Antenna device and communication device

Abstract

To provide an antenna device and a communication device that can improve characteristics.SOLUTION: According to an embodiment, an antenna device includes a plurality of left phase shifters, a plurality of right phase shifters, and a plurality of antennas. The plurality of left phase shifters include first and second left phase shifters. The plurality of right phase shifters include first and second right phase shifters. The plurality of antennas include first and second antennas. The first and second left phase shifters supply first and second left-handed circularly polarized signals to the first and second antennas, respectively. The first and second right phase shifters supply first and second right-handed circularly polarized signals to the first and second antennas, respectively. The first and second antennas transmit first and second left-handed circularly polarized waves based on the first and second left-handed circularly polarized signals, and first and second right-handed circularly polarized waves based on the first and second right-handed circularly polarized signals, respectively. The polarization angle of a linearly polarized wave generated by the first left-handed circularly polarized wave and the first right-handed circularly polarized wave is different from the polarization angle of a linearly polarized wave generated by the second left-handed circularly polarized wave and the second right-handed circularly polarized wave.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] FIELD An embodiment of the present invention relates to an antenna device and a communication device. [Background technology]

[0002] For example, antenna devices are used in communication devices, etc. Improvement of the characteristics of antenna devices is desired. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2019 / 102869 Summary of the Invention [Problem to be solved by the invention]

[0004] The embodiments of the present invention provide an antenna device and a communication device that can improve characteristics. [Means for solving the problem]

[0005] According to an embodiment of the present invention, an antenna apparatus includes a plurality of left phase shifters, a plurality of right phase shifters, and a plurality of antennas. The plurality of left phase shifters include a first left phase shifter and a second left phase shifter. The first left phase shifter is configured to discretely control a first left phase of a first left-handed circularly polarized signal. The second left phase shifter is configured to discretely control a second left phase of a second left-handed circularly polarized signal. The plurality of right phase shifters include a first right phase shifter and a second right phase shifter. The first right phase shifter is configured to discretely control a first right phase of a first right-handed circularly polarized signal. The second right phase shifter is configured to discretely control a second right-handed phase of a second right-handed circularly polarized signal. The plurality of antennas include a first antenna and a second antenna. The first left phase shifter is configured to supply the first left-handed circularly polarized signal to the first antenna. The first right-hand phase shifter is configured to supply the first right-hand circularly polarized signal to the first antenna. The first antenna is configured to transmit a first left-hand circularly polarized wave based on the first left-hand circularly polarized signal and a first right-hand circularly polarized wave based on the first right-hand circularly polarized signal. The second left-hand phase shifter is configured to supply the second left-hand circularly polarized signal to the second antenna. The second right-hand phase shifter is configured to supply the second right-hand circularly polarized signal to the second antenna. The second antenna is configured to transmit a second left-hand circularly polarized wave based on the second left-hand circularly polarized signal and a second right-hand circularly polarized wave based on the second right-hand circularly polarized signal. A first polarization angle of a first linear polarization generated by the first left-hand circularly polarized wave and the first right-hand circularly polarized wave is different from a second polarization angle of a second linear polarization generated by the second left-hand circularly polarized wave and the second right-hand circularly polarized wave. [Brief explanation of the drawings]

[0006] [Figure 1] FIG. 1 is a schematic diagram illustrating an antenna device according to a first embodiment. [Figure 2] FIG. 2 is a schematic diagram illustrating a part of the antenna device according to the first embodiment. [Figure 3] FIG. 3 is a schematic diagram illustrating a part of the antenna device according to the first embodiment. [Figure 4]FIG. 4 is a schematic diagram illustrating the antenna device according to the first embodiment. [Figure 5] FIG. 5 is a schematic diagram illustrating the antenna device according to the first embodiment. [Figure 6A] FIG. 6A is a schematic diagram illustrating the antenna device according to the first embodiment. [Figure 6B] FIG. 6B is a schematic diagram illustrating the antenna device according to the first embodiment. [Figure 6C] FIG. 6C is a schematic diagram illustrating the antenna device according to the first embodiment. [Figure 7] FIG. 7 is a schematic diagram illustrating the antenna device according to the first embodiment. [Figure 8] FIG. 8 is a graph illustrating the characteristics of the antenna device according to the first embodiment. [Figure 9A] FIG. 9A is a schematic diagram illustrating the antenna device according to the first embodiment. [Figure 9B] FIG. 9B is a schematic diagram illustrating the antenna device according to the first embodiment. [Figure 10] FIG. 10 is a schematic diagram illustrating an antenna device according to the second embodiment. [Figure 11A] FIG. 11A is a graph illustrating the characteristics of the antenna device. [Figure 11B] FIG. 11B is a graph illustrating the characteristics of the antenna device. [Figure 12] FIG. 12 is a schematic diagram illustrating an antenna device according to the second embodiment. [Figure 13A] FIG. 13A is a graph illustrating the characteristics of the antenna device according to the second embodiment. [Figure 13B] FIG. 13B is a graph illustrating the characteristics of the antenna device according to the second embodiment. [Figure 14A] FIG. 14A is a schematic view illustrating the antenna device according to the second embodiment. [Figure 14B] FIG. 14B is a schematic view illustrating the antenna device according to the second embodiment. [Figure 15A]FIG. 15A is a schematic view illustrating the antenna device according to the second embodiment. [Figure 15B] FIG. 15B is a schematic view illustrating the antenna device according to the second embodiment. [Figure 16A] FIG. 16A is a schematic view illustrating the antenna device according to the second embodiment. [Figure 16B] FIG. 16B is a schematic view illustrating the antenna device according to the second embodiment. [Figure 17] FIG. 17 is a graph illustrating the characteristics of the antenna device according to the second embodiment. [Figure 18] FIG. 18 is a schematic diagram illustrating the antenna device according to the second embodiment. [Figure 19A] FIG. 19A is a graph illustrating the characteristics of the antenna apparatus according to the second embodiment. [Figure 19B] FIG. 19B is a graph illustrating the characteristics of the antenna device according to the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0007] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. The drawings are schematic or conceptual, and the relationship between the thickness and width of each part, the size ratio between parts, etc. are not necessarily the same as those in reality. Even when the same part is shown, the dimensions and ratios may be different depending on the drawing. In this specification and in each drawing, elements similar to those previously described with reference to the previous drawings are designated by the same reference numerals, and detailed descriptions thereof will be omitted where appropriate. In the following description, the x-axis, y-axis, and z-axis represent axes that are perpendicular to each other.

[0008] (First embodiment) FIG. 1 is a schematic diagram illustrating an antenna device according to a first embodiment. 2 and 3 are schematic diagrams illustrating a part of the antenna device according to the first embodiment. FIG. 4 is a schematic diagram illustrating the antenna device according to the first embodiment. FIG. 5 is a schematic diagram illustrating the antenna device according to the first embodiment. 6A to 6C are schematic views illustrating the antenna device according to the first embodiment. FIG. 7 is a schematic diagram illustrating the antenna device according to the first embodiment.

[0009] The antenna device 100 according to the embodiment can transmit left-handed circularly polarized waves and right-handed circularly polarized waves, or can receive left-handed circularly polarized waves and right-handed circularly polarized waves.

[0010] A high-frequency signal representing a left-handed circularly polarized wave is referred to as a left-handed circularly polarized signal. A high-frequency signal representing a right-handed circularly polarized wave is referred to as a right-handed circularly polarized signal. Antenna device 100 is configured to control the amplitude of the left-handed circularly polarized signal and the phase of the left-handed circularly polarized signal. Antenna device 100 is configured to control the amplitude of the right-handed circularly polarized signal and the phase of the right-handed circularly polarized signal.

[0011] For example, the antenna device 100 can transmit linearly polarized waves by simultaneously transmitting left-handed circularly polarized waves and right-handed circularly polarized waves. For example, the antenna device 100 can receive linearly polarized waves by simultaneously receiving left-handed circularly polarized waves and right-handed circularly polarized waves.

[0012] The antenna device 100 includes a phase shifter. The phase shifter controls the phase of the left-handed circularly polarized signal and the right-handed circularly polarized signal. The antenna device 100 includes, for example, a signal processing circuit 110. The signal processing circuit 110 is, for example, a beamforming circuit. The signal processing circuit 110 controls the amplitude of the left-handed circularly polarized signal and the amplitude of the right-handed circularly polarized signal. By controlling the phase shift amount of the phase shifter, the antenna device 100 controls the polarization angle of the linearly polarized wave to be transmitted. By controlling the phase shift amount of the phase shifter, the antenna device 100 controls the polarization angle of the linearly polarized wave to be received. When the antenna device 100 is a receiving antenna device, the signal processing circuit 110 is, for example, a power combiner.

[0013] In the embodiment, "transmission and reception" corresponds to "at least one of transmission and reception."

[0014] 4 illustrates the polarization plane and polarization angle τ of radio waves transmitted and received by the antenna device 100. r hat represents the symbol r with a hat attached. θ hat represents the symbol θ with a hat attached. φ hat represents the symbol φ with a hat attached.

[0015] The r-axis, θ-axis, and φ-axis are perpendicular to one another. For the r-axis, the direction away from the origin shown in FIG. 4 is defined as positive. The r-axis coincides with the beam direction 200 of the antenna device 100. The beam direction is represented by θ and φ. θ is an angle. φ is an angle.

[0016] When the antenna device 100 transmits radio waves, the beam direction corresponds to the transmitting direction of the radio waves. When the antenna device 100 receives radio waves, the beam direction corresponds to the receiving direction of the radio waves.

[0017] The polarization plane represents the vibration direction of the electric field of linearly polarized waves transmitted and received by one of the multiple antennas 11T (see FIG. 1) included in the antenna device 100. In elliptically polarized waves, the polarization plane is defined as the major axis direction of the elliptically polarized waves. In the embodiment, the linearly polarized waves include elliptical polarization. The polarization angle corresponds to the angle between the polarization plane of the linearly polarized waves and the θ hat axis. In FIG. 4, the polarization angle is represented by τ.

[0018] The antenna device 100 complies with, for example, a wireless communication standard or a wireless local area network (LAN) standard. The wireless communication standard includes, for example, a fifth generation mobile communication system (so-called 5G) or Bluetooth (registered trademark). The wireless LAN standard includes, for example, IEEE802.11ax.

[0019] The antenna device 100 may be compatible with radar or wireless power supply technology. Radar uses frequency bands such as the 9 GHz band, 24 GHz band, or 76 GHz band. Wireless power supply technology uses microwaves, etc.

[0020] The antenna device 100 may be configured to transmit and receive radio waves in, for example, the UHF band, the SHF band, or the EHF band. In the UHF (Ultra-High Frequency) band, the frequency is 300 MHz or more and 3 GHz or less. In the SHF (Super High Frequency) band, the frequency is 3 GHz or more and 30 GHz or less. In the EHF (Extremely High Frequency) band, the frequency is 30 GHz or more and 300 GHz or less.

[0021] 1, the antenna device 100 includes, for example, a plurality of antennas 11T, a plurality of left phase shifters 12L, and a plurality of right phase shifters 12R. The number of the plurality of antennas 11T is N, where N is an integer equal to or greater than 2. The number of the plurality of left phase shifters 12L may be N. The number of the plurality of right phase shifters 12R may be N.

[0022] The plurality of antennas 11T includes, for example, a first antenna 11a1, a second antenna 11a2, and an Nth antenna 11aN. The plurality of left phase shifters 12L includes, for example, a first left phase shifter 12a1, a second left phase shifter 12a2, and an Nth left phase shifter 12aN. The plurality of right phase shifters 12R includes, for example, a first right phase shifter 12b1, a second right phase shifter 12b2, and an Nth right phase shifter 12bN.

[0023] The antenna device 100 may further include, for example, a plurality of left transmission lines 13L and a plurality of right transmission lines 13R. The number of the plurality of left transmission lines 13L may be N. The number of the plurality of right transmission lines 13R is N. The plurality of left transmission lines 13L include, for example, a first left transmission line 13a1, a second left transmission line 13a2, and an Nth left transmission line 13aN. The plurality of right transmission lines 13R include, for example, a first right transmission line 13b1, a second right transmission line 13b2, and an Nth right transmission line 13bN.

[0024] For example, one of the plurality of left phase shifters 12L and one of the plurality of right phase shifters 12R are coupled to one of the plurality of antennas 11T.

[0025] The n-th left phase shifter 12an is coupled to the n-th antenna 11an by the n-th left transmission line 13an. The n-th right phase shifter 12bn is coupled to the n-th antenna 11an by the n-th right transmission line 13bn. "n" is an integer between 1 and N.

[0026] The plurality of left phase shifters 12L and the plurality of right phase shifters 12R are coupled to the signal processing circuit 110. The antenna device 100 includes, for example, a plurality of left lines 14L and a plurality of right lines 14R. The number of the plurality of left phase shifters 12L is N. The number of the plurality of right phase shifters 12R is N. The plurality of left lines 14L include, for example, a first left line 14a1, a second left line 14a2, and an Nth left line 14aN. The plurality of right lines 14R include, for example, a first right line 14b1, a second right line 14b2, and an Nth right line 14bN.

[0027] For example, the n-th left phase shifter 12an is coupled to the signal processing circuit 110 by the n-th left line 14an. The n-th right phase shifter 12bn is coupled to the signal processing circuit 110 by the n-th right line 14bn.

[0028] The antenna device 100 may include, for example, a control circuit 115, a plurality of left signal lines 16L, and a plurality of right signal lines 16R. The control circuit 115 is coupled to the signal processing circuit 110. One of the plurality of left phase shifters 12L is coupled to the control circuit 115 by one of the plurality of left signal lines 16L. One of the plurality of right phase shifters 12R is coupled to the control circuit 115 by one of the plurality of right signal lines 16R.

[0029] The left signal lines 16L include, for example, a first left signal line 16a1, a second left signal line 16a2, and an N-th left signal line 16aN. The right signal lines 16R include, for example, a first right signal line 16b1, a second right signal line 16b2, and an N-th right signal line 16bN. For example, the n-th left phase shifter 12an is coupled to the control circuit 115 by the n-th left signal line 16an. For example, the n-th right phase shifter 12bn is coupled to the control circuit 115 by the n-th right signal line 16bn.

[0030] The antenna device 100 includes, for example, a feed point 120 and a transmission line 121. The signal processing circuit 110 is coupled to the feed point 120 by the transmission line 121.

[0031] The antenna device 100 controls the phases of left-handed circularly polarized waves and right-handed circularly polarized waves transmitted and received by the multiple antennas 11T, thereby enabling the antenna device 100 to control the beam directions of the left-handed circularly polarized waves and right-handed circularly polarized waves.

[0032] One of the left phase shifters 12L can control the phase of a left-handed circularly polarized signal that indicates a left-handed circularly polarized wave transmitted and received by one of the antennas 11T. One of the right phase shifters 12R can control the phase of a right-handed circularly polarized signal that indicates a right-handed circularly polarized wave that is transmitted and received by one of the antennas 11T.

[0033] In an embodiment, the phase of the left-handed circularly polarized wave is the same as the phase of the left-handed circularly polarized signal. In an embodiment, the phase of the right-handed circularly polarized wave is the same as the phase of the right-handed circularly polarized signal.

[0034] The multiple antennas 11T can be any antennas capable of transmitting and receiving right-handed circularly polarized waves and left-handed circularly polarized waves. In Fig. 1, the multiple antennas 11T are patch antennas using degenerate separation elements. Figs. 2 and 3 show examples different from the example in Fig. 1.

[0035] 2, one of the antennas 11T includes a left radiating element 130a and a right radiating element 130b. The left radiating element 130a is capable of transmitting and receiving left-handed circularly polarized waves. The right radiating element 130b is capable of transmitting and receiving right-handed circularly polarized waves.

[0036] For example, in the example shown in FIG. 3 , one of the multiple antennas 11T includes a radiating element 131 and an external circuit 132. The radiating element 131 is capable of transmitting and receiving orthogonal linearly polarized waves. The external circuit 132 is connected to the radiating element 131. The external circuit 132 is, for example, a 90-degree hybrid circuit. The external circuit 132 is, for example, capable of generating a right-handed circularly polarized signal and a left-handed circularly polarized signal from a high-frequency signal indicating linear polarization input to the external circuit 132. Hereinafter, the high-frequency signal indicating linear polarization input to the external circuit 132 will be referred to as a “linearly polarized signal.” The external circuit 132 is, for example, capable of generating a linearly polarized signal from a right-handed circularly polarized signal and a left-handed circularly polarized signal input to the external circuit 132. By providing the external circuit 132, the radiating element 131 is capable of transmitting and receiving right-handed circularly polarized waves and left-handed circularly polarized waves.

[0037] For example, the multiple antennas 11T may have any configuration capable of transmitting and receiving right-handed circularly polarized waves and left-handed circularly polarized waves. The multiple antennas 11T may be at least one selected from the group consisting of a patch antenna, a dipole antenna, a helical antenna, a slot antenna, and a lens antenna. The multiple antennas 11T may be an antenna using a metamaterial. The multiple antennas 11T may also include an antenna that combines different types of antennas.

[0038] The left phase shifters 12L and the right phase shifters 12R may be, for example, digital phase shifters that can discretely switch the phase shift amount. The left phase shifters 12L and the right phase shifters 12R may include, for example, MEMS phase shifters. In a MEMS phase shifter, the line length can be switched using a MEMS switch. The left phase shifters 12L and the right phase shifters 12R may be, for example, reflective phase shifters. The reflective phase shifter includes, for example, a variable impedance element such as a variable capacitance diode, a transmission line whose line length can be switched, and a 90-degree hybrid circuit. The left phase shifters 12L and the right phase shifters 12R may be, for example, digital phase shifters. In a digital phase shifter, multiple digital phase shifters of different types may be combined. For example, any digital phase shifter capable of discretely switching the amount of phase shift may be applied to the plurality of left phase shifters 12L and the plurality of right phase shifters 12R.

[0039] Compared to analog phase shifters, which can continuously change the phase shift amount, digital phase shifters can be made smaller and have shorter phase switching times. On the other hand, the phase shift amount in digital phase shifters is limited to discrete values. The phase shift amount of a digital phase shifter is generally expressed using the number of bits, Nb. The phase shift amount of an Nb-bit phase shifter is substantially an integer multiple of 360° / (2^Nb). For example, in a 4-bit phase shifter, the phase shift amount is substantially an integer multiple of 360° / (2^4) = 22.5°. In a 6-bit phase shifter, the phase shift amount is substantially an integer multiple of 360° / (2^6) = 5.625°.

[0040] In a digital phase shifter, if the number of bits Nb is large, the amount of phase shift can be controlled precisely. Generally, as the number of bits Nb of a phase shifter increases, the configuration of the phase shifter becomes more complex. For example, as the number of bits Nb increases, the price of the phase shifter increases.

[0041] The left phase shifters 12L and the right phase shifters 12R may include, for example, digital phase shifters all having the same number of bits. The left phase shifters 12L and the right phase shifters 12R may include digital phase shifters having different numbers of bits. For example, the number of bits in one of the left phase shifters 12L may be different from the number of bits in another of the left phase shifters 12L. For example, the number of bits in one of the right phase shifters 12R may be different from the number of bits in another of the right phase shifters 12R.

[0042] The plurality of left transmission lines 13L, the plurality of right transmission lines 13R, the plurality of left lines 14L, the plurality of right lines 14R, and the transmission line 121 are capable of transmitting high-frequency signals. At least one of these lines may include, for example, at least one selected from the group consisting of a microstrip line, a coplanar line, a waveguide, and a coaxial cable. At least one of these lines may transmit high-frequency signals contactlessly, for example, by electromagnetic coupling. At least one of these lines may transmit high-frequency signals contactlessly, for example, by transmitting and receiving radio waves.

[0043] The left signal lines 16L and the right signal lines 16R may include at least one selected from the group consisting of, for example, electric wires, microstrip lines, coplanar lines, waveguides, and coaxial cables. The left signal lines 16L and the right signal lines 16R may transmit signals non-contactly by electromagnetic coupling. The left signal lines 16L and the right signal lines 16R may transmit signals non-contactly by transmitting and receiving radio waves. Any configuration capable of transmitting electrical signals may be applied to the left signal lines 16L and the right signal lines 16R.

[0044] The electrical signals transmitted by the left signal lines 16L and the right signal lines 16R may include at least one selected from the group consisting of a high frequency signal, a direct current signal, and a low frequency signal.

[0045] A signal is input to the signal processing circuit 110 from the feeding point 120 via the transmission line 121. For example, when the antenna device 100 transmits radio waves, the signal processing circuit 110 controls the amplitude of the signal input to the signal processing circuit 110 and distributes the signal to the multiple left phase shifters 12L and the multiple right phase shifters 12R. Use of the signal processing circuit 110 makes it possible to control the amplitude of the left-handed circularly polarized waves and the right-handed circularly polarized waves transmitted from the multiple antennas 11T.

[0046] The signal processing circuit 110 distributes the signals so that, for example, the amplitude of the left-handed circularly polarized signal supplied to the nth left phase shifter 12an and the amplitude of the right-handed circularly polarized signal supplied to the nth right phase shifter 12bn are substantially equal to each other.

[0047] The amplitude of the left-handed circularly polarized signal that the signal processing circuit 110 outputs to the n-th left phase shifter 12an may be different from the amplitude of the left-handed circularly polarized signal that the signal processing circuit 110 outputs to the m-th left phase shifter 12am, where "m" is an integer between 1 and N, inclusive, and is different from "n."

[0048] The amplitude of the right-handed circularly polarized signal that the signal processing circuit 110 outputs to the n-th right phase shifter 12bn may be different from the amplitude of the right-handed circularly polarized signal that the signal processing circuit 110 outputs to the m-th right phase shifter 12bm.

[0049] For example, when antenna device 100 receives radio waves, signal processing circuit 110 controls the amplitudes of left-handed circularly polarized signals and right-handed circularly polarized signals output from multiple antennas 11T and combines them. Signal processing circuit 110 outputs the combined signal to feed point 120 via transmission line 121. By using signal processing circuit 110, antenna device 100 can change the amplitudes of left-handed circularly polarized waves and right-handed circularly polarized waves received by multiple antennas 11T and combine them.

[0050] Any configuration capable of distributing or synthesizing high-frequency signals can be provided for the signal processing circuit 110. The signal processing circuit 110 may include, for example, at least one of an analog circuit and a digital circuit.

[0051] The control circuit 115 may include, for example, at least one of a central processing unit (CPU), a digital signal processor (DSP), a microcomputer, and an FPGA (Field Programmable Gate Array).

[0052] The control circuit 115 controls, for example, the left phase shifters 12L, the right phase shifters 12R, and the signal processing circuit 110. The control circuit 115 transmits and receives control signals via the left signal lines 16L to control the left phase shifters 12L. The control circuit 115 transmits and receives control signals via the right signal lines 16R to control the right phase shifters 12R.

[0053] For example, when the antenna device 100 transmits radio waves, the control circuit 115 controls the phase shift amounts of the plurality of left phase shifters 12L, the phase shift amounts of the plurality of right phase shifters 12R, the amplitude of the right-handed circularly polarized signal output by the signal processing circuit 110, and the amplitude of the left-handed circularly polarized signal output by the signal processing circuit 110.

[0054] The control circuit 115, for example, controls the amplitude of the left-handed circularly polarized signal that the signal processing circuit 110 outputs to the plurality of left lines 14L. The control circuit 115, for example, controls the amplitude of the right-handed circularly polarized signal that the signal processing circuit 110 outputs to the plurality of right lines 14R. When a left-handed circularly polarized signal is input, the plurality of antennas 11T transmits a left-handed circularly polarized wave. When a right-handed circularly polarized signal is input, the plurality of antennas 11T transmits a right-handed circularly polarized wave.

[0055] When left-handed and right-handed circularly polarized signals are input, the antennas 11T transmit linearly polarized waves. The amplitude of the left-handed circularly polarized signal is substantially the same as the amplitude of the right-handed circularly polarized signal. The frequency band of the left-handed circularly polarized signal is substantially the same as the frequency band of the right-handed circularly polarized signal.

[0056] The control circuit 115 controls the phase shift amounts of the multiple left phase shifters 12L and the multiple right phase shifters 12R, thereby controlling the polarization angle and beam direction of the linearly polarized wave transmitted by the antenna device 100.

[0057] When antenna device 100 receives radio waves, control circuit 115 controls the phase shift amounts of the multiple left phase shifters 12L, the phase shift amounts of the multiple right phase shifters 12R, the amplitude of the left-handed circularly polarized signal input to signal processing circuit 110, and the amplitude of the right-handed circularly polarized signal input to signal processing circuit 110. By controlling the phase shift amounts, control circuit 115 controls the phase shift amounts of left-handed circularly polarized signals corresponding to left-handed circularly polarized waves input from the multiple antennas 11T to the multiple left phase shifters 12L. By controlling the phase shift amounts, control circuit 115 controls the phase shift amounts of right-handed circularly polarized signals corresponding to right-handed circularly polarized waves input from the multiple antennas 11T to the multiple right phase shifters 12R.

[0058] The control circuit 115 controls the amplitude of the left-handed circularly polarized signals input to the signal processing circuit 110 from the multiple left lines 14L. The control circuit 115 controls the amplitude of the right-handed circularly polarized signals input to the signal processing circuit 110 from the multiple right lines 14R. When the multiple antennas 11T receive left-handed circularly polarized waves, left-handed circularly polarized signals are output. When the multiple antennas 11T receive right-handed circularly polarized waves, right-handed circularly polarized signals are output. When the multiple antennas 11T receive linearly polarized waves, left-handed circularly polarized signals and right-handed circularly polarized signals are output. The frequency band of the left-handed circularly polarized signals is substantially equal to the frequency band of the left-handed circularly polarized signals.

[0059] The control circuit 115 controls the phase shift amounts of the multiple left phase shifters 12L and the multiple right phase shifters 12R, thereby enabling the control circuit 115 to control the polarization angle and beam direction of the linearly polarized wave received by the antenna device 100.

[0060] The control circuit 115 controls the left phase shifters 12L, the right phase shifters 12R, and the signal processing circuit 110, thereby controlling the linearly polarized signal output by the signal processing circuit 110.

[0061] The control circuit 115 may be coupled to a memory unit 18M (see FIG. 1). The memory unit 18M can store various types of information related to the embodiment. The various types of information include, for example, information about the amount of phase shift, the amplitude of the left-handed circularly polarized signal, the phase of the left-handed circularly polarized signal, the amplitude of the right-handed circularly polarized signal, and the phase of the right-handed circularly polarized signal.

[0062] The storage unit 18M may include, for example, at least one of a random access memory (RAM), a flash memory, and a hard disk drive (HDD). The antenna device 100 may include the storage unit 18M. The storage unit 18M may be provided separately from the antenna device 100.

[0063] An example of controlling the polarization angle in the embodiment will be described below. 5 illustrates an example of control of the polarization angle of linearly polarized waves transmitted and received by one of the multiple antennas 11T. FIG. 5 illustrates an example of the polarization angle in the beam direction of the antenna device 100. The phase of the left-handed circularly polarized wave transmitted and received by the n-th antenna 11an is controlled by an angle φ L (n) The phase of the right-handed circularly polarized wave transmitted and received by the n-th antenna 11an is set to an angle φ R (n) Let's say.

[0064] 5, the left-handed circularly polarized wave transmitted and received by the n-th antenna 11an is represented by a left-handed vector 201L. The left-handed circularly polarized wave transmitted and received by the n-th antenna 11an is represented by a right-handed vector 201R. The angle between the left-handed vector 201L and the θ hat axis is the angle φ L (n) The angle between the right vector 201R and the θ axis is the angle φ R (n) Corresponds to.

[0065] The length of the left vector 201L corresponds to the amplitude of the left-handed circularly polarized wave transmitted and received by the n-th antenna 11an. The length of the right vector 201R corresponds to the amplitude of the right-handed circularly polarized wave transmitted and received by the n-th antenna 11an. In Figure 5, the length of the left vector 201L is substantially equal to the length of the right vector 201R.

[0066] Angle φ L (n) and angle φ R (n) The difference ΔΨ (n) is defined by equation (1).

number

[0067] The polarization angle τ of the linearly polarized wave transmitted and received by the n-th antenna 11an (n) is the difference ΔΨ (n) In FIG. 5, the angle φ L (n) is 0°.

number

[0068] Angle φ L (n) is the angle φ R (n) When the angle of polarization τ of the linearly polarized wave transmitted and received by the n-th antenna 11an is equal to (n) is 0°. Angle φ L (n) and angle φ R (n) When the difference between the angles is 180°, the polarization angle τ of the linearly polarized wave transmitted and received by the n-th antenna 11an is (n) is 90°.

[0069] The polarization angle of the linearly polarized wave received by the n-th antenna 11an is τ (n) The n-th left phase shifter 12an corresponds to the n-th antenna 11an. The n-th right phase shifter 12bn corresponds to the n-th antenna 11an. τ (n) is given by equation (2) from the relative phase shift amount between the left-handed circularly polarized signal output by the n-th left phase shifter 12an and the left-handed circularly polarized signal output by the n-th right phase shifter 12bn.

[0070] The polarization angle of the linearly polarized wave arriving at the n-th antenna 11an is τ (n) does not necessarily coincide with.

[0071] The n-th left phase shifter 12an and the n-th right phase shifter 12bn are, for example, digital phase shifters that can discretely switch the phase shift amount. Therefore, the phase shift amount of the n-th left phase shifter 12an and the phase shift amount of the n-th right phase shifter 12bn are substantially limited to an integer multiple of the minimum phase shift amount α. The minimum phase shift amount α is given by equation (3) where the number of bits of the phase shifter is Nb.

number

[0072] From equation (3), the angle φ L (n) and angle φ R (n) is substantially limited to an integer multiple of the minimum phase shift amount α.

[0073] From the formulas (1) and (3), in the antenna device 100 according to the embodiment, the angle φ L (n) and angle φ R (n) The difference ΔΨ (n) is substantially limited to an integer multiple of the minimum phase shift amount α.

[0074] From the formulas (1), (2), and (3), in the antenna device 100 according to the embodiment, τ (n) is limited to a substantially integer multiple of half (α / 2) of the minimum phase shift amount α. Therefore, the polarization angle of the linearly polarized wave transmitted and received by the n-th antenna 11an is limited to a substantially integer multiple of α / 2.

[0075] In the antenna device 100 according to this embodiment, the polarization angle of the linearly polarized waves transmitted and received by each of the multiple antennas 11T is limited to a substantially integer multiple of α / 2. For example, the phase shift amounts of the multiple left phase shifters 12L and the multiple right phase shifters 12R are controlled so that the polarization angles of the linearly polarized waves transmitted and received by each of the multiple antennas 11T are substantially equal to each other. In this case, an error occurs between the desired polarization angle transmitted and received by the antenna device 100 and the polarization angle actually transmitted and received. This error is maximized when the desired polarization angle is the intermediate value of a substantially integer multiple of α / 2 (i.e., α / 4+Aα / 2, where A is an arbitrary integer). For example, the maximum value of the polarization angle error is α / 4.

[0076] For example, when the left phase shifters 12L and the right phase shifters 12R are 4-bit phase shifters, the minimum phase shift amount is 22.5° from equation (3). In this case, the polarization angle of the linearly polarized wave transmitted and received by the antenna device 100 is limited to a substantial integral multiple of 11.25°. The error between the intended polarization angle transmitted and received by the antenna device 100 and the polarization angle actually transmitted and received is a maximum of 5.625°.

[0077] If an error occurs between the polarization angle that the antenna device 100 aims to transmit and receive and the polarization angle that is actually transmitted and received, problems such as degradation of communication quality may occur.

[0078] When wireless communication is performed using the antenna device 100, if an error occurs between the polarization angle at which the antenna device 100 is intended to transmit and receive and the polarization angle at which the antenna device 100 actually transmits and receives, for example, the cross polarization discrimination (XPD) will decrease. For example, a polarization multiplexing technique is known that multiplexes communications using two orthogonal linearly polarized waves. The polarization multiplexing technique is used in wireless communications or radar to improve frequency efficiency. In wireless communications using the polarization multiplexing technique, if radio waves with low XPD are transmitted, the radio waves will interfere with other communications, degrading communication quality. For example, when the antenna device 100 is used as a radar, a decrease in XPD will degrade the radar's detection characteristics.

[0079] The electric field amplitude of the linearly polarized wave parallel to the desired polarization angle is E Co The electric field amplitude of the linearly polarized wave that is orthogonal to the desired polarization angle is E X The XPD is defined by equation (4).

number

[0080] For example, Japan's Radio Equipment Regulations stipulate that the XPD of an antenna for a 9.7 GHz band weather radar must be 25 dB or more, and that the XPD of an antenna for a small earth station in the Ku band (12 GHz to 14 GHz) must be 27 dB or more.

[0081] Assume that the left and right phase shifters 12L and 12R are 4-bit phase shifters, and that these phase shifters are controlled so that the polarization angles of the linearly polarized waves transmitted and received by the antennas 11T are all substantially equal. In this case, when the error between the desired polarization angle and the polarization angle actually transmitted and received is maximum, XPD is approximately 20 dB. In this case, the antenna device 100 does not satisfy the above criteria and cannot be used for the above purpose.

[0082] For example, by increasing the number of bits Nb of the left phase shifters 12L and the right phase shifters 12R, it is possible to reduce errors in the polarization angles transmitted and received by the antenna device 100 and improve XPD. However, increasing the number of bits Nb of these phase shifters increases the cost of these phase shifters. Increasing the number of bits Nb of these phase shifters increases the cost of the antenna device 100.

[0083] According to the embodiments, for example, the polarization angle transmitted and received by the antenna device 100 can be controlled at intervals narrower than a substantial integral multiple of α / 2 without increasing the number of bits Nb of these phase shifters. In the embodiments, for example, the polarization angle can be controlled with high precision using a simple configuration. According to the embodiments, an antenna device capable of improving characteristics can be provided. According to the embodiments, the XPD of radio waves transmitted and received by the antenna device 100 can be improved at low cost.

[0084] In the embodiment, the polarization angles of the linearly polarized waves transmitted and received by each of the multiple antennas 11T may be different from each other. The polarization angle of the linearly polarized waves transmitted and received by each of the multiple antennas 11T is one of τ1 and τ2. τ1 is different from τ2.

[0085] For example, the phase shift amounts of the multiple left phase shifters 12L and the multiple right phase shifters 12R may be controlled individually. This allows the polarization angles of the linearly polarized waves transmitted and received by the multiple antennas 11T to be controlled individually. In this case, the polarization angles of the linearly polarized waves transmitted and received by the antenna device 100 are different from both τ1 and τ2.

[0086] 6A to 6C illustrate the relationship between the polarization angle of linearly polarized waves transmitted and received by the multiple antennas 11T and the polarization angle of linearly polarized waves transmitted by the antenna device 100. In the examples of FIGS. 6A to 6C, the polarization angles of the linearly polarized waves transmitted and received by each of the multiple antennas 11T are different from one another. In FIGS. 6A to 6C, N is 4. The multiple antennas 11T include four antennas. The four antennas include a first antenna 11a1, a second antenna 11a2, a third antenna 11a3 (not shown), and a fourth antenna 11a4 (not shown).

[0087] 6A to 6C, four vectors (vector 210a1, vector 210a2, vector 210a3, and vector 210a4) represent linearly polarized waves transmitted and received by the four antennas, respectively. Vectors 211a, vector 211b, and vector 211c represent linearly polarized waves synthesized from the linearly polarized waves transmitted and received by the four antennas, respectively.

[0088] The angles between the above four vectors and the θ-axis represent the polarization angles of the linearly polarized waves transmitted and received by each of the four antennas. The lengths of the four vectors represent the amplitudes of the linearly polarized waves transmitted and received by each of the four antennas. In the examples of FIGS. 6A to 6C, the lengths of the four vectors are substantially equal to each other. In some embodiments, the lengths of the four vectors may be different from each other.

[0089] 6A, the polarization angle of the linearly polarized waves transmitted and received by first antenna 11a1, second antenna 11a2, and third antenna 11a3 is τ1. The polarization angle of the linearly polarized waves transmitted and received by fourth antenna 11a4 is τ2. The angle between vector 211a and the θ-hat axis is τ3.

[0090] 6B, the polarization angle of the linearly polarized waves transmitted and received by each of first antenna 11a1 and second antenna 11a2 is τ1. The polarization angle of the linearly polarized waves transmitted and received by third antenna 11a3 and fourth antenna 11a4 is τ2. The angle between vector 211b and the θ-hat axis is τ4.

[0091] 6C, the polarization angle of the linearly polarized waves transmitted and received by first antenna 11a1 is τ1. The polarization angle of the linearly polarized waves transmitted and received by second antenna 11a2, third antenna 11a3, and fourth antenna 11a4 is τ2. The angle between vector 211c and the θ-axis is τ5.

[0092] 6A to 6C, the angle between vector 211a and the θ-axis, the angle between vector 211b and the θ-axis, and the angle between vector 211c and the θ-axis correspond to the polarization angles of the linearly polarized waves synthesized from the linearly polarized waves transmitted and received by the four antennas. These angles (and their polarization angles) are different from both τ1 and τ2.

[0093] 6A to 6C, the polarization angle of the linearly polarized wave transmitted and received by antenna device 100 corresponds to the polarization angle of the linearly polarized wave obtained by combining the linearly polarized waves transmitted and received by the four antennas. Therefore, in FIGS. 6A to 6C, the polarization angle of the linearly polarized wave transmitted and received by antenna device 100 is different from both τ1 and τ2.

[0094] In the example of FIGS. 6A to 6C, τ1, τ2, τ3, τ4, and τ5 satisfy the relationship of formula (5).

number

[0095] In the examples of FIGS. 6A to 6C, when the difference between τ1 and τ2 is α / 2, the polarization angle of the linearly polarized wave transmitted and received by antenna device 100 is controlled at intervals narrower than α / 2.

[0096] In the embodiment, the polarization angle of the linearly polarized wave transmitted and received by the antenna device 100 can be controlled in intervals narrower than α / 2 without increasing the number of bits Nb of the phase shifter.

[0097] Fig. 7 illustrates the relationship between the polarization angle of linearly polarized waves transmitted and received by multiple antennas 11T and the polarization angle of linearly polarized waves transmitted and received by antenna device 100. In the example of Fig. 7, the number of multiple antennas 11T is N. For example, the polarization angle of linearly polarized waves transmitted and received by (Nm) antennas 11T is τ1. The polarization angle of linearly polarized waves transmitted and received by m antennas 11T is τ2. "m" is an integer greater than or equal to 0 and less than or equal to N. τ1 is different from τ2.

[0098] In Figure 7, vector 210a represents a linearly polarized wave obtained by combining linearly polarized waves transmitted and received by (Nm) antennas 11T. Vector 210b represents a linearly polarized wave obtained by combining linearly polarized waves transmitted and received by m antennas 11T. Vector 211 represents a linearly polarized wave obtained by combining linearly polarized waves transmitted and received by N antennas 11T. The angle between vector 210a and the θ hat axis is τ1. The angle between vector 210b and the θ hat axis is τ2. The angle between vector 211 and the θ hat axis is τ0.

[0099] 7, the polarization angle of the linearly polarized waves transmitted and received by the first antenna 11a1 to the (Nm)th antenna 11a(Nm) is denoted by τ1, and the polarization angle of the linearly polarized waves transmitted and received by the (N-m+1)th antenna 11a(N-m+1) to the Nth antenna 11aN is denoted by τ2.

[0100] τ0, τ1, and τ2 satisfy the relationship of equation (6).

number

[0101] In FIG. 7, "δ" is defined by equation (7).

number

[0102] The amplitude of the linearly polarized wave transmitted and received by the k-th antenna 11ak (k is an integer between 1 and N) is defined as "a k The θ hat component Eθ1 of the vector 210a and the φ hat component Eφ1 of the vector 210a are expressed by equation (8).

number

[0103] The θ component Eθ1 of the vector 210b and the φ component Eφ2 of the vector 210b are expressed by equation (9).

number

[0104] In this case, the relationship of equation (10) holds for the polarization angle τ0.

number

[0105] The polarization angle of the linearly polarized wave that is intended to be transmitted and received by the antenna device 100 is set to τ0. The polarization angles of the linearly polarized waves that are transmitted and received by the multiple antennas 11T are set to either τ1 or τ2. In this case, by solving equation (10) for "m," the polarization angle of the linearly polarized wave that is transmitted and received by each of the multiple antennas 11T can be determined.

[0106] The control circuit 115 determines either τ1 or τ2 for the polarization angle of each of the multiple antennas 11T based on, for example, "m" obtained by solving equation (10). The control circuit 115 controls the phase shift amounts of the multiple left phase shifters 12L and the multiple right phase shifters based on, for example, the determination.

[0107] For example, assume that the amplitude of the linearly polarized waves transmitted and received by the multiple antennas 11T is 1. In this case, the length of vector 210a is (Nm). The length of vector 210b is m. In this case, equation (10) can be transformed to obtain equation (11).

number

[0108] By solving equation (11) for m, equation (12) is obtained.

number

[0109] By transforming equation (12), equation (13) is obtained.

number

[0110] By substituting equation (7) into equation (13), equation (14) is obtained.

number

[0111] Equation (14) can be transformed to obtain equation (15).

number

[0112] Here, we assume that "δ" (unit: radian) is sufficiently smaller than 1, and ignore the second-order infinitesimal terms. As an approximation of equation (15), we obtain equation (16).

number

[0113] If the second-order infinitesimal term in equation (16) is ignored, equation (17) is obtained as an approximation of equation (16).

[0114]

number

number

[0115] When "δ" is equal to half the minimum phase shift, α / 2, equation (19) is obtained from equation (18).

number

[0116] When "δ" is equal to half the minimum phase shift (α / 2), the difference between τ0 and τ1 is equal to or less than α / 2 according to the relationship in equation (6). When the minimum phase shift α (in radians) is sufficiently smaller than 1, equation (20) is obtained as an approximation of equation (19).

number

[0117] Solving equation (20) for τ0 gives equation (21).

number

[0118] When equation (20) is satisfied, the polarization angle of the waves transmitted and received by antenna device 100 is variable substantially by an integer multiple of α / (2N) according to equation (21).

[0119] When "δ" is sufficiently smaller than 1 and N is sufficiently large, the polarization angle of the linearly polarized wave transmitted and received by the antenna device 100 becomes substantially continuously variable.

[0120] For example, suppose the number of bits Nb of the multiple left phase shifters 12L and the multiple right phase shifters 12R is 6. The number of multiple antennas 11T (i.e., N) is 1,000. In this case, α is 360° / (2^6)=5.625°. That is, α is approximately 0.098 radians, which is sufficiently smaller than 1. From equation (21), τ0 is variable at intervals of approximately 0.0028125°.

[0121] In this case, the maximum error between the target polarization angle and the polarization angle of the linearly polarized wave transmitted and received by the antenna device 100 is approximately α / (4N) (approximately 0.00140625°). Co is cos(0.00140625°). E in Eq. (4) X is sin(0.00140625°). From equation (4), the minimum value of XPD is approximately 92 dB.

[0122] For example, the number of bits Nb of the left phase shifters 12L and the right phase shifters 12R is 6, and the antennas 11T are controlled to transmit and receive linearly polarized waves with substantially the same polarization angle. In this case, from equation (4), the minimum value of XPD is approximately 26 dB.

[0123] In the embodiment, the antenna device 100 transmits and receives linearly polarized waves by combining right-handed circularly polarized waves and left-handed circularly polarized waves. In the antenna device 100, the polarization angle of the linearly polarized waves transmitted and received by the antenna device 100 can be controlled at intervals narrower than, for example, half the minimum phase shift amount α (α / 2) without increasing the number of bits Nb of the left phase shifters 12L and the right phase shifters.

[0124] According to the embodiment, for example, the error between the polarization angle of the desired linearly polarized wave transmitted and received by the antenna device 100 and the polarization angle of the linearly polarized wave actually transmitted and received by the antenna device 100 is reduced.

[0125] According to the embodiment, for example, it is possible to use a digital phase shifter with a small number of bits Nb to finely adjust the polarization angle of the linearly polarized wave transmitted and received by the antenna device 100. A low-cost antenna device 100 can be provided.

[0126] In the embodiment, when the antenna device 100 is a transmitting antenna, the following configuration may be applied: The plurality of left phase shifters 12L includes a first left phase shifter 12a1 and a second left phase shifter 12a2 (see FIG. 1). The first left phase shifter 12a1 is configured to discretely control the first left phase of the first left-handed circularly polarized signal SL1 (see FIG. 1). The second left phase shifter 12a2 is configured to discretely control the second left phase of the second left-handed circularly polarized signal SL2 (see FIG. 1).

[0127] In the embodiment, the plurality of right phase shifters 12R includes a first right phase shifter 12b1 and a second right phase shifter 12b2 (see FIG. 1). The first right phase shifter 12b1 is configured to discretely control the first right phase of the first right-handed circularly polarized signal SR1 (see FIG. 1). The second right phase shifter 12b2 is configured to discretely control the second right phase of the second right-handed circularly polarized signal SR2 (see FIG. 1).

[0128] In the embodiment, the multiple antennas 11T include a first antenna 11a1 and a second antenna 11a2 (see FIG. 1). For example, the first left phase shifter 12a1 is configured to supply a first left-handed circularly polarized signal SL1 to the first antenna 11a1. The first right phase shifter 12b1 is configured to supply a first right-handed circularly polarized signal SR1 to the first antenna 11a1. For example, the first antenna 11a1 is configured to transmit a first left-handed circularly polarized wave based on the first left-handed circularly polarized signal SL1 and a first right-handed circularly polarized wave based on the first right-handed circularly polarized signal SR1.

[0129] For example, the second left phase shifter 12a2 is configured to supply a second left-handed circularly polarized signal SL2 to the second antenna 11a2. The second right phase shifter 12b2 is configured to supply a second right-handed circularly polarized signal SR2 to the second antenna 11a2. For example, the second antenna 11a2 is configured to transmit a second left-handed circularly polarized wave based on the second left-handed circularly polarized signal SL2 and a second right-handed circularly polarized wave based on the second right-handed circularly polarized signal SR2.

[0130] In the embodiment, a first polarization angle (e.g., τ1) of a first linearly polarized wave generated by the first left-handed circularly polarized wave and the first right-handed circularly polarized wave is different from a second polarization angle (e.g., τ2) of a second linearly polarized wave generated by the second left-handed circularly polarized wave and the second right-handed circularly polarized wave. For example, the polarization angle of the linearly polarized wave transmitted by the antenna device 100 can be finely adjusted. According to the embodiment, an antenna device capable of improving characteristics can be provided.

[0131] In the embodiment, for example, the Nth left phase shifter 12aN is configured to discretely control the Nth left phase of the Nth left-handed circularly polarized signal SLN (see FIG. 1). For example, the Nth right phase shifter 12bN is configured to discretely control the Nth right phase of the Nth right-handed circularly polarized signal SRN. For example, the Nth left phase shifter 12aN is configured to supply the Nth left-handed circularly polarized signal SLN to the Nth antenna 11aN. The Nth right phase shifter 12bN is configured to supply the Nth right-handed circularly polarized signal SRN to the Nth antenna 11aN. For example, the Nth antenna 11aN is configured to transmit a first left-handed circularly polarized wave based on the Nth left-handed circularly polarized signal SLN and an Nth right-handed circularly polarized wave based on the Nth right-handed circularly polarized signal SRN.

[0132] Below, some examples of controlling the polarization angle will be described. FIG. 8 is a graph illustrating the characteristics of the antenna device according to the first embodiment. FIG. 8 shows the relationship between the polarization angle PA of the linearly polarized wave received by the antenna device 100 and the received power Pr.

[0133] Generally, when the antenna device 100 receives linearly polarized waves for communication, the control circuit 115 controls the N left phase shifters 12L, the N right phase shifters 12R, and the signal processing circuit 110 so that the received power Pr is maximized when the antenna device 100 receives a linearly polarized wave signal. When the received power Pr is large, the signal-to-noise ratio increases, and therefore the communication quality improves.

[0134] On the other hand, the antenna device 100 may be used as a radar that detects linearly polarized waves received by the antenna device 100. In this case, the antenna device 100 may be controlled so that the received power Pr is minimized when the antenna device 100 receives a linearly polarized signal arriving at the antenna device 100.

[0135] Known methods for estimating radio waves arriving at the antenna device 100 include peak search technology and null search technology. In the peak search technology, a point where the radiation directivity is maximum is scanned, and the beam direction where the received power Pr is maximum is estimated as the direction of arrival of the radio waves. In the null search technology, a point where the radiation directivity is minimum (null point) is scanned, and the beam direction where the received power Pr is minimum is estimated as the direction of arrival of the radio waves. Known null search technology includes, for example, the MUSIC (Multiple Signal Classification) method.

[0136] In null search, the fluctuation of the received power Pr near the beam direction is larger than in peak search, and the estimation accuracy of the direction of arrival of the radio wave is higher.

[0137] Fig. 8 shows the relationship between the polarization angle PA and the received power Pr of the linearly polarized wave received by antenna device 100. Fig. 8 shows an example of the relationship between the polarization angle PA and the received power Pr when the beam direction is fixed and the polarization angle PA of the linearly polarized wave received is rotated in antenna device 100. In Fig. 8, the polarization angle PA of the linearly polarized wave arriving at antenna device 100 is denoted by τ.

[0138] 8, the received power Pr of the antenna device 100 is maximum when the polarization angle PA of the received waves by the antenna device 100 is τ. The received power Pr of the antenna device 100 is minimum when the polarization angle PA of the received waves by the antenna device 100 is τ+90°. When estimating the polarization angle PA of the linearly polarized waves arriving at the antenna device 100, a null search may be applied. In this case, the polarization angle PA(τ) of the arriving linearly polarized waves can be estimated based on the polarization angle PA(τ+90°) when the received power Pr of the antenna device 100 is minimum.

[0139] In the embodiment, according to the above example, the estimation accuracy of the polarization angle PA of the linearly polarized wave arriving at the antenna device 100 can be improved by using the null search technique.

[0140] 9A and 9B are schematic views illustrating the antenna device according to the first embodiment. 9A and 9B illustrate examples of the relationship between the linearly polarized waves transmitted and received by each of the N antennas 11T included in the antenna device 100 and the polarization angles of the linearly polarized waves transmitted and received by the antenna device 100. FIG.

[0141] Vector 210a1 represents a linearly polarized wave resulting from the combination of linearly polarized waves with a polarization angle τ1 transmitted and received by (Nm) antennas 11T. Vector 210b1 represents a linearly polarized wave resulting from the combination of linearly polarized waves with a polarization angle τ2 transmitted and received by N antennas 11T. The angle between vector 210a1 and the θ hat axis is set to τ1. The angle between vector 210b1 and the θ hat axis is set to τ2. τ1 is smaller than τ2. The angle between vector 2111 and the θ hat axis is set to τ0.

[0142] The minimum phase shift amount of the phase shifter included in the antenna device 100 is defined as α. τ1 and τ2 are each substantially integer multiples of α / 2 and can be set to any value. It is preferable that the difference between τ1 and τ2 is small. Vector 2111 is generated by combining vector 210a1 and vector 210b1. Components of vector 210a1 and vector 210b1 that are orthogonal to τ0 cancel each other out. In other words, when the difference between τ1 and τ2 is small, the power transmitted and received by the antenna device 100 is large. When the difference between τ1 and τ2 is large, the power transmitted and received by the antenna device 100 is small.

[0143] The length of vector 2111 in Fig. 9A is longer than vector 2111 in Fig. 9B. If the difference between τ1 and τ2 is large, the power of the linearly polarized waves transmitted and received by antenna device 100 will decrease. The decrease in transmitted and received power will cause problems such as deterioration in communication quality. Therefore, it is preferable that the difference between τ1 and τ2 is small.

[0144] τ1 and τ2 can be set to values ​​that are substantially integer multiples of α / 2. For example, the minimum absolute value of the difference between τ1 and τ2 is α / 2. At this time, the power of the linearly polarized wave transmitted and received by the antenna device 100 is maximized.

[0145] In the embodiment, in the antenna device 100, it is preferable that the polarization angles of the linearly polarized waves transmitted and received by the multiple antennas 11T are controlled so that the absolute value of the difference between τ1 and τ2 becomes α / 2.

[0146] In the embodiment, for example, the first left phase shift amount of the first left phase shifter 12a1 is a first integer multiple of the first minimum phase shift amount. For example, the first right phase shift amount of the first right phase shifter 12b1 is a second integer multiple of the second minimum phase shift amount. The first minimum phase shift amount is substantially the same as the second minimum phase shift amount. The first minimum phase shift amount and the second minimum phase shift amount are substantially the above-mentioned minimum phase shift amount α. In the embodiment, for example, the absolute value of the difference between the first polarization angle (e.g., τ1) and the second polarization angle (e.g., τ2) is, for example, 0.45 to 0.55 times the first minimum phase shift amount. The absolute value of the difference may be, for example, 0.45 to 0.55 times the second minimum phase shift amount. For example, power loss can be suppressed.

[0147] For example, the antenna device 100 may include an Nb-bit phase shifter and an Mb-bit phase shifter, where Nb is different from Mb. The antenna device 100 includes N antennas 11T. For example, (Nm) antennas 11T are coupled to Nb-bit left phase shifters and Nb-bit right phase shifters. The (Nm) antennas 11T transmit and receive linearly polarized waves with a polarization angle τ1. For example, m antennas 11T are coupled to Mb-bit left phase shifters and Mb-bit right phase shifters. The m antennas 11T transmit and receive linearly polarized waves with a polarization angle τ2.

[0148] It is preferable that the difference between τ1 and τ2 is small. For example, τ1 is controlled to be substantially an integer multiple of 180° / (2^Nb). For example, τ2 is controlled to be substantially an integer multiple of 180° / (2^Mb). For example, the absolute value of the difference between τ1 and τ2 may be half or less of the larger value of 180° / (2^Nb) and 180° / (2^Mb). At this time, the amount of cancellation of the component of the transmitted and received power that is orthogonal to τ0 is minimized.

[0149] In an embodiment, it is preferable that the polarization angles of the multiple antennas 11T are controlled so that the absolute value of the difference between τ1 and τ2 is less than half the larger of 180° / (2^Nb) and 180° / (2^Mb).

[0150] In the embodiment, the first left phase shift amount of the first left phase shifter 12a1 is a first integer multiple of the first minimum phase shift amount. The first right phase shift amount of the first right phase shifter 12b1 is a second integer multiple of the second minimum phase shift amount. The first minimum phase shift amount is greater than the second minimum phase shift amount. In the embodiment, the difference between the first polarization angle and the second polarization angle is 0.55 times or less of the first minimum phase shift amount. For example, power loss can be suppressed.

[0151] In the embodiment, when the antenna device 100 is a transmitting antenna, the following configuration may be applied. The multiple antennas 11T include a first antenna 11a1 and a second antenna 11a2. The first antenna 11a1 is configured to receive left-handed circularly polarized waves and right-handed circularly polarized waves and output a first left-handed circularly polarized signal SL1 and a first right-handed circularly polarized signal SR1 (see FIG. 1). The second antenna 11a2 is configured to receive left-handed circularly polarized waves and right-handed circularly polarized waves and output a second left-handed circularly polarized signal SL2 and a second right-handed circularly polarized signal SR2 (see FIG. 1).

[0152] The plurality of left phase shifters 12L includes a first left phase shifter 12a1 and a second left phase shifter 12a2. The first left phase shifter 12a1 is configured to discretely control the first left phase of the first left-handed circularly polarized signal SL1. The second left phase shifter 12a2 is configured to discretely control the second left phase of the second left-handed circularly polarized signal SL2. The plurality of right phase shifters 12R includes a first right phase shifter 12b1 and a second right phase shifter 12b2. The first right phase shifter 12b1 is configured to discretely control the first right phase of the first right-handed circularly polarized signal SR1. The second right phase shifter 12b2 is configured to discretely control the second right-handed phase of the second right-handed circularly polarized signal SR2.

[0153] The signal processing circuit 110 (see FIG. 1) is configured to be coupled to the plurality of left phase shifters 12L and the plurality of right phase shifters 12R. The signal processing circuit 110 is configured to generate a linearly polarized signal indicating linear polarization from the first left-handed circularly polarized signal SL1, the first right-handed circularly polarized signal SR1, the second left-handed circularly polarized signal SL2, and the second right-handed circularly polarized signal SR2. In this case, the signal processing circuit 110 may be, for example, a power combiner.

[0154] In the embodiment, a first polarization angle (e.g., τ1) of a first linearly polarized signal generated from the first left-handed circularly polarized signal SL1 and the first right-handed circularly polarized signal SR1 is different from a second polarization angle (e.g., τ2) of a second linearly polarized signal generated from the second left-handed circularly polarized signal SL2 and the second right-handed circularly polarized signal SR2. For example, the first left phase shift amount of the first left phase shifter, the second left phase shift amount of the second left phase shifter, the first right phase shift amount of the first right phase shifter, and the second right phase shift amount of the second right phase shifter satisfy at least one of a first condition and a second condition. In the first condition, the first left phase shift amount is different from the second left phase shift amount. In the second condition, the first right phase shift amount is different from the second right phase shift amount. With this configuration, for example, radio waves can be received with high accuracy and high efficiency. An antenna device for reception with improved characteristics can be provided.

[0155] The first left phase shifter 12a1, the first right phase shifter 12b1, the second left phase shifter 12a2, and the second right phase shifter 12b2 may satisfy either a third condition or a fourth condition. Under the third condition, the relative first phase shift amount of the first left phase shifter 12a1 and the first right phase shifter 12b1 is controlled so that the linearly polarized signal generated (combined) by the signal processing circuit 110 is maximized when the first antenna 11a1 receives a first linearly polarized wave with a first polarization angle. Under the third condition, the relative second phase shift amount of the second left phase shifter 12a2 and the second right phase shifter 12b2 is controlled so that the linearly polarized signal generated (combined) by the signal processing circuit 110 is maximized when the second antenna 11a2 receives a second linearly polarized wave with a second polarization angle. For example, a peak search is performed to estimate the direction of arrival by changing the direction of arrival at which the received power is maximized.

[0156] Under the fourth condition, the first phase shift amount is controlled so that the linearly polarized signal generated (combined) by the signal processing circuit 110 is minimized when the first antenna 11a1 receives the first linearly polarized wave. Under the fourth condition, the second phase shift amount is controlled so that the linearly polarized signal generated (combined) by the signal processing circuit 110 is minimized when the second antenna 11a2 receives the second linearly polarized wave. For example, a null search is performed to estimate the direction of arrival by changing the direction of arrival that minimizes the received power.

[0157] For example, a difference between the first polarization angle and the second polarization angle occurs due to a change in at least one of the first left phase shift amount, the second left phase shift amount, the first right phase shift amount, and the second right phase shift amount. For example, the control circuit 115 is configured to control at least one of the first phase shift amount and the second phase shift amount.

[0158] (Second embodiment) FIG. 10 is a schematic diagram illustrating an antenna device according to the second embodiment. 11A and 11B are graphs illustrating the characteristics of the antenna device. FIG. 12 is a schematic diagram illustrating an antenna device according to the second embodiment. 13A and 13B are graphs illustrating the characteristics of the antenna device according to the second embodiment. 14A and 14B are schematic views illustrating the antenna device according to the second embodiment. . 15A and 15B are schematic views illustrating the antenna device according to the second embodiment.

[0159] For example, in an antenna, the polarization plane of the linearly polarized wave transmitted and received by the antenna is rotated by combining right-handed and left-handed circularly polarized waves. The polarization plane of the linearly polarized wave is rotated by changing the relative phase shift between the right-handed and left-handed circularly polarized waves.

[0160] For example, the polarization angles of the linearly polarized waves transmitted and received by the antennas 11T differ from antenna to antenna, and the relative phase shift between the right-handed circularly polarized waves and the left-handed circularly polarized waves transmitted and received by the antennas 11T differs from antenna to antenna.

[0161] In an array antenna including a plurality of antennas 11T, unwanted radiation occurs when at least one of the amplitude and phase of radio waves transmitted and received by the plurality of antennas 11T changes periodically. The unwanted radiation includes, for example, grating lobes.

[0162] The occurrence of grating lobes can cause problems, such as a reduction in the power of radio waves transmitted and received by an antenna device, or the grating lobes can interfere with other communications.

[0163] As illustrated in FIG. 10 , an antenna device 300 according to this embodiment includes a plurality of antennas 11T. In this example, the number of the plurality of antennas 11T is 64. Circles in FIG. 10 indicate first antennas 11a1. Triangles in FIG. 10 indicate second antennas 11a2. The antenna device 300 includes a plurality of left phase shifters 12L, a plurality of right phase shifters 12R, a signal processing circuit 110, and a control circuit 115, all of which are described in the first embodiment. In the antenna device 300, the plurality of antennas 11T are configured to transmit and receive right-handed circularly polarized waves and left-handed circularly polarized waves. In the antenna device 300, the amplitudes and phases of radio waves transmitted and received by the plurality of antennas 11T may differ from each other.

[0164] In the antenna device 300, eight antennas 11T are arranged in the x-axis direction. Eight antennas 11T are arranged in the y-axis direction. The element spacing d x The element spacing in the y-axis direction is d y is 150 mm. The 64 antennas 11T are arranged at equal intervals in the x-axis direction and the y-axis direction. The element spacing between the multiple antennas 11T does not have to be the same. For example, the multiple antennas 11T may be arranged in a triangular array. In a triangular array, the multiple antennas 11T are arranged in a triangular lattice. The distances between the multiple antennas 11T may differ from one another.

[0165] In FIG. 10, the phase of the radio waves transmitted and received by the first antenna 11a1, indicated by a circle, is 0°. The phase of the radio waves transmitted and received by the second antenna 11a2, indicated by a triangle, is 22.5°. The relative phase difference between the first antenna 11a1 and the second antenna 11a2 is substantially equal to the minimum phase shift amount of the 4-bit phase shifter. In this example, the 32 first antennas 11a1, indicated by a circle, transmit and receive radio waves with a phase shift of 0°. The 32 second antennas 11a2, indicated by a triangle, transmit and receive radio waves with a phase shift of 22.5°.

[0166] In the example shown in FIG. 10, 32 first antennas 11a1 transmit and receive linearly polarized waves with a polarization angle of 0°. 32 second antennas 11a2 transmit and receive linearly polarized waves with a polarization angle of 11.25°. The linearly polarized waves transmitted and received by 64 antennas 11T are combined. The antenna device 300 corresponds to an array antenna that transmits and receives linearly polarized waves with a polarization angle of substantially 5.625°. In the example shown in FIG. 10, the phases of the radio waves transmitted and received by the multiple antennas 11T change periodically on the x-axis.

[0167] 11A and 11B show examples of calculation results of radiation directivity. In the examples of FIGS. 11A and 11B, 64 antennas 11T are calculated as omnidirectional antennas. In the examples of FIGS. 11A and 11B, the power transmitted and received by the 64 antennas is substantially equal to each other. In FIGS. 11A and 11B, the frequency is 1 GHz.

[0168] FIG. 11A shows an example of radiation directivity on a plane parallel to the x-axis. FIG. 11B shows an example of radiation directivity on a plane parallel to the y-axis. In FIGS. 11A and 11B, the solid line corresponds to the radiation directivity of the antenna device 300. In FIGS. 11A and 11B, the dashed line corresponds to the radiation directivity when the phase of radio waves transmitted and received by all 64 antennas 11T is 0°. In FIG. 11B, the dashed line overlaps with the solid line. In FIGS. 11A and 11B, the characteristics of the solid line are normalized by the maximum value of the solid line. The characteristics of the dashed line are normalized by the maximum value of the dashed line. In FIGS. 11A and 11B, the horizontal axis is angle θ. The vertical axis is relative amplitude RA.

[0169] When the phase of the radio waves transmitted and received by all 64 antennas 11T is 0°, the radiation directivity is maximized when the angle θ is 0°. In other words, the angle θ of the beam direction is 0°.

[0170] In Figure 11A (radiation directivity on a plane parallel to the x-axis), the radiation directivity indicated by the solid line is different from the radiation directivity indicated by the dashed line. The radiation directivity value indicated by the solid line is larger than that indicated by the dashed line at angles of ±90°. In Figure 11B (radiation directivity on a plane parallel to the y-axis), the calculation results indicated by the solid line are substantially consistent with the calculation results indicated by the dashed line, regardless of the angle θ.

[0171] From the results in FIG. 11A, it can be seen that in antenna device 300, grating lobes occur in directions where the angle θ is ±90°.

[0172] As shown in Figures 11A and 11B, grating lobes occur when the phases of radio waves transmitted and received by multiple antennas 11T change periodically. For example, the multiple antennas 11T are arranged in a direction substantially parallel to a plane on which radiation directivity is observed. In the multiple antennas 11T, at least one of the amplitude and phase of the radio waves may change periodically. Grating lobes occur when at least one of the amplitude and phase changes periodically in such multiple antennas 11T.

[0173] In the example shown in Fig. 10, the phases of the radio waves transmitted and received by the multiple antennas 11T change periodically in the x-axis direction. The phases of the radio waves transmitted and received by the multiple antennas 11T do not change periodically in the y-axis direction. Grating lobes occur in the radiation directivity of the antenna device 300 in a plane parallel to the x-axis. Grating lobes do not occur in the radiation directivity of the antenna device 300 in a plane parallel to the y-axis.

[0174] For example, in the embodiment, the periodicity of at least one of the amplitude and phase of radio waves transmitted and received by the multiple antennas 11T may be reduced, thereby making it possible to suppress grating lobes in the transmitted and received radio waves, for example.

[0175] 12 illustrates an antenna device 300a according to an embodiment. The antenna device 300a may include, in addition to a plurality of antennas 11T, a plurality of left phase shifters 12L, a plurality of right phase shifters 12R, a signal processing circuit 110, and a control circuit 115 (see FIG. 1). In the antenna device 300a, the arrangement of the first antenna 11a1 indicated by a circle and the second antenna 11a2 indicated by a triangle differs from the arrangement in the antenna device 300. Except for this, the configuration of the antenna device 300a may be similar to the configuration of the antenna device 300, for example.

[0176] As already explained, in the antenna device 300, the phase of the radio waves transmitted and received changes periodically in a plane parallel to the x-axis. In the antenna device 300, grating lobes occur.

[0177] In the antenna device 300a, the first antennas 11a1 indicated by circles and the second antennas 11a2 indicated by triangles are not arranged alternately in the x-axis direction. In the antenna device 300a, there is no periodicity in the phases of the radio waves transmitted and received by the multiple antennas 11T. In the antenna device 300a, grating lobes are reduced compared to the antenna device 300.

[0178] In FIG. 12, the first antenna 11a1, indicated by a circle, is provided in the first partial region 31a. The second antenna 11a2, indicated by a triangle, is provided in the second partial region 31b. In FIG. 12, the first partial region 31a and the second partial region 31b are rectangular. The first partial region 31a and the second partial region 31b are in contact with each other along a plane parallel to the y-axis. In the antenna device 300a, some of the multiple antennas 11T are provided in the first partial region 31a. Another part of the multiple antennas 11T are provided in the second partial region 31b.

[0179] For example, the antenna device 300a may include a base 11BS. The base 11BS may be a substrate or the like. A plurality of antennas 11T are provided on the base 11BS. The base 11BS includes, for example, a contiguous first partial region 31a and a contiguous second partial region 31b. The plurality of antennas 11T may include, for example, a plurality of first antennas 11a1 and a plurality of second antennas 11a2. For example, the plurality of first antennas 11a1 are part of the plurality of antennas 11T. For example, the plurality of second antennas 11a2 are another part of the plurality of antennas 11T. The plurality of first antennas 11a1 are provided in the first partial region 31a. The plurality of first antennas 11a1 are not provided in the second partial region 31b. The plurality of second antennas 11a2 are provided in the second partial region 31b. The plurality of second antennas 11a2 are not provided in the first partial region 31a. Such a configuration can suppress grating lobes, and may be applied when the antenna device according to the embodiment is used for at least one of transmission and reception.

[0180] 13A and 13B show examples of calculation results of the radiation directivity of the antenna device 300a. In FIGS. 13A and 13B, the 64 antennas 11T are omnidirectional antennas. In FIGS. 13A and 13B, the frequency is 1 GHz. In FIGS. 13A and 13B, the powers transmitted and received by the 64 antennas 11T are substantially equal to each other. FIG. 13A shows the radiation directivity in a plane parallel to the x-axis. FIG. 13B shows the radiation directivity in a plane parallel to the y-axis. In FIGS. 13A and 13B, the solid lines correspond to the radiation directivity of the antenna device 300a shown in FIG. 12. In FIGS. 13A and 13B, the solid lines correspond to the radiation directivity when the phase of radio waves transmitted and received by all of the 64 antennas 11T is 0°.

[0181] In Figures 13A and 13B, the solid line characteristics are normalized by the maximum value at the solid line. The dashed line characteristics are normalized by the maximum value at the dashed line. In Figure 13B, the dashed line overlaps with the solid line. In Figures 13A and 13B, the horizontal axis is the angle θ. The vertical axis is the relative intensity RA.

[0182] It can be seen that the grating lobes in the radiation directivity shown in Fig. 13A are suppressed compared to the gratings in the radiation directivity shown in Fig. 11A. The radiation directivities in Fig. 11B and Fig. 13B are generally consistent.

[0183] In the embodiment, when the relative phase shifts of the transmitted and received radio waves differ among the multiple antennas 11T, it is preferable to reduce the periodicity of the arrangement of the antennas whose relative phase shifts of the transmitted and received radio waves differ, thereby suppressing, for example, grating lobes in the radiation directivity.

[0184] For example, an antenna device is divided into a plurality of partial regions. The relative phase shifts of radio waves transmitted and received by antennas 11T included in one of the plurality of partial regions are equal to each other. The relative phase shifts of radio waves transmitted and received by antennas 11T included in another of the plurality of partial regions are equal to each other. The relative phase shifts of radio waves transmitted and received by antenna 11T included in one of the plurality of partial regions differ from those of antenna 11T included in another of the plurality of partial regions. This reduces the periodicity of the arrangement of antennas with different relative phase shifts.

[0185] For example, it is preferable that the number of partial regions provided in the antenna device is small. If the number of partial regions is large, periodicity is likely to occur in the arrangement of the antennas, where the relative phase shifts of the transmitted and received radio waves are different, and for example, grating lobes are likely to increase.

[0186] The shape of each of the plurality of partial regions may be, for example, a rectangle. However, the shape is not limited to this and may be any shape. The shape of each of the plurality of partial regions may be, for example, a circle or a polygon. At least one of the plurality of partial regions may be, for example, a plane. At least one of the plurality of partial regions may be, for example, a three-dimensional shape.

[0187] 14A and 14B show an antenna device 300b according to the embodiment. The antenna device 300b may include, in addition to a plurality of antennas 11T, a plurality of left phase shifters 12L, a plurality of right phase shifters 12R, a signal processing circuit 110, and a control circuit 115 (see FIG. 1). In FIGS. 14A and 14B, circles indicate first antennas 11a1, and triangles indicate second antennas 11a2. In the antenna device 300b, some of the plurality of antennas 11T are provided in the first partial region 31a. Another portion of the plurality of antennas 11T are provided in the second partial region 31b. The first partial region 31a is circular. The second partial region 31b is annular. The second partial region 31b is provided around the first partial region 31a.

[0188] In the antenna device 300b, the area of ​​the first partial region 31a and the area of ​​the second partial region 31b are changed, which makes it possible to change the number of antennas 11T with different relative phase shift amounts, for example.

[0189] The area of ​​the first partial region 31a in Fig. 14A is larger than the area of ​​the first partial region 31a in Fig. 14B. The area of ​​the second partial region 31b in Fig. 14A is smaller than the area of ​​the second partial region 31b in Fig. 14B.

[0190] In the antenna device 300b, N antennas 11T are provided. The polarization angle of the linearly polarized waves transmitted and received by the (Nm) antennas 11T is denoted as τ1. The polarization angle of the linearly polarized waves transmitted and received by the m antennas 11T is denoted as τ2. For example, the polarization angle of the linearly polarized waves transmitted and received by the multiple antennas 11T provided in the first partial region 31a is denoted as τ1. The polarization angle of the linearly polarized waves transmitted and received by the multiple antennas 11T provided in the second partial region 31b is denoted as τ2.

[0191] In this case, the desired polarization angle of the linearly polarized wave transmitted and received by the antenna device 300b is set to τ0. "m" is found by solving equation (10). For example, the area of ​​the first partial region 31a and the area of ​​the second partial region 31b are changed according to the found "m". This makes it possible to control, for example, the polarization angle of the linearly polarized wave transmitted and received by the antenna device 300b. For example, the shape of the first partial region 31a and the shape of the second partial region 31b are changed. This makes it possible to control, for example, the polarization angle of the linearly polarized wave transmitted and received by the antenna device 300b.

[0192] The antenna device 300b may include, for example, a control circuit 115. For example, the control circuit 115 may calculate "m" by solving equation (10). Based on the calculated "m", the control circuit 115 may determine the area of ​​the first partial region 31a and the area of ​​the second partial region 31b. The control circuit 115 may determine the shape of the first partial region 31a and the shape of the second partial region 31b. The phase shift amount of the phase shifter is controlled. The polarization angle of the linearly polarized waves transmitted and received by the multiple antennas 11T is controlled.

[0193] The configuration illustrated in FIG. 14A and the configuration illustrated in FIG. 14B may be reversibly switched. For example, the multiple antennas 11T include multiple first antennas 11a1. The number of the multiple first antennas 11a1 in the first state is different from the number of the multiple first antennas 11a1 in the second state. For example, the multiple antennas 11T include multiple second antennas 11a2. The number of the multiple second antennas 11a2 in the first state is different from the number of the multiple second antennas 11a2 in the second state. The polarization angles of the linearly polarized waves transmitted and received by the multiple antennas 11T are reversibly controlled. The number may be changed by, for example, the control circuit 115. FIG. 14A corresponds to one of the first state and the second state. FIG. 14B corresponds to the other of the first state and the second state. Such a configuration may be applied when the antenna device according to the embodiment is used for at least one of transmission and reception.

[0194] 15A and 15B illustrate an antenna device 300c according to the embodiment. The antenna device 300c may include, in addition to a plurality of antennas 11T, a plurality of left phase shifters 12L, a plurality of right phase shifters 12R, a signal processing circuit 110, and a control circuit 115 (see FIG. 1). In FIGS. 15A and 15B, circles indicate first antennas 11a1, and triangles indicate second antennas 11a2. Some of the plurality of antennas 11T are provided in the first partial region 31a. Another portion of the plurality of antennas 11T are provided in the second partial region 31b. In this example, the first partial region 31a is substantially rectangular, and the second partial region 31b is substantially concave polygonal.

[0195] In the antenna device 300c, the area or shape of the first partial region 31a and the second partial region 31b may be changed, thereby changing the number of antennas that transmit and receive radio waves with different relative phase shift amounts.

[0196] In the antenna device 300a, the antenna device 300b, and the antenna device 300c, two partial regions are provided. In an embodiment, three or more partial regions may be provided. The partial regions may be adjacent to each other. One of the partial regions may be separated from another of the partial regions.

[0197] In the second embodiment, the antenna device may include multiple subarrays. Each of the multiple subarrays includes one or more antennas 11T. For example, the antenna device may include multiple partial regions. Each of the multiple subarrays may correspond to one of the multiple partial regions. Each of the multiple subarrays may be formed on an independent substrate. For example, the relative phase shifts of radio waves transmitted and received by all of the multiple antennas 11T included in the multiple subarrays may be substantially equal to each other. The relative phase shifts of radio waves transmitted and received by an antenna 11T included in one of the multiple subarrays may be different from the relative phase shifts of radio waves transmitted and received by another antenna 11T included in the multiple subarrays. For example, the polarization angle of linearly polarized waves transmitted and received by the antenna 11T can be controlled for each of the multiple subarrays. For example, this simplifies the control of multiple phase shifters. This simplifies the control by the control circuit 115.

[0198] One of the plurality of subarrays may be, for example, a sequential array. In the sequential array, the plurality of antennas 11T are arranged in a continuously rotating manner. Each antenna 11T may be excited with a phase difference between it and the adjacent antenna 11T.

[0199] One of the multiple subarrays may be a linear array, a two-dimensional array, or a three-dimensional array. In a linear array, multiple antennas 11T are arranged in a line. In a two-dimensional array, multiple antennas 11T are arranged on a plane. In a three-dimensional array, multiple antennas 11T are arranged three-dimensionally.

[0200] In the second embodiment, for example, the polarization angles of linearly polarized waves transmitted and received by the multiple antennas 11T differ depending on the antenna 11T. This reduces the periodicity of the arrangement of the antennas 11T that transmit and receive linearly polarized waves with different polarization angles, thereby suppressing grating lobes.

[0201] In the above example, the angle θ of the direction of the transmitting and receiving beam is 0°. In the following example of the embodiment, the angle of the direction of the transmitting and receiving beam does not have to be 0°.

[0202] The configuration illustrated in FIG. 15A and the configuration illustrated in FIG. 15B may be reversibly switched. For example, the number of the first antennas 11a1 in the first state is different from the number of the first antennas 11a1 in the second state. For example, the number of the second antennas 11a2 in the first state is different from the number of the second antennas 11a2 in the second state. FIG. 15A corresponds to one of the first state and the second state. FIG. 15B corresponds to the other of the first state and the second state. Such a configuration may be applied when the antenna device according to the embodiment is used for at least one of transmission and reception.

[0203] 16A and 16B are schematic diagrams illustrating the antenna device according to the second embodiment, and Fig. 17 is a graph illustrating the characteristics of the antenna device according to the second embodiment.

[0204] 16A and 16B includes a plurality of antennas 11T. The antenna device 320 may include a plurality of left phase shifters 12L, a plurality of right phase shifters 12R, a signal processing circuit 110, and a control circuit 115 (see FIG. 1).

[0205] As illustrated in FIGS. 16A and 16B, the antenna device 320 according to the embodiment includes 256 antennas 11T. The 256 antennas 11T include a plurality of first antennas 11a1 and a plurality of second antennas 11a2. In FIG. 16, circles indicate first antennas 11a1, and triangles indicate a plurality of second antennas 11a2. As such, 16 antennas 11T are arranged in the x-axis direction. 16 antennas 11T are arranged in the y-axis direction. The element spacing d in the x-axis direction of the plurality of antennas 11T is x The element spacing d of the multiple antennas 11T in the y-axis direction is 150 mm. y is 150 mm. In this example, the 256 antennas 11T are arranged at the same element intervals in the x-axis direction and the y-axis direction.

[0206] The multiple antennas 11T include an n-th antenna 11an, where "n" is an integer between 1 and 256. The coordinates of the n-th antenna 11an are expressed as (x (n) ,y (n) , z (n) ) The beam direction of the n-th antenna 11an is (θ, φ). The wave number of the n-th antenna 11an is k0. The excitation phase K of the multiple antennas 11T for controlling the beam direction is (n) is given by equation (22).

number

[0207] A linearly polarized wave is generated by combining right-handed circularly polarized waves and left-handed circularly polarized waves transmitted and received by the multiple antennas 11T. A relative phase shift amount ΔΨ is applied to the right-handed circularly polarized waves and left-handed circularly polarized waves transmitted and received by the multiple antennas 11T. (n) From equations (1) and (2), equation (23) is obtained.

number

[0208] From equations (22) and (23), the phase (angle φ R (n) ) and the phase of the left-handed circularly polarized wave (angle φ L (n) ) are given by equations (24) and (25), respectively.

number

number

[0209] The polarization angle τ of the linearly polarized waves transmitted and received by the multiple antennas 11T (n) The polarization angle τ may be different for each of the multiple antennas 11T. (n) When varies periodically, grating lobes occur.

[0210] In the example shown in FIGS. 16A and 16B, the polarization angle τ corresponding to the first antenna 11a1 indicated by a circle (n) is 0°. The polarization angle τ corresponding to the second antenna 11a2 indicated by a triangle (n) In this case, from equation (24), the relative phase difference between the right-handed circularly polarized wave transmitted and received by the first antenna 11a1 and the right-handed circularly polarized wave transmitted and received by the second antenna 11a2 is K (n) , which is substantially equal to the minimum phase shift of 22.5° of a 4-bit phase shifter.

[0211] 16A, first antennas 11a1 and second antennas 11a2 are alternately arranged in a direction parallel to the x-axis. In the example shown in Fig. 16A, grating lobes occur in the radiation directivity in a direction parallel to the x-axis, similar to the example shown in Fig. 10.

[0212] In the example shown in Fig. 16B, the first antennas 11a1 and the second antennas 11a2 are not arranged alternately in the direction parallel to the x-axis, as in the example shown in Fig. 12. In the example shown in Fig. 16B, grating lobes are suppressed in the radiation directivity in the direction parallel to the x-axis, as in the example shown in Fig. 12.

[0213] Fig. 17 shows the calculation results of the radiation directivity of the antenna device 320. In Fig. 17, the multiple antennas 11T are omnidirectional antennas. In Fig. 17, the frequency is 1 GHz. In Fig. 17, the beam direction (θ, φ) is (45°, 0°).

[0214] 17 shows the radiation directivity in a plane parallel to the x-axis. The solid line in FIG. 17 corresponds to the radiation directivity in the configuration shown in FIG. 16A. The chain line in FIG. 17 corresponds to the radiation directivity in the configuration shown in FIG. 16B. The dashed ... (n) 17 corresponds to the radiation directivity when the angle is 0°. In Fig. 17, the characteristics of the solid line are normalized by the maximum value at the solid line. The characteristics of the chain line are normalized by the maximum value at the chain line. The characteristics of the dashed line are normalized by the maximum value at the dashed line.

[0215] As shown in Fig. 17, in the configuration shown in Fig. 16A, grating lobes occur in the -15° direction in the radiation directivity in the direction parallel to the x-axis. On the other hand, in the configuration shown in Fig. 16B, grating lobes in the -15° direction are suppressed in the radiation directivity in the direction parallel to the x-axis.

[0216] In the second embodiment, for example, the polarization angles of the linearly polarized waves transmitted and received by the multiple antennas 11T differ depending on the antenna 11T. In this case, the periodicity of the arrangement of the antennas 11T that transmit and receive linearly polarized waves with different polarization angles may be reduced. This makes it possible to suppress grating lobes even when the beam direction is not 0°.

[0217] FIG. 18 is a schematic diagram illustrating the antenna device according to the second embodiment. 19A and 19B are graphs illustrating the characteristics of the antenna device according to the second embodiment.

[0218] In the embodiment, the polarization angles of the linearly polarized waves transmitted and received by the multiple antennas 11T may differ depending on the antenna 11T. In this case, the multiple antennas 11T transmitting and receiving linearly polarized waves with different polarization angles may be arranged randomly.

[0219] The antenna device 300d illustrated in FIG. 18 may include a plurality of left phase shifters 12L, a plurality of right phase shifters 12R, a signal processing circuit 110, and a control circuit 115 (see FIG. 1), in addition to a plurality of antennas 11T.

[0220] As shown in Fig. 18, an antenna device 300d according to this embodiment includes 64 antennas 11T. The element spacing of the multiple antennas 11T may be the same as the element spacing in the example shown in Fig. 10. For example, the relative phase shift amounts of the multiple antennas 11T may be determined using pseudorandom numbers. For example, the 32 first antennas 11a1 transmit and receive radio waves with a phase shift of 0°. The 32 second antennas 11a2 transmit and receive radio waves with a phase shift of 22.5°.

[0221] When multiple antennas 11T with different relative phase shift amounts are randomly arranged, for example, "m" is calculated by the control circuit 115 (see FIG. 1) based on equation (10). Based on the calculated "m", the relative phase shift amounts of the radio waves transmitted and received by the multiple antennas 11T are determined. For example, the control circuit 115 determines the relative phase shift amounts of the radio waves transmitted and received by the multiple antennas 11T so that the multiple antennas 11T with different relative phase shift amounts are randomly arranged.

[0222] In the random arrangement, a plurality of antennas 11T, each of which transmits and receives radio waves with a different relative phase shift amount, are randomly arranged. In the random arrangement, there is substantially no statistical regularity or statistical bias.

[0223] For example, a "random number" may include a pseudo-random number, which is calculated based on a predetermined algorithm, for example, and may be generated by a linear congruential algorithm and / or a Mersenne Twister algorithm.

[0224] For example, the relative phase shift of the radio waves transmitted and received by the n-th antenna 11an may be determined based on a sequence of N uniform random numbers. The N uniform random number sequences include, for example, values ​​greater than or equal to 0 and less than or equal to 1. For example, when the n-th value of the generated uniform random number sequence is less than or equal to m / N, the polarization angle of the linearly polarized waves of the n-th antenna 11an is set to τ1. When the n-th value of the generated uniform random number sequence is greater than m / N, the polarization angle of the linearly polarized waves of the n-th antenna 11an is set to τ2.

[0225] In the example shown in FIG. 18, in the plurality of antennas 11T (the plurality of first antennas 11a1 and the plurality of second antennas 11a2), τ (n) is determined.

[0226] For example, the relative phase shift amounts of the radio waves transmitted and received by the multiple antennas 11T may be determined using random numbers each time "m" changes. For example, the control circuit 115 (see FIG. 1) may generate a random number sequence. The control circuit 115 may control the phase shift amounts of the multiple left phase shifters 12L and the multiple right phase shifters 12R based on the generated random number sequence.

[0227] For example, a table (information) relating to "m" and the phase shift amount may be created. The table may be stored in, for example, the memory unit 18M (see FIG. 1). The control circuit 115 may acquire information relating to "m" and the phase shift amount from the memory unit 18M. The control circuit 115 may control the phase shift amounts of the multiple left phase shifters 12L and the multiple right phase shifters 12R based on the acquired information. For example, the table may be created and stored in advance. For example, the amount of calculation in the control circuit 115 can be reduced.

[0228] The control circuit 115 controls the amount of phase shift, thereby controlling the polarization angle of the linearly polarized waves transmitted and received by the multiple antennas 11T.

[0229] 19A and 19B show examples of calculation results of radiation directivity characteristics of the antenna device 300d. In FIGS. 19A and 19B, the multiple antennas 11T are omnidirectional antennas. In FIGS. 19A and 19B, the frequency is 1 GHz. In FIGS. 19A and 19B, the power transmitted and received by the multiple antennas 11T is substantially equal. FIG. 19A shows the radiation directivity of the antenna device 300d in a plane parallel to the x-axis. FIG. 19B shows the radiation directivity of the antenna device 300d in a plane parallel to the y-axis. In FIGS. 19A and 19B, the solid line corresponds to the radiation directivity in the configuration shown in FIG. 18. In FIGS. 19A and 19B, the chain line corresponds to the radiation directivity when the phase of radio waves transmitted and received by all antennas 11T is 0°. In FIGS. 19A and 19B, the dashed line corresponds to the radiation directivity of the solid line shown in FIGS. 11A and 11B. That is, the dashed line corresponds to the radiation directivity of the antenna device 300 shown in FIG.

[0230] In Fig. 19B, the radiation directivity indicated by the dashed line substantially matches the radiation directivity indicated by the chain line. In Fig. 19A, the radiation directivity of the antenna device 300d suppresses grating lobes in the ±90° directions compared to the radiation directivity of the antenna device 300 shown in Fig. 10. By randomly arranging multiple antennas 11T that have different relative phase shift amounts of transmitted and received radio waves, grating lobes can be suppressed.

[0231] 19A and 19B show the radiation directivity when the beam direction of the antenna device 300d is 0°. In the embodiment, grating lobes can be suppressed even when the beam direction of the antenna device 300d is not 0°.

[0232] In the embodiment, for example, when the polarization angles of linearly polarized waves transmitted and received by the multiple antennas 11T differ depending on the antenna 11T, the multiple antennas 11T that transmit and receive linearly polarized waves with different polarization angles are randomly arranged. This makes it possible to suppress grating lobes. Such a configuration may be applied when the antenna device according to the embodiment is used for at least one of transmission and reception.

[0233] An antenna device according to the embodiment (e.g., antenna device 100) may further include a control circuit 115 (see FIG. 1). The control circuit 115 may be configured to determine, based on the first polarization angle and the second polarization angle, a polarization angle of a linearly polarized wave generated by another antenna 11T included in the plurality of antennas 11T. The other antenna 11T is, for example, an n-th antenna 11an.

[0234] As shown in FIG. 1 , the multiple left phase shifters 12L further include another left phase shifter 12L. The other left phase shifter 12L is, for example, the n-th left phase shifter 12an. The other left phase shifter 12L is configured to discretely control another left phase of another left-handed circularly polarized signal generated by the other antenna 11T. The multiple right phase shifters 12R further include another right phase shifter 12R. The other right phase shifter 12R is, for example, the n-th right phase shifter 12bn. The other right phase shifter 12R is configured to discretely control another right phase of another right-handed circularly polarized signal generated by the other antenna 11T. For example, the control circuit 115 may be configured to control the other phase shift amount of the other left phase shifter 12L and the phase shift amount of the other right phase shifter 12R based on the polarization angle of the linearly polarized wave generated by the other antenna 11T and the transmission direction of the radio waves transmitted by the multiple antennas 11T. The transmission direction of the radio waves to be transmitted may be the transmission / reception direction. For example, at least one of the number of the plurality of first antennas 11a1 and the number of the plurality of second antennas 11a2 may be changed depending on the transmission / reception direction.

[0235] For example, in the first reference example, the polarization plane of the linearly polarized waves transmitted and received is controlled by combining orthogonal linearly polarized waves. For example, in the second reference example, the polarization plane of the linearly polarized waves transmitted and received by the antenna is controlled by controlling the amplitude difference and phase difference between the orthogonal linearly polarized waves. In the third reference example, the polarization plane of the linearly polarized waves transmitted and received by the antenna is controlled by combining orthogonal circularly polarized waves. For example, a dual circularly polarized antenna that generates linearly polarized waves can be obtained by imparting a phase difference between right-handed circularly polarized waves and left-handed circularly polarized waves. For example, a dual circularly polarized array antenna that generates linearly polarized waves can be obtained by imparting a phase difference between right-handed circularly polarized waves and left-handed circularly polarized waves.

[0236] For example, in a technology for controlling the angle of the polarization plane (polarization angle) of linearly polarized waves transmitted and received by combining orthogonal linearly polarized waves, the amplitude of at least one of the orthogonal linearly polarized waves is reduced when the polarization plane is rotated, which results in power loss due to the polarization angle control.

[0237] On the other hand, in a technology that controls the polarization plane of linearly polarized waves transmitted and received by combining orthogonal circularly polarized waves, the polarization plane can be rotated by controlling the phase difference between the orthogonal circularly polarized waves, without reducing the amplitude of the transmitted and received circularly polarized waves and without power loss due to polarization angle control.

[0238] However, if the phase shifter included in the antenna device is a digital phase shifter with a discrete phase shift, the polarization angle of the linearly polarized wave transmitted and received by the antenna device will be a discrete value corresponding to the minimum phase shift of the digital phase shifter. In this case, it becomes difficult to fine-tune the polarization angle. This results in power loss and a decrease in cross-polarization discrimination. Reducing the minimum phase shift of the digital phase shifter will, for example, increase costs.

[0239] In the embodiment, for example, the polarization plane of linearly polarized waves generated by multiple antennas 11T included in the antenna device is controlled for each antenna 11T. This allows fine adjustment of the polarization angle of the linearly polarized waves transmitted and received by the antenna device. For example, it is not necessary to increase the number of bits of the digital phase shifter used in the antenna device.

[0240] In the embodiment, for example, the multiple antennas 11T generate linearly polarized waves by combining right-handed circularly polarized waves and left-handed circularly polarized waves. The polarization angle of the linearly polarized waves generated for each of the multiple antennas 11T is controlled. This allows the polarization angle of the linearly polarized waves, which are generated by combining the linearly polarized waves transmitted from the multiple antennas 11T, to be finely adjusted in small increments.

[0241] In the embodiment, the polarization angle of the linearly polarized waves of the first antenna 11a1 is τ1, and the polarization angle of the linearly polarized waves of the second antenna 11a2 is τ2. The power of the linearly polarized waves synthesized from the linearly polarized waves transmitted and received by the multiple antennas 11T decreases as the difference between τ1 and τ2 increases, resulting in power loss. A small difference between τ1 and τ2 reduces power loss. For example, the polarization angle of the linearly polarized waves transmitted and received by the multiple antennas 11T is an integer multiple of ½ the first minimum phase shift amount. The polarization angle is substantially minimum when the difference between τ1 and τ2 is ½ the first minimum phase shift amount.

[0242] The embodiment may include a communication device 400 (see FIG. 1 ). The communication device 400 includes an antenna device according to the embodiment (e.g., the antenna device 100) and an electric circuit 410. The electric circuit 410 is configured to be coupled to the antenna device (e.g., the antenna device 100). The electric circuit 410 supplies a signal 410s to the antenna device 100. A radio wave corresponding to the signal 410s is transmitted from the antenna device 100. The electric circuit 410 processes the signal 410s corresponding to the radio wave received by the antenna device 100. The embodiment can provide a wireless device with improved characteristics.

[0243] The embodiments may include the following technical solutions. (Technical proposal 1) a plurality of left phase shifters, the plurality of left phase shifters including a first left phase shifter and a second left phase shifter, the first left phase shifter configured to discretely control a first left phase of a first left-handed circularly polarized signal, and the second left phase shifter configured to discretely control a second left phase of a second left-handed circularly polarized signal; a plurality of right phase shifters, the plurality of right phase shifters including a first right phase shifter and a second right phase shifter, the first right phase shifter configured to discretely control a first right phase of a first right-hand circularly polarized signal, and the second right phase shifter configured to discretely control a second right-hand phase of a second right-hand circularly polarized signal; a plurality of antennas, the plurality of antennas including a first antenna and a second antenna, the first left phase shifter configured to provide the first left-handed circularly polarized signal to the first antenna, the first right phase shifter configured to provide the first right-handed circularly polarized signal to the first antenna, the first antenna configured to transmit a first left-handed circularly polarized wave based on the first left-handed circularly polarized signal and a first right-handed circularly polarized wave based on the first right-handed circularly polarized signal, the second left phase shifter configured to provide the second left-handed circularly polarized signal to the second antenna, the second right phase shifter configured to provide the second right-handed circularly polarized signal to the second antenna, the second antenna configured to transmit a second left-handed circularly polarized wave based on the second left-handed circularly polarized signal and a second right-handed circularly polarized wave based on the second right-handed circularly polarized signal; Equipped with An antenna device, wherein a first polarization angle of a first linear polarization generated by the first left-handed circular polarization and the first right-handed circular polarization is different from a second polarization angle of a second linear polarization generated by the second left-handed circular polarization and the second right-handed circular polarization.

[0244] (Technical proposal 2) a first left phase shift amount of the first left phase shifter is a first integer multiple of a first minimum phase shift amount; a first right phase shift amount of the first right phase shifter is a second integer multiple of a second minimum phase shift amount; the first minimum phase shift amount is the same as the second minimum phase shift amount; The antenna device described in Technical Solution 1, wherein the absolute value of the difference between the first polarization angle and the second polarization angle is greater than or equal to 0.45 times and less than or equal to 0.55 times the first minimum phase shift amount.

[0245] (Technical proposal 3) a first left phase shift amount of the first left phase shifter is a first integer multiple of a first minimum phase shift amount; a first right phase shift amount of the first right phase shifter is a second integer multiple of a second minimum phase shift amount; the first minimum phase shift amount is greater than the second minimum phase shift amount; The antenna device described in Technical Solution 1, wherein the difference between the first polarization angle and the second polarization angle is less than or equal to 0.55 times the first minimum phase shift amount.

[0246] (Technical proposal 4) a base on which the plurality of antennas are provided; the base includes a continuous first subregion and a continuous second subregion; the plurality of antennas includes a plurality of the first antennas and a plurality of the second antennas; the plurality of first antennas are provided in the first partial region and not in the second partial region; The antenna device according to any one of Technical Solutions 1 to 3, wherein the plurality of second antennas are provided in the second partial region and not in the first partial region.

[0247] (Technical proposal 5) the plurality of antennas includes a plurality of the first antennas and a plurality of the second antennas, The antenna device according to any one of Technical Schemes 1 to 3, wherein the plurality of first antennas and the plurality of second antennas are provided randomly.

[0248] (Technical proposal 6) Further comprising a control circuit; the control circuit is configured to determine, based on the first polarization angle and the second polarization angle, a polarization angle of a linearly polarized wave generated by another antenna included in the plurality of antennas; the plurality of left phase shifters further includes the other left phase shifter, the other left phase shifter is configured to discretely control another left phase of another left-handed circularly polarized signal generated by the other antenna; the plurality of right phase shifters further includes the other right phase shifter, the other right phase shifter is configured to discretely control another right phase of another right-handed circularly polarized signal generated by the other antenna; The antenna device described in any one of Technical Solutions 1 to 3, wherein the control circuit is configured to control the other phase shift amount of the other left phase shifter and the other phase shift amount of the other right phase shifter based on the polarization angle of the linearly polarized wave generated by the other antenna and the transmission direction of the radio waves transmitted by the multiple antennas.

[0249] (Technical proposal 7) the plurality of antennas includes a plurality of the first antennas; The antenna device described in Technical Solution 1, wherein the number of the plurality of first antennas in the first state is different from the number of the plurality of first antennas in the second state.

[0250] (Technical proposal 8) a signal processing circuit connectable to the plurality of left phase shifters and the plurality of right phase shifters; The antenna device described in any one of Technical Solutions 1 to 7, wherein the signal processing circuit is configured to control at least one of the amplitude of the first left-handed circularly polarized signal, the amplitude of the second left-handed circularly polarized signal, the amplitude of the first right-handed circularly polarized signal, and the amplitude of the second right-handed circularly polarized signal.

[0251] (Technical proposal 9) the first polarization angle is controlled by controlling at least one of the amplitude of the first left-handed circularly polarized signal and the amplitude of the second left-handed circularly polarized signal; The antenna device described in Technical Solution 8, wherein the second polarization angle is controlled by controlling at least one of the amplitude of the first right-handed circularly polarized signal and the amplitude of the second right-handed circularly polarized signal.

[0252] (Technical proposal 10) An antenna device according to any one of technical proposals 1 to 9; an electrical circuit configured to be coupled to the antenna device; A communication device comprising:

[0253] (Technical proposal 11) a plurality of antennas, the plurality of antennas including a first antenna and a second antenna, the first antenna configured to receive left-handed circularly polarized waves and right-handed circularly polarized waves and output a first left-handed circularly polarized signal and a first right-handed circularly polarized signal, and the second antenna configured to receive the left-handed circularly polarized waves and the right-handed circularly polarized waves and output a second left-handed circularly polarized signal and a second right-handed circularly polarized signal; a plurality of left phase shifters, the plurality of left phase shifters including a first left phase shifter and a second left phase shifter, the first left phase shifter configured to discretely control a first left phase of the first left-handed circularly polarized signal, and the second left phase shifter configured to discretely control a second left phase of the second left-handed circularly polarized signal; a plurality of right phase shifters, the plurality of right phase shifters including a first right phase shifter and a second right phase shifter, the first right phase shifter configured to discretely control a first right phase of the first right-hand circularly polarized signal, and the second right phase shifter configured to discretely control a second right-hand phase of the second right-hand circularly polarized signal; a signal processing circuit configured to be coupled to the plurality of left phase shifters and the plurality of right phase shifters, the signal processing circuit configured to generate a linearly polarized signal indicating linear polarization from the first left-handed circularly polarized signal, the first right-handed circularly polarized signal, the second left-handed circularly polarized signal, and the second right-handed circularly polarized signal; Equipped with a first polarization angle of a first linearly polarized signal generated from the first left-handed circularly polarized signal and the first right-handed circularly polarized signal is different from a second polarization angle of a second linearly polarized signal generated from the second left-handed circularly polarized signal and the second right-handed circularly polarized signal; a first left phase shift amount of the first left phase shifter, a second left phase shift amount of the second left phase shifter, a first right phase shift amount of the first right phase shifter, and a second right phase shift amount of the second right phase shifter satisfy at least one of a first condition and a second condition; In the first condition, the first left phase shift amount is different from the second left phase shift amount, The antenna device, wherein, under the second condition, the first right phase shift amount is different from the second right phase shift amount.

[0254] (Technical proposal 12) The antenna device described in Technical Proposal 11, wherein a difference between the first polarization angle and the second polarization angle occurs by changing at least one of the first left phase shift amount, the second left phase shift amount, the first right phase shift amount, and the second right phase shift amount.

[0255] (Technical proposal 13) the first left phase shifter, the first right phase shifter, the second left phase shifter, and the second right phase shifter satisfy either a third condition or a fourth condition; under the third condition, a first relative phase shift amount in the first left phase shifter and the first right phase shifter is controlled so that the linearly polarized signal is maximized when the first antenna receives a first linearly polarized wave at the first polarization angle, and a second relative phase shift amount in the second left phase shifter and the second right phase shifter is controlled so that the linearly polarized signal is maximized when the second antenna receives a second linearly polarized wave at the second polarization angle, The antenna device described in Technical Proposal 11 or 12, wherein, under the fourth condition, the first phase shift amount is controlled so that the linearly polarized signal is minimized when the first antenna receives the first linearly polarized wave, and the second phase shift amount is controlled so that the linearly polarized signal is minimized when the second antenna receives the second linearly polarized wave.

[0256] (Technical proposal 14) Further comprising a control circuit; The antenna device described in Technical Solution 13, wherein the control circuit is configured to control at least one of the first phase shift amount and the second phase shift amount.

[0257] (Technical proposal 15) the first left phase shift is a first integer multiple of a first minimum phase shift, the first right phase shift is a second integer multiple of the second minimum phase shift, the first minimum phase shift amount is the same as the second minimum phase shift amount; The antenna device according to any one of Technical Schemes 11 to 14, wherein the absolute value of the difference between the first polarization angle and the second polarization angle is 0.45 to 0.55 times the first minimum phase shift amount.

[0258] (Technical proposal 16) the first left phase shift is a first integer multiple of a first minimum phase shift, the first right phase shift is a second integer multiple of the second minimum phase shift, the first minimum phase shift amount is greater than the second minimum phase shift amount; The antenna device according to any one of Technical Schemes 11 to 14, wherein the difference between the first polarization angle and the second polarization angle is equal to or less than 0.55 times the first minimum phase shift amount.

[0259] (Technical proposal 17) a base on which the plurality of antennas are provided; the base includes a continuous first subregion and a continuous second subregion; the plurality of antennas includes a plurality of the first antennas and a plurality of the second antennas; the plurality of first antennas are provided in the first partial region and not in the second partial region; The antenna device according to any one of Technical Solutions 11 to 14, wherein the plurality of second antennas are provided in the second partial region and not in the first partial region.

[0260] (Technical proposal 18) the plurality of antennas includes a plurality of the first antennas and a plurality of the second antennas, The antenna device according to any one of Technical Schemes 11 to 17, wherein the plurality of first antennas and the plurality of second antennas are provided randomly.

[0261] (Technical proposal 19) the plurality of antennas includes a plurality of the first antennas; 19. The antenna device according to any one of Technical Schemes 11 to 18, wherein the number of the plurality of first antennas in the first state is different from the number of the plurality of first antennas in the second state.

[0262] (Technical proposal 20) An antenna device according to any one of technical proposals 11 to 19; an electrical circuit configured to be coupled to the antenna device; A communication device comprising:

[0263] According to the embodiment, it is possible to provide an antenna device and a communication device that can improve characteristics.

[0264] In this specification, "vertical" and "parallel" do not only mean strictly vertical and strictly parallel, but also include variations in the manufacturing process, and may mean substantially vertical and substantially parallel.

[0265] The embodiments of the present invention have been described above with reference to examples. However, the present invention is not limited to these examples. For example, the specific configurations of the elements included in the antenna device, such as the antenna, phase shifter, signal processing circuit, and control circuit, are within the scope of the present invention as long as a person skilled in the art can implement the present invention in a similar manner and obtain similar effects by appropriately selecting them from known ranges.

[0266] Any combination of two or more elements of each example within the scope of technical feasibility is also included within the scope of the present invention as long as it encompasses the gist of the present invention.

[0267] All antenna devices and communication devices that can be implemented by a person skilled in the art by making appropriate design modifications based on the antenna device and communication device described above as embodiments of the present invention also fall within the scope of the present invention, as long as they include the gist of the present invention.

[0268] Within the scope of the concept of the present invention, a person skilled in the art may conceive of various modifications and alterations, and it is understood that these modifications and alterations also fall within the scope of the present invention.

[0269] Although several embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, and are also included in the scope of the invention and its equivalents as defined in the claims. [Explanation of symbols]

[0270] 11B: base, 11T: antenna, 11a1, 11a2, 11aN: first, second and Nth antennas, 12L: left phase shifter, 12R: right phase shifter, 12a1, 12a2, 12aN: first, second and Nth left phase shifters, 12b1, 12b2, 12bN: first, second and Nth right phase shifters, 13L: left transmission line, 13R: right transmission line, 13a1, 13a2, 13aN: first, second and Nth left transmission lines, 13b1, 13a2, 13bN: first, second and Nth right transmission lines, 14L: left line, 14R: right line, 14a1, 14a2, 14aN: first, second and Nth left lines, 14b1, 14b2, 14bN: 1st, 2nd, Nth right lines, 16L: left signal line, 16R: right signal line, 16a1, 16a2, 16aN: 1st, 2nd, Nth left signal lines, 16b1, 16b2, 16bN: 1st, 2nd, Nth right signal lines, 18M: memory unit, 31a: first partial area, 31b: second partial area, 100: antenna device, 110: signal processing circuit, 115: control circuit, 120: feed point, 121: transmission line, 130a: left radiating element, 130b: right radiating element, 131: radiating element, 132: external circuit, 200: beam direction, 201L: left vector, 201R: right vector, 210a, 210b: Vectors, 210a1 to 210a4: Vectors, 210an1, 210bn1: Vectors, 211: Vector, 211a to 211c: Vectors, 300, 300a to 300d, 320: Antenna device, 400: Radio device, 410: Electric circuit, 410s: Signal, 2111: Vector, PA: Polarization angle, Pr: Received power, RA: Relative strength, SL1, SL2: First and second left-handed circularly polarized signals, SR1, SR2: First and second right-handed circularly polarized signals, d x , d y : Element spacing

Claims

1. a plurality of left phase shifters, the plurality of left phase shifters including a first left phase shifter and a second left phase shifter, the first left phase shifter configured to discretely control a first left phase of a first left-handed circularly polarized signal, and the second left phase shifter configured to discretely control a second left phase of a second left-handed circularly polarized signal; a plurality of right phase shifters, the plurality of right phase shifters including a first right phase shifter and a second right phase shifter, the first right phase shifter configured to discretely control a first right phase of a first right-handed circularly polarized signal, and the second right phase shifter configured to discretely control a second right-handed phase of a second right-handed circularly polarized signal; a plurality of antennas, the plurality of antennas including a first antenna and a second antenna, the first left phase shifter configured to provide the first left-handed circularly polarized signal to the first antenna, the first right phase shifter configured to provide the first right-handed circularly polarized signal to the first antenna, the first antenna configured to transmit a first left-handed circularly polarized wave based on the first left-handed circularly polarized signal and a first right-handed circularly polarized wave based on the first right-handed circularly polarized signal, the second left phase shifter configured to provide the second left-handed circularly polarized signal to the second antenna, the second right phase shifter configured to provide the second right-handed circularly polarized signal to the second antenna, the second antenna configured to transmit a second left-handed circularly polarized wave based on the second left-handed circularly polarized signal and a second right-handed circularly polarized wave based on the second right-handed circularly polarized signal; Equipped with An antenna device, wherein a first polarization angle of a first linear polarization generated by the first left-handed circular polarization and the first right-handed circular polarization is different from a second polarization angle of a second linear polarization generated by the second left-handed circular polarization and the second right-handed circular polarization.

2. a first left phase shift amount of the first left phase shifter is a first integer multiple of a first minimum phase shift amount; a first right phase shift amount of the first right phase shifter is a second integer multiple of a second minimum phase shift amount; the first minimum phase shift amount is equal to the second minimum phase shift amount, 2. The antenna device according to claim 1, wherein an absolute value of a difference between the first polarization angle and the second polarization angle is equal to or greater than 0.45 times and equal to or less than 0.55 times the first minimum phase shift amount.

3. a first left phase shift amount of the first left phase shifter is a first integer multiple of a first minimum phase shift amount; a first right phase shift amount of the first right phase shifter is a second integer multiple of a second minimum phase shift amount; the first minimum phase shift amount is greater than the second minimum phase shift amount; 2. The antenna device according to claim 1, wherein a difference between the first polarization angle and the second polarization angle is equal to or less than 0.55 times the first minimum phase shift amount.

4. a base on which the plurality of antennas are provided; the base includes a continuous first subregion and a continuous second subregion; the plurality of antennas includes a plurality of the first antennas and a plurality of the second antennas; the plurality of first antennas are provided in the first partial region and not in the second partial region; The antenna device according to claim 1 , wherein the plurality of second antennas are provided in the second partial region and not in the first partial region.

5. the plurality of antennas includes a plurality of the first antennas and a plurality of the second antennas, The antenna device according to claim 1 , wherein the plurality of first antennas and the plurality of second antennas are provided randomly.

6. Further comprising a control circuit; the control circuit is configured to determine, based on the first polarization angle and the second polarization angle, a polarization angle of a linearly polarized wave generated by another antenna included in the plurality of antennas; the plurality of left phase shifters further includes the other left phase shifter, the other left phase shifter is configured to discretely control another left phase of another left-handed circularly polarized signal generated by the other antenna; the plurality of right phase shifters further includes the other right phase shifter, the other right phase shifter is configured to discretely control another right phase of another right-handed circularly polarized signal generated by the other antenna; The antenna device according to any one of claims 1 to 3, wherein the control circuit is configured to control the phase shift amount of the other left phase shifter and the phase shift amount of the other right phase shifter based on the polarization angle of the linearly polarized wave generated by the other antenna and the transmission direction of the radio waves transmitted by the plurality of antennas.

7. the plurality of antennas includes a plurality of the first antennas; The antenna device according to claim 1 , wherein the number of the plurality of first antennas in the first state is different from the number of the plurality of first antennas in the second state.

8. a signal processing circuit connectable to the plurality of left phase shifters and the plurality of right phase shifters; 2. The antenna device according to claim 1, wherein the signal processing circuit is configured to control at least one of the amplitude of the first left-handed circularly polarized signal, the amplitude of the second left-handed circularly polarized signal, the amplitude of the first right-handed circularly polarized signal, and the amplitude of the second right-handed circularly polarized signal.

9. the first polarization angle is controlled by controlling at least one of the amplitude of the first left-handed circularly polarized signal and the amplitude of the second left-handed circularly polarized signal; 9. The antenna device according to claim 8, wherein the second polarization angle is controlled by controlling at least one of the amplitude of the first right-handed circularly polarized signal and the amplitude of the second right-handed circularly polarized signal.

10. The antenna device according to claim 1; an electrical circuit configured to be coupled to the antenna device; A communication device comprising:

11. a plurality of antennas, the plurality of antennas including a first antenna and a second antenna, the first antenna configured to receive left-handed circularly polarized waves and right-handed circularly polarized waves and output a first left-handed circularly polarized signal and a first right-handed circularly polarized signal, and the second antenna configured to receive the left-handed circularly polarized waves and the right-handed circularly polarized waves and output a second left-handed circularly polarized signal and a second right-handed circularly polarized signal; a plurality of left phase shifters, the plurality of left phase shifters including a first left phase shifter and a second left phase shifter, the first left phase shifter configured to discretely control a first left phase of the first left-handed circularly polarized signal, and the second left phase shifter configured to discretely control a second left phase of the second left-handed circularly polarized signal; a plurality of right phase shifters, the plurality of right phase shifters including a first right phase shifter and a second right phase shifter, the first right phase shifter configured to discretely control a first right phase of the first right-hand circularly polarized signal, and the second right phase shifter configured to discretely control a second right-hand phase of the second right-hand circularly polarized signal; a signal processing circuit configured to be coupled to the plurality of left phase shifters and the plurality of right phase shifters, the signal processing circuit configured to generate a linearly polarized signal indicating linear polarization from the first left-handed circularly polarized signal, the first right-handed circularly polarized signal, the second left-handed circularly polarized signal, and the second right-handed circularly polarized signal; Equipped with a first polarization angle of a first linearly polarized signal generated from the first left-handed circularly polarized signal and the first right-handed circularly polarized signal is different from a second polarization angle of a second linearly polarized signal generated from the second left-handed circularly polarized signal and the second right-handed circularly polarized signal; a first left phase shift amount of the first left phase shifter, a second left phase shift amount of the second left phase shifter, a first right phase shift amount of the first right phase shifter, and a second right phase shift amount of the second right phase shifter satisfy at least one of a first condition and a second condition; In the first condition, the first left phase shift amount is different from the second left phase shift amount, In the second condition, the first right phase shift amount is different from the second right phase shift amount.

12. 12. The antenna device according to claim 11, wherein a difference between the first polarization angle and the second polarization angle occurs by changing at least one of the first left phase shift amount, the second left phase shift amount, the first right phase shift amount, and the second right phase shift amount.

13. the first left phase shifter, the first right phase shifter, the second left phase shifter, and the second right phase shifter satisfy either a third condition or a fourth condition; under the third condition, a first relative phase shift amount in the first left phase shifter and the first right phase shifter is controlled so that the linearly polarized signal is maximized when the first antenna receives a first linearly polarized wave at the first polarization angle, and a second relative phase shift amount in the second left phase shifter and the second right phase shifter is controlled so that the linearly polarized signal is maximized when the second antenna receives a second linearly polarized wave at the second polarization angle, 12. The antenna device according to claim 11, wherein, under the fourth condition, the first phase shift amount is controlled so that the linearly polarized signal is minimized when the first antenna receives the first linearly polarized wave, and the second phase shift amount is controlled so that the linearly polarized signal is minimized when the second antenna receives the second linearly polarized wave.

14. Further comprising a control circuit; The antenna device according to claim 13 , wherein the control circuit is configured to control at least one of the first phase shift amount and the second phase shift amount.

15. the first left phase shift is a first integer multiple of a first minimum phase shift, the first right phase shift is a second integer multiple of a second minimum phase shift, the first minimum phase shift amount is equal to the second minimum phase shift amount, 12. The antenna device according to claim 11, wherein an absolute value of a difference between the first polarization angle and the second polarization angle is 0.45 to 0.55 times the first minimum phase shift amount.

16. the first left phase shift is a first integer multiple of a first minimum phase shift, the first right phase shift is a second integer multiple of a second minimum phase shift, the first minimum phase shift amount is greater than the second minimum phase shift amount; 12. The antenna device according to claim 11, wherein a difference between the first polarization angle and the second polarization angle is equal to or less than 0.55 times the first minimum phase shift amount.

17. a base on which the plurality of antennas are provided; the base includes a continuous first subregion and a continuous second subregion; the plurality of antennas includes a plurality of the first antennas and a plurality of the second antennas; the plurality of first antennas are provided in the first partial region and not in the second partial region; The antenna device according to claim 11 , wherein the plurality of second antennas are provided in the second partial region and not in the first partial region.

18. the plurality of antennas includes a plurality of the first antennas and a plurality of the second antennas, The antenna device according to claim 11 , wherein the plurality of first antennas and the plurality of second antennas are provided randomly.

19. the plurality of antennas includes a plurality of the first antennas; 19. The antenna device according to claim 11, wherein the number of the plurality of first antennas in the first state is different from the number of the plurality of first antennas in the second state.

20. an antenna device according to claim 11; an electrical circuit configured to be coupled to the antenna device; A communication device comprising:

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