole antenna, and FIG. The radiation pattern 4 of the radiation directivity characteristic (directivity gain) of a half-wavelength dipole antenna is shown.

  As shown in FIG. 3A, a current source 2 is connected to the central portion of the conductor 1 of the half-wave dipole antenna. The total length of the conductor 1 is set to ½ of the wavelength of the radio frequency signal generated by the current source 2. As a result, the dipole antenna made of the conductor 1 resonates at the radio frequency generated by the current source 2, and a current distribution 3 is formed on the conductor 1 as shown in FIG. When the dipole antenna is in the resonance state in this way, the power efficiency when electromagnetic waves are radiated from the dipole antenna to the space becomes maximum, and the wireless transmitter can efficiently radiate the electromagnetic waves to the space. Further, in such a resonance state, the radiation directivity characteristic of the dipole antenna is, as shown in FIG. 3 (b), an 8-shaped radiation pattern having a node at the connection point (feeding point) of the current source 2. 4 is presented.

Based on the characteristics of the half-wave dipole antenna described above, a first operation example will be described with reference to FIG. 4 in addition to FIGS.
FIG. 4 is a diagram for explaining an example of the characteristics of the electromagnetic field energy radiating unit 150 included in the electromagnetic field generation apparatus 100. FIG. 4A shows a pattern 30 corresponding to the current distribution of the dipole antenna, and FIG. Indicates a pattern 160 of electromagnetic field intensity corresponding to the radiation directivity characteristic (transmission antenna directivity gain) of the dipole antenna. Here, the pattern 160 in FIG. 6B schematically shows the result of the electromagnetic field analysis performed by setting the current excitation amplitude of the electromagnetic energy radiating unit 150 to the current distribution pattern 30 in FIG. It is shown.

  The example shown in FIG. 4 corresponds to the case where the number of the plurality of electromagnetic field energy radiating portions 150-1, 150-2, 150-3,. That is, this corresponds to the case where m is 8. In this embodiment, the electromagnetic energy radiating units 150-1, 150-2, 150-3,..., 150-8 are one-dimensionally arranged in a half-wavelength (λ / 2) section in the radio frequency (transmission frequency). Evenly arranged. 4, the information input terminal 110, the oscillation control unit 120, the signal generation unit 130, the resonance unit 140, and the like illustrated in FIG. 1 are omitted. Here, assuming the radiation pattern of the half-wave dipole antenna, according to the Nyquist sampling theorem, the electromagnetic field energy radiation units 150-1, 150-2, 150-3 in the configuration of FIG. ,..., 150-m need only be 1/8 or less of the smallest wavelength of the electromagnetic field to be radiated, and the plurality of electromagnetic energy radiating units 150-1, 150-2, 150. The number of -3, ..., 150-m (that is, the value of m) may be 4 or more.

  Here, the half-wave dipole antenna has a configuration in which a balanced feed line is connected to two elements each having a quarter wavelength. Therefore, in order to reproduce the operation of one element of the half-wave dipole antenna, the length of one element must be divided into two or more sections according to the above-described Nyquist sampling principle. That is, in order to reproduce the operation of one element of the half-wave dipole antenna, the length of each section when one element is divided is 1/8 wavelength or less. From this, each length L of the eight electromagnetic energy radiating units 150-1,..., 150-8 shown in FIG. 4A is 1 of the wavelength λ in the radio frequency (transmission frequency) of the signal to be transmitted. / 8 or less.

  In the present embodiment, regarding the above-described conditions for reproducing the characteristics of the half-wave dipole antenna, the length L of each of the electromagnetic energy radiating units 150-1,..., 150-8 is 1/8 or less of the wavelength λ. Is set in advance, and is sufficiently small with respect to the wavelength λ. That is, each of the electromagnetic field energy radiating units 150-1,..., 150-8 is configured as a microelement. Therefore, it is not necessary to change the physical length L of each of the electromagnetic field energy radiating units 150-1,..., 150-8, and the above-described conditions necessary for reproducing the characteristics of the half-wave dipole antenna Is satisfied. In other words, according to this embodiment, the characteristics of the dipole antenna that transmits an arbitrary radio frequency having a half wavelength longer than eight times the length L of each of the electromagnetic field energy radiating units 150-1, ..., 150-8. Can be reproduced.

  According to experiments, in order to obtain a Q value equivalent to that of a dipole antenna, the Q in the resonating units 140-1,..., 140-8 connected to the electromagnetic field energy radiating units 150-1,. It is desirable to set the value to a large value of 10 or more.

As described above, the description of the first operation example will be continued assuming that the conditions for reproducing the characteristics of the half-wave dipole antenna are satisfied.
As shown in FIG. 4 (a), a plurality of electromagnetic energy radiating units 150-1, ..., 150-8 arranged in a one-dimensional manner generate current distributions 30-1, ..., 30-8, respectively. To do. When these current distributions 30-1,..., 30-8 are superimposed, a current distribution pattern 30 shown by a dotted line in FIG.

  Here, the current distributions 30-1,..., 30-8 indicate that the oscillation control unit 120 has signal generation units 130-1,..., 130- corresponding to the electromagnetic field energy radiating units 150-1,. 8 and the resonating units 140-1,..., 140-8 are determined. That is, in the present embodiment, the oscillation control unit 120 generates one of the frequencies, amplitudes, phases, and waveforms of the high-frequency signals that are generated by the signal generation units 130-1,. Or by changing each resonance frequency of the resonance parts 140-1, ..., 140-8 to 2 or more, the current distributions 30-1, ..., 150-8 generated by the electromagnetic field energy emission parts 150-1, ..., 150-8, respectively. ..., 30-8 are adjusted, and the current distribution 30 obtained by superimposing these is controlled. Thereby, the oscillation control unit 120 modulates the geometric shape of the electromagnetic field distribution of the electromagnetic field radiated from the electromagnetic field energy radiating units 150-1,..., 150-8 according to the input information signal S.

  In the present embodiment, the oscillation control unit 120 has a current distribution pattern 30 obtained by superimposing the current distributions 30-1,..., 30-8, so that the current of the half-wave dipole antenna shown in FIG. The current distributions 30-1,..., 30-8 are adjusted to be equivalent to the distribution 3.

  When the pattern 30 equivalent to the current distribution 3 of the half-wave dipole antenna is obtained, when the electromagnetic field energy radiating portions 150-1,..., 150-8 are viewed as one antenna, as shown in FIG. An electromagnetic field intensity pattern 160 equivalent to the electromagnetic field intensity pattern of the dipole antenna is obtained. That is, a radiation pattern similar to that of a dipole antenna in a conventional wireless transmitter can be reproduced.

  According to the conventional half-wave dipole antenna, the current distribution that can be generated is basically limited to the current distribution (standing wave) 3 shown in FIG. 3A and some other higher-order modes. It is done. For this reason, the radiation pattern is also limited. On the other hand, according to the electromagnetic field generation apparatus 100 according to the present embodiment, by changing the pattern of the electromagnetic field generated by the electromagnetic field energy radiating unit 150, the radiation of various antennas is not limited to a half-wave dipole antenna. The pattern can be reproduced. Therefore, for example, a mode that operates with electromagnetic waves of other frequencies and a high gain operation corresponding to an array antenna can be realized.

[Second operation example]
Next, in the second operation example, the operation in the case of forming an electromagnetic field distribution having a desired geometric shape that cannot be realized by the conventional antenna will be described with reference to FIGS. To do. Here, the geometric shape of the electromagnetic field distribution is assumed to be a geometric shape of an equiphase wavefront (wavefront having the same phase of the electromagnetic wave) in the electromagnetic field distribution.

  FIG. 5 is a diagram illustrating an example of the shape of an equiphase wavefront of the electromagnetic field distribution generated by the electromagnetic field generator 100, and FIG. 5A is a first example of an equiphase wavefront (a wavefront describing a gentle arc). (B) shows a second example of an equiphase wavefront (uneven wavefront).

  As described above, according to the electromagnetic field generator 100, by controlling the pattern of each electromagnetic field radiated from the electromagnetic field energy radiating unit 150, an arbitrary electromagnetic field distribution can be obtained as a result of the superposition. it can. Therefore, according to the electromagnetic field generator 100, the equiphase wavefront of the electromagnetic field distribution can be arbitrarily controlled by controlling the pattern of each electromagnetic field radiated from the electromagnetic field energy radiating unit 150.

  The example shown in FIG. 5A is emitted from the electromagnetic field energy radiation unit 150 so that the equiphase wavefronts 171 and 172 in the electromagnetic field distribution obtained as a result of the above-described superposition draw a concentric and gentle arc. An example of controlling each electromagnetic field pattern is shown. In this example, the oscillation control unit 120 controls the electromagnetic field patterns radiated from the plurality of electromagnetic field energy radiation units 150-1,..., 150-m shown in FIG. And the equiphase wavefront 172 are controlled (for example, a spatial interval or a temporal interval). Therefore, if the interval between the equiphase wavefront 171 and the equiphase wavefront 172 is modulated in accordance with the input information, the information can be wirelessly transmitted with the information superimposed on the equiphase wavefront.

  In the example shown in FIG. 5B, irregularities (valleys / mountains) are formed on the patterns of the equiphase wavefronts 173 and 174 in the electromagnetic field distribution obtained as a result of the above-described superposition. Also in this example, by controlling the pattern of each electromagnetic field radiated from the electromagnetic field energy radiating unit 150, uneven phase-shaped equiphase wavefronts 173 and 174 are obtained as a result of the superposition. Therefore, for example, if the number of irregularities of the equiphase wavefronts 173 and 174 is modulated in accordance with the input information signal S, information can be wirelessly transmitted by superimposing information on such equiphase wavefronts. In addition, you may combine the equiphase wavefront which has the shape which draws a gentle arc shown to Fig.5 (a), and the equiphase wavefront which has the uneven | corrugated shape shown in FIG.5 (b).

  An apparatus for detecting information superimposed on an equiphase wavefront of an electromagnetic field distribution as described above, that is, a detection apparatus for detecting a small-sized electric field or magnetic field on the receiver side, similar to the above-described electromagnetic field generation apparatus 100 Are arranged, and the arrival times of signals due to the electric field or magnetic field detected by each detection device, that is, the phases are collected to recognize the shape of the equiphase wavefront. Thereby, it is possible to perform wireless communication by superimposing information on the equiphase wavefront of the electromagnetic field. Thus, by modulating the equiphase wavefront, it becomes possible to transmit a plurality of information simultaneously.

(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIGS.
The electromagnetic field generator according to the present embodiment replaces the plurality of electromagnetic field energy radiating units 150 arranged in a one-dimensional manner with the above-described first embodiment, and includes a plurality of two-dimensional (planar) arranged in a two-dimensional manner. An electromagnetic field energy radiating unit is provided. Other configurations are the same as those of the first embodiment.

  FIG. 6 shows an arrangement of a plurality of electromagnetic energy radiating units 150x-11,..., 150x-nm, 150y-11,..., 150y-nm (n and m are natural numbers) provided in the electromagnetic field generator according to the present embodiment. It is a figure which shows an example, and shows the example which arranged these some electromagnetic field energy radiation | emission parts in two dimensions. In the figure, configurations corresponding to the information input terminal 110, the oscillation control unit 120, the signal generation unit 130, and the resonance unit 140 in the first embodiment are omitted.

  Here, as shown in FIG. 6, the electromagnetic energy radiating portions 150x-11,..., 150x-nm that generate an electric field or a magnetic field parallel to the x-axis direction are arranged in an n × m matrix. In addition, the electromagnetic field radiation portions 150y-11,..., 150y-nm that generate an electric field or a magnetic field parallel to the y-axis direction orthogonal to the x-axis direction are also arranged in an n × m matrix. That is, in the present embodiment, one electromagnetic field energy radiating portion in the x direction and one electromagnetic field energy radiating portion in the y direction are paired, and a plurality of pairs of electromagnetic field energy radiating portions are arranged in a grid. Therefore, according to the present embodiment, it is possible to form various electromagnetic field distributions having more complicated geometric shapes than in the first embodiment, and to obtain more various spatial radiation characteristics. .

FIG. 7 is a diagram illustrating an example of an electric field strength distribution (electromagnetic field distribution) formed by the electromagnetic field generator according to the present embodiment. Here, FIG. 7A shows an example of an electric field strength distribution having a substantially circular geometric shape, and FIG. 7B shows an example of an electric field strength distribution having a substantially rectangular geometric shape.
According to the electromagnetic field generator according to the present embodiment, as shown in FIG. 7, a plurality of electromagnetic field energy radiating portions 150x-11, 150x-nm, 150y-11, 150y-nm arranged in a grid. As a result of the superposition of the electromagnetic fields radiated from each, a two-dimensional electromagnetic field distribution can be formed in the vicinity of the two-dimensional plane in which these electromagnetic energy radiating portions are arranged. A geometric figure can be expressed. The example of FIG. 7 shows an example of a substantially circular electric field strength distribution and an example of a substantially quadrangular electric field strength distribution. However, according to the electromagnetic field generator according to the present embodiment, an electromagnetic field having an arbitrary geometric shape is shown. A distribution can be formed.

  In the example shown in FIG. 7, an example of the electric field intensity distribution is shown. However, according to the electromagnetic field generator according to the present invention, the phase of the electromagnetic field can be controlled. Therefore, wireless transmission in which information is superimposed on the electromagnetic field intensity and the phase pattern can be realized by temporally changing the electric field intensity and the phase pattern according to the input information signal. In addition, according to the electromagnetic field generation device according to the present embodiment, security authentication based on pattern matching can be performed.

The main effects of this embodiment are summarized as follows.
According to the electromagnetic field generator according to the present embodiment, it is possible to generate surface electromagnetic field distributions of various planar antennas. For example, high gain antenna characteristics simulating an array antenna can be realized.

  In addition, according to the electromagnetic field generator according to the present embodiment, it is possible to freely generate a current distribution that cannot be realized by a conventional antenna element. For example, wireless transmission in which the polarization direction is dynamically modulated is also possible. It becomes free and it becomes possible to provide a wireless communication means with extremely high secrecy.

  In addition, according to the electromagnetic field generation apparatus according to the present embodiment, it is possible to freely generate a current distribution that cannot be realized by a conventional antenna element. For example, the shape and direction of an electric field or a magnetic field can be dynamically changed. Information transmission by electromagnetic waves using advanced modulation that cannot be achieved by conventional wireless transmitters, such as modulated wireless transmission and wireless transmission in which the shape of an equiphase wavefront is modulated by transmission information, becomes possible. Therefore, it is possible to realize large-capacity information transmission while effectively using frequency resources.

(Third embodiment)
Next, a third embodiment of the present invention will be described.
In the present embodiment, the arrangement of the two-dimensional electromagnetic field energy radiating portion in the second embodiment is expanded in three dimensions. That is, in this embodiment, in the configuration of FIG. 6 in the second embodiment, a plurality of electromagnetic energy radiating portions 150x-11,..., 150x-nm, 150y-11,. In addition to nm, a plurality of electromagnetic energy radiation devices 150z (not shown) that generate an electric field or a magnetic field that is orthogonal to the x-axis direction and parallel to the z-axis direction that is orthogonal to the y-axis direction are provided.

  According to the present embodiment, it is possible to place information on the electromagnetic field in the z-axis direction, so that a more complicated electromagnetic field distribution can be generated as compared with the first and second embodiments described above. . In the near field, information can be transmitted by modulating the electric field or magnetic field in the z-axis direction. In addition, if the frequency band is limited, an extremely high transmission capacity can be realized. In the case of wireless information transmission using electromagnetic waves, fluctuations in the electric field or magnetic field in the z-axis direction do not propagate in the z-axis direction, so it is difficult to use the electric field or magnetic field in the z-axis direction for information transmission. Wireless information transmission can be performed using fluctuations in the electromagnetic field in the z-axis direction.

(Fourth embodiment)
Next, a fourth embodiment of the present invention will be described.
In the first to third embodiments described above, an element having a feeding point at the center of the conductor is used as the electromagnetic energy radiating unit. However, in this embodiment, a very long line having feeding points at both ends is used. Use.

  FIG. 8 is a diagram for explaining an example of the configuration (micro-long line type) of the electromagnetic field energy radiation unit 151 included in the electromagnetic field generation apparatus according to the present embodiment. The electromagnetic energy radiating unit 151 corresponds to any one of the electromagnetic energy radiating units 150-1, 150-2, 150-3,..., 150-m shown in FIG. As shown in FIG. 8, the electromagnetic field energy radiating unit 151 includes a very short line 1511. A current I flows through the minute line 1511. The oscillating unit 131 and the resonating unit 141 illustrated in FIG. 8 correspond to the oscillating unit 130 and the resonating unit 140 illustrated in FIG.

  In the electromagnetic field generator according to the present embodiment, the magnetic field generated from the electromagnetic field energy radiating unit 151 is controlled by controlling the current I flowing through the very small line 1511, and the electromagnetic field radiated to the space is controlled. To do. Thereby, similarly to the first to third embodiments described above, an electromagnetic field distribution having a desired geometric shape is obtained. According to experiments, the line length of the line 1511 is desirably 1/8 or less of the wavelength of the radiated electromagnetic wave.

(Fifth embodiment)
Next, a fifth embodiment of the present invention will be described.
In the first to third embodiments described above, an element having a feeding point at the center of a conductor, such as a dipole antenna, is used as the electromagnetic field energy radiating unit. However, in this embodiment, a predetermined interval is used. Parallel plates arranged opposite to each other are used.
FIG. 9 is a diagram for explaining an example of the configuration (micro-parallel plate type) of the electromagnetic field energy radiating unit 152 provided in the electromagnetic field generator according to the fifth embodiment of the present invention. As shown in the figure, the electromagnetic field energy radiating section 152 is composed of minute size parallel plates 1521 and 1522 in which an electric field is generated in a minute section. In FIG. 9, an oscillating unit 132 and a resonating unit 142 are elements corresponding to the oscillating unit 130 and the resonating unit 140 shown in FIG.

In the case of the electromagnetic field generator according to the present embodiment, the electromagnetic field radiated into the space from the electromagnetic energy radiating unit 152 is controlled by controlling the electric field E generated by the voltage applied between the parallel plates of a minute size. . Thereby, similarly to the first to third embodiments described above, an electromagnetic field distribution having a desired geometric shape is obtained. According to the experiment, it is desirable that the section length in which the electric field E is generated be 1/8 or less of the wavelength of the electromagnetic wave to be transmitted.
In the example shown in FIG. 9, one end side of the parallel plates 1521 and 1522 is bent in a direction away from each other. However, as long as a desired electric field E can be formed, the shape of the parallel plates 1521 and 1522 You may form as follows.

(Modification of the first to fifth embodiments)
In the first embodiment described above, when the resonance unit 140 includes a capacitor and an inductor, the leakage of an electric field from the capacitor may be used to function as the electromagnetic field energy emission unit 150. That is, the resonating unit 140 and the electromagnetic field energy radiating unit 150 may be integrally configured. The same applies to the second to fifth embodiments. In this case, the leakage of the electric field from the inductor may be used to function as the electromagnetic field energy radiating unit 150. The same applies to the second to fifth embodiments.

By using the electromagnetic field generation apparatus according to each embodiment of the present invention described above, it is possible to configure an antenna-integrated transmitter that can dynamically control frequency characteristics and radiation characteristics, that is, has programmable antenna characteristics.
In addition, according to each embodiment of the present invention, it is possible to generate a current distribution that is difficult to realize with a conventional conductor-excited antenna, and thus it is possible to realize radiation directivity characteristics that are difficult to realize with a conventional conductor-excited antenna. It becomes possible.
In addition, according to each embodiment of the present invention, the present invention can be used without being restricted by parameters (for example, transmission frequency, communication method, antenna radiation directivity, cell design, etc.) determined in the system design of the wireless communication system. A simple transmitter can be configured.

In addition, according to each embodiment of the present invention, since all hardware that implements the electromagnetic field generator can be configured on a semiconductor monolithic circuit, a system on package (SoP) of a wireless transmitter ).
In addition, according to each embodiment of the present invention, it is possible to freely generate a current distribution that cannot be realized by a conventional antenna element, and thus, for example, wireless transmission in which the polarization direction is dynamically modulated can be freely performed. It is possible to provide wireless communication means with extremely high confidentiality.

  In addition, according to each embodiment of the present invention, it is possible to freely generate a current distribution that cannot be realized by a conventional antenna element. For example, wireless transmission in which the shape and direction of an electric field or a magnetic field are dynamically modulated As in the case of wireless transmission in which the shape of the equiphase wavefront is modulated with transmission information, information transmission by electromagnetic waves using advanced modulation that cannot be achieved by conventional wireless transmitters becomes possible. Therefore, it is possible to carry out large-capacity information transmission while effectively using frequency resources. Further, according to each embodiment of the present invention, since the electromagnetic field distribution can be formed so that the electromagnetic field concentrates in a specific space, it is possible to wirelessly transmit energy in addition to information.

  In each of the embodiments of the present invention described above, the present invention has been described as an electromagnetic field generator, but the operation of the electromagnetic field generator according to each embodiment can also be expressed as an electromagnetic field generation method. In this case, the electromagnetic field generation method according to the present invention includes, for example, a step of generating a high-frequency signal by the plurality of signal generation units 130-1,. ,..., 130-m each radiating high frequency signals generated as electromagnetic fields from the plurality of electromagnetic field radiation units 150-1,..., 150-m to the space, and the plurality of electromagnetic field radiation units 150-1. ,..., 150-m so that the oscillation control unit 120 forms an electromagnetic field distribution having a desired geometric shape in the space. It can be expressed as an electromagnetic field generation method including a step of controlling. However, you may further provide the step corresponding to operation | movement of the resonance parts 140-1, ..., 140-m.

Finally, a supplementary description will be given of the resonance unit included in the electromagnetic field generation device of each of the above-described embodiments.
Here, the resonance unit 140-1 of the electromagnetic field generation device 100 according to the first embodiment shown in FIG. 1 will be described as an example. The same applies to the other resonance parts.
FIG. 10A shows an example of the configuration of the resonating unit 140-1. In this example, the resonance unit 140-1 is configured as a parallel resonance circuit from the variable inductor L and the variable capacitor C. Here, in the example of FIG. 10A, one of the pair of feed lines in which the positive-phase high-frequency signal of the signal generation unit 130-1 is connected to the feed point of the electromagnetic energy radiating unit 150-1. (For example, a power supply line connected to the conductor 150a shown in FIG. 2B), and the high-frequency signal of the opposite phase of the signal generator 130-1 is the other of the pair of power supply lines (for example, FIG. 2 (b), the power supply line connected to the conductor portion 150b). A variable inductor L and a variable capacitor C are connected in parallel between these feeder lines. The oscillation control unit 120 sets the frequency of the oscillator of the signal generation unit 130-1 according to the desired electromagnetic field distribution geometry, and causes the resonance state of the resonance unit 140-1 to cause a resonance state with respect to this frequency. The inductance of the variable inductor L and the capacitance of the variable capacitor C are adjusted.

  Note that the present invention is not limited to this example, and the resonance unit 140-1 may be configured as a series resonance circuit from the variable inductor L and the variable capacitor C. For example, the resonance unit 140-1 may be configured as a frequency variable resonator using a varactor or the like. . Alternatively, the resonance unit 140-1 may be configured as a distributed constant circuit. That is, the circuit configuration of the resonance unit 140-1 is arbitrary as long as it can cause a resonance phenomenon. The same applies to other resonance parts.

Moreover, the resonance part 140-1 and the electromagnetic field energy radiation | emission part 150-1 can also be comprised integrally by utilizing a half wavelength dipole antenna.
FIG. 10B shows an example in which a resonating unit 140-1 and an electromagnetic field energy radiating unit 150-1 are integrally configured using a half-wave dipole antenna. The same applies to other resonating parts and electromagnetic energy radiating parts.

  As shown in FIG. 10B, a half-wave dipole is formed at a point P corresponding to ½ of the length L shown in FIG. 2 with the feed point to which the signal generator 130-1 is connected as a base point. Each of the two antenna elements of the antenna is bent at a right angle so that the antenna elements are parallel to each other. Of the total length of each antenna element, portions AL and AR corresponding to ½ of the length L from the feeding point function as the electromagnetic field energy radiating unit 150-1. Since the electromagnetic fields radiated from the other portions BL and BR cancel each other, these portions BL and BR can be ignored in appearance. If the length L is set to be as small as possible (that is, if the electromagnetic field energy radiating portion is configured as a microelement), the antenna element portions AL and AR are divided into portions BL and BR. On the other hand, the length of each of the portions BL and BR becomes about 1/4 wavelength.

  According to the example shown in FIG. 10B, the portions AL and AR corresponding to ½ of the length L from the feeding point are located in the antinode portion of the current distribution of the half-wavelength dipole antenna. For this reason, it becomes possible to radiate | emit an electromagnetic field efficiently. Further, if the resonance frequency of the half-wave dipole antenna is matched with the frequency of the high-frequency signal output from the signal generator 130-1, power efficiency is not impaired. A balun may be added in the example shown in FIG.

Although the embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiment, and can be arbitrarily modified or modified without departing from the gist of the present invention.
For example, in the above-described embodiment, a plurality of electromagnetic field energy radiating portions are arranged in a one-dimensional, two-dimensional, and three-dimensional grid. However, the present invention is not limited to this, for example, according to the type of information to be transmitted, etc. , It can be arranged in any form.

  Further, in the above-described embodiment, the plurality of signal generation units 130-1, ..., 130-m are provided. However, as long as the electromagnetic fields radiated by the plurality of electromagnetic energy emission units can be individually controlled, The plurality of signal generators 130-1,..., 130-m may be configured as one unit, and whether the signal generators are plural or singular is not the essence of the present invention. Therefore, in the claimed invention, “a plurality of signal generation units” may be expressed as “a single signal generation unit”. The same applies to “a plurality of resonance portions”.

  100: Electromagnetic field generator, 110: Information input terminal, 120: Oscillation controller, 130, 130-1,..., 130-m, 131, 132: Signal generator, 140, 140-1,. , 141, 142: resonance part, 150, 150-1,..., 150-m, 150x-11,..., 150x-nm, 150y-11, ..., 150y-nm: electromagnetic energy radiating part, 150a, 150b: Conductor part.

Claims (9)

A plurality of signal generators for generating high-frequency signals;
A plurality of electromagnetic field radiating units that radiate high-frequency signals generated by each of the plurality of signal generating units to space as electromagnetic fields;
Control for controlling the plurality of signal generation units so that electromagnetic fields radiated from the plurality of electromagnetic field radiation units respectively form an electromagnetic field distribution having a geometric shape modulated according to an input information signal in the space. And an electromagnetic field generator. The geometry of the field distribution, the electromagnetic field generator according to claim 1, wherein the geometric shape of the equiphase wavefront in the electromagnetic field distribution. The plurality of resonating units that resonate with the high-frequency signals generated by each of the plurality of signal generating units are provided between the plurality of signal generating units and the plurality of electromagnetic field radiating units. The electromagnetic field generator according to 1 or 2 . Said plurality of electromagnetic field radiation portion has a smaller size than the wavelength of the electromagnetic field, each emitting, each according to claim 3, characterized in that closely spaced than the wavelength of the electromagnetic field that radiates Electromagnetic field generator. Each size of the plurality of electromagnetic field radiation portions is 1/8 or less of the smallest wavelength of the electromagnetic field to be radiated, and the number of the plurality of electromagnetic field radiation portions is 4 or more. The electromagnetic field generator according to claim 4 . Electromagnetic field generating device according to any one of claims 3 to 5, characterized in that each of the Q value of the plurality of resonator units is 10 or more. The control unit determines one or more of the frequency, amplitude, phase, and waveform of the high-frequency signal generated by the plurality of signal generation units and the resonance frequency of the plurality of resonance units according to the input information signal. by varying electromagnetic field generator according to any one of claims 3 to 6, characterized by modulating the geometry of the electromagnetic field distribution.   8. The electromagnetic wave according to claim 1, wherein the plurality of electromagnetic field radiation portions are arranged in any one of a one-dimensional shape, a two-dimensional shape, and a three-dimensional shape. Field generator. Generating a high-frequency signal by a plurality of signal generators;
Radiating high-frequency signals respectively generated by the plurality of signal generation units as electromagnetic fields from the plurality of electromagnetic field emission units;
The controller generates the plurality of signal generators so that the electromagnetic fields radiated from the plurality of electromagnetic field emitters form an electromagnetic field distribution having a geometric shape modulated according to an input information signal in the space. An electromagnetic field generating method including the step of controlling.