Radio communication device and radio communication system

Abstract

To provide a radio communication device capable of performing beamforming in simple configuration, and a radio communication system.SOLUTION: In a radio communication system 1, a radio communication device 100 comprises: a transmit array 110 which is actuated as a variable lens; a transmission section 120 which radiates an optical signal TxOS for transmission from a base station device 200 to the transmit array; a reception section 130 which receives a radio signal for reception arriving at the transmit array and sends an optical signal RxOS for reception to the base station device; and a control section 140 including a controller 141 which individually controls the transmit array. The transmission section includes: a light-receiving element 121 which converts the optical signal for transmission into an electric signal for transmission; an amplifier 122 for transmission which amplifies the electric signal for transmission; and a transmission antenna 123 which radiates the amplified electric signal for transmission. The reception section includes an antenna integrated electro-optical modulator 131 which modulates the radio signal for reception with the optical signal from the light-emitting element 132 and generates the optical signal for reception.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a wireless communication device and a wireless communication system. [Background technology]

[0002] Wireless communication systems use a technology called RoF (Radio over Fiber), which transmits the waveform information of wireless signals over optical fibers. Known types of RoF include D-RoF (Digital Radio over Fiber) and A-RoF (Analog Radio over Fiber).

[0003] D-RoF is a technology that converts the waveform information of a wireless signal into a digital signal and then transmits it over optical fiber. However, D-RoF has the following problems: (1) Because the transmission capacity required for transmitting digital signals is large, optical communications cannot keep up with next-generation high-capacity communications. (2) Since various processes such as DSP (Digital Signal Processing) are performed in the RU (Radio Unit), increasing the number of RUs to realize wireless communication in high frequency bands increases costs accordingly. (3) The power consumption for processing in the RU is large.

[0004] In contrast, A-RoF is a technology that transmits the waveform information of a radio signal as an analog signal over optical fiber. Unlike D-RoF, A-RoF does not require various processing steps in the RU, such as DSP. Therefore, in order to solve the above-mentioned problems that can be considered with D-RoF, A-RoF is being considered instead of D-RoF, and the RU functions are consolidated into a Distributed Unit (DU) or Centralized Unit (CU). This would separate the antenna element from the central station, simplifying the RU while reducing the cost and power consumption associated with the RU.

[0005] On the other hand, in wireless communication systems using high frequency bands, the propagation distance of radio waves is shorter, so beamforming is required. However, as mentioned above, when RU is simplified by A-RoF, the issue of how to perform beamforming with antenna elements becomes an issue.

[0006] To address the above-mentioned issues, a technology has been proposed in which the beams formed by the antenna elements are remotely controlled from the central station. Patent Document 1 discloses a technology related to wireless communication that uses an optical lens as a beam former to transmit and receive signals. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] US Patent Application Publication No. 2022 / 0166137 Summary of the Invention [Problem to be solved by the invention]

[0008] The technology described in Patent Document 1 allows the central station to remotely control the beams formed by the antenna elements, but requires an optical communication path for each antenna element. Therefore, multiplexing increases the number of optical fibers, which creates a problem of making the overall system configuration more complex.

[0009] The present invention has been made to solve the above problems, and has an object to provide a wireless communication device capable of beamforming with a simple configuration, and a wireless communication system using the wireless communication device of the present invention. [Means for solving the problem]

[0010] A wireless communication device of the present invention includes a transmit array including a plurality of antenna elements and operating as a variable lens, a transmitter unit that receives a transmission optical signal from a base station device and radiates a transmission radio signal corresponding to the transmission optical signal to the transmit array, a receiver unit that receives a reception radio signal arriving at the transmit array and transmits a reception optical signal corresponding to the reception radio signal to the base station device, and a controller that controls the transmit array. The transmitter unit includes a photodetector that converts the transmission optical signal into a transmission electrical signal, a transmission amplifier that amplifies the transmission electrical signal, and a transmission antenna that radiates the transmission radio signal corresponding to the transmission electrical signal amplified by the transmission amplifier. The receiver unit includes an antenna-integrated electro-optic modulator that modulates an optical signal from a light-emitting element based on the reception radio signal to generate the reception optical signal. The antenna-integrated electro-optic modulator includes an optical waveguide that transmits the optical signal from the light-emitting element, and a receiving antenna arranged along the optical waveguide that receives the reception radio signal. The control unit includes a controller that individually controls the phase of radio waves transmitted and received by each antenna element of the transmit array. The transmit antenna and the receive antenna are disposed at positions spaced apart from each other on a light-collecting surface that can be formed by the transmit array.

[0011] A wireless communication system of the present invention includes the wireless communication device of the present invention, a base station device, and an optical transmission member connecting the wireless communication device and the base station device. [Effects of the Invention]

[0012] According to the present invention, it is possible to provide a wireless communication device capable of beamforming with a simple configuration. Furthermore, according to the present invention, it is possible to provide a wireless communication system using the wireless communication device of the present invention. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 1 is a schematic diagram showing an example of a wireless communication system using a wireless communication device according to an embodiment of the present invention. [Figure 2] FIG. 2 is a perspective view schematically illustrating an example of an antenna-integrated electro-optical modulator. [Figure 3] FIG. 3 is a schematic diagram showing an example of a lens pattern of a transmit array during transmission. [Figure 4] FIG. 4 is a schematic diagram showing an example of a lens pattern of a transmit array during reception. [Figure 5] FIG. 5 is a schematic diagram showing an example of a wireless communication system using a wireless communication device according to another embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0014] The wireless communication device of the present invention will be described below. Note that the present invention is not limited to the following configuration, and may be modified as appropriate without departing from the spirit of the present invention. Furthermore, a combination of multiple individual preferred configurations described below also constitutes the present invention.

[0015] In this specification, terms indicating the relationship between elements (e.g., "perpendicular," "parallel," "orthogonal," etc.) and terms indicating the shape of elements are not expressions that express only strict meanings, but are expressions that also include a range of substantial equivalence, for example, a difference of a few percent.

[0016] The drawings shown below are schematic diagrams, and the dimensions, aspect ratio, and other scales may differ from those of the actual product. In the drawings, the same or equivalent parts will be designated by the same reference numerals. In addition, the same elements will be designated by the same reference numerals in each drawing, and duplicate explanations will be omitted.

[0017] FIG. 1 is a schematic diagram showing an example of a wireless communication system using a wireless communication device according to an embodiment of the present invention.

[0018] The wireless communication system 1 shown in FIG. 1 includes a wireless communication device 100, a base station device 200, and an optical transmission member 300 that connects the wireless communication device 100 and the base station device 200.

[0019] The wireless communication device 100 is, for example, a remote radio unit (RRU).

[0020] The base station device 200 is, for example, a radio unit (RU).

[0021] The light transmission component 300 is, for example, an optical fiber. Each light transmission component 300 may be a single optical fiber, or an optical fiber cable formed by bundling a plurality of optical fibers.

[0022] As shown in FIG. 1, wireless communication device 100 includes a transmit array 110, a transmitter 120, a receiver 130, and a controller 140.

[0023] The transmit array 110 is a parasitic antenna array including multiple antenna elements. In the transmit array 110, for example, multiple antenna elements are formed on a printed circuit board, and a control element such as a diode is mounted on each antenna element. The control element may be a varactor diode or a liquid crystal. Each antenna element may be provided with wiring for applying a bias voltage to the control element. As will be described later, the transmit array 110 operates as a variable lens.

[0024] The transmitter 120 receives the optical signal TxOS for transmission from the base station apparatus 200 and emits a radio signal for transmission (see FIG. 3 described later) corresponding to the optical signal TxOS for transmission to the transmit array 110.

[0025] Specifically, the transmitter 120 includes a light receiving element 121 , a transmitting amplifier 122 , and a transmitting antenna 123 .

[0026] The light receiving element 121 converts the transmission optical signal TxOS into a transmission electrical signal TxES. The light receiving element 121 is, for example, a photodiode (PD).

[0027] The transmission amplifier 122 amplifies the transmission electrical signal TxES. The transmission amplifier 122 is, for example, a power amplifier (PA).

[0028] The transmitting antenna 123 emits a transmitting radio signal corresponding to the transmitting electrical signal TxES amplified by the transmitting amplifier 122. The configuration of the transmitting antenna 123 is not particularly limited.

[0029] The receiver 130 receives radio signals to be received (see FIG. 4, which will be described later) arriving at the transmit array 110, and sends to the base station apparatus 200 optical signals to be received RxOS corresponding to the radio signals to be received.

[0030] Specifically, the receiving section 130 includes an antenna-integrated electro-optic modulator 131 .

[0031] The antenna-integrated electro-optic modulator 131 modulates the optical signal from the light-emitting element 132 based on the radio signal to be received to generate the optical signal to be received RxOS. The light-emitting element 132 is, for example, a laser diode (LD).

[0032] FIG. 2 is a perspective view schematically illustrating an example of an antenna-integrated electro-optical modulator.

[0033] 2, the antenna-integrated electro-optic modulator 131 includes an optical waveguide 133 that transmits an optical signal from the light-emitting element 132 (see FIG. 1), and a receiving antenna 134 that is arranged along the optical waveguide 133 and receives a radio signal to be received. The antenna-integrated electro-optic modulator 131 may further include a substrate 135.

[0034] The antenna-integrated electro-optic modulator 131 functions as a modulator that modulates an optical signal by the electro-optic effect using a radio signal received by a receiving antenna 134 in the following manner.

[0035] In the antenna-integrated electro-optic modulator 131, an optical signal from the light-emitting element 132 (see FIG. 1) is transmitted to the optical waveguide 133. Meanwhile, the receiving antennas 134 each receive a radio signal. At this time, a resonance phenomenon occurring in the receiving antenna 134 increases the electric field, and an electro-optic effect occurs in the optical waveguide 133 passing through the area where this electric field is generated. When the electro-optic effect occurs in the optical waveguide 133, the refractive index of the optical waveguide 133 with respect to the optical signal transmitted to the optical waveguide 133 changes, and a phase change occurs in the optical signal according to the magnitude of the electric field. In this way, the antenna-integrated electro-optic modulator 131 modulates the optical signal transmitted to the optical waveguide 133 by the electro-optic effect using the radio signal received by the receiving antenna 134. In other words, the antenna-integrated electro-optic modulator 131 utilizes the electro-optic effect to directly superimpose the radio signal received by the receiving antenna 134 on the optical signal transmitted to the optical waveguide 133.

[0036] The configuration of the receiving antenna 134 is not particularly limited. In the example shown in Fig. 2, each receiving antenna 134 is configured with two planar electrodes 134a and 134b adjacent to each other in a direction perpendicular to the extension direction of the optical waveguide 133, and a gap is formed between the planar electrodes 134a and 134b (at the center of the receiving antenna 134 in Fig. 2). For example, the planar electrodes 134a and 134b are both rectangular and are arranged symmetrically across the gap. The shorter the gap, the stronger the electric field can be near the sides where the planar electrodes 134a and 134b face each other.

[0037] The control unit 140 controls the transmit array 110 .

[0038] The control unit 140 includes a controller 141 that individually controls the phase of radio waves transmitted and received by each antenna element of the transmit array 110, with the aim of varying the main lobe direction of the beam pattern of the transmit array 110. The controller 141 includes, for example, a circuit for changing the voltage applied to a diode provided in each antenna element.

[0039] The controller 141 preferably receives from the base station device 200 a control optical signal CtOS that controls switching of the main lobe direction of the beam pattern by the transmit array 110. In other words, it is preferable that the control optical signal from the base station device 200 individually controls the phase of the radio waves transmitted and received by each antenna element of the transmit array 110.

[0040] In this case, the controller 141 includes, for example, a light receiving element (such as a photodiode) that converts the control optical signal CtOS into a current signal, a current-voltage conversion element that converts the current signal into a voltage signal, and an integrated circuit (IC) that controls the DC voltage applied to the transmit array 110.

[0041] In the wireless communication device 100, the transmitting antenna 123 and the receiving antenna 134 are arranged at positions separated from each other on the light-collecting surface that the transmit array 110 can form.

[0042] As described above, the phase of the radio waves emitted by each antenna element of the transmit array 110 is individually controlled. By assigning a specific distribution to each phase, the transmit array 110 operates as a variable lens. The phase distribution can be expressed, for example, by a hyperbolic function with a specific focal length.

[0043] Therefore, by individually controlling the phase of the radio waves transmitted and received by each antenna element of the transmit array 110, the focal position of the transmit array 110 can be aligned with the transmitting antenna 123 during transmission and with the receiving antenna 134 during reception.

[0044] Specifically, the control unit 140 adjusts the focal position of the transmit array 110 to the transmitting antenna 123 during transmission and to the receiving antenna 134 during reception.

[0045] FIG. 3 is a schematic diagram showing an example of a lens pattern of a transmit array during transmission.

[0046] 3, during transmission, a transmission focal position 112Tx of a virtual transmission lens 111Tx formed by the transmit array 110 is aligned with the transmission antenna 123. This allows the radio waves of the transmission radio signal TxRS radiated from the transmission antenna 123 to be collimated. Therefore, the radio waves of the transmission radio signal TxRS radiated from the transmission antenna 123 can be sent out with high gain.

[0047] FIG. 4 is a schematic diagram showing an example of a lens pattern of a transmit array during reception.

[0048] 4, during reception, the reception focal position 112Rx of the virtual reception lens 111Rx formed by the transmit array 110 is aligned with the reception antenna 134 (see FIG. 2) of the antenna-integrated electro-optic modulator 131. This allows the radio waves of the reception radio signal RxRS arriving at the transmit array 110 to be focused onto the antenna-integrated electro-optic modulator 131.

[0049] In this way, by placing the transmitting antenna 123 and the receiving antenna 134 at separate positions on the focusing surface that can be formed by the transmit array 110, spatial separation of transmission and reception becomes possible using the beam spot formed by the transmit array 110.

[0050] Furthermore, a feature of the transmit array 110 is that it can tilt the beam by changing the lens pattern at each focal position during transmission and reception. This makes it possible to perform beamforming simply by disposing the transmit array 110, without providing the transmitter 120 and receiver 130 with a beamforming function.

[0051] As described above, the wireless communication device 100 shown in FIG. 1 can perform beamforming both during transmission and reception with a simple configuration including the transmit array 110, the transmitter 120, the receiver 130, and the controller 140.

[0052] Therefore, for example, even when two-dimensional beam scanning is performed in the wireless communication device 100, the device does not need to be made complex.

[0053] Furthermore, in the wireless communication device 100, the number of optical transmission members 300 required for the base station device 200 to perform beamforming can be reduced to three: one for transmission, one for reception, and one for control.

[0054] Furthermore, by using the antenna-integrated electro-optical modulator 131 in the receiver 130, a receiver amplifier is not required, which reduces the power consumption of the RRU portion.

[0055] In the wireless communication device 100, the distance between the transmitting antenna 123 and the receiving antenna 134 is preferably larger than the size of the beam spot formed by the transmit array 110. In addition, the distance between the transmitting antenna 123 and the receiving antenna 134 is preferably equal to or larger than the wavelength λ of the operating frequency band.

[0056] In the wireless communication device 100, for example, the power supply to the light-emitting element 132 of the receiving unit 130 may be turned off during transmission. In this case, interference can be further isolated. Also, the bias voltage of the light-receiving element 121 of the transmitting unit 120 may be reduced during reception. In this case, interference can be further removed.

[0057] 2, one optical waveguide 133 is provided in the antenna-integrated electro-optic modulator 131. The number of optical waveguides 133 is not particularly limited, and may be one, or two or more.

[0058] 2, the optical waveguide 133 extends linearly when viewed from the main surface side of the substrate 135, but may extend in a curved manner when viewed from the main surface side of the substrate 135. In this case, the optical waveguide 133 may be bent in a broken line or curved line.

[0059] The optical waveguide 133 is preferably made of an electro-optic material.

[0060] When an electric field is applied to an electro-optic material, the refractive index of the material changes and the phase of the light changes, thereby exhibiting an electro-optic effect.

[0061] The optical waveguide 133 is preferably made of an electro-optical polymer containing electro-optical molecules as the electro-optical material.

[0062] An electro-optic polymer is a polymer that is capable of exhibiting an electro-optic effect.

[0063] Examples of electro-optical polymers include guest-host electro-optical polymers in which a matrix polymer and electro-optical molecules are mixed, side-chain electro-optical polymers in which electro-optical molecules are covalently bonded to the side chains of a base polymer, main-chain electro-optical polymers in which electro-optical molecules are covalently bonded to the main chain of a base polymer, cross-linked electro-optical polymers in which cross-linking occurs between matrix polymers or base polymers, or between matrix polymers or base polymers and electro-optical molecules, and molecular glass electro-optical polymers.

[0064] The matrix polymer is the polymer that serves as the base for the electro-optic polymer. The matrix polymer includes an organic polymer that serves as the host for the guest-host electro-optic polymer.

[0065] The base polymer is a polymer that forms the basic skeleton of the electro-optic polymer, and includes an organic polymer that forms the main chain of a polymer in a side-chain electro-optic polymer, a main-chain electro-optic polymer, or a cross-linked electro-optic polymer.

[0066] The matrix polymer and base polymer are preferably transparent polymers that do not scatter light in order to be used as optical materials, and examples thereof include (meth)acrylate polymers, polyamides, polyimides, polycarbonates, polydicyclopentanyl methacrylate, polyadamantyl methacrylate, cycloolefin polymers, cycloolefin copolymers, polynorbornenes, polystyrenes, polyethylenes, polymethylpentenes, polypropylenes, polyvinyl alcohols, polyethylene terephthalates, polysulfones, polyethersulfones, polyesters, polyolefins, polyphenylene sulfide, polyureas, silicone resins, epoxy resins, fluororesins, etc. As the matrix polymer and base polymer, these organic polymers may be used alone or in combination of two or more types.

[0067] Electro-optic molecules are compounds capable of exhibiting an electro-optic effect.

[0068] The electro-optic molecule is preferably a compound having a conjugated chemical structure and further having an electron-donating group and an electron-withdrawing group in the molecule.

[0069] Examples of conjugated chemical structures include aromatic compounds such as benzene, naphthalene, anthracene, perylene, biphenyl, indene, and stilbene; heterocyclic compounds such as furan, pyran, pyrrole, imidazole, pyrazole, thiophene, thiazole, pyridine, pyridazine, pyrimidine, pyrazine, quinoline, and coumarin; and compounds in which these compounds are bonded to each other via a carbon-carbon unsaturated bond or a nitrogen-nitrogen unsaturated bond.

[0070] Examples of the electron-donating group include an amino group which may be substituted with an alkyl group, an aryl group, or an acyl group, an alkoxy group, an allyloxy group, and a thioether group.

[0071] Examples of the electron-withdrawing group include a nitro group, a cyano group, a dicyanovinyl group, a tricyanovinyl group, a halogen atom, a carbonyl group, a sulfone group, a perfluoroalkyl, a tricyanovinylfuran, and a tricyanofuran.

[0072] The optical waveguide 133 may be made of an electro-optical material such as a ferroelectric material having optical anisotropy, such as lithium niobate (LiNbO3), lithium tantalate (LiTaO3), or potassium titanyl phosphate (KTiOPO4:KTP).

[0073] The receiving antenna 134 is preferably provided on the main surface of the substrate 135 .

[0074] 2, there are provided three receiving antennas 134. The number of receiving antennas 134 is not limited to three as long as there is more than one, and may be two, or four or more.

[0075] Preferably, an optical waveguide 133 is provided inside the substrate 135 so as to extend along the main surface of the substrate 135 .

[0076] The substrate 135 may be made up of only one layer, or may be made up of multiple layers.

[0077] The substrate 135 may include, for example, a support base 136 and an electro-optical layer 137, in that order toward the receiving antenna 134. In this case, the optical waveguide 133 is preferably provided between the support base 136 and the electro-optical layer 137. In addition, the receiving antenna 134 is preferably provided on the surface of the electro-optical layer 137 opposite to the support base 136.

[0078] The constituent material of the support substrate 136 may be, for example, an inorganic material such as silicon or glass, or an organic material such as a cycloolefin polymer or a cycloolefin copolymer. The support substrate 136 may contain only one type of these materials, or may contain multiple types of materials.

[0079] It is preferable that at least the main surface of support substrate 136 facing receiving antenna 134 is made of a material with a low dielectric constant, such as cycloolefin polymer. In this case, optical waveguide 133 is preferably provided on the main surface of support substrate 136 facing receiving antenna 134.

[0080] The support substrate 136 may be made up of only one layer, or may be made up of multiple layers.

[0081] Examples of materials constituting the electro-optical layer 137 include ferroelectric materials having optical anisotropy, such as lithium niobate (LiNbO3), lithium tantalate (LiTaO3), and potassium titanate phosphate (KTiOPO4:KTP).

[0082] The electro-optical layer 137 may be made up of only one layer, or may be made up of multiple layers.

[0083] Although not shown in FIG. 2, the antenna-integrated electro-optic modulator 131 may further include a ground electrode.

[0084] The ground electrode may be provided on the principal surface of the substrate 135 opposite to the principal surface on which the receiving antenna 134 is provided, or may be provided inside the substrate 135. In either case, the optical waveguide 133 is located between the ground electrode and the receiving antenna 134.

[0085] The material of the ground electrode may be the same as or different from the material of the receiving antenna 134 .

[0086] In the above embodiment, the receiving unit includes an antenna-integrated electro-optical modulator, but for example, as in the wireless communication device below, the receiving unit may include, instead of the antenna-integrated electro-optical modulator, a receiving antenna that receives a receiving radio signal and generates a receiving electrical signal, a receiving amplifier that amplifies the receiving electrical signal, and an electro-optical modulator that modulates an optical signal from a light-emitting element based on the receiving electrical signal amplified by the receiving amplifier to generate a receiving optical signal.

[0087] a transmit array including a plurality of antenna elements and operating as a variable lens; a transmitter that receives a transmission optical signal from a base station device and emits a transmission radio signal corresponding to the transmission optical signal to the transmit array; a receiving section that receives a radio signal to be received arriving at the transmit array and transmits an optical signal to be received corresponding to the radio signal to be received to the base station device; a control unit for controlling the transmit array, the transmitting unit includes a light receiving element that converts the transmission optical signal into a transmission electrical signal, a transmission amplifier that amplifies the transmission electrical signal, and a transmitting antenna that radiates the transmission radio signal corresponding to the transmission electrical signal amplified by the transmission amplifier, the receiving unit includes a receiving antenna that receives the receiving radio signal and generates a receiving electrical signal, a receiving amplifier that amplifies the receiving electrical signal, and an electro-optical modulator that modulates an optical signal from a light-emitting element based on the receiving electrical signal amplified by the receiving amplifier to generate a receiving optical signal; the control unit includes a controller that individually controls the phase of radio waves transmitted and received by each antenna element of the transmit array; The wireless communication device, wherein the transmitting antenna and the receiving antenna are disposed at positions spaced apart from each other on a light-collecting plane that can be formed by the transmit array.

[0088] FIG. 5 is a schematic diagram showing an example of a wireless communication system using a wireless communication device according to another embodiment of the present invention.

[0089] The wireless communication system 1A shown in FIG. 5 includes a wireless communication device 100A, a base station device 200, and an optical transmission member 300 connecting the wireless communication device 100 and the base station device 200.

[0090] The wireless communication system 1A has a common configuration with the wireless communication system 1, except that the wireless communication system 1A includes a wireless communication device 100A instead of the wireless communication device 100.

[0091] As shown in FIG. 5, wireless communication device 100A includes a transmit array 110, a transmitting unit 120, a receiving unit 130A, and a control unit 140.

[0092] The wireless communication device 100A has a common configuration with the wireless communication device 100, except that the wireless communication device 100A includes a receiving unit 130A instead of the receiving unit 130.

[0093] The receiving unit 130A includes a receiving antenna 134 that receives a receiving radio signal (see FIG. 4) arriving at the transmit array 110 and generates a receiving electrical signal RxES, a receiving amplifier 138 that amplifies the receiving electrical signal RxES, and an electro-optical modulator 139 that modulates the optical signal from the light-emitting element 132 based on the receiving electrical signal RxES amplified by the receiving amplifier 138 to generate a receiving optical signal RxOS. The receiving amplifier 138 is, for example, a low noise amplifier (LNA).

[0094] In the wireless communication device 100A, the transmitting antenna 123 and the receiving antenna 134 are arranged at positions separated from each other on the light collecting plane that can be formed by the transmit array 110. This allows the wireless communication device 100A to achieve the same effects as the wireless communication device 100.

[0095] The present specification discloses the following:

[0096] <1> a transmit array including a plurality of antenna elements and operating as a variable lens; a transmitter that receives a transmission optical signal from a base station device and emits a transmission radio signal corresponding to the transmission optical signal to the transmit array; a receiving section that receives a radio signal to be received arriving at the transmit array and transmits an optical signal to be received corresponding to the radio signal to be received to the base station device; a control unit for controlling the transmit array, the transmitting unit includes a light receiving element that converts the transmission optical signal into a transmission electrical signal, a transmission amplifier that amplifies the transmission electrical signal, and a transmitting antenna that radiates the transmission radio signal corresponding to the transmission electrical signal amplified by the transmission amplifier, the receiving unit includes an antenna-integrated electro-optic modulator that modulates an optical signal from a light-emitting element based on the receiving radio signal to generate the receiving optical signal, the antenna-integrated electro-optic modulator includes an optical waveguide that transmits an optical signal from the light-emitting element, and a receiving antenna that is disposed along the optical waveguide and receives the reception radio signal, the control unit includes a controller that individually controls the phase of radio waves transmitted and received by each antenna element of the transmit array; The wireless communication device, wherein the transmitting antenna and the receiving antenna are disposed at positions spaced apart from each other on a light-collecting plane that can be formed by the transmit array.

[0097] <2> the controller receives from the base station device a control optical signal for individually controlling the phase of radio waves transmitted and received by each antenna element of the transmit array; <1> The wireless communication device described in

[0098] <3> the control unit aligns the focal position of the transmit array with the transmitting antenna during transmission and with the receiving antenna during reception; <1> or <2> The wireless communication device described in

[0099] <4> a distance between the transmitting antenna and the receiving antenna is greater than a beam spot size formed by the transmit array; <1> ~ <3> 10. A wireless communication device according to claim 9, wherein:

[0100] <5> The distance between the transmitting antenna and the receiving antenna is equal to or greater than the wavelength λ of the operating frequency band. <1> ~ <4> 10. A wireless communication device according to claim 9, wherein:

[0101] <6> The antenna-integrated electro-optic modulator further includes a substrate; The optical waveguide is provided inside the substrate so as to extend along a main surface of the substrate. <1> ~ <5> 10. A wireless communication device according to claim 9, wherein:

[0102] <7> The optical waveguide is made of an electro-optic polymer containing electro-optic molecules. <1> ~ <6> 10. A wireless communication device according to claim 9, wherein:

[0103] <8> <1> ~ <7> a base station device; and an optical transmission member connecting the wireless communication device and the base station device. [Explanation of symbols]

[0104] 1. 1A wireless communication system 100, 100A wireless communication device 110 Transmit Array 111Rx receiving lens 111Tx Transmitting Lens 112Rx Reception focal position 112Tx Transmission focal position 120 Transmitter 121 Photodetector 122 Transmitting amplifier 123 transmitting antenna 130, 130A receiving unit 131 Antenna-integrated electro-optic modulator 132 Light-emitting element 133 Optical waveguide 134 receiving antenna 134a, 134b Planar electrode 135 PCB 136 Supporting base material 137 Electro-optical layer 138 Receiving amplifier 139 Electro-optic Modulator 140 Control Unit 141 Controller 200 Base station equipment 300 Optical transmission components CtOS control optical signal RxES Receive electrical signal RxOS receiving optical signal RxRS reception radio signal TxES Electrical signal for transmission TxOS optical signal for transmission TxRS radio signal for transmission

Claims

1. a transmit array including a plurality of antenna elements and operating as a variable lens; a transmitter that receives a transmission optical signal from a base station device and emits a transmission radio signal corresponding to the transmission optical signal to the transmit array; a receiving unit that receives a radio signal to be received arriving at the transmit array and transmits an optical signal to be received corresponding to the radio signal to be received to the base station device; a control unit for controlling the transmit array, the transmitting unit includes a light receiving element that converts the transmission optical signal into a transmission electrical signal, a transmission amplifier that amplifies the transmission electrical signal, and a transmitting antenna that radiates the transmission radio signal corresponding to the transmission electrical signal amplified by the transmission amplifier, the receiving unit includes an antenna-integrated electro-optic modulator that modulates an optical signal from a light-emitting element based on the receiving radio signal to generate the receiving optical signal; the antenna-integrated electro-optic modulator includes an optical waveguide that transmits an optical signal from the light-emitting element, and a receiving antenna that is disposed along the optical waveguide and receives the reception radio signal, the control unit includes a controller that individually controls the phase of radio waves transmitted and received by each antenna element of the transmit array; A wireless communication device, wherein the transmitting antenna and the receiving antenna are arranged at positions spaced apart from each other on a light-collecting plane that can be formed by the transmit array.

2. The wireless communication device according to claim 1 , wherein the controller receives from the base station an optical control signal for individually controlling the phase of radio waves transmitted and received by each antenna element of the transmit array.

3. 3. The wireless communication device according to claim 1, wherein the control unit aligns the focal position of the transmit array with the transmitting antenna during transmission and with the receiving antenna during reception.

4. 3. The wireless communication device according to claim 1, wherein the distance between the transmitting antenna and the receiving antenna is greater than the size of a beam spot formed by the transmit array.

5. 3. The wireless communication device according to claim 1, wherein the distance between the transmitting antenna and the receiving antenna is equal to or greater than the wavelength λ of an operating frequency band.

6. The antenna-integrated electro-optic modulator further includes a substrate; 3. The wireless communication device according to claim 1, wherein the optical waveguide is provided inside the substrate so as to extend along a main surface of the substrate.

7. 3. The wireless communication device according to claim 1, wherein the optical waveguide is made of an electro-optic polymer containing electro-optic molecules.

8. 3. A wireless communication system comprising: the wireless communication device according to claim 1; a base station device; and an optical transmission member connecting the wireless communication device and the base station device.

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