Measurement system, receiving device, measurement method, and receiving method

Abstract

SOLUTION: A measurement system includes: an output unit which outputs a first radio wave whose polarization direction is the first polarization direction and frequency is a first frequency and a second radio wave whose polarization direction is a second polarization direction being the direction perpendicular to the first polarization direction, and frequency is a second frequency different by a differential frequency from the first frequency; a reflection unit which reflects a composite radio wave of the first radio wave and the second radio wave; a separation unit which functions as an OMT (Ortho Mode Transducer) to separate the composite radio wave reflected by the reflection unit to a first polarization component and a second polarization component; and a measurement unit which measures propagation characteristics of the first radio wave and propagation characteristics of the second radio wave on the basis of the first polarization component and the second polarization component, and a reflection angle when the reflection unit reflects the composite radio wave.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a measurement system, a receiving device, a measurement method, and a receiving method. [Background technology]

[0002] Patent Document 1 describes a measurement system that can measure the propagation characteristics of radio waves with a simple configuration. [Prior art document] [Patent documents] [Patent Document 1] JP 2013-070222 A Summary of the Invention [Means for solving the problem]

[0003] According to an embodiment of the present invention, a measurement system is provided. The measurement system may include an output unit that outputs a first radio wave having a first polarization direction and a first frequency, and a second radio wave having a second polarization direction perpendicular to the first polarization direction and a second frequency that differs from the first frequency by a difference frequency. The measurement system may include a reflector that reflects a composite radio wave of the first radio wave and the second radio wave. The measurement system may include a separator that functions as an OMT (Ortho Mode Transducer) that separates the composite radio wave reflected by the reflector into a first polarization component and a second polarization component. The measurement system may include a measurement unit that measures a propagation characteristic of the first radio wave and a propagation characteristic of the second radio wave based on the first polarization component and the second polarization component and a reflection angle when the reflector reflects the composite radio wave.

[0004] In the measurement system, the output section may output the first radio wave in the first polarization direction, which is a vertical direction, and the second radio wave in the second polarization direction, which is a horizontal direction.

[0005] In any of the measurement systems described above, the output section may output the first radio wave of the first frequency whose frequency is included in the millimeter wave band or the terahertz wave band, and the second radio wave of the second frequency whose frequency is included in the millimeter wave band or the terahertz wave band.

[0006] In any of the measurement systems described above, the reflecting section may reflect the composite radio wave while rotating at a predetermined rotation speed.

[0007] According to one embodiment of the present invention, there is provided a receiving device. The receiving device may include a reflecting unit that reflects a composite radio wave of a first radio wave having a first polarization direction and a first frequency, and a second radio wave having a second polarization direction perpendicular to the first polarization direction and a second frequency that differs from the first frequency by a difference frequency. The receiving device may include an OMT that separates the composite radio wave reflected by the reflecting unit into a first polarization component and a second polarization component, and outputs the first polarization component and the second polarization component to a measuring device that measures a propagation characteristic of the first radio wave and a propagation characteristic of the second radio wave based on the first polarization component and the second polarization component and a reflection angle when the reflecting unit reflects the composite radio wave.

[0008] In the receiving device, the reflecting section may reflect the composite radio wave while rotating at a predetermined rotation speed.

[0009] According to one embodiment of the present invention, there is provided a measurement method executed by a measurement system including an output unit, a reflector, a separator functioning as an OMT, and a measurement unit. The measurement method may include an output step in which the output unit outputs a first radio wave having a first polarization direction and a first frequency, and a second radio wave having a second polarization direction perpendicular to the first polarization direction and a second frequency that differs from the first frequency by a difference frequency. The measurement method may include a reflection step in which the reflector reflects a composite radio wave of the first radio wave and the second radio wave. The measurement method may include a separation step in which the separator separates the composite radio wave reflected in the reflection step into a first polarization component and a second polarization component. The measurement method may include a measurement step in which the measurement unit measures a propagation characteristic of the first radio wave and a propagation characteristic of the second radio wave based on the first polarization component and the second polarization component and a reflection angle when the reflector reflects the composite radio wave.

[0010] According to one embodiment of the present invention, there is provided a receiving method executed by a receiving device including a reflecting unit and an OMT. The receiving method may include a reflecting step in which the reflecting unit reflects a composite radio wave of a first radio wave having a first polarization direction and a first frequency, and a second radio wave having a second polarization direction perpendicular to the first polarization direction and a second frequency that differs from the first frequency by a difference frequency. The receiving method may include a separating step in which the OMT separates the composite radio wave reflected in the reflecting step into a first polarization component and a second polarization component. The receiving method may include an outputting step in which the OMT outputs the first polarization component and the second polarization component to a measuring device that measures a propagation characteristic of the first radio wave and a propagation characteristic of the second radio wave based on the first polarization component and the second polarization component and a reflection angle at which the reflecting unit reflects the composite radio wave in the reflecting step.

[0011] The above summary of the invention does not list all of the necessary features of the present invention. Also, subcombinations of these features may also be inventions. [Brief description of the drawings]

[0012] [Figure 1] An example of a system 10 is shown diagrammatically. [Diagram 2] 1 shows a schematic of an example in which an OMT 150 separates a radio wave into two polarization components. [Diagram 3] 2 illustrates an example of a functional configuration of the receiving device 100. [Figure 4] FIG. 1 is an explanatory diagram for explaining an example of a demonstration experiment for measuring the propagation characteristics of radio waves. [Diagram 5] The measurement results of radio wave propagation characteristics are shown below. [Figure 6] 1 shows an example of a process flow of the system 10. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] It has been reported that the reflection and scattering characteristics of vertically polarized waves (sometimes called V-polarized waves) are different from those of horizontally polarized waves (sometimes called H-polarized waves) in millimeter-wave or terahertz-wave band radio waves. Therefore, when acquiring the propagation characteristics of millimeter-wave or terahertz-wave band radio waves, it is necessary to measure the propagation characteristics of the V-polarized waves and the H-polarized waves, respectively. In the system 10 according to the present embodiment, an OMT is attached to the primary radiator of the rotating reflector antenna to provide a multiport, and a rotation matrix corresponding to the orientation of the rotating reflector is multiplied to the orthogonal two-polarized signal output from the OMT, thereby separately acquiring the V-polarized wave component and the H-polarized wave component of the arriving wave.

[0014] The present invention will be described below through embodiments of the invention, but the following embodiments do not limit the scope of the invention according to the claims. Furthermore, not all of the combinations of features described in the embodiments are necessarily essential to the solution of the invention.

[0015] Fig. 1 illustrates an example of a system 10. The system 10 may include a receiving device 100. The system 10 may include a vector network analyzer (VNA) 20. The system 10 may include an output device 40. Fig. 1 illustrates an example in which the system 10 includes one output device 40. The system 10 may include multiple output devices 40.

[0016] The VNA 20 generates a signal for measuring the propagation characteristics of the radio wave. The VNA 20 causes the output device 40 to output the radio wave carrying the generated signal.

[0017] The output device 40 outputs radio waves. The output device 40 outputs, for example, radio waves carrying a signal generated by the VNA 20. The output device 40 may be an example of an output section.

[0018] The output device 40 outputs, for example, a first radio wave having a first polarization direction and a first frequency, and a second radio wave having a second polarization direction perpendicular to the first polarization direction and a second frequency that differs from the first frequency by a differential frequency. The output device 40 outputs, for example, the first radio wave and the second radio wave simultaneously. The output device 40 outputs, for example, a composite radio wave of the first radio wave and the second radio wave.

[0019] The output device 40 outputs, for example, linearly polarized radio waves whose polarization plane exists in a plane perpendicular to the propagation direction of the radio waves. The output device 40 outputs, for example, a first radio wave in a first polarization direction whose polarization direction is vertical (sometimes referred to as V direction) and a second radio wave in a second polarization direction whose polarization direction is horizontal (sometimes referred to as H direction). Here, the V direction is a direction perpendicular to the earth, and the H direction is a direction parallel to the earth. The output device 40 may output circularly polarized radio waves whose polarization plane rotates around the propagation direction of the radio waves as a central axis. The output device 40 outputs, for example, the first radio wave which is right-handed circularly polarized and the second radio wave which is left-handed circularly polarized.

[0020] The output device 40 outputs, for example, a first radio wave of a first frequency whose frequency is included in the millimeter wave band or the terahertz wave band, and a second radio wave of a second frequency whose frequency is included in the millimeter wave band or the terahertz wave band. The output device 40 outputs, for example, a first radio wave of a first frequency whose frequency is included in the millimeter wave band, and a second radio wave of a second frequency whose frequency is included in the millimeter wave band. The output device 40 outputs, for example, a first radio wave of a first frequency whose frequency is included in the terahertz wave band, and a second radio wave of a second frequency whose frequency is included in the terahertz wave band.

[0021] 1 shows an example in which the output device 40 outputs a composite radio wave 50 of a first radio wave 52 that is linearly polarized and has a polarization direction in the V direction and a frequency of f0, and a second radio wave 54 that is linearly polarized and has a polarization direction in the H direction and a frequency of f1. In this case, if the differential frequency is Δf, then f1=f0+Δf holds. The differential frequency Δf may be set based on the resolution with which the VNA 20 distinguishes between the first radio wave 52 and the second radio wave 54. The value of the differential frequency Δf may be positive or negative.

[0022] The output device 40 may be any device capable of outputting radio waves having frequencies in the millimeter wave band or the terahertz wave band. The output device 40 may be, for example, a dual-polarized antenna. The output device 40 may be, for example, a horn antenna.

[0023] 1 includes a housing 102, a receiving unit 104, a waveguide 106, a base 110, a support unit 112, a reflecting unit 114, a motor 116, a sensor 118, and an OMT 150. The receiving device 100 may further include a control unit not shown in FIG.

[0024] The reflecting unit 114 reflects, for example, the radio wave output by the output device 40. The reflecting unit 114 reflects, for example, the composite radio wave 50.

[0025] The reflecting unit 114 may be any object that can reflect the radio waves output by the output device 40. The reflecting unit 114 may be, for example, a reflecting mirror. The reflecting unit 114 may be, for example, a reflecting plate.

[0026] The shape of the reflector 114 may be any shape as long as it can reflect the radio waves output by the output device 40. The reflector 114 is, for example, in a parabolic shape. The reflector 114 may also be in the shape of a plate.

[0027] The reflecting section 114 reflects the composite radio wave 50 while rotating at a predetermined rotation speed, for example. The reflecting section 114 may reflect the composite radio wave 50 while stationary.

[0028] The control unit executes various controls. For example, the control unit controls the angle of the reflecting unit 114. For example, the control unit controls the angle of the reflecting unit 114 by rotating the base 110 using the motor 116 to rotate the reflecting unit 114 supported by the support unit 112 fixed to the base 110. The rotating reflector antenna may be an example of the receiving device 100.

[0029] The control unit may grasp the angle of the reflecting unit 114 based on the control amount of the motor 116. The control unit may grasp the angle of the reflecting unit 114 using a sensor 118.

[0030] The receiving unit 104 receives radio waves whose frequencies are included in the millimeter wave band or the terahertz wave band. The receiving unit 104 receives, for example, radio waves reflected by the reflecting unit 114. The radio waves received by the receiving unit 104 are input to the OMT 150 via the waveguide 106.

[0031] The receiving unit 104 may be any member capable of receiving radio waves having frequencies in the millimeter wave band or the terahertz wave band, and is, for example, a horn antenna.

[0032] The OMT 150 has a function of splitting a radio wave into two orthogonal linearly polarized components. For example, the OMT 150 splits the composite radio wave 50 into a first polarized component and a second polarized component. The OMT 150 may be an example of a splitter.

[0033] The OMT 150 may output two polarized components of the separated radio waves as I / Q (In-Phase / Quadrature-Phase) signals. Here, it is assumed that the polarized component of the radio waves that the OMT 150 outputs to the X port 152 is a first polarized component, and the polarized component of the radio waves that the OMT 150 outputs to the Y port 154 is a second polarized component. In this case, the first polarized component corresponds to the X port 152, and the second polarized component corresponds to the Y port 154. The VNA 20 may receive the two polarized components output by the OMT 150.

[0034] The VNA 20 measures the propagation characteristics of radio waves. The VNA 20 measures, for example, the propagation characteristics of the first radio wave 52 and the propagation characteristics of the second radio wave 54. The VNA 20 simultaneously measures, for example, the propagation characteristics of the first radio wave 52 and the propagation characteristics of the second radio wave 54. The VNA 20 measures, for example, the propagation characteristics of the first radio wave 52 and the propagation characteristics of the second radio wave 54 based on the first polarization component and the second polarization component of the composite radio wave 50 separated by the OMT 150 and the reflection angle at which the reflecting unit 114 reflects the composite radio wave 50. The VNA 20 may be an example of a measuring unit. The VNA 20 may be an example of a measuring device.

[0035] The propagation characteristics of the radio waves include, for example, the electric field strength of the radio waves. The propagation characteristics of the radio waves include, for example, the direction in which the radio waves arrive at the reflecting unit 114. The propagation characteristics of the radio waves may include the amount of attenuation of the radio waves until they arrive at the reflecting unit 114.

[0036] In the example of the system 10 shown in FIG. 1, the propagation characteristics of the radio waves may be measured using a signal generator (SG) and a spectrum analyzer (SA) capable of acquiring I / Q signals in synchronization with transmission and reception of the radio waves.

[0037] Fig. 2 is a schematic diagram showing an example in which the OMT 150 separates a radio wave into two polarized components. Fig. 2 shows an example in which the OMT 150 separates the composite radio wave 50 shown in Fig. 1 into a first polarized component and a second polarized component. Here, the reflection angle when the reflector 114 reflects the composite radio wave 50 is assumed to be φ.

[0038] 2A is a schematic diagram showing an example in which the OMT 150 separates the composite radio wave 50 into a first polarization component and a second polarization component when φ=0°. As shown in FIG. 2A, the OMT 150 outputs the first radio wave 52 to the X port 152 and outputs the second radio wave 54 to the Y port 154. Therefore, in the example shown in FIG. 2A, the first polarization component of the composite radio wave 50 separated by the OMT 150 is the first radio wave 52, and the second polarization component of the composite radio wave 50 separated by the OMT 150 is the second radio wave 54.

[0039] 2B is a schematic diagram showing an example in which the OMT 150 separates the composite radio wave 50 into a first polarization component and a second polarization component when φ=90°. As shown in FIG. 2B, the OMT 150 outputs the second radio wave 54 to the X port 152 and outputs the first radio wave 52 to the Y port 154. Therefore, in the example shown in FIG. 2B, the first polarization component of the composite radio wave 50 separated by the OMT 150 is the second radio wave 54, and the second polarization component of the composite radio wave 50 separated by the OMT 150 is the first radio wave 52.

[0040] 2A and 2B, the polarization components of the composite radio wave 50 output by the OMT 150 to the X port 152 and the Y port 154 respectively differ depending on the reflection angle when the reflector 114 reflects the composite radio wave 50. Therefore, in order for the VNA 20 to measure the propagation characteristics of the first radio wave 52 and the second radio wave 54 from the first polarization component and the second polarization component of the composite radio wave 50, it is necessary to derive the first radio wave 52 and the second radio wave 54, respectively, from the first polarization component and the second polarization component of the composite radio wave 50 and the reflection angle when the reflector 114 reflects the composite radio wave 50. Therefore, when the first polarization component and the second polarization component of the composite radio wave 50 are each E X (φ) and E Y If the reflection angle when the reflector 114 reflects the composite radio wave 50 is φ, the VNA 20 calculates E according to the following formula: X (φ) and E Y By multiplying (φ) by the inverse of the rotation matrix of φ, the electric field strength E V (φ) and the electric field strength E of the second radio wave 54 H Derive (φ).

[0041]

number

[0042] For example, when φ=0° as shown in FIG. 2A, the VNA 20 calculates E V (0°)=cos0°×E X (0°)+sin0°×E Y (0°)=E X (0°) and E H (0°)=-sin0°×E X (0°) + cos0° × E Y (0°)=E Y In addition, when φ=90° as shown in FIG. 2B, the VNA 20 derives E V (90°)=cos90°×E X (90°)+sin90°×E Y (90°)=EY (90°) and E H (90°)=-sin90°×E X (90°) + cos90° × E Y (90°)=-E X (90°) are derived respectively.

[0043] It is being considered that radio waves having a frequency in the millimeter wave band or terahertz wave band will be used in mobile communications beyond 5G (5th Generation) communications and 6G (6th Generation) communications and beyond. Therefore, it is becoming important to measure the propagation characteristics of radio waves having a frequency in the millimeter wave band or terahertz wave band. When measuring the propagation characteristics of radio waves having a frequency in the millimeter wave band or terahertz wave band, a cable cannot be used, and a planar antenna for radio waves having a frequency in the millimeter wave band or terahertz wave band has not been developed, so that currently, a method of measuring the arrival direction of radio waves by rotating an aperture antenna is mainstream. However, since the aperture antenna cannot be rotated at high speed, this method has an issue in that it takes a long measurement time. In particular, when measuring the arrival direction of two polarized radio waves, V-polarized radio waves and H-polarized radio waves, with this method, the polarization direction must be changed and measurements must be taken twice, so this method requires even more measurement time.

[0044] In contrast, according to the system 10 of the present embodiment, the VNA 20 outputs to the output device 40 a composite radio wave 50 of two radio waves, a first radio wave 52 and a second radio wave 54, which have different frequencies and are polarized in directions perpendicular to each other. Then, the receiving device 100 uses the OMT 150 to separate the composite radio wave 50 reflected by the reflecting section 114 rotating at a predetermined speed into two polarized components and outputs them to the VNA 20. After that, the VNA 20 measures the propagation characteristics of the first radio wave 52 and the second radio wave 54 based on the first polarized component and the second polarized component of the composite radio wave 50 separated by the OMT 150 and the reflection angle at which the reflecting section 114 reflects the composite radio wave 50. The system 10 of the present embodiment measures the propagation characteristics of radio waves in the millimeter wave band or terahertz wave band while rotating the reflecting section 114, which can rotate at a higher speed than the aperture antenna, and therefore can shorten the measurement time of the propagation characteristics of radio waves in the millimeter wave band or terahertz wave band compared to the conventional method. Furthermore, the system 10 according to the present embodiment can simultaneously measure the propagation characteristics of the first radio wave 52 and the second radio wave 54 from the polarization components of the two radio waves separated by the OMT 150, regardless of the reflection angle when the reflecting unit 114 reflects the composite radio wave 50. Therefore, compared with a conventional method in which the polarization direction of the radio wave must be changed and measurements must be taken twice to measure the propagation characteristics of dual-polarized radio waves, the measurement time for the propagation characteristics of radio waves having a frequency in the millimeter wave band or the terahertz wave band can be further shortened. In addition, when measuring dual polarized waves simultaneously, the system 10 according to the present embodiment simultaneously measures the propagation characteristics of the first radio wave 52 and the propagation characteristics of the second radio wave 54 after changing the frequency of the second radio wave 54 by only the difference frequency with respect to the frequency of the first radio wave 52 so that the cross-polarized wave of one polarized wave (e.g., V-polarized wave) does not affect the other polarized wave (e.g., H-polarized wave). As a result, the system 10 of this embodiment can simultaneously measure the propagation characteristics of the first radio wave 52 and the second radio wave 54 without being affected by cross-polarized waves, which is one factor that reduces the measurement accuracy of the propagation characteristics of radio waves, and can therefore simultaneously measure the propagation characteristics of the first radio wave 52 and the second radio wave 54 with high measurement accuracy.

[0045] 3 illustrates an example of a functional configuration of the receiving device 100. The receiving device 100 may include a base 110, a reflecting unit 114, a motor 116, a control unit 117, a sensor 118, a transmitting unit 119, a measuring unit 120, and an OMT 150. It is not essential that the receiving device 100 includes all of these components.

[0046] The control unit 117 executes various controls. For example, the control unit 117 controls the angle of the reflecting unit 114. For example, the control unit 117 controls the angle of the reflecting unit 114 by rotating the base 110 using the motor 116 to rotate the reflecting unit 114.

[0047] The control unit 117, for example, rotates the reflecting unit 114 continuously. The control unit 117 rotates the reflecting unit 114 continuously at a constant rotation speed. The control unit 117 may rotate the reflecting unit 114 continuously rather than at a constant rotation speed. The control unit 117 may rotate the reflecting unit 114 discontinuously. The control unit 117 may rotate the reflecting unit 114 in response to an instruction received from an external device such as the VNA 20.

[0048] The control unit 117 grasps the angle of the reflecting unit 114 based on, for example, the control amount of the motor 116. The control unit 117 may grasp the angle of the reflecting unit 114 using a sensor 118.

[0049] The sensor 118 may be any type as long as it can identify the angle of the reflecting unit 114. For example, the sensor 118 may be a sensor capable of measuring the amount of rotation of the base 110. Furthermore, for example, the sensor 118 may be a sensor capable of identifying the angle of the reflecting unit 114 by capturing an image of the base 110 or the reflecting unit 114.

[0050] When the control unit 117 rotates the reflecting unit 114 at a constant rotation speed, the sensor 118 may be a laser output unit and a laser detection unit arranged at positions facing each other across the base 110. For example, the laser output unit is arranged to output a laser between the housing 102 and the base 110, and the laser detection unit is arranged to detect the laser output, and a tab arranged on a part of the base 110 blocks the laser once every time the base 110 rotates. The control unit 117 can grasp the rotation period by the sensor 118, and therefore the angle of the reflecting unit 114.

[0051] The transmitting unit 119 transmits various information. For example, the transmitting unit 119 transmits various information to the VNA 20. The transmitting unit 119 may transmit various information to other external devices.

[0052] The transmitting unit 119 transmits, for example, reflection angle information indicating a reflection angle when the reflecting unit 114 reflects the composite radio wave 50 output by the output device 40. The transmitting unit 119 may transmit, for example, sensor information detected by the sensor 118.

[0053] For example, the OMT 150 separates the radio wave reflected by the reflector 114 into two linearly polarized components. For example, the OMT 150 separates the composite radio wave 50 into a first polarized component and a second polarized component. The OMT 150 may output the separated first polarized component and second polarized component to the VNA 20.

[0054] The measurement unit 120 measures the propagation characteristics of radio waves. For example, the measurement unit 120 measures the propagation characteristics of radio waves whose frequencies are included in the millimeter wave band or the terahertz wave band.

[0055] The measurement unit 120 measures, for example, the propagation characteristics of radio waves whose polarization direction is the V direction and the propagation characteristics of radio waves whose polarization direction is the H direction. The measurement unit 120 simultaneously measures, for example, the propagation characteristics of radio waves whose polarization direction is the V direction and the propagation characteristics of radio waves whose polarization direction is the H direction.

[0056] The measurement unit 120 measures the propagation characteristics of the first radio wave 52 and the second radio wave 54, for example, based on the first polarization component and the second polarization component of the composite radio wave 50 separated by the OMT 150 and the reflection angle at which the reflector 114 reflects the composite radio wave 50. The transmission unit 119 may transmit the measurement result of the propagation characteristics of the radio waves measured by the measurement unit 120 to an external device.

[0057] The receiving device 100 does not necessarily have to include the measuring unit 120. In this case, an external device such as the VNA 20 may measure the propagation characteristics of the radio wave.

[0058] 4 is an explanatory diagram for explaining an example of a demonstration experiment for measuring the propagation characteristics of radio waves. Here, the propagation characteristics of radio waves are measured using two output devices 42 and 44 having the same functions as the output device 40.

[0059] In the example of the demonstration experiment shown in Fig. 4, the reflecting unit 114 rotates at a rotation speed of 10 rpm (rotations per minute). Therefore, in the example of the demonstration experiment shown in Fig. 4, the measurement time for measuring the propagation characteristics of the radio waves around the receiving device 100 once is about 6 seconds.

[0060] In one example of a demonstration experiment shown in Fig. 4, the output device 42, the output device 44, and the receiving device 100 are arranged in a space surrounded by a radio wave absorber 80. Also, as shown in Fig. 4, the output device 42 is arranged so that the radio waves output from the output device 42 reach the receiving device 100 in a direction of -45°, and the output device 44 is arranged so that the radio waves output from the output device 44 reach the receiving device 100 in a direction of 15°.

[0061] 4, the VNA 20 may output V-polarized radio waves having a frequency of 30.0 GHz to each of the output devices 42 and 44, and may output H-polarized radio waves having a frequency of 30.1 GHz to each of the output devices 42 and 44. In this case, the difference frequency Δf is 0.1 GHz.

[0062] The electric field strength of the radio waves output by each of output device 42 and output device 44 may be different. In one example of a demonstration experiment shown in Fig. 4, the electric field strength of the H-polarized radio waves output by output device 42 is attenuated by 3 dB with respect to the electric field strength of the V-polarized radio waves output by output device 42 by a 3 dB ATT (Attenuator), the electric field strength of the V-polarized radio waves output by output device 44 is attenuated by 6 dB with respect to the electric field strength of the V-polarized radio waves output by output device 42 by a 6 dB ATT, and the electric field strength of the H-polarized radio waves output by output device 44 is attenuated by 10 dB with respect to the electric field strength of the V-polarized radio waves output by output device 42 by a 10 dB ATT.

[0063] Fig. 5 illustrates the measurement results of the propagation characteristics of radio waves. Fig. 5 illustrates the measurement results of the propagation characteristics of the V-polarized radio waves output by each of the output devices 42 and 44, and the propagation characteristics of the H-polarized radio waves output by each of the output devices 42 and 44 in the example of the demonstration experiment shown in Fig. 4.

[0064] The horizontal axis of the graph shown in FIG. 5 is the reflection angle φ [°] when the reflector 114 reflects the radio wave, and the vertical axis of the graph shown in FIG. 5 is the electric field strength [dB] of the radio wave measured by the VNA 20.

[0065] Fig. 5(A) illustrates the measurement results of the propagation characteristics of radio waves with a frequency of 30.0 GHz. The "●" in the graph of Fig. 5(A) is a simulation result obtained by simulating the propagation characteristics of 30.0 GHz V-polarized radio waves in the experimental environment of the demonstration experiment shown in Fig. 4. The simulation result shows that when φ=-45°, a V-polarized radio wave of 0 dB output by output device 42 arrives at receiving device 100, and when φ=15°, a V-polarized radio wave of -6 dB output by output device 44 arrives at receiving device 100.

[0066] The solid line in graph (A) of Figure 5 shows the measurement results of the propagation characteristics of V-polarized radio waves with a frequency of 30.0 GHz. The dotted line in graph (A) of Figure 5 shows the measurement results of the propagation characteristics of H-polarized radio waves with a frequency of 30.0 GHz, which are cross-polarized waves of the V-polarized radio waves with a frequency of 30.0 GHz.

[0067] As shown in the graph of FIG. 5A, the measurement results of the propagation characteristics of the V-polarized radio waves are highly consistent with the simulation results. Moreover, the H-polarized radio waves shown in the graph of FIG. 5A are the propagation characteristics of the cross-polarized radio waves transmitted with the V-polarized waves. That is, it is also possible to measure the amount of polarization rotation of the radio waves transmitted with the V-polarized waves. This measurement result shows that the orthogonality of the polarization of the radio waves arriving at the receiving device 100 is maintained because the electric field strength of the H-polarized radio waves is sufficiently small compared to the electric field strength of the V-polarized radio waves. Note that the electric field strength of the H-polarized radio waves, which are the cross-polarized waves of the V-polarized radio waves output by the output device 44, is smaller than the electric field strength of the V-polarized radio waves output by the output device 42 by 20 dB, and is therefore not shown in the graph of FIG. 5A.

[0068] Fig. 5B illustrates the measurement results of the propagation characteristics of radio waves with a frequency of 30.1 GHz. The "■" in the graph of Fig. 5B is a simulation result obtained by simulating the propagation characteristics of 30.1 GHz H-polarized radio waves in the experimental environment of the demonstration experiment shown in Fig. 4. The simulation result shows that when φ=-45°, H-polarized radio waves of -3 dB output by output device 42 arrive at receiving device 100, and when φ=15°, H-polarized radio waves of -10 dB output by output device 44 arrive at receiving device 100.

[0069] The dotted line in graph (B) of Figure 5 shows the measurement results of the propagation characteristics of H-polarized radio waves with a frequency of 30.1 GHz. The solid line in graph (B) of Figure 5 shows the measurement results of the propagation characteristics of V-polarized radio waves with a frequency of 30.1 GHz, which are cross-polarized waves of the H-polarized radio waves with a frequency of 30.1 GHz.

[0070] As shown in the graph of FIG. 5B, the measurement results of the propagation characteristics of the radio waves of H polarization are highly consistent with the simulation results. Moreover, the radio waves of V polarization shown in the graph of FIG. 5B are the propagation characteristics of the cross-polarized radio waves transmitted by H polarization. That is, it is also possible to measure the amount of polarization rotation of the radio waves transmitted by H polarization. This measurement result shows that the orthogonality of the polarization of the radio waves arriving at the receiving device 100 is maintained because the electric field strength of the radio waves of V polarization is sufficiently small compared to the electric field strength of the radio waves of H polarization. Note that the electric field strength of the radio waves of V polarization, which are the cross-polarized waves of the radio waves of H polarization output by the output device 44, is smaller than the electric field strength of the radio waves of V polarization output by the output device 42 by 20 dB, and is therefore not shown in the graph of FIG. 5B.

[0071] From the measurement results of the radio wave propagation characteristics illustrated in FIG. 5, it can be said that in the example of the demonstration experiment shown in FIG. 4, the propagation characteristics of the V-polarized radio waves output by each of output devices 42 and 44, and the propagation characteristics of the H-polarized radio waves output by each of output devices 42 and 44 were measured with high accuracy in a short measurement time of approximately 6 seconds.

[0072] 6 is a schematic diagram showing an example of a processing flow by the system 10. Here, a case where the reflecting unit 114 is continuously rotating at a constant speed will be taken as an example, and a state where the output device 40 is not outputting the composite radio wave 50 will be taken as a starting state.

[0073] In step (step may be abbreviated as S) 102, the output device 40 outputs a composite radio wave 50 of the first radio wave 52 and the second radio wave 54. In S104, the receiving device 100 receives the composite radio wave 50 reflected by the reflecting section 114 at the receiving section 104. The composite radio wave 50 received at the receiving section 104 is input to the OMT 150 via the waveguide 106. The OMT 150 separates the input composite radio wave 50 into a first polarization component and a second polarization component.

[0074] In S106, the OMT 150 outputs the first polarized wave component and the second polarized wave component of the composite radio wave 50 separated in S104 to the VNA 20. In addition, the transmitting unit 119 transmits the reflection angle information to the VNA 20.

[0075] In S108, the VNA 20 measures the propagation characteristics of the first radio wave 52 and the propagation characteristics of the second radio wave 54 based on the first polarization component and the second polarization component of the composite radio wave 50 output by the OMT 150 in S106 and the reflection angle at which the reflecting unit 114 reflects the composite radio wave 50, which is indicated by the reflection angle information transmitted by the transmitting unit 119 in S106.

[0076] Although the present invention has been described above using the embodiments, the technical scope of the present invention is not limited to the scope described in the above embodiments. It is clear to those skilled in the art that various modifications and improvements can be made to the above embodiments. It is clear from the description of the claims that such modifications and improvements can also be included in the technical scope of the present invention.

[0077] It should be noted that the order of execution of each process, such as operations, procedures, steps, and stages, in the devices, systems, programs, and methods shown in the claims, specifications, and drawings is not specifically stated as "before" or "prior to," and that the process may be performed in any order unless the output of a previous process is used in a later process. Even if the operational flow in the claims, specifications, and drawings is described using "first," "next," etc. for convenience, it does not mean that the process must be performed in this order. [Explanation of symbols]

[0078] 10 system, 20 VNA, 40 output device, 42 output device, 44 output device, 50 composite radio wave, 52 first radio wave, 54 second radio wave, 80 radio wave absorber, 100 receiving device, 102 housing, 104 receiving unit, 106 waveguide, 110 base, 112 support unit, 114 reflecting unit, 116 motor, 117 control unit, 118 sensor, 119 transmitting unit, 120 measuring unit, 150 OMT, 152 X port, 154 Y port

Claims

1. an output unit that outputs a first radio wave having a first polarization direction and a first frequency, and a second radio wave having a second polarization direction perpendicular to the first polarization direction and a second frequency different from the first frequency; a reflecting section that reflects a composite radio wave of the first radio wave and the second radio wave; a separation unit that functions as an OMT (Ortho Mode Transducer) that separates the composite radio wave reflected by the reflection unit into a first polarized wave component and a second polarized wave component; a measurement unit that measures a propagation characteristic of the first radio wave and a propagation characteristic of the second radio wave based on the first polarized wave component and the second polarized wave component and a reflection angle when the reflector reflects the composite radio wave; Equipped with The measurement unit derives the propagation characteristics of the first radio wave and the propagation characteristics of the second radio wave by multiplying the first polarization component and the second polarization component by an inverse matrix of a rotation matrix of the reflection angle according to the following formula: [0010] Here, E X (φ) is the first polarized wave component, E Y (φ) is the second polarized wave component, φ is the reflection angle, E V (φ) is the electric field strength of the first radio wave, and E H (φ) is the electric field strength of the second radio wave. Measurement system.

2. The measurement system according to claim 1 , wherein the output unit outputs the first radio wave in the first polarization direction, which is a vertical direction, and the second radio wave in the second polarization direction, which is a horizontal direction.

3. 3. The measurement system according to claim 1, wherein the output unit outputs the first radio wave of the first frequency, the frequency of which is included in a millimeter wave band or a terahertz wave band, and the second radio wave of the second frequency, the frequency of which is included in a millimeter wave band or a terahertz wave band.

4. A control unit that controls the angle of the reflecting part by rotating the base with a motor to rotate the reflecting part supported by a support part fixed to the base. Further equipped with The measurement system according to claim 1 , wherein the reflecting section reflects the composite radio wave while rotating at a predetermined rotation speed.

5. a reflecting section that reflects a composite radio wave of a first radio wave having a first polarization direction and a first frequency, and a second radio wave having a second polarization direction perpendicular to the first polarization direction and a second frequency different from the first frequency; an OMT that separates the composite radio wave reflected by the reflector into a first polarized wave component and a second polarized wave component; a measurement unit that measures a propagation characteristic of the first radio wave and a propagation characteristic of the second radio wave based on the first polarization component and the second polarization component separated by the OMT and a reflection angle when the reflector reflects the composite radio wave; Equipped with The measurement unit derives the propagation characteristics of the first radio wave and the propagation characteristics of the second radio wave by multiplying the first polarization component and the second polarization component by an inverse matrix of a rotation matrix of the reflection angle according to the following formula: [0025] Here, E X (φ) is the first polarized wave component, E Y (φ) is the second polarized wave component, φ is the reflection angle, E V (φ) is the electric field strength of the first radio wave, and E H (φ) is the electric field strength of the second radio wave. Receiving device.

6. A control unit that controls an angle of the reflecting part by rotating the base with a motor to rotate the reflecting part supported by a support part fixed to the base. Further equipped with The reflecting unit reflects the composite radio wave while rotating at a predetermined rotation speed.

6. The receiving device according to claim 5.

7. A measurement method performed by a measurement system including an output section, a reflecting section, a separating section functioning as an OMT, and a measurement section, comprising: an output step in which the output unit outputs a first radio wave having a first polarization direction and a first frequency, and a second radio wave having a second polarization direction perpendicular to the first polarization direction and a second frequency different from the first frequency; a reflecting step in which the reflector reflects a composite radio wave of the first radio wave and the second radio wave; a separating step in which the separating unit separates the composite radio wave reflected in the reflecting step into a first polarized wave component and a second polarized wave component; a measurement step in which the measurement unit measures a propagation characteristic of the first radio wave and a propagation characteristic of the second radio wave based on the first polarization component and the second polarization component and a reflection angle when the reflection unit reflects the composite radio wave; Equipped with The measuring step derives a propagation characteristic of the first radio wave and a propagation characteristic of the second radio wave by multiplying the first polarization component and the second polarization component by an inverse matrix of a rotation matrix of the reflection angle according to the following formula: [0030] Here, E X (φ) is the first polarized wave component, E Y (φ) is the second polarized wave component, φ is the reflection angle, E V (φ) is the electric field strength of the first radio wave, and E H (φ) is the electric field strength of the second radio wave. Measurement method.

8. A receiving method performed by a receiving device including a reflector, an OMT, and a measuring unit, comprising: a reflecting step in which the reflecting unit reflects a composite radio wave of a first radio wave having a first polarization direction and a first frequency, and a second radio wave having a second polarization direction perpendicular to the first polarization direction and a second frequency different from the first frequency; a separating step of separating the composite radio wave reflected in the reflecting step by the OMT into a first polarization component and a second polarization component; a measurement step in which the measurement unit measures a propagation characteristic of the first radio wave and a propagation characteristic of the second radio wave based on the first polarization component and the second polarization component separated by the OMT and a reflection angle when the reflector reflects the composite radio wave in the reflection step, The measuring step derives a propagation characteristic of the first radio wave and a propagation characteristic of the second radio wave by multiplying the first polarization component and the second polarization component by an inverse matrix of a rotation matrix of the reflection angle according to the following formula: [0045] Here, E X (φ) is the first polarized wave component, E Y (φ) is the second polarized wave component, φ is the reflection angle, E V (φ) is the electric field strength of the first radio wave, and E H (φ) is the electric field strength of the second radio wave. Receiving method.

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