Antenna module and antenna driving method

Abstract

The present application provides an antenna module capable of maintaining a good axial ratio and reducing power consumption when a part of a plurality of circularly polarized wave antenna elements (elements) is operated. Each of a plurality of sections has one input / output port and a plurality of antenna ports. Each of a plurality of subarrays includes a plurality of elements connected to any one of the plurality of antenna ports. The plurality of elements forms a sequential array in each subarray. Each of the plurality of sections includes a distribution combiner that distributes a signal input to a first port to the plurality of antenna ports and combines signals input to each of the plurality of antenna ports and outputs from the first port; and a first amplifier connected between the input / output port and the first port. In any one of the plurality of subarrays, the plurality of antenna ports to which the plurality of elements included in one subarray are respectively connected are included in one section.

Description

TECHNICAL FIELD

[0001] The present application relates to an antenna module and an antenna driving method. BACKGROUND

[0002] As an antenna capable of improving an axial ratio of a circularly polarized wave, there is known a sequential array antenna provided with a plurality of circularly polarized wave antenna elements (for example, refer to Patent Literature 1 described below). The sequential array antenna includes a plurality of circularly polarized wave antenna elements arranged in a posture rotated by an arbitrary angle with a main radiation direction as an axis of rotation, and each circularly polarized wave antenna element is excited in a manner having a phase difference corresponding to the rotation angle.

[0003] The sequential array antenna disclosed in Patent Literature 1 described below is composed of a plurality of sequential sub-arrays, and each sequential sub-array includes a plurality of circularly polarized wave antenna elements. The plurality of circularly polarized wave antenna elements included in one sequential sub-array are sequenced, and further the plurality of sequential sub-arrays are sequenced. As one example, if one sequential sub-array is focused on, the reference axes of the four circularly polarized wave antenna elements are each rotated by 45° in order. By adopting such a configuration, even in a case where there is a deviation in the characteristics of each circularly polarized wave antenna element, or in a case where there is an error in the excitation phase or amplitude, a good axial ratio can be obtained.

[0004] Patent Literature 1: Japanese Patent Application Laid-Open No. 3-151703

[0005] Depending on the communication distance, the communication speed (bit rate), there are cases where it is not necessary to cause all of the circularly polarized wave antenna elements to operate. It is desirable that even in a case where a part of the circularly polarized wave antenna elements are caused to operate, a good axial ratio is maintained, and the power consumption is reduced. SUMMARY

[0006] An object of the present application is to provide an antenna module and an antenna driving method capable of maintaining a good axial ratio even in a case where a part of a plurality of circularly polarized wave antenna elements are caused to operate, and capable of reducing the power consumption.

[0007] According to one aspect of the present application, there is provided an antenna module comprising:

[0008] a plurality of sections each having one input / output port and a plurality of antenna ports and amplifying a high frequency signal; and

[0009] a plurality of sub-array antennas each including a plurality of circularly polarized wave antenna elements,

[0010] the plurality of circularly polarized wave antenna elements are each connected to any one of the plurality of antenna ports,

[0011] The plurality of circularly polarized wave antenna elements included in each of the plurality of subarray antennas are arranged in a sequence array for each subarray antenna.

[0012] Each of the plurality of sections includes:

[0013] a combiner that distributes a signal input to the first port to the plurality of antenna ports and combines signals input to each of the plurality of antenna ports and outputs from the first port; and

[0014] a first amplifier connected between the input / output port and the first port,

[0015] In any one of the plurality of subarray antennas, the plurality of circularly polarized wave antenna elements included in one subarray antenna are connected to the plurality of antenna ports included in one section, respectively.

[0016] According to another aspect of the present application, there is provided an antenna driving method,

[0017] is an antenna driving method in which, in an antenna module having a configuration in which a plurality of first amplifiers are used to operate M circularly polarized wave antenna elements, a smaller number m of the circularly polarized wave antenna elements than M are selected and operated, wherein

[0018] Each of the plurality of first amplifiers is configured to operate a plurality of the M circularly polarized wave antenna elements,

[0019] The M circularly polarized wave antenna elements are arranged in a plurality of sequence arrays,

[0020] The m circularly polarized wave antenna elements are selected from the M circularly polarized wave antenna elements and operated so as to satisfy a condition that the selected m circularly polarized wave antenna elements are arranged in one or a plurality of sequence arrays and a condition that the number of the first amplifiers required to operate the m circularly polarized wave antenna elements is the smallest.

[0021] In order to operate all of the circularly polarized wave antenna elements of one subarray antenna, it is sufficient to operate one section. Since the sequence array is configured by all of the circularly polarized wave antenna elements of one subarray antenna, a good axial ratio can be maintained even in the case where one section is operated. In addition, the number of sections required to operate only a part of the plurality of subarray antennas arranged in a sequence array is smaller than the number of subarray antennas operated. Since it is not necessary to operate a section more than the number of subarray antennas operated, power consumption can be reduced. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 is a block diagram of the antenna module of the first embodiment.

[0023] Figure 2 is a block diagram of one section of the antenna module of the first embodiment.

[0024] Figure 3 is a plan view of a plurality of circularly polarized wave antenna elements included in one subarray antenna and constituting a sequential array.

[0025] Figure 4 is a block diagram of the antenna module of the second embodiment.

[0026] Figure 5A is a diagram showing one example of a planar configuration of thirty circularly polarized wave antenna elements of the antenna module of the second embodiment, Figure 5B is a diagram showing the respective rotation angles α of the circularly polarized wave antenna elements in the antenna module of the second embodiment, Figure 5C is a diagram showing the respective rotation angles α of the circularly polarized wave antenna elements in the antenna module of the comparative example.

[0027] Figure 6 is a perspective view showing a coordinate system for a substrate on which a plurality of circularly polarized wave antenna elements are arranged.

[0028] Figure 7A is a graph showing the relationship between the gain and the polar angle θ in the zx cross section (φ = 0°) when all of the circularly polarized wave antenna elements of the antenna module of the second embodiment are caused to operate at the center frequency (58.32 GHz) of channel 1, Figure 7B is a graph showing the axial ratio calculated from the simulation results shown in Figure 7A .

[0029] Figure 8A is a graph showing the relationship between the gain and the azimuthal angle φ in the xy cross section (θ = 90°) when all of the circularly polarized wave antenna elements of the antenna module of the second embodiment are caused to operate at the center frequency (58.32 GHz) of channel 1, Figure 8B is a graph showing the axial ratio calculated from the simulation results shown in Figure 8A .

[0030] Figure 9A and Figure 9B are graphs showing the main polarized wave gain and the cross polarized wave gain, respectively, for each channel.

[0031] Figure 10 are graphs showing the axial ratio calculated from the graphs shown in Figure 9A and Figure 9B for each channel.

[0032] Figure 11 is a plan view showing a planar configuration of circularly polarized wave antenna elements of an antenna module of the second embodiment.

[0033] Figure 12A is a plan view of circularly polarized wave antenna elements and transmission lines used in an antenna module of the third embodiment, Figure 12B is a plan view of circularly polarized wave antenna elements and transmission lines used in an antenna module of a modification of the third embodiment.

[0034] Figure 13A and Figure 13B are plan views of circularly polarized wave antenna elements and transmission lines used in antenna modules of other modifications of the third embodiment, respectively.

[0035] Figure 14A is a view showing a positional relationship of circularly polarized wave antenna elements in a case where three circularly polarized wave antenna elements of a circle are arranged in a row, Figure 14B is a view showing a positional relationship of circularly polarized wave antenna elements in a case where three circularly polarized wave antenna elements of a square are arranged in a row.

[0036] Figure 15A and Figure 15B are plan views of circularly polarized wave antenna elements used in antenna modules of the fourth embodiment, respectively.

[0037] Figure 16 is a perspective view showing an arrangement of a plurality of circularly polarized wave antenna elements of an antenna module of the fifth embodiment.

[0038] Figure 17 is a block diagram of an antenna module of the sixth embodiment.

[0039] BRIEF DESCRIPTION OF THE DRAWINGS: 20…segment, 21…input / output port, 22…antenna port, 23…transmission / reception switching switch, 24…first amplifier, 24L…first low-noise amplifier, 24P…first power amplifier, 26…transmission / reception switching switch, 27…hybrid coupler, 27A…first port, 27B…second port, 28…phase shifter, 29…variable attenuator, 30…transmission / reception switching switch, 31…second amplifier, 31L…second low-noise amplifier, 31P…second power amplifier, 33…transmission / reception switching switch, 35…control circuit, 50…subarray antenna, 51…circularly polarized wave antenna element, 52…power feeding point, 53…reference direction of circularly polarized wave antenna element, 55…substrate, 57…first face, 58…second face, 60…transmission line, 61…hybrid circuit, 61C…geometric center of hybrid circuit, 80…signal port, 81…hybrid coupler. DETAILED DESCRIPTION

[0040] [First Embodiment]

[0041] Referring to the drawings, the antenna module of the first embodiment will be described. Figures 1-3

[0042] Figure 1 is a block diagram of the antenna module of the first embodiment. The antenna module of the first embodiment is provided with a plurality of sections 20 that perform power amplification of high-frequency signals, subarray antennas 50 that are arranged in correspondence with each of the plurality of sections 20, and a plurality of transmission lines 60. Each of the plurality of sections 20 includes one input-output port 21 and a plurality of antenna ports 22. The configuration of the section 20 will be described later with reference to Figure 2

[0043] Each of the plurality of subarray antennas 50 includes a plurality of circularly polarized wave antenna elements 51. The plurality of circularly polarized wave antenna elements 51 included in each of the plurality of subarray antennas 50 are arranged in a sequential array for each subarray antenna 50. The number of the circularly polarized wave antenna elements 51 included in the subarray antenna 50 is equal to the number of the antenna ports 22 of the corresponding section 20. The antenna ports 22 of the section 20 are connected to the circularly polarized wave antenna elements 51 of the corresponding subarray antenna 50 via the transmission line 60.

[0044] The high-frequency signal input from one signal port 80 is distributed to the input-output ports 21 of the plurality of sections 20 via the distribution combiner 81. Each section 20 performs power amplification of the high-frequency signal input to the input-output port 21 and performs phase adjustment and outputs from the plurality of antenna ports 22.

[0045] The reception signal received by the plurality of circularly polarized wave antenna elements 51 is input from the plurality of antenna ports 22 to the section 20, respectively. The section 20 performs amplification and phase adjustment of the reception signal input to each of the plurality of antenna ports 22 and performs synthesis and outputs from the input-output port 21.

[0046] The reception signal output from the input-output port 21 of each of the plurality of sections 20 is synthesized via the distribution combiner 81 and output from the signal port 80.

[0047] Figure 2 is a block diagram of the section 20 Figure 1 The distribution combiner 27 has one first port 27A and a plurality of second ports 27B. The distribution combiner 27 distributes the signal input to the first port 27A to the plurality of second ports 27B and outputs. Also, the signal input to each of the plurality of second ports 27B is synthesized and output from the first port 27A.

[0048] ​​A transmission / reception switching switch 23, a first amplifier 24, and a transmission / reception switching switch 26 are connected between the input / output port 21 and a first port 27A of the distribution combiner 27. The first amplifier 24 includes a first power amplifier 24P and a first low noise amplifier 24L. When the transmission / reception switching switches 23, 26 are in a transmission state, a high frequency signal input from the input / output port 21 is amplified by the first power amplifier 24P and input to the first port 27A of the distribution combiner 27. When the transmission / reception switching switches 23, 26 are in a reception state, a reception signal output from the first port 27A of the distribution combiner 27 is amplified by the first low noise amplifier 24L and output from the input / output port 21.

[0049] A phase shifter 28, a variable attenuator 29, a transmission / reception switching switch 30, a second amplifier 31, and a transmission / reception switching switch 33 are connected between a plurality of second ports 27B of the distribution combiner 27 and each of a plurality of antenna ports 22. The second amplifier 31 includes a second power amplifier 31P and a second low noise amplifier 31L.

[0050] When the transmission / reception switching switches 30, 33 are in a transmission state, a high frequency signal output from the second port 27B of the distribution combiner 27 is output from the antenna port 22 through the phase shifter 28, the variable attenuator 29, and the second power amplifier 31P. When the transmission / reception switching switches 30, 33 are in a reception state, a reception signal input from the antenna port 22 is input to the second port 27B of the distribution combiner 27 through the second low noise amplifier 31L, the variable attenuator 29, and the phase shifter 28.

[0051] The phase shifter 28 adjusts the phase of a signal by control from a control circuit 35. The variable attenuator 29 adjusts the attenuation amount of a signal by control from the control circuit 35. The second power amplifier 31P performs power amplification of a high frequency signal. The second low noise amplifier 31L amplifies a reception signal.

[0052] Figure 3 is a plan view of a plurality of circularly polarized wave antenna elements 51 included in one subarray antenna 50 Figure 1 and constituting a sequential array. The plurality of circularly polarized wave antenna elements 51 have a circular shape in plan view, and are fed from two feed points 52. The two feed points 52 are disposed on two radii that are orthogonal to each other. Circularly polarized waves are radiated by feeding high frequency signals having a phase difference of 90° to the two feed points 52. The direction of rotation (right-handed or left-handed) of the circularly polarized waves radiated is determined by the advance or delay of the phases of the two high frequency signals fed to the two feed points 52. A direction from the geometric center of the circularly polarized wave antenna element 51 toward the midpoint of a line segment having the two feed points 52 as the two ends is referred to as a reference direction 53.

[0053] When the N circularly polarized wave antenna elements 51 constituting a sequence array are sequentially given sequence numbers from 0 to N-1, the reference direction 53 of the i-th circularly polarized wave antenna element 51 has a posture rotated clockwise by a rotation angle a = (i x 360 / N)° with respect to the reference direction 53 of the 0-th circularly polarized wave antenna element 51. For example, in the case where three circularly polarized wave antenna elements 51 constitute a sequence array, the reference directions 53 of the other two circularly polarized wave antenna elements 51 are rotated by 120° and 240°, respectively, with respect to the reference direction 53 of the 0-th circularly polarized wave antenna element 51. In the case where four circularly polarized wave antenna elements 51 constitute a sequence array, the reference directions 53 of the other three circularly polarized wave antenna elements 51 are rotated by 90°, 180°, and 270°, respectively, with respect to the reference direction 53 of the 0-th circularly polarized wave antenna element 51.

[0054] However, as an exception, in the case where two circularly polarized wave antenna elements 51 constitute a sequence array, it is preferable to make the rotation angle a 90°.

[0055] Next, the excellent effects of the first embodiment will be described.

[0056] In the antenna module of the first embodiment, there are cases where it is not necessary to make all the circularly polarized wave antenna elements 51 operate depending on the communication distance, the communication rate. For example, in the case where the communication distance is short, or in the case where the communication rate is slow, there are cases where it is possible to ensure sufficient gain even if only a part of the circularly polarized wave antenna elements 51 is made to operate.

[0057] The plurality of circularly polarized wave antenna elements 51 constituting a sequence array have the highest effect of improving the axial ratio in the case where all the circularly polarized wave antenna elements 51 are made to operate. In the case where only a part of the circularly polarized wave antenna elements 51 is made to operate, there are cases where sufficient effects of improving the axial ratio cannot be obtained. In the first embodiment, even in the case where only one of the plurality of sections 20 is made to operate, all the circularly polarized wave antenna elements 51 constituting one sequence array are made to operate. Therefore, it is possible to obtain sufficient effects of improving the axial ratio.

[0058] In the case where the plurality of circularly polarized wave antenna elements 51 constituting one sequence array are connected across the plurality of sections 20, in order to make all the plurality of circularly polarized wave antenna elements 51 constituting one sequence array operate, it is necessary to make the plurality of sections 20 operate. For example, it is necessary to make the number of second amplifiers 31( Figure 2 ), and the plurality of first amplifiers 24 corresponding to the number of circularly polarized wave antenna elements 51 operate. In contrast to this, in the first embodiment, in order to make all the circularly polarized wave antenna elements 51 constituting one sequence array operate, it is sufficient to make only the number of second amplifiers 31( Figure 2Therefore, low power consumption operation can be performed.

[0059] Next, a modification of the first embodiment will be described.

[0060] The antenna module of the first embodiment has both the transmission function and the reception function, but can also be configured as an antenna module having only the transmission function or only the reception function. In this case, the transmission-reception switching switches 23, 26, 30, 33 are not needed. In addition, the first amplifier 24 can have only one of the first power amplifier 24P and the first low-noise amplifier 24L. Similarly, the second amplifier 31 can have only one of the second power amplifier 31P and the second low-noise amplifier 31L.

[0061] In the first embodiment, the plurality of sections 20 correspond one-to-one to the plurality of subarray antennas 50. As another configuration, the plurality of subarray antennas 50 can correspond to one section 20. That is, the configuration can be such that, in any one of the plurality of subarray antennas 50, the plurality of antenna ports 22 to which the plurality of circularly polarized wave antenna elements 51 included in one subarray antenna 50 are respectively connected are included in one section 20.

[0062] [Second Embodiment]

[0063] Next, the antenna module of the second embodiment will be described with reference to the drawings. Figures 4-10 The same configuration as the antenna module of the first embodiment ( Figure 1 , Figure 2 , Figure 3 ) will be omitted from the description below.

[0064] Figure 4 is a block diagram of the antenna module of the second embodiment. In the first embodiment, the number of antenna ports 22 of one section 20 is equal to the number of circularly polarized wave antenna elements 51 constituting the subarray antenna 50 corresponding to the section 20. In contrast, in the second embodiment, in the combination of the section 20 and the subarray antenna 50, there is a combination in which the number of circularly polarized wave antenna elements 51 is less than the number of antenna ports 22. For example, there is a combination in which the number of antenna ports 22 is four and the number of circularly polarized wave antenna elements 51 of the subarray antenna 50 corresponding thereto is three.

[0065] Figure 5AThis is a schematic diagram showing an example of a planar arrangement of thirty circularly polarized antenna elements 51. The thirty circularly polarized antenna elements 51 are arranged on a substrate 55 in a matrix of six rows and five columns. Power is supplied to the thirty circularly polarized antenna elements 51 from eight segments 20. Each of the eight segments 20 has four antenna ports 22. This results in a total of thirty-two antenna ports 22. Serial numbers are assigned to the eight segments 20, and to the thirty-two antenna ports. Serial numbers assigned to segments 20 are indicated by numbers prefixed with "S," while serial numbers assigned to antenna ports 22 are indicated by numbers prefixed with "#." The eight segments 20 are serially numbered from S0 to S7, and the thirty-two antenna ports 22 are serially numbered from #0 to #31. The four antenna ports 22 assigned to the jth segment 20 are serially numbered 4j, 4j+1, 4j+2, and 4j+3, respectively.

[0066] Circularly polarized antenna elements 51 connected to the same segment 20 are surrounded by a dotted line, the area within the dotted line is hatched, and the serial number of the corresponding segment 20 is indicated by a numeral followed by an "S." Furthermore, the serial number of the antenna port 22 to which each circularly polarized antenna element 51 is connected is indicated by a numeral followed by a "#."

[0067] Three circularly polarized antenna elements 51 are connected to each of the segments 20 with serial numbers S1 and S2. That is, one of the four antenna ports 22 in each of the segments 20 with serial numbers S1 and S2 is not connected to a circularly polarized antenna element 51. More specifically, no circularly polarized antenna element 51 is connected to the antenna ports 22 with serial numbers #7 and #8. For each of the other segments 20, four antenna ports 22 are connected to circularly polarized antenna elements 51.

[0068] Figure 5B is a graph showing the rotation angle α ( Figure 3 ). In the second embodiment, the multiple circularly polarized antenna elements 51 of the subarray antenna 50 connected to a segment 20 form a sequential array. Therefore, the four circularly polarized antenna elements 51 connected to the segments 20 with serial numbers S0, S3, S4, S5, S6, and S7 have rotation angles α of 0°, 90°, 180°, and 270°, respectively. The three circularly polarized antenna elements 51 connected to the segments 20 with serial numbers S1 and S2 have rotation angles α of 0°, 120°, and 240°, respectively.

[0069] Figure 5C is a graph showing the rotation angle α ( Figure 3). The rotation angle α of each circularly polarized antenna element 51 is set so that thirty circularly polarized antenna elements 51 form a sequential array. Specifically, the rotation angle α of the eight circularly polarized antenna elements 51 arranged in the lower left area is set to 0°, the rotation angle α of the seven circularly polarized antenna elements 51 arranged in the upper left area is set to 90°, the rotation angle α of the seven circularly polarized antenna elements 51 arranged in the lower right area is set to 180°, and the rotation angle α of the eight circularly polarized antenna elements 51 arranged in the upper right area is set to 270°.

[0070] In the comparative example, the thirty circularly polarized antenna elements 51 collectively form a sequential array, but the three or four circularly polarized antenna elements 51 connected to each segment 20 do not form a sequential array. For example, the four circularly polarized antenna elements 51 connected to the segment 20 with the serial number S0 all have a rotation angle α of 0°, while the three circularly polarized antenna elements 51 connected to the segment 20 with the serial number S1 each have a rotation angle α of 0°, 180°, and 180°.

[0071] Next, the excellent effects of the second embodiment will be described.

[0072] In order to confirm the excellent effect of the second embodiment, the antenna module ( Figure 5B ) and the antenna module of the comparative example ( Figure 5C ) was used to simulate the gain and axis ratio. Figures 6-10 The simulation results are described in detail with reference to FIG.

[0073] Figure 6 This is a perspective diagram showing the coordinate system for a substrate 55 on which thirty circularly polarized antenna elements 51 are arranged. The center of the thirty circularly polarized antenna elements 51 arranged in six rows and five columns is used as the origin, and the normal direction of the substrate 55 (the front direction of the plurality of circularly polarized antenna elements 51) is set as the positive x-axis direction. The row direction of the thirty circularly polarized antenna elements 51 arranged in six rows and five columns is set as the y-axis direction, and the column direction is set as the z-axis direction.

[0074] The polar angle relative to the positive z-axis is expressed as θ, and the azimuth angle relative to the positive x-axis is expressed as φ. The radiation patterns in the zx and xy planes were determined through simulation. The excitation frequencies of the multiple circularly polarized antenna elements 51 are the center frequencies of channels 1 through 4 of the IEEE 802.11ay wireless communication standard. The center frequencies of channels 1 through 4 are 58.32 GHz, 60.48 GHz, 62.64 GHz, and 64.8 GHz, respectively.

[0075] The thirty circularly polarized antenna elements 51 are designed to radiate right-handed circularly polarized waves, but generally contain some left-handed circularly polarized components. In other words, the axial ratio of the circularly polarized waves radiated from each circularly polarized antenna element 51 is greater than 0 dB. Furthermore, the excitation phases of the multiple circularly polarized antenna elements 51 are adjusted so that the right-handed circularly polarized waves form the main beam in the positive direction of the x-axis (θ = 90°, φ = 0°).

[0076] For all segments 20 ( Figure 5A ), operating the four segments 20 with serial numbers S0 to S3, and operating the two segments 20 with serial numbers S0 and S1. If all segments 20 are operated, all thirty circularly polarized antenna elements 51 are operated. If the four segments 20 with serial numbers S0 to S3 are operated, the fourteen circularly polarized antenna elements 51 with serial numbers #0 to #15 are operated. If the two segments 20 with serial numbers S0 and S1 are operated, the seven circularly polarized antenna elements 51 with serial numbers #0 to #6 are operated.

[0077] Figure 7A The antenna module of the second embodiment ( Figure 5B ) is a graph showing the relationship between gain and polar angle θ in the zx cross section (φ = 0°) when all circularly polarized antenna elements 51 are operating at the center frequency (58.32 GHz) of channel 1. The horizontal axis represents polar angle θ in degrees, and the vertical axis represents gain in dBi. The hollow circular symbols in the graph represent the gain of the main polarization wave (right-handed circular polarization wave), and the fully blacked-out circular symbols represent the gain of the cross-polarization wave (left-handed circular polarization wave). A main beam of the main polarization wave is formed in the direction of polar angle θ = 90° (the front direction).

[0078] Figure 7B It means according to Figure 7A The graph of the axial ratio obtained from the simulation results is shown. It can be seen that the axial ratio is the smallest in the front direction.

[0079] Figure 8A The antenna module of the second embodiment ( Figure 5B ) is a graph showing the relationship between gain and azimuth angle φ in an xy cross-section (θ = 90°) when all circularly polarized antenna elements 51 are operating at the center frequency (58.32 GHz) of channel 1. The horizontal axis represents azimuth angle φ in units of "°," and the vertical axis represents gain in units of "dBi." The hollow circular symbols in the graph represent the gain of the main polarization (right-handed circularly polarized wave), and the fully blacked-out circular symbols represent the gain of the cross-polarization (left-handed circularly polarized wave). A main beam of the main polarization is formed in the direction of azimuth angle φ = 0° (the forward direction).

[0080] Figure 8BIt means according to Figure 8A The graph of the axial ratio obtained from the simulation results is shown. It can be seen that the axial ratio is the smallest in the front direction.

[0081] For the antenna module of the second embodiment ( Figure 5B ) and the antenna module of the comparative example ( Figure 5C ), the same simulation is also performed on multiple conditions with different numbers of segments 20 and channels to obtain the gains and axial ratios of the main polarization wave and the cross polarization wave.

[0082] Figure 9A as well as Figure 9B The following are graphs showing the main polarization gain and cross polarization gain for each channel. Figure 9A as well as Figure 9B In the figure, the solid line with a circle symbol represents the antenna module of the second embodiment ( Figure 5B ), the dotted line with a triangle symbol represents the antenna module of the comparative example ( Figure 5C ). The thickness of the solid and dashed lines corresponds to the number of segments 20 in operation. The thickest solid and dashed lines represent the simulation results when all segments 20 are in operation. The second thickest solid and dashed lines represent the simulation results when four segments 20 with sequence numbers S0 to S3 are in operation. The thinnest solid and dashed lines represent the simulation results when two segments 20 with sequence numbers S0 and S1 are in operation.

[0083] If the number of operating segments 20 (that is, the number of operating circularly polarized wave antenna elements 51) decreases, the main polarization gain decreases. However, the main polarization gain ( Figure 9A )In the antenna module of the second embodiment ( Figure 5B ) and the antenna module of the comparative example ( Figure 5C ) and the differences between channels are also small.

[0084] However, the cross-polarization gain ( Figure 9B )In the antenna module of the second embodiment ( Figure 5B ) and the antenna module of the comparative example ( Figure 5C ) produces a large difference. In particular, in the case of the comparative example, the cross-polarization wave gain of channel 4 is larger than that of other channels.

[0085] Figure 10 Each channel is displayed according to Figure 9A as well as Figure 9B The graph shown is a graph of the axis ratio calculated by . The solid line, dotted line, circle symbol and triangle symbol in the graph correspond to the simulation conditions and Figure 9A as well as Figure 9B The same is true for the diagram shown.Figure 5C ) of channel 4 is significantly larger than the axial ratios of the other channels when the number of segments 20 in operation is four or two, and the axial ratio exceeds 3dB. Figure 5B )'s axial ratio, even when the number of segments 20 performing the operation is small, it is possible to ensure a good axial ratio, for example, an axial ratio of less than 3dB, in all channels.

[0086] Next, get Figure 10 The reasons for the simulation results shown are explained.

[0087] If the segments 20 ( Figure 5A ) action, the seven circularly polarized wave antenna elements 51 ( Figure 5A ) to perform the action. At this time, in the comparative example ( Figure 5C ), the rotation angle α of the five circularly polarized wave antenna elements 51 is 0°, and the rotation angle α of the two circularly polarized wave antenna elements 51 is 180°.

[0088] If the four segments 20 ( Figure 5A ) action, the fourteen circularly polarized wave antenna elements 51 ( Figure 5A ) to perform the action. At this time, in the comparative example ( Figure 5C ), the rotation angle α of seven circularly polarized wave antenna elements 51 is 0°, and the rotation angle α of the remaining seven circularly polarized wave antenna elements 51 is 180°.

[0089] As described above, in the comparative example, when only a part of the segments 20 are operated, the plurality of operated circularly polarized antenna elements 51 do not form a sequential array. Therefore, the excellent effect of the sequential array, such as improving the axial ratio, cannot be obtained.

[0090] In contrast, in the antenna module of the second embodiment, when the two segments 20 with serial numbers S0 and S1 are in operation, and when the four segments 20 with serial numbers S0 to S3 are in operation, the multiple circularly polarized antenna elements 51 in operation form a sequential array consisting of three or four circularly polarized antenna elements 51. Therefore, even when only a portion of the segments 20 are in operation, the axial ratio improvement effect of the sequential array can be achieved.

[0091] In addition, if Figure 9A As shown, the main polarization gain depends on the number of operating segments 20. By reducing the number of operating segments 20 to obtain the required gain, power-saving operation can be achieved. In the second embodiment, a sufficient axial ratio can be ensured even when performing power-saving operation.

[0092] Next, referring to Figure 11 , a preferred configuration of the plurality of circularly polarized wave antenna elements 51 will be described.

[0093] Figure 11 is a view showing a planar configuration of the circularly polarized wave antenna elements 51 of the antenna module of the second embodiment. In Figure 11 , as in Figure 5A , the plurality of circularly polarized wave antenna elements 51 included in one subarray antenna 50 are shown surrounded by a broken line. Next, a preferred upper limit value of the interval of the circularly polarized wave antenna elements 51 will be described.

[0094] The geometric centers of all the circularly polarized wave antenna elements 51 included in one subarray antenna 50 are connected by line segments in a number one less than the number of the circularly polarized wave antenna elements, and the total length of the plurality of line segments is made the shortest. At this time, the center-to-center distance (interval) of the two circularly polarized wave antenna elements 51 connected by the longest line segment is expressed as Gl.

[0095] For example, the interval Gl is given by the interval of two circularly polarized wave antenna elements 51 adjacent in the row direction or the column direction for the four circularly polarized wave antenna elements 51 connected by the section 20 of serial number SO. The interval Gl is given by the interval in the oblique direction between the circularly polarized wave antenna element 51 of serial number #26 and the circularly polarized wave antenna element 51 of serial number #27 for the four circularly polarized wave antenna elements 51 connected by the section 20 of serial number S6.

[0096] In the case where one subarray antenna 50 is made to operate, in order to suppress the generation of a grating lobe, it is preferable that the interval Gl be made to be below the free space wavelength corresponding to the resonance frequency of the circularly polarized wave antenna element 51 in any one subarray antenna 50.

[0097] In addition, not limited to one subarray antenna 50, the geometric centers of all the circularly polarized wave antenna elements 51 are connected by line segments in a number one less than the number of the circularly polarized wave antenna elements, and the total length of the plurality of line segments is made the shortest. At this time, the center-to-center distance (interval) of the two circularly polarized wave antenna elements 51 connected by the longest line segment is expressed as G2. In the second embodiment, the interval G2 is given by the interval of two circularly polarized wave antenna elements 51 adjacent in the row direction or the column direction.

[0098] In the case where all the subarray antennas 50 are made to operate, in order to suppress the generation of a grating lobe, it is preferable that the interval G2 be made to be below the free space wavelength corresponding to the resonance frequency of the circularly polarized wave antenna element 51.

[0099] In referring to Figures 5A-10In the simulation illustrated in the accompanying drawings, the number of segments 20 is set to eight, and the number of circularly polarized antenna elements 51 is set to thirty, but other numbers may be used. Furthermore, while the number of circularly polarized antenna elements 51 included in one subarray antenna 50 is set to three or four, other numbers may also be used.

[0100] [Third embodiment]

[0101] Next, refer to Figure 12A The antenna module of the third embodiment is described. Figure 1 、 Figure 2 、 Figure 3 ) are omitted. In the first embodiment, the circularly polarized wave antenna element 51 and the transmission line 60 ( Figure 1 ) are described in detail, but in the third embodiment, the detailed connection structure between the circularly polarized wave antenna element 51 and the transmission line 60 is clarified.

[0102] Figure 12A This is a top view of a circularly polarized antenna element 51 and a transmission line 60 used in the antenna module of the third embodiment. The circularly polarized antenna element 51 has a rectangular shape when viewed from above, for example, a square. A feed point 52 is provided on a line segment extending from the center of the square to the midpoints of two adjacent sides of the square.

[0103] Transmission line 60 is connected to two power supply points 52 via hybrid circuit 61. Hybrid circuit 61 consists of four transmission lines arranged along the four sides of a rectangle. The positions corresponding to the four vertices of the rectangle function as the four ports P1, P2, P3, and P4 of hybrid circuit 61. Transmission line 60 is connected to port P1 of hybrid circuit 61, and the two power supply points 52 are connected to ports P3 and P4 of hybrid circuit 61, respectively. An open stub is connected to port P2. Alternatively, a short stub, a non-reflective terminal, or a transmission line of a certain length can be connected to port P2 instead of an open stub.

[0104] The high-frequency signal transmitted through the transmission line 60 and input to port P1 is output from ports P3 and P4 with a phase difference of 90°. This excites the circularly polarized antenna element 51 to radiate circularly polarized waves, for example, right-handed circularly polarized waves. When the circularly polarized antenna element 51 receives right-handed circularly polarized waves, it synthesizes the received signal and outputs it from port P1 to the transmission line 60. When the transmission line 60 is connected to port P2 of the hybrid circuit 61, the circularly polarized antenna element 51 radiates left-handed circularly polarized waves and can also receive left-handed circularly polarized waves.

[0105] Figure 12BFig. 9 is a plan view of a circularly polarized wave antenna element 51 and a transmission line 60 used by an antenna module of a modification of the third embodiment. The shape of the circularly polarized wave antenna element 51 used by the antenna module of this modification in plan view is circular. Power feeding points 52 are provided on two radii of the circle that are orthogonal to each other. As with this modification, the shape of the circularly polarized wave antenna element 51 can be made circular.

[0106] Next, referring to Figure 13A and Figure 13B , an antenna module of another modification of the third embodiment will be described.

[0107] Figure 13A and Figure 13B are a plan view of a circularly polarized wave antenna element 51 and a transmission line 60 used by an antenna module of this modification, respectively. In Figure 13A the modification shown in Fig. 9, the circularly polarized wave antenna element 51 is square, and in Figure 13B the modification shown in Fig. 10, the circularly polarized wave antenna element 51 is circular. In Figure 12A the third embodiment shown in Fig. 1 and Figure 12B the modification of the third embodiment shown in Fig. 2, the geometric center of the hybrid circuit 61 is disposed outside the circularly polarized wave antenna element 51 in plan view. In contrast, in Figure 13A the modification shown in Fig. 9, the geometric center 61C of the hybrid circuit 61 is disposed inside the circularly polarized wave antenna element 51 in plan view. By being so disposed, space saving can be achieved.

[0108] The electrical length of one side of the square circularly polarized wave antenna element 51 and the electrical length of the diameter of the circular circularly polarized wave antenna element 51 are approximately equal to 1 / 2 of the wavelength corresponding to the resonant frequency of the circularly polarized wave antenna element 51. In contrast, the electrical length of each of the four transmission lines that make up the hybrid circuit 61 is approximately equal to 1 / 4 of the wavelength corresponding to the resonant frequency of the circularly polarized wave antenna element 51. Therefore, the hybrid circuit 61 can be disposed so as to be contained in the circularly polarized wave antenna element 51 in plan view. By disposing the hybrid circuit 61 so as to be contained in the circularly polarized wave antenna element 51, space saving can be further promoted.

[0109] In addition, in the case where a series array is constituted by a plurality of circularly polarized wave antenna elements 51, the circularly polarized wave antenna elements 51 are disposed in a posture in which each is rotated by a certain constant angle, as shown in Figure 3 . As shown in Figure 12A , in the configuration in which the hybrid circuit 61 is disposed outside the circularly polarized wave antenna element 51 in plan view, there is a case where the hybrid circuits 61 connected to two adjacent circularly polarized wave antenna elements 51, respectively, interfere with each other in space. In contrast, in Figure 13A and Figure 13BIn the modification shown, at least a portion of the hybrid circuit 61 overlaps the circularly polarized wave antenna element 51 in plan view, so that an excellent effect of not easily causing spatial interference between the hybrid circuits 61 can be obtained.

[0110] Next, the preferred shape of the circularly polarized wave antenna element 51 will be described with reference to Figure 14A and Figure 14B .

[0111] Figure 14A is a view showing the positional relationship of the circularly polarized wave antenna elements 51 in the case where three circularly polarized wave antenna elements 51 of a circular shape are arranged in a row. Figure 14B is a view showing the positional relationship of the circularly polarized wave antenna elements 51 in the case where three circularly polarized wave antenna elements 51 of a square shape are arranged in a row.

[0112] In either of the cases of Figure 14A and Figure 14B , the reference directions 53 of the second and third circularly polarized wave antenna elements 51 from the left are respectively rotated 45° and 90° clockwise with respect to the reference direction 53 of the leftmost circularly polarized wave antenna element 51.

[0113] In the case where the shape of the circularly polarized wave antenna element 51 is circular ( Figure 14A ), the posture of the outer shape of the circularly polarized wave antenna element 51 does not change even if the direction of the reference direction 53 is changed. In contrast, in the case where the shape of the circularly polarized wave antenna element 51 is square ( Figure 14B ), the posture of the outer shape of the circularly polarized wave antenna element 51 changes if the reference direction 53 is rotated by 45°. For example, in the example shown in Figure 14B , one diagonal line of the central circularly polarized wave antenna element 51 is parallel to the arrangement direction of the three circularly polarized wave antenna elements 51.

[0114] In the case where the resonant frequency of the circular circularly polarized wave antenna element 51 is the same as that of the square circularly polarized wave antenna element 51, the length of one side of the square circularly polarized wave antenna element 51 is approximately equal to the diameter of the circular circularly polarized wave antenna element 51. The diagonal line of the square is longer than one side, so if the arrangement interval of the plurality of circularly polarized wave antenna elements 51 is made narrow, a portion of one circularly polarized wave antenna element 51 comes into contact with the adjacent circularly polarized wave antenna element 51.

[0115] In contrast, in the case where the circularly polarized wave antenna element 51 is circular, even if the reference directions 53 of two circularly polarized wave antenna elements 51 adjacent to each other are shifted by 45°, the two do not come into contact. In the case where a plurality of circularly polarized wave antenna elements 51 are arranged at a narrow interval, it is preferable that the circularly polarized wave antenna element 51 be circular.

[0116] [Fourth Embodiment]

[0117] Next, the antenna module of the fourth embodiment will be described with reference to Figure 15A and Figure 15B The antenna module of the fourth embodiment will be described. Hereinafter, the same configuration as the antenna module of the first embodiment (Figs. 1 to 3) will be omitted from the description. Figure 1 , Figure 2 , Figure 3 ) will be omitted from the description.

[0118] Figure 15A and Figure 15B are plan views of the circularly polarized wave antenna elements 51 used in the antenna module of the fourth embodiment. In the first embodiment, the circularly polarized wave is generated by supplying the high-frequency signals having a phase difference from two feeding points 52 (Figs. 1 and 2) to each circularly polarized wave antenna element 51. In contrast, in the fourth embodiment, a perturbation element is used as the circularly polarized wave antenna element 51. Figure 3

[0119] Figure 15A The circularly polarized wave antenna element 51 shown in Fig. 7 has a shape in which two apexes on one diagonal line of a square element are cut off in a triangular shape. The feeding point 52 is provided on a line segment connecting the midpoint of one side to the center of the circularly polarized wave antenna element 51.

[0120] Figure 15B The circularly polarized wave antenna element 51 shown in Fig. 8 has a shape in which a notch is provided at positions corresponding to both ends of a diameter of a circular element. The feeding point 52 is disposed on a radius at an angle of 45° from the diameter having the notch positions as both ends.

[0121] Next, the excellent effects of the fourth embodiment will be described.

[0122] In the fourth embodiment, the feeding point 52 provided to each circularly polarized wave antenna element 51 is one, so that the feeding can be performed without passing through the hybrid circuit 61 shown in Figs. 1 and 2. Figure 12A Thus, the degree of freedom of the layout of the transmission line 60 can be improved.

[0123] [Fourth Embodiment]

[0124] Next, the antenna module of the fourth embodiment will be described with reference to Figure 16 The antenna module of the fourth embodiment will be described. Hereinafter, the same configuration as the antenna module of the first embodiment (Figs. 1 to 3) will be omitted from the description. Figure 4

[0125] Figure 16 ​​is a perspective view showing the arrangement of the plurality of circularly polarized wave antenna elements 51 of the antenna module of the fifth embodiment. The first face 57 and the second face 58 cross each other perpendicularly. A part of the plurality of subarray antennas 50 are arranged along the first face 57, and the remaining subarray antennas 50 are arranged along the second face 58. That is, the front direction of the part of the subarray antennas 50 and the front direction of the remaining subarray antennas 50 are different from each other.

[0126] Next, the excellent effects of the fifth embodiment are described.

[0127] With the antenna module of the fifth embodiment, a wider coverage range can be obtained. In addition, in a case where the main beam is desired to be directed toward the front direction of the first face 57, the subarray antennas 50 arranged along the first face 57 are caused to operate, and the subarray antennas 50 arranged along the second face 58 are caused not to operate, whereby power saving can be achieved. Similarly, in a case where the main beam is desired to be directed toward the front direction of the second face 58, power saving can also be achieved. Furthermore, in a case where the main beam is directed toward either one of the front direction of the first face 57 and the front direction of the second face 58, a good axial ratio can be obtained.

[0128] Next, a modification of the fifth embodiment is described.

[0129] In the fifth embodiment, the plurality of subarray antennas 50 are arranged along two planes of the first face 57 and the second face 58, respectively. The plurality of subarray antennas 50 can also be arranged along more than three planes whose front directions are different from each other. With this configuration, the coverage range can be further expanded. In addition, the direction toward which the main beam is directed can be controlled more finely.

[0130] [Sixth Embodiment]

[0131] Next, the sixth embodiment is described with reference to Figure 17 The antenna module of the sixth embodiment is described. Hereinafter, the same configuration as the antenna module of the second embodiment (Figs. 1 and 5) is omitted from description. Figure 4

[0132] Figure 17 is a block diagram of the antenna module of the sixth embodiment. In the sixth embodiment, the second amplifier 31 provided in the antenna module of the second embodiment is omitted. Figure 4 Figure 2 The combining synthesizer 27 distributes the signal input to the first port 27A to the plurality of antenna ports 22 via the second port 27B and the phase shifter 28. Also, the signals respectively input to the plurality of antenna ports 22 and transferred to the second port 7B via the phase shifter 28 are combined and output from the first port 27A.

[0133] Next, the excellent effects of the sixth embodiment are described.​​

[0134] In the sixth embodiment, as in the second embodiment, sufficient axial ratio can be ensured even when only a part of the sections 20 is made to operate. Thus, both power saving operation and axial ratio improvement can be achieved.

[0135] [Seventh Embodiment]

[0136] Next, the antenna driving method of the seventh embodiment will be described.

[0137] In the second embodiment shown in FIGS. 8A and 8B, thirty circularly polarized wave antenna elements 51 are made to operate by eight first amplifiers 24. Also, any one of the eight first amplifiers 24 is made to operate three or four of the thirty circularly polarized wave antenna elements 51. Figure 5A and Figure 5B In the second embodiment shown in FIGS. 8A and 8B, thirty circularly polarized wave antenna elements 51 are made to operate by eight first amplifiers 24. Also, any one of the eight first amplifiers 24 is made to operate three or four of the thirty circularly polarized wave antenna elements 51.

[0138] In the seventh embodiment, the number of the first amplifiers 24 is not limited to eight, and the number of the circularly polarized wave antenna elements 51 is not limited to thirty. Also, the number of the circularly polarized wave antenna elements 51 constituting one sequence array is not limited to three or four. For example, a configuration is adopted in which M circularly polarized wave antenna elements are made to operate by a plurality of first amplifiers 24, and any one of the plurality of first amplifiers 24 is made to operate a plurality of the M circularly polarized wave antenna elements 51. Here, M is an integer of four or more. The M circularly polarized wave antenna elements 51 constitute a plurality of sequence arrays.

[0139] When m circularly polarized wave antenna elements 51 less than M are selected and made to operate, the m circularly polarized wave antenna elements 51 are selected from the M circularly polarized wave antenna elements 51 so as to satisfy the following two conditions. The first condition is that the selected m circularly polarized wave antenna elements constitute one or a plurality of sequence arrays. The second condition is that the number of the first amplifiers 24 required to make the m circularly polarized wave antenna elements operate is the least.

[0140] Next, the excellent effects of the seventh embodiment will be described.

[0141] If only a part of the plurality of circularly polarized wave antenna elements 51 constituting one sequence array is made to operate, sufficient effects of axial ratio improvement cannot be obtained. In the seventh embodiment, since the selected m circularly polarized wave antenna elements constitute one or a plurality of sequence arrays, sufficient effects of axial ratio improvement can be obtained. Also, since the m circularly polarized wave antenna elements 51 are selected so that the number of the first amplifiers 24 required is the least, power consumption can be suppressed.

[0142] The above-described embodiments are examples, and of course, substitution or combination of parts of the configurations shown in different embodiments can be made. The same effects as those brought about by the same configurations of the plurality of embodiments are not mentioned in sequence for each embodiment. Also, the present application is not limited to the above-described embodiments. For example, various changes, improvements, combinations, and the like can be made by those skilled in the art.

Claims

1. An antenna module comprising: a plurality of sections each having an input / output port and a plurality of antenna ports and amplifying a high frequency signal; and a plurality of subarray antennas each including a plurality of circularly polarized wave antenna elements, the plurality of circularly polarized wave antenna elements are respectively connected to any one of the plurality of antenna ports, the plurality of circularly polarized wave antenna elements included in each of the plurality of subarray antennas are arranged in a sequence array for each of the subarray antennas, each of the plurality of sections includes: a distribution combiner that distributes a signal input to a first port to the plurality of antenna ports and combines signals input to each of the plurality of antenna ports and outputs from the first port; and a first amplifier connected between the input / output port and the first port, in any one of the plurality of subarray antennas, the plurality of antenna ports to which the plurality of circularly polarized wave antenna elements included in one subarray antenna are respectively connected are included in one section, each of the plurality of circularly polarized wave antenna elements has two feeding points, each of the plurality of antenna ports is connected to the two feeding points of the circularly polarized wave antenna element via a hybrid circuit, and the plurality of circularly polarized wave antenna elements are excited by the hybrid circuit to have the same rotation direction of the circularly polarized wave radiated in the plurality of subarray antennas.

2. The antenna module according to claim 1, wherein the antenna module further comprises a second amplifier connected between each of the plurality of antenna ports and the distribution combiner.

3. The antenna module according to claim 1 or 2, wherein in any one of the plurality of subarray antennas, when connecting geometric centers of all the circularly polarized wave antenna elements included in one subarray antenna with a number of line segments less than the number of the circularly polarized wave antenna elements and making the total length of the line segments the shortest, the lengths of the plurality of line segments are each below a free space wavelength corresponding to a resonance frequency of the circularly polarized wave antenna elements.

4. The antenna module according to any one of claims 1 to 3, wherein when connecting geometric centers of all the circularly polarized wave antenna elements with a number of line segments less than the number of the circularly polarized wave antenna elements and making the total length of the line segments the shortest, the lengths of the plurality of line segments are each below a free space wavelength corresponding to a resonance frequency of the circularly polarized wave antenna elements.

5. The antenna module according to claim 1, wherein each of the plurality of circularly polarized wave antenna elements overlaps the hybrid circuit when viewed from above.

6. The antenna module according to claim 5, wherein a shape of each of the plurality of circularly polarized wave antenna elements when viewed from above is circular.

7. The antenna module according to any one of claims 1 to 4, wherein each of the plurality of circularly polarized wave antenna elements is a perturbation element. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 8. The antenna module according to any one of claims 1 to 7, wherein The subarray antennas of some of the plurality of subarray antennas are oriented in a different direction than the subarray antennas of at least some other of the plurality of subarray antennas.

9. The antenna module according to any one of claims 1 to 8, wherein In the plurality of subarray antennas, subarray antennas having a different number of circularly polarized wave antenna elements constituting a sequential array are mixed together.

10. An antenna driving method of selecting and driving m circularly polarized wave antenna elements, which is less than M, from among M circularly polarized wave antenna elements in an antenna module having a configuration in which the M circularly polarized wave antenna elements are driven by a plurality of first amplifiers, wherein Any one of the plurality of first amplifiers is configured to drive a plurality of the M circularly polarized wave antenna elements, The M circularly polarized wave antenna elements constitute a plurality of sequential arrays, The m circularly polarized wave antenna elements are selected from among the M circularly polarized wave antenna elements and driven so as to satisfy a condition that the selected m circularly polarized wave antenna elements constitute one or a plurality of sequential arrays and a condition that the number of the first amplifiers required to drive the m circularly polarized wave antenna elements is the least.

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