Test apparatus and test method

Abstract

A test apparatus and test method are disclosed. The test apparatus measures the transmission or reception characteristics of a device under test (DUT) with an antenna under test. The test apparatus includes: an anechoic chamber; a posture-variable mechanism (56) that sequentially changes the posture of the DUT disposed in a blank area within the anechoic chamber; a first test antenna (6a) and a second test antenna (6b) housed in an internal space and transmitting or receiving wireless signals for measuring the transmission or reception characteristics of the DUT between the first test antenna and the antenna under test; a reflector that reflects the wireless signals emitted by the first test antenna and converts them into plane wave wireless signals; and an antenna movable mechanism (60) that moves the position of the second test antenna in such a way that it can transmit or receive wireless signals to the DUT disposed in the far field at multiple arrival angles or multiple transmission angles, based on the direction of arrival of the radio waves from the first test antenna or the direction of transmission of the radio waves from the first test antenna.

Description

Technical Field

[0001] This invention relates to a test apparatus and test method for measuring the transmission or reception characteristics of a test object using an anechoic chamber in an OTA (Over The Air) environment. Background Technology

[0002] In recent years, with the development of multimedia, a large number of wireless terminals (such as smartphones) equipped with antennas for wireless communication, such as cellular and wireless LAN, have been produced. In the future, there will be a particular demand for wireless terminals that can transmit and receive broadband signals in the millimeter wave band, such as those corresponding to IEEE 802.11ad or 5G cellular signals.

[0003] In the design and development companies or manufacturing plants of wireless terminals, the output level and receiving sensitivity of the transmitted radio waves of the wireless communication antennas equipped with the wireless terminals are measured according to the settings of each communication standard, and performance tests are conducted to determine whether these RF (Radio Frequency) characteristics meet the specified benchmarks. Furthermore, RRM (Radio Resource Management) characteristics are also measured during the performance tests. RRM characteristic measurements are performed to confirm whether radio resource control between the base station and the wireless terminal, such as handover between adjacent base stations, is functioning correctly.

[0004] With the transition from 4G to 5G, the testing methods for the aforementioned performance tests are also changing. For example, in performance tests using a wireless terminal as the device under test (DUT) in a 5G NR (New Radio) system, the conventional method of connecting the antenna terminals of the DUT to the test apparatus via wired connection, which is the mainstream method used in 4G or 4G evolution tests, is unusable for several reasons: characteristic degradation caused by installing antenna terminals in high-frequency circuits, and the large number of components in the array antenna and the impracticality of installing antenna terminals on all components due to space and cost considerations. Therefore, the DUT and the test antenna are housed together in an anechoic chamber unaffected by the surrounding radio wave environment, and the test signal is transmitted from the test antenna to the DUT and the measured signal from the DUT that has received the test signal is received by the test antenna, thus performing what is known as OTA testing (for example, see Patent Document 1).

[0005] In OTA testing, the test antenna, positioned within an anechoic chamber, forms, for example, a spherical quiet zone, within which the DUT is positioned. Here, the quiet zone refers to the area within the anechoic chamber constituting the OTA testing environment that is illuminated by radio waves from the test antenna with approximately uniform amplitude and phase (see, for example, Non-Patent Document 1). By positioning the DUT within this quiet zone, OTA testing can be performed while suppressing the effects of scattered waves from the surrounding environment.

[0006] Patent Document 1: Japanese Patent Application Publication No. 2020-085784

[0007] Non-patent literature 1: 3GPP TR 38.810

[0008] Figure 16 This is a top view taken from above, after the top plate of the anechoic chamber of a previous test apparatus for measuring the RRM characteristics of the DUT has been removed.

[0009] Conventional test setups include a reflector-reflecting test antenna 206a that transmits and receives radio waves via a reflector 207 and a DUT 100, and test antennas 206b, 206c, 206d, 206e, and 206f that transmit and receive radio waves via the DUT 100. These five test antennas 206b, ..., 206f are configured at the DUT 100's location (origin O) to form five different arrival angles (30°, 60°, 90°, 120°, and 150°) based on the direction of arrival of radio waves from the reflector-reflecting test antenna 206a. During testing, two test antennas selected from 206a, ..., 206f are used to measure transmit and receive characteristics, such as RRM characteristics, at different arrival angles. However, a large number of test antennas increases the cost of the setup or installation; therefore, it is desirable to reduce the number of test antennas. Summary of the Invention

[0010] This invention was made to solve this previous problem, and its purpose is to provide a test apparatus and test method that can perform far-field measurements of the RRM characteristics and other transceiver characteristics of the test object with a smaller number of antennas.

[0011] To address the aforementioned issues, the present invention relates to a test apparatus for measuring the transmission or reception characteristics of a test object (100) having a test antenna (110). The test apparatus (1) has the following structure: it comprises: an anechoic chamber (50) having an internal space unaffected by the surrounding radio wave environment; a posture-variable mechanism (56) for sequentially changing the posture of the test object disposed within a blank area (QZ) in the internal space; a first test antenna (6a) and a second test antenna (6b) housed within the internal space and positioned relative to the test object. The test antennas transmit or receive wireless signals for measuring the transmission or reception characteristics of the test object; a reflector (7) reflects the wireless signals emitted by the first test antenna and converts them into plane wave wireless signals; and an antenna movable mechanism (60) moves the position of the second test antenna in such a way that it can transmit or receive wireless signals to the test object located in the far field at multiple arrival angles or multiple transmission angles with reference to the direction of arrival of the radio waves from the first test antenna or the direction of emission of the radio waves from the first test antenna.

[0012] As described above, the test apparatus according to this embodiment includes an antenna movable mechanism that allows the position of the second test antenna to be moved so as to transmit or receive wireless signals to a test object located in the far field at multiple arrival angles or multiple transmission angles, based on the direction of arrival of radio waves from the first test antenna or the direction of transmission of radio waves from the first test antenna. According to this structure, in far-field measurements of the transceiver characteristics such as the RRM characteristics of the test object, it is not necessary to set up test antennas according to the number of arrival angles for testing, thereby reducing the number of antennas. This reduces the cost of equipment such as antennas and installation work.

[0013] Furthermore, in the test apparatus of the present invention, the structure may be such that the antenna movable mechanism includes an antenna holding part (600) for holding the second test antenna and a moving mechanism (700) for moving the antenna holding part in a circle.

[0014] According to this structure, the test apparatus involved in the present invention can not only reduce the number of antennas, but also keep the distance between the second test antenna and the test object constant even if the angle of arrival is different.

[0015] Furthermore, in the test apparatus of the present invention, the structure may be such that the antenna holding part has a columnar support (61) for holding the second test antenna, and the support is inclined relative to the vertical direction such that one end of the moving mechanism is mounted closer to the central axis of the circle than the other end.

[0016] According to this structure, the experimental device involved in the present invention can reduce the area and space occupied by the movable mechanism of the antenna, thereby making effective use of the limited internal space of the anechoic chamber.

[0017] Furthermore, the test apparatus according to the present invention may have the following structure: it also includes a reflector (9) that reflects the wireless signal emitted from the second test antenna and transmits it to the antenna under test, and reflects the wireless signal emitted from the antenna under test and transmits it to the second test antenna, and the antenna holding part holds the second test antenna and the reflector at intervals in the length direction.

[0018] According to this structure, the test apparatus of the present invention can change the path of the wireless signals transmitted and received between the second test antenna and the antenna under test by means of a reflector, so that the distance between antennas required for far-field measurement can be ensured even in the limited internal space of the anechoic chamber.

[0019] Furthermore, in the experimental apparatus involved in this invention, the structure may be as follows: the moving mechanism includes a linear motion part (701) for linearly moving the moving stage (72), an arc-shaped guide rail (76), a movable stage (77) for which the antenna holding part is fixed and can move along the guide rail, and a connecting rod (703) for connecting the moving stage and the movable stage and for moving the movable stage along the guide rail by the linear movement of the moving stage. The connecting rod is connected to the moving stage in such a way that the length direction of the connecting rod is always orthogonal to the moving direction of the moving stage.

[0020] According to this structure, the test apparatus of the present invention can reduce the number of antennas by eliminating the need to set up test antennas according to the number of arrival angles for the test, and can set up a second test antenna in a manner that allows for any arrival angle within a specified range. Furthermore, by avoiding the attitude-variable mechanism that holds the test object at its center within the anechoic chamber, the movable antenna mechanism can be placed around the periphery, thereby effectively utilizing the limited internal space of the anechoic chamber.

[0021] Furthermore, in the experimental apparatus of the present invention, the structure may be as follows: the moving mechanism includes a linear motion part (701) for linearly moving the moving stage (72), an arc-shaped guide rail (76), a movable stage (77) for which the antenna holding part is fixed and can move along the guide rail, and a connecting rod (703) for connecting the moving stage and the movable stage and for moving the movable stage along the guide rail by the linear movement of the moving stage. The connecting rod is connected to the moving stage in such a way that the angle formed by the length direction of the connecting rod relative to the moving direction of the moving stage changes according to the position of the moving stage.

[0022] According to this structure, the test apparatus of the present invention can shorten the length of the linear motion section, thereby effectively utilizing the limited internal space of the anechoic chamber by avoiding the posture-variable mechanism that holds the center of the test object within the anechoic chamber.

[0023] Furthermore, in the experimental apparatus involved in the present invention, the structure may be as follows: the moving mechanism includes a ring-shaped or arc-shaped rack (81) with a plurality of teeth formed on the inner or outer circumferential surface, a pinion (82) having a gear that engages with the teeth of the rack and moving along the rack by rotating via a rotation drive unit, and a movable stage (84) mounted on the pinion, wherein the antenna holding part is mounted on the movable stage.

[0024] According to this structure, the test apparatus of the present invention can place the movable antenna mechanism on the periphery of the anechoic chamber, avoiding the attitude-variable mechanism that holds the test object in the center, thereby effectively utilizing the limited internal space of the anechoic chamber.

[0025] Furthermore, in the experimental apparatus involved in the present invention, the structure may be as follows: the moving mechanism includes a ring-shaped or arc-shaped rack (85) with multiple teeth formed on the inner or outer circumferential surface, a pinion (86) having a gear that engages with the teeth of the rack and rotating the rack by a rotation drive unit, and a movable stage (88) mounted on the rack, and the antenna holding part is mounted on the movable stage.

[0026] According to this structure, the test apparatus of the present invention can place the movable antenna mechanism on the periphery of the anechoic chamber, avoiding the attitude-variable mechanism that holds the test object in the center, thereby effectively utilizing the limited internal space of the anechoic chamber.

[0027] Furthermore, the test method of the present invention uses any of the test devices described above, and the test method is characterized by including: a step of selecting one of the plurality of arrival angles or a transmission angle; a step of moving the second test antenna by means of the antenna movable mechanism in such a way as the selected arrival angle or transmission angle; a step of sequentially changing the posture of the test object disposed in the blank area; and a step of measuring the transmission characteristics or reception characteristics of the test object using the first and second test antennas each time the posture of the test object changes.

[0028] As described above, the test apparatus used in the test method of the present invention includes an antenna movable mechanism that allows the position of the second test antenna to be moved at multiple arrival angles or multiple transmission angles relative to the direction of arrival of radio waves from the first test antenna or the direction of transmission of radio waves from the first test antenna. Furthermore, the test method includes a step of moving the second test antenna via the antenna movable mechanism to a selected arrival angle or transmission angle. Therefore, far-field measurements of the transceiver characteristics, such as the RRM characteristics, of the test object can be performed with a smaller number of antennas. By reducing the number of antennas, the cost of antennas and other equipment, as well as installation costs, can be reduced.

[0029] Invention Effects

[0030] According to the present invention, a test apparatus and test method are provided that can perform far-field measurements of the transceiver characteristics such as the RRM characteristics of the test object with a smaller number of antennas. Attached Figure Description

[0031] Figure 1 This is a diagram showing the general structure of the test apparatus according to the first embodiment of the present invention.

[0032] Figure 2 This is a block diagram illustrating the functional structure of the experimental apparatus according to the first embodiment of the present invention.

[0033] Figure 3 This is a block diagram illustrating the functional structure of the integrated control device of the experimental apparatus according to the first embodiment of the present invention.

[0034] Figure 4 This is a block diagram illustrating the functional structure of the NR system simulator of the experimental apparatus according to the first embodiment of the present invention.

[0035] Figure 5 This is a top view taken from above after removing the top plate of the anechoic chamber of the experimental apparatus according to the first embodiment of the present invention.

[0036] Figure 6 This is the front view as seen from the front side after removing the side panel of the radio anechoic chamber.

[0037] Figure 7 This is a schematic diagram showing the configuration of the experimental antenna and reflector inside the anechoic chamber.

[0038] Figure 8 This is a diagram showing the structure and operation of the antenna movable mechanism according to the first embodiment.

[0039] Figure 9 This is a diagram showing a modified example 1 of the antenna holding section.

[0040] Figure 10 This is a schematic diagram showing the configuration of the test antenna and reflector held in the antenna holding part of Modified Example 1.

[0041] Figure 11 This is a diagram showing a modified example 2 of the antenna holding section.

[0042] Figure 12 This is a flowchart illustrating a general method for conducting a test using the test apparatus according to the first embodiment of the present invention.

[0043] Figure 13 This is a diagram showing the structure and operation of the antenna movable mechanism according to the second embodiment.

[0044] Figure 14 This is a diagram showing the schematic structure of the antenna movable mechanism according to the third embodiment.

[0045] Figure 15 This is a diagram showing the schematic structure of the antenna movable mechanism according to the fourth embodiment.

[0046] Figure 16 This is a top view taken from above after the top panel of the radio wave anechoic chamber of the previous experimental setup has been removed. Detailed Implementation

[0047] Hereinafter, the test apparatus and test method according to embodiments of the present invention will be described with reference to the accompanying drawings. Furthermore, the dimensional ratios of the constituent elements in the drawings may not necessarily correspond to the actual dimensional ratios.

[0048] (First Embodiment)

[0049] The test apparatus 1 according to the first embodiment measures the transmission or reception characteristics of a DUT 100 having an antenna 110, for example, measuring the RF characteristics or RRM characteristics of the DUT 100. Therefore, the test apparatus 1 includes an anechoic chamber 50 (also called an OTA chamber), two test antennas 6a and 6b (hereinafter sometimes collectively referred to as test antennas 6), a position variable mechanism 56, an integrated control device 10, an NR system simulator 20, and a signal processing unit 40. The integrated control device 10, the NR system simulator 20, and the signal processing unit 40 constitute the measurement apparatus 2.

[0050] Figure 1 This describes the external structure of test apparatus 1. Figure 2 This represents the functional modules of experimental device 1. Among them, in... Figure 1 The diagram shows the configuration of each component in the state of the radio anechoic chamber 50 as viewed from the front.

[0051] like Figure 1 and Figure 2 As shown, the anechoic chamber 50 has an internal space 51 unaffected by the surrounding radio wave environment. A test antenna 6 is disposed within the internal space 51 of the anechoic chamber 50 and transmits or receives wireless signals with the antenna 110 for measuring the transmission or reception characteristics of the DUT 100. A position-adjustable mechanism 56 changes the position of the DUT 100, which is positioned within the blank area QZ, within the internal space 51 of the anechoic chamber 50. The integrated control unit 10, the NR system simulator 20, and the signal processing unit 40 use one or two test antennas 6 to measure the transmission or reception characteristics of the DUT 100, whose position has been changed by the position-adjustable mechanism 56.

[0052] Test apparatus 1, for example, with Figure 1 The rack structure 90 of the multiple rack housings 90a shown is used together, and is used in such a way that each component is placed in each rack housing 90a. Figure 1 This example illustrates an assembly containing a control unit 10, an NR system simulator 20, and an anechoic chamber 50, respectively housed in three rack housings 90a of the rack structure 90. The components will be described below.

[0053] (Radio Dark Box)

[0054] The anechoic chamber 50 is used to measure the transmitting or receiving characteristics of wireless terminals, for example, to create an OTA (Over-The-Air) test environment for performance testing of 5G wireless terminals. Figure 1 and Figure 2 As shown, the anechoic chamber 50 is, for example, composed of a metal frame body 52 with an internal space 51 in the shape of a cuboid. The anechoic chamber 50 houses the DUT 100 and two test antennas 6 that are directly or indirectly opposite the antenna 110 of the DUT 100 in the internal space 51 to prevent the intrusion of radio waves from the outside and the emission of radio waves to the outside.

[0055] Furthermore, radio wave absorbers 55 are adhered to the entire inner surface of the anechoic chamber 50, namely the bottom surface 52a, side surface 52b, and top surface 52c of the main body 52, thereby ensuring the sound attenuation characteristics of the internal space 51 and enhancing the function of limiting radio wave transmission to the outside. Thus, the anechoic chamber 50 forms an internal space 51 unaffected by the surrounding radio wave environment. The anechoic chamber 50 used in this embodiment is, for example, an anechoic chamber of the CATR (Compact Antenna Test Range) type.

[0056] (DUT)

[0057] The DUT100, set as the test subject, can be a wireless terminal such as a smartphone. Examples of communication standards for the DUT100 include cellular (LTE, LTE-A, W-CDMA, GSM, CDMA2000, 1xEV-DO, TD-SCDMA, etc.), wireless LAN (IEEE 802.11b / g / a / n / ac / ad, etc.), Bluetooth, GNSS (GPS, Galileo, GLONASS, BeiDou, etc.), FM, and digital broadcasting (DVB-H, ISDB-T, etc.). Furthermore, the DUT100 can also be a wireless terminal that transmits and receives wireless signals in the millimeter-wave band corresponding to 5G cellular networks.

[0058] In this embodiment, DUT100 is, for example, a 5G NR wireless terminal. Regarding 5G NR wireless terminals, according to the 5G NR standard, a predetermined frequency band, including other frequency bands used in LTE and others besides the millimeter-wave band, is defined as the communicable frequency range. Therefore, the antenna 110 of DUT100 transmits or receives wireless signals from the predetermined frequency band (5G NR band), which is the object of measurement for the transmission or reception characteristics of DUT100. Antenna 110 is, for example, an array antenna such as a Massive-MIMO antenna, corresponding to the antenna under test in this invention.

[0059] In this embodiment, the DUT100 can transmit and receive test signals and measured signals via the test antenna 6 and, if necessary, via the reflector 7 or the reflector 9 in measurements related to its transmit and receive characteristics within the anechoic chamber 50.

[0060] (Variable posture mechanism)

[0061] Next, the attitude-variable mechanism 56 installed in the internal space 51 of the anechoic chamber 50 will be described. For example... Figure 1 As shown, a posture-variable mechanism 56 is provided on the bottom surface 52a (base plate) of the internal space 51 side in the main body 52 of the radio wave anechoic chamber 50 to change the posture of the DUT 100 arranged in the blank area QZ. The posture-variable mechanism 56 is, for example, a dual-axis positioner with a rotation mechanism that rotates around each of the two axes. The posture-variable mechanism 56 constitutes an OTA test system (Combined-axes system) in which the DUT 100 has rotational freedom around the two axes when the test antenna 6 is set. Specifically, the posture-variable mechanism 56 has a drive unit 56a, a turntable 56b, a support column 56c, and a DUT mounting unit 56d as the test object mounting unit.

[0062] The drive unit 56a is composed of a drive motor such as a stepper motor that generates rotational driving force, and is provided, for example, on the bottom surface 52a. The turntable 56b rotates by a predetermined angle around one of two orthogonal axes by the rotational driving force of the drive unit 56a. The support column 56c is connected to the turntable 56b, extends from the turntable 56b along one axis, and rotates together with the turntable 56b by the rotational driving force of the drive unit 56a. The DUT mounting part 56d extends from the side of the support column 56c along the other axis, and rotates by a predetermined angle around the other axis by the rotational driving force of the drive unit 56a. The DUT 100 is mounted on the DUT mounting part 56d.

[0063] Furthermore, one of the aforementioned axes is, for example, an axis extending vertically relative to the bottom surface 52a (the Y-axis in the figure). And the other axis is, for example, an axis extending horizontally from the side of the support column 56c. This configuration of the posture-variable mechanism 56 allows the DUT 100, held in the DUT mounting portion 56d, to rotate in such a way that, for example, with the center of the DUT 100 as the rotation center, the posture of the antenna 110 relative to the test antenna 6 and the reflector 7 in all three-dimensional directions can be sequentially changed.

[0064] In the OTA test system, the center of the DUT100 or the center of the antenna 110 is positioned at the intersection of the two rotation axes of the attitude-variable mechanism 56, i.e., the rotation center (also called the origin O). The position of the DUT100, which is the origin O of the OTA test system, is the position of the center of the DUT100 or the center of the antenna 110 located inside the anechoic chamber 50. That is, the origin O corresponds to the stationary rotation center when the DUT100 is rotated around the two axes by the attitude-variable mechanism 56.

[0065] (Link antenna)

[0066] Within the anechoic chamber 50, two types of link antennas 5 and 8 are mounted at desired positions on the main body 52 using retainers 57 and 59, respectively, for establishing or maintaining a link (call) with the DUT 100. Link antenna 5 is an LTE link antenna used in non-standalone mode. Link antenna 8, on the other hand, is a 5G link antenna used to maintain a 5G call. Link antennas 5 and 8 are held by retainers 57 and 59 in a directional manner relative to the DUT 100 held in the attitude-variable mechanism 56. Alternatively, instead of using link antennas 5 and 8, experimental antenna 6 can also be used as a link antenna; therefore, the following explanation will focus on the function of experimental antenna 6 as a link antenna.

[0067] (Near field and far field)

[0068] Next, the near field and far field will be explained. The case where the radio wave propagates directly from the antenna to the DUT100 is called the DFF (Direct Far Field) mode, and the case where the radio wave propagates from the antenna to the DUT100 after being reflected by the reflector 7 with a rotating parabolic surface is called the IFF (Indirect Far Field) mode.

[0069] Radio waves radiated by an antenna possess the property of propagating simultaneously from a surface (wavefront) connecting points of phase, extending spherically around the radiator. At distances close to the radiator, the wavefront is a curved sphere (spherical wave), but as distance increases, the wavefront approaches a plane (plane wave). Typically, the region where the wavefront needs to be considered spherical is called the near field, and the region where the wavefront is not considered plane is called the far field. Based on accurate measurements, the DUT100 prefers receiving plane waves over spherical waves.

[0070] To receive plane waves, the DUT100 needs to be positioned in the far field. When the location and size of the antenna 110 within the DUT100 are unknown, the far field becomes the distance from the antenna beyond 2D. 2 The region is / λ. Here, D is the maximum linear dimension of DUT100, and λ is the wavelength of the radio wave. Additionally, when the location and dimensions of antenna 110 within DUT100 are known, D is the antenna dimension.

[0071] In this embodiment, the radio waves from the test antenna 6a are reflected by the rotating parabolic surface of the reflector 7, and the reflected waves are brought to the position of the DUT 100 using a CATR method. According to this method, the distance between the test antenna 6a and the DUT 100 can be shortened, and after reflection on the reflector surface of the reflector 7, the region of the plane wave extends from a straight line, thus reducing propagation loss. The intensity of the plane wave can be expressed by the phase difference of waves in phase. An allowable phase difference for the intensity of the plane wave is, for example, λ / 16. The phase difference can be evaluated, for example, using a vector network analyzer (VNA).

[0072] (Experimental antenna)

[0073] Next, the experimental antenna 6 will be explained.

[0074] Figure 5 This is a top view taken from above after removing the top plate of the anechoic chamber 50 of the test apparatus 1 involved in this embodiment. Figure 6 It involves removing the side panel on the front side of the anechoic chamber 50. Figure 6 (The lower side panel) and the front view as seen from the front side.

[0075] like Figure 5 and Figure 6 As shown, the test antenna 6 includes a reflector-reflecting test antenna 6a as a first test antenna and a mirror-reflecting test antenna 6b as a second test antenna. The reflector-reflecting test antenna 6a transmits or receives wireless signals (hereinafter also referred to as measurement wireless signals) for measuring the transmission or reception characteristics of the DUT 100 between itself and the antenna 110 via a reflector 7. The mirror-reflecting test antenna 6b transmits or receives wireless signals for measuring the transmission or reception characteristics of the DUT 100 between itself and the antenna 110 of the DUT 100 via a reflector 9. Each test antenna 6 includes a horizontally polarized wave antenna and a vertically polarized wave antenna (see reference). Figure 2 ).

[0076] (Reflector-type test antenna)

[0077] First, the antenna 6a for the reflector-type test will be explained.

[0078] The reflector-type test antenna 6a is used together with reflector 7 and functions as a primary radiator. As the test antenna 6a, a directional millimeter-wave antenna, such as a horn antenna, can be used, for example. Reflector 7 has a curved reflective surface, for example made of aluminum, to reflect radio waves used for measurement wireless signals, and has an offset parabolic structure that cuts out a portion of a circular parabolic surface. Figure 1 As shown, the reflector 7 is mounted at the desired position on the side 52b of the anechoic chamber 50 using the reflector holder 58.

[0079] The reflector 7 receives radio waves of the test signal emitted from the test antenna 6a, which acts as a primary radiator, by means of a rotating parabolic surface positioned at a predetermined focal point, and reflects them toward the DUT 100 held in the attitude-variable mechanism 56 (during transmission). Furthermore, the reflector 7 receives radio waves of the measured signal emitted from the antenna 110 by the DUT 100, which has received the aforementioned test signal, and reflects them toward the test antenna 6a (during reception). The reflector 7 is configured in a position and orientation capable of simultaneously performing these transmissions and receptions. That is, the reflector 7 reflects radio waves of wireless signals transmitted and received between the test antenna 6a and the antenna 110 of the DUT 100 by means of a rotating parabolic surface.

[0080] According to this structure, radio waves (e.g., test signals relative to DUT100) emitted from the test antenna 6a can be reflected in a direction parallel to the axis of the rotating parabolic surface by rotating the parabolic surface. Radio waves (e.g., measured signals transmitted from DUT100) incident on the rotating parabolic surface in a direction parallel to its axis are also reflected by the rotating parabolic surface and directed towards the test antenna 6a. In other words, the reflector 7 converts spherical radio waves emitted from the test antenna 6a into plane radio waves and transmits them to DUT100, and converges plane radio waves emitted from DUT100 and incident on the reflector 7 onto the test antenna 6a. Compared to a parabolic surface, the offset parabolic surface not only allows for a smaller reflector 7 itself but also enables a configuration where the mirrors are perpendicularly close, thus miniaturizing the structure of the anechoic chamber 50.

[0081] like Figure 6 As shown, the reflector-type test antenna 6a is positioned below the horizontal plane HP, which is the location of the DUT100 (origin O). The radio wave beam emitted from the test antenna 6a and reflected by the reflector 7 propagates along the negative Z-axis and forms a blank area QZ of the desired radius.

[0082] (Reflector-type experimental antenna)

[0083] Next, the antenna 6b for the reflector-type test will be described.

[0084] The reflector-type test antenna 6b transmits or receives wireless signals between itself and the antenna 110 of the DUT 100 via a planar reflector 9 that reflects the radio waves of the wireless signal used for reflection measurement. The reflector 9 is, for example, made of aluminum and has a flat mirror surface. The radio wave beam emitted from the reflector-type test antenna 6b is mirror-reflected on the reflector 9.

[0085] Figure 7This is a schematic diagram showing the configuration of the reflector 9 and the reflector-reflection test antenna 6b inside the anechoic chamber 50. The reflector 9 and the test antenna 6b, held by the antenna holding unit 600, can rotate and move in the θ direction around the y-axis passing through the origin O via an antenna movable mechanism (not shown). The test antenna 6b is positioned lower than the horizontal plane HP, and the reflector 9 is configured such that the reflection point P5 of the radio wave beam on the reflector surface is located on the horizontal plane HP. The radio wave beam emitted from the test antenna 6b is reflected by the reflector 9 and transmitted to the origin O where the DUT 100 is located. Furthermore, the radio wave beam emitted from the antenna 110 of the DUT 100 is reflected by the reflector 9 and transmitted to the test antenna 6b. If the reflector 9 is not present, the test antenna 6A is configured outside the anechoic chamber 50, thus making it impossible to ensure the antenna distance (distance between O and PA) required for far-field measurements. By bending the propagation path of the radio wave beam through the reflector 9, the test antenna 6b can be positioned inside the anechoic chamber 50, and the required distance between antennas for far-field measurements can be ensured.

[0086] Specifically, in Figure 7 In this model, the distance between O and P5 and the distance between P5 and P15 are added together, which is equal to the distance between antennas required for far-field measurement, i.e., the distance between O and PA. P5 represents the reflection point of the radio beam emitted from the test antenna 6b on the reflector 9, P15 is the center of the opening of the test antenna 6b, and PA is the center of the opening of the hypothetical test antenna 6A. The propagation path between O and P5 lies on the horizontal plane HP. In addition, the radio beam emitted from the reflector-reflecting test antenna 6a is reflected at the reflection point P0 on the reflector 7 and transmitted to the origin O where the DUT100 is located. The propagation path between P0 and O also lies on the horizontal plane HP.

[0087] The reflector-type test antenna 6a forms a so-called indirect far field (IFF), while the mirror-type test antenna 6b forms a direct far field (DFF). An indirect far field refers to the far field formed by a reflector-type antenna that uses a reflector to convert spherical waves into plane waves, while a direct far field refers to the far field directly formed by an antenna that does not use such a reflector. Furthermore, the mirror-type test antenna 6b uses a reflector 9 to reflect the radio wave beam, but the distance the radio wave beam travels from the test antenna 6b to the far field is the same as in the case without a reflector; therefore, it can be considered a DEF-type antenna.

[0088] For example, when the antenna size D of antenna 110 is known, the distance from the reflector-type test antenna 6b through the corresponding reflector 9 to the antenna 110 of DUT100 is greater than 2D. 2 / λ is sufficient. D is the antenna size of antenna 110, and λ is the wavelength of the radio wave transmitted from the reflector-type test antenna 6. This enables far-field measurements of the DUT100.

[0089] The reflector-type test antenna 6b and the reflector 9 are positioned outside the path of the radio beam reflected in the reflector 7 of the reflector-type test antenna 6a and passing through the blank area QZ. According to this structure, the test apparatus 1 of this embodiment can form a good blank area QZ.

[0090] Furthermore, in this embodiment, the blanking area formed by the mirror-reflecting test antenna 6b is assumed to be the same as the blanking area QZ formed by the reflector-reflecting test antenna 6a, but this is not a limitation. The blanking area formed by the mirror-reflecting test antenna 6b may also be different from the blanking area QZ formed by the reflector-reflecting test antenna 6a. For example, if the blanking area QZ formed by the reflector-reflecting test antenna 6a is extended, a wider blanking area can be utilized when measuring RF characteristics, etc., using only the reflector-reflecting test antenna 6a.

[0091] (Arrival Angle)

[0092] like Figure 5 and Figure 6 As shown, the antenna movable mechanism 60 moves the positions of the test antenna 6b and the reflector 9 on each circle, so that the DUT100 can transmit or receive wireless signals at multiple arrival angles with reference to the direction of arrival of the radio wave from the test antenna 6a (negative Z-axis direction). These multiple arrival angles are, for example, 30°, 60°, 90°, 120°, and 150°. This allows for uniform and complete measurement within a specified angle range, thus enabling high-precision far-field measurements of the DUT100's transceiver characteristics, such as RRM characteristics. Therefore, for example, it is possible to measure the RRM characteristics specified in standard 3GPP TR38.810V16.2.0 (2019-03) with high precision.

[0093] Here, "Angle of Arrival (AoA)" refers to the angle formed by the radio beam or the center of the radio beam arriving at the origin O from the test antenna 6, relative to a specific straight line (e.g., the Z-axis) passing through the origin O where the DUT 100 is located. The angle of arrival can be defined by two test antennas. In this case, the angle formed by the radio beam or the center of the radio beam arriving at the origin O from the other test antenna, with the direction of arrival of the radio wave from one test antenna as the reference, is called the "Angle of Arrival" or "Relative Angle of Arrival". Furthermore, when transmitting from the origin O to the test antenna 6 or other test antennas, the direction of transmission is used instead of the direction of arrival, and the angle of departure (AoD) is used instead of the angle of arrival.

[0094] (Antenna movable mechanism)

[0095] Next, the movable antenna mechanism 60 will be described.

[0096] The antenna movable mechanism 60 moves the position of the test antenna 6b in a circle so that it can directly transmit or receive wireless signals at multiple arrival angles to the DUT100, which is positioned in the far field with reference to the direction of arrival of the radio waves from the test antenna 6a. Therefore, the antenna movable mechanism 60 includes an antenna holding part 600 and a moving mechanism 700.

[0097] <Antenna Holding Section>

[0098] The antenna holding section 600 holds the test antenna 6b and the planar reflector 9. The test antenna 6b and the reflector 9 are held in the antenna holding section 600 at a required interval. The reflector 9 reflects the radio waves of the wireless signal transmitted from the test antenna 6b and transmits them to the antenna 110 of the DUT 100, and also reflects the radio waves of the wireless signal transmitted from the antenna 110 of the DUT 100 and transmits them to the test antenna 6b. The antenna movable mechanism 60 moves the position of the planar reflector 9 together with the test antenna 6b.

[0099] According to this structure, the path of the wireless signal transmitted and received between the test antenna 6b and the antenna 110 of the DUT 100 can be changed by the reflector 9, so that even the limited and narrow internal space 51 of the anechoic chamber 50 can ensure the distance between antennas required for far-field measurements.

[0100] like Figure 8 As shown, the antenna holding part 600 has an elongated rod-shaped or columnar support 61 that holds the test antenna 6b and the reflector 9 at intervals along its length. Specifically, a reflector mounting part 62 extending orthogonal to the length direction of the support 61 is provided at one end of the support 61, and the reflector 9 is mounted at the end of the reflector mounting part 62 at a predetermined angle. Furthermore, an antenna mounting part 63 extending orthogonal to the length direction is provided in the middle of the support 61, and an angle adjustment table 64 is mounted at the end of the antenna mounting part 63, and the test antenna 6b is mounted on the angle adjustment table 64 at a predetermined angle. The other end of the support 61 is mounted on the upper surface of a support plate 65, and the support plate 65 is fixed to the movable platform 77 with a slight levitation by a fastener 66. Figure 8 The length direction of the support 61 is vertical.

[0101] The angles of the test antenna 6b and the reflector 9 are set such that the radio wave beam of the wireless signal emitted from the test antenna 6b is reflected by the entire surface of the reflector 9 and transmitted to the DUT100.

[0102] The movable stage 77 is slidably mounted on the arc-shaped guide rail 76 and can move in the direction D2 along a circular track formed with the vertical line passing through the origin O of the DUT100 as the rotation axis (y-axis). Even if the movable stage 77 is located at any position along the length of the guide rail 76, both the movable stage 77 and the antenna holding part 600 mounted on the movable stage 77 are directed toward the direction in which the radio wave beam of the wireless signal emitted from the test antenna 6b is reflected by the reflector 9 and transmitted to the DUT100.

[0103] In this embodiment, a support plate 65 is used, but the end of the support column 61 can also be directly fixed to the movable platform 77.

[0104] <Example 1 of the modification of the antenna holding part>

[0105] Figure 9 This is a diagram showing the structure of a modified example 1 of the antenna holding section. (As shown...) Figure 9 As shown, in Modified Example 1, the support 61 of the antenna holding part 600A is angled relative to the vertical direction. To tilt (reference) Figure 10 ), so that one end of the movable stage 77 mounted on the moving mechanism 700 is more offset from the other end to the side of the central axis (y-axis) of the circular track of the test antenna 6b or reflector 9. Figure 9 (On the left side or the center side of the bottom plate of the anechoic chamber 50). Figure 9 In the middle, the lower end of the support column 61 is directly fixed to the movable platform 77. (And...) Figure 8 Compared to the antenna holding part 600, Figure 9 The area represented by the symbol W is opened, and the space V defined by area W and pillar 61 is opened.

[0106] Thus, in the test apparatus 1 using the antenna holding part 600A of modified example 1, the occupied area and occupied space (volume) of the antenna movable mechanism 60 can be reduced, thereby enabling effective use of the limited internal space 51 of the anechoic chamber 50.

[0107] Figure 10This is a schematic diagram showing the arrangement of the reflector 9 and the reflector-reflecting test antenna 6b inside the anechoic chamber 50 of the test apparatus 1 using the antenna holding unit 600A of Modified Example 1. The reflector 9 and the test antenna 6b, held by the antenna holding unit 600A, can rotate in the θ direction about the y-axis passing through the origin O via an antenna movable mechanism (not shown). The radio wave beam emitted from the test antenna 6b is reflected by the reflector 9 and transmitted to the origin O where the DUT 100 is located. Furthermore, the radio wave beam emitted from the antenna 110 of the DUT 100 is reflected by the reflector 9 and transmitted to the test antenna 6b. If the reflector 9 were not present, the test antenna 6A would be positioned outside the anechoic chamber 50, making it impossible to ensure the antenna distance (O-PA distance) required for far-field measurement. By bending the propagation path of the radio wave beam by the reflector 9, the test antenna 6b can be positioned inside the anechoic chamber 50, and the antenna distance required for far-field measurement can be ensured.

[0108] Specifically, in Figure 10 In this case, the distance between O-P5 and the distance between P5-P15 is equal to the distance between antennas required for far-field measurement, i.e., the distance between O-PA.

[0109] <Modified Example 2 of Antenna Holding Section>

[0110] Figure 11 This is a diagram showing the structure of a modified example 2 of the antenna holding section. (As shown...) Figure 11 As shown, similarly to Modified Example 1, the support 61 of the antenna holding part 600B is angled relative to the vertical direction. The platform is tilted so that one end of the movable stage 77 mounted on the moving mechanism 700 is more offset from the other end towards the side of the central axis (y-axis) of the circular track of the test antenna 6b. Figure 11 (On the left side or the center side of the bottom plate of the anechoic chamber 50). Figure 11 In this configuration, a test antenna 6b is mounted on the upper end of the support column 61 via the antenna mounting part 63. Similar to Modified Example 1, and... Figure 8 Compared to the antenna holding part 600, Figure 11 The area represented by the symbol W is opened, and the space V defined by area W and pillar 61 is opened.

[0111] In the test apparatus 1 using the antenna holding part 600B of Modified Example 2, similarly to Modified Example 1, the occupied area and space (volume) of the antenna movable mechanism 60 can be reduced, thereby enabling efficient use of the limited internal space 51 of the anechoic chamber 50. Modified Example 2 is effective in ensuring the distance between antennas required for far-field measurements even without using a reflector.

[0112] [<Mobile Organization>]

[0113] Return to Figure 8 The moving mechanism 700 includes a linear motion unit 701, a circular motion unit 702, and a link 703 that converts linear motion into circular motion.

[0114] [<Linear Motion Part>]

[0115] The linear motion unit 701 includes a ball screw 70, a nut 71 that is fitted into the ball screw 70 and moves linearly by rotating the ball screw 70, a movable table or movable worktable 72 that is mounted on the upper part of the nut 71 and moves together with the nut 71, a motor 73 that rotates the ball screw 70, and a linear guide rail 74 that guides the linear movement of the movable worktable 72.

[0116] If the ball screw 70 rotates via the motor 73, the nut portion 71 fitted into the ball screw 70 moves in the linear direction D1, thereby causing the movable worktable 72 mounted on the nut portion 71 to move linearly.

[0117] Two pins 75a and 75b are erected at intervals on the upper surface of the movable worktable 72 in a direction orthogonal to the length direction of the ball screw 70.

[0118] <Circular Motion Part>

[0119] The circular motion unit 702 includes an arc-shaped guide rail 76 and a movable stage 77 that spans the guide rail 76 and can move along the guide rail 76. A pin 78 is erected on the upper surface of the movable stage 77.

[0120] <Connecting rod>

[0121] Link 703 converts the linear motion of the movable worktable 72 of the linear motion unit 701 into part of the circular motion of the movable stage 77 of the circular motion unit 702, and connects the movable worktable 72 and the movable stage 77. Specifically, link 703 is an elongated plate with a pin hole 79a formed at one end and an elongated hole 79b formed at the other end. A pin 78, which is mounted on the movable stage 77, passes through the pin hole 79a at one end of link 703, allowing link 703 to rotate around pin 78. Two pins 75a and 75b pass through the elongated hole 79b at the other end of link 703, allowing link 703 to move along the arrangement direction of the two pins 75a and 75b (a direction orthogonal to the direction of linear motion D1). That is, the length direction of link 703 is orthogonal to the direction of movement of the movable worktable 72 of the linear motion unit 701.

[0122] The ball screw 70 is rotated by the drive motor 73, thereby causing the movable worktable 72 mounted on the nut part 71 to move linearly. Accompanying the linear movement of the movable worktable 72, the movable table 77 moves along the guide rail 76. Figure 8The diagram shows the movable stage 77 at position P25 (Figure A) and the movable worktable 72 at position P35 at the right end of the linear motion unit 701. In this configuration, the test antenna 6b can transmit a radio beam, for example, at an arrival angle of 150°, based on the direction of the radio beam arriving at the DUT100 from the test antenna 6a.

[0123] If the movable stage 72 of the linear motion unit 701 is moved to the central position P33, the movable stage 77 of the circular motion unit 702 is driven to position P23 (Figure B). At this time, the test antenna 6b can, for example, transmit a radio beam with an arrival angle of 90°. Similarly, if the movable stage 72 is moved to the left end position P31, the movable stage 77 is driven to position P21 (Figure C). At this time, the test antenna 6b can, for example, transmit a radio beam with an arrival angle of 30°.

[0124] By moving the position of the movable worktable 72, it is possible to form arrival angles of 30°, 60°, 90°, 120°, and 150°.

[0125] According to the above structure, the test apparatus 1 of this embodiment does not need to be equipped with test antennas according to the number of arrival angles for the test, thereby reducing the number of antennas. Furthermore, the test antenna 6b can be moved in a manner that forms any arrival angle within a specified range. Moreover, by avoiding the attitude-variable mechanism 56 that holds the center of the DUT 100 and placing the antenna movable mechanism 60 around the periphery, the occupied area and occupied space (volume) of the antenna movable mechanism 60 are also minimized, thereby making efficient use of the limited internal space 51 of the anechoic chamber 50.

[0126] In this embodiment, the antenna movable mechanism 60 is disposed on the bottom plate of the radio wave anechoic chamber 50, but the placement position is not limited. It can also be disposed on the top plate, and is not limited to horizontal, but can also be disposed vertically or at an angle.

[0127] Next, refer to Figures 2-4 The integrated control device 10, NR system simulator 20, and signal processing unit 40 constituting the test apparatus 1 according to this embodiment will be described.

[0128] (Integrated control device)

[0129] As described below, the integrated control unit 10 centrally controls the NR system simulator 20, the attitude-adjustable mechanism 56, and the antenna movable mechanism 60. Therefore, the integrated control unit 10 is connected to the NR system simulator 20, the attitude-adjustable mechanism 56, and the antenna movable mechanism 60 in a manner that enables them to communicate with each other, for example, via a network 19 such as Ethernet (registered trademark).

[0130] Figure 3This is a block diagram representing the functional structure of the integrated control device 10. For example... Figure 3 As shown, the integrated control device 10 includes a control unit 11, an operation unit 12, and a display unit 13. The control unit 11 is, for example, a computer device. Figure 3 As shown, the computer device includes, for example, a CPU (Central Processing Unit) 11a, a ROM (Read Only Memory) 11b, a RAM (Random Access Memory) 11c, an external interface (I / F) section 11d, a non-volatile storage medium such as an SSD (Solid State Drive) or hard disk drive device (not shown), and various input / output ports.

[0131] CPU 11a performs centralized control of setting the NR system simulator 20 and other objects as objects. ROM 11b stores the OS (Operating System) or other programs used to start CPU 11a, as well as control parameters. RAM 11c stores the OS used by CPU 11a during operation, the execution code of the application program, and data. External interface (I / F) unit 11d has an input interface function for inputting specified signals and an output interface function for outputting specified signals.

[0132] The external I / F unit 11d is connected to the NR system simulator 20 via network 19 in a communicative manner. Furthermore, the external I / F unit 11d is also connected via network 19 to the attitude-adjustable mechanism 56 or the antenna movable mechanism 60 in the anechoic chamber 50. An operation unit 12 and a display unit 13 are connected to the input / output ports. The operation unit 12 is a functional unit for inputting various information such as commands, and the display unit 13 is a functional unit for displaying various information such as input screens or measurement results.

[0133] The aforementioned computer device functions as a control unit 11 by using the CPU 11a to execute programs stored in the ROM 11b, with the RAM 11c as the working area. For example... Figure 3 As shown, the control unit 11 includes a call connection control unit 14, a signal transceiver control unit 15, a DUT posture control unit 17, and an antenna position control unit 18. The call connection control unit 14, the signal transceiver control unit 15, the DUT posture control unit 17, and the antenna position control unit 18 are also implemented by the CPU 11a executing a predetermined program stored in the ROM 11b in the working area of ​​the RAM 11c.

[0134] The call connection control unit 14 controls the establishment of a call (the state of being able to transmit and receive wireless signals) between the NR system simulator 20 and the DUT100 by driving the test antenna 6 to transmit and receive control signals (wireless signals).

[0135] The signal transceiver control unit 15 monitors user operations in the operation unit 12. Taking the start of a prescribed measurement operation involving the user's measurement of the transmission and reception characteristics of the DUT 100 as an opportunity, it sends a signal transmission command to the NR system simulator 20 via the call connection control in the call connection control unit 14. Furthermore, the signal transceiver control unit 15 controls the transmission of test signals to the NR system simulator 20 via the test antenna 6, and controls the transmission of signal reception commands to the NR system simulator 20 and the reception of the measured signal via the test antenna 6.

[0136] Furthermore, the signal transceiver control unit 15 sets the arrival angle during transceiver characteristic tests, such as RRM characteristics, conducted using two test antennas 6. Specifically, it selects one of a plurality of predetermined arrival angles (e.g., 30°, 60°, 90°, 120°, 150°) and sets it as the measurement condition (stored in RAM 11c, etc.). The arrival angle can be selected by the user or automatically by the control unit 11, etc.

[0137] The antenna position control unit 18 controls the position of the test antenna 6b according to the set arrival angle. For example... Figure 5 and Figure 6 As shown, for example, when the set arrival angle is 30°, control is performed by moving the test antenna 6b to position P11 and the reflector 9 to position P1. Therefore, for example, an arrival angle-antenna position correspondence table 18a, which represents the correspondence between the arrival angle and the position of the test antenna 6b, is pre-stored in the ROM 11b. The arrival angle-antenna position correspondence table 18a is expanded and used in the working area of ​​the RAM 11c during control execution. In addition, the setting of the arrival angle or the control of the position of the test antenna 6b can be performed by the control unit 22 of the NR system simulator 20.

[0138] The DUT posture control unit 17 controls and measures the posture of the DUT 100 when it is held in position by the posture variable mechanism 56. To achieve this control, for example, a DUT posture control table 17a is pre-stored in the ROM 11b. The DUT posture control table 17a stores, for example, the number of drive pulses (operation pulses) that determine the rotation drive of the stepper motor as control data when a stepper motor is used as the drive unit 56a.

[0139] The DUT posture control unit 17 drives the posture variable mechanism 56 in such a way that the DUT posture control table 17a is unfolded in the working area of ​​RAM 11c, and according to the DUT posture control table 17a, as described above, the posture of the DUT 100 is changed so that the antenna 110 is sequentially oriented in all three-dimensional directions.

[0140] (NR System Simulator)

[0141] like Figure 4 As shown, the NR system simulator 20 of the experimental apparatus 1 according to this embodiment includes a signal measurement unit 21, a control unit 22, an operation unit 23, and a display unit 24. The signal measurement unit 21 includes a signal generation function unit consisting of a signal generation unit 21a, a digital-to-analog converter (DAC) 21b, a modulation unit 21c, and a transmission unit 21e of an RF unit 21d, and a signal analysis function unit consisting of a receiving unit 21f of the RF unit 21d, an analog-to-digital converter (ADC) 21g, and an analysis and processing unit 21h. Furthermore, two sets of signal measurement units 21 may be provided to accommodate the two experimental antennas 6a and 6b used.

[0142] In the signal generation function section of the signal measurement unit 21, the signal generation unit 21a generates waveform data with a reference waveform. Specifically, for example, it generates an I-component baseband signal and its quadrature component signal, i.e., a Q-component baseband signal. The DAC 21b converts the waveform data (I-component baseband signal and Q-component baseband signal) with the reference waveform output from the signal generation unit 21a from a digital signal into an analog signal and outputs it to the modulation unit 21c. The modulation unit 21c performs modulation processing by mixing the I-component baseband signal and the Q-component baseband signal with a local signal, and then synthesizing the two to output a digital modulated signal. The RF unit 21d generates a test signal corresponding to the frequency of each communication standard from the digital modulated signal output from the modulation unit 21c, and outputs the generated test signal to the signal processing unit 40 through the transmission unit 21e.

[0143] The signal processing unit 40 includes a first signal processing unit 40a that performs signal processing such as frequency conversion for signals transmitted and received between the test antenna 6a and another test antenna 6b, and a second signal processing unit 40b that performs signal processing such as frequency conversion for signals transmitted and received between the test antenna 6a and another test antenna 6b. The first signal processing unit 40a processes the test signals transmitted to the test antenna 6a and outputs them to the test antenna 6a. The second signal processing unit 40b processes the test signals transmitted to the other test antenna 6b and outputs them to the test antenna 6b.

[0144] Furthermore, in the signal analysis function section of the signal measurement unit 21, the RF unit 21d, based on the measured signal transmitted from the DUT100 which has received the aforementioned test signal via the antenna 110 and received by the receiving unit 21f via the signal processing unit 40, converts the measured signal into an intermediate frequency band signal (IF signal) by mixing it with a local signal. The ADC 21g converts the measured signal, which has been converted into an IF signal by the receiving unit 21f via the RF unit 21d, from an analog signal into a digital signal and outputs it to the analysis and processing unit 21h.

[0145] The analysis and processing unit 21h performs the following processing: by digitally processing the digital signal output by ADC21g, i.e. the measured signal, to generate waveform data corresponding to the I-component baseband signal and the Q-component baseband signal respectively, the I-component baseband signal and the Q-component baseband signal are analyzed based on the waveform data.

[0146] In measuring the transmission characteristics (RF characteristics) of the DUT100, the analysis and processing unit 21h can measure, for example, Equivalent Isotropically Radiated Power (EIRP), Total Radiated Power (TRP), spurious radiation, modulation accuracy (EVM), transmit power, constellation diagram, and spectrum. Furthermore, in measuring the reception characteristics (RF characteristics) of the DUT100, the analysis and processing unit 21h can measure, for example, receiver sensitivity, bit error rate (BER), and packet error rate (PER). Here, EIRP is the wireless signal strength in the main beam direction of the DUT100's antenna 110. And TRP is the total power transmitted from the DUT100's antenna 110 into space.

[0147] Regarding the RRM characteristics of DUT100, the analysis and processing unit 21h can also analyze, for example, whether the switching operation from one test antenna to another test antenna is performed normally.

[0148] The control unit 22, like the control unit 11 of the integrated control device 10 described above, is, for example, composed of a computer device including a CPU, RAM, ROM, and various input / output interfaces. The CPU performs prescribed information processing and control for implementing the functions of the signal generation function unit, the signal analysis function unit, the operation unit 23, and the display unit 24.

[0149] The operation unit 23 and the display unit 24 are connected to the input / output interface of the aforementioned computer device. The operation unit 23 is a functional unit for inputting various information such as commands, and the display unit 24 is a functional unit for displaying various information such as input screens and measurement results.

[0150] In this embodiment, the integrated control device 10 and the NR system simulator 20 are separate devices, but they can also be configured as a single device. In this case, the control unit 11 of the integrated control device 10 and the control unit 22 of the NR system simulator 20 can be integrated and implemented using a single computer device.

[0151] (Signal Processing Department)

[0152] Next, the signal processing unit 40 will be described.

[0153] The signal processing unit 40 is disposed between the NR system simulator 20 and the test antenna 6, and includes a first signal processing unit 40a that performs signal processing such as frequency conversion of signals transmitted and received between the test antenna 6a and the test antenna 6b, and a second signal processing unit 40b that performs signal processing such as frequency conversion of signals transmitted and received between the test antenna 6b and the test antenna 6b.

[0154] The first signal processing unit 40a includes an up-conversion converter, a down-conversion converter, an amplifier, and a frequency filter. It performs signal processing such as frequency conversion (up-conversion), amplification, and frequency selection on the test signal transmitted to the test antenna 6a and outputs it to the test antenna 6a. Furthermore, the first signal processing unit 40a performs signal processing such as frequency conversion (down-conversion), amplification, and frequency selection on the measured signal input from the test antenna 6a and outputs it to the signal measurement unit 21.

[0155] The second signal processing unit 40b includes an up-conversion converter, a down-conversion converter, an amplifier, and a frequency filter. It performs signal processing such as frequency conversion (up-conversion), amplification, and frequency selection on the test signal transmitted to the other test antenna 6b, and outputs the signal to the test antenna 6b. Furthermore, the second signal processing unit 40b performs signal processing such as frequency conversion (down-conversion), amplification, and frequency selection on the measured signal input from the other test antenna 6b, and outputs the signal to the signal measurement unit 21.

[0156] (Experimental Methods)

[0157] Next, refer to Figure 12 The flowchart below describes the test method performed using the test apparatus 1 according to this embodiment. Hereinafter, a test (e.g., measurement of transmit / receive characteristics such as RRM characteristics) performed using two test antennas will be described, but this is only one example of the test method, and it is obvious that the specific test method will vary depending on the type of test.

[0158] First, the user places the DUT100 of the test object on the DUT mounting part 56d of the posture variable mechanism 56 located in the internal space 51 of the radio wave anechoic chamber 50 (step S1).

[0159] Next, the user uses the operation unit 12 of the integrated control device 10 to command the control unit 11 to start the measurement start operation of the transmission and reception characteristics of the DUT 100. This measurement start operation can also be performed by the operation unit 23 of the NR system simulator 20.

[0160] The control unit 11 sets one of the preset arrival angles (step S2). For example, when the preset arrival angles are 30°, 60°, 90°, 120°, and 150°, the control unit 11 selects one of the arrival angles (e.g., 30°) and sets it as the arrival angle to be measured (e.g., stored in RAM 11c). The arrival angle can also be set by the user.

[0161] Next, the control unit 11 moves the position of the test antenna 6b to the arrival angle set in step S2. For example, the control is performed as follows: when the set arrival angle is 30°, the test antenna 6b is moved to position P11 and the reflector 9 is moved to position P1; when the arrival angle is 60°, the test antenna 6b is moved to position P12 and the reflector 9 is moved to position P2; when the arrival angle is 90°, the test antenna 6b is moved to position P13 and the reflector 9 is moved to position P3; when the arrival angle is 120°, the test antenna 6b is moved to position P14 and the reflector 9 is moved to position P4; when the arrival angle is 150°, the test antenna 6b is moved to position P15 and the reflector 9 is moved to position P5.

[0162] The call connection control unit 14 of the control unit 11 implements call connection control (step S4) by using the test antenna 6 and transmitting and receiving control signals (wireless signals) with the DUT 100. Specifically, the NR system simulator 20 wirelessly transmits a control signal (call connection request signal) at a predetermined frequency to the DUT 100 via the test antenna 6. On the other hand, the DUT 100, having received the call connection request signal, replies with a control signal (call connection response signal) based on the frequency set for requesting connection. The NR system simulator 20 receives the call connection response signal and confirms that a normal response has been made. This series of processes constitutes call connection control. Through this call connection control, a state is established between the NR system simulator 20 and the DUT 100 where wireless signals at a predetermined frequency can be transmitted and received via the test antenna 6.

[0163] Furthermore, the processing of receiving radio signals from the NR system simulator 20 via the experimental antenna 6 through the DUT100 is called downlink (DL) processing. Conversely, the processing of radio signals transmitted from the NR system simulator 20 via the experimental antenna 6 through the DUT100 is called uplink (UL) processing. The experimental antenna 6 is used to perform link establishment (call) processing and downlink (DL) and uplink (UL) processing after link establishment, and also functions as a link antenna.

[0164] After establishing the call connection in step S4, the DUT posture control unit 17 of the integrated control device 10 controls the posture of the DUT 100 configured in the blank area QZ to a specified posture through the posture variable mechanism 56 (step S5).

[0165] After the DUT100 is controlled to a predetermined posture by the posture variable mechanism 56, the signal transceiver control unit 15 of the integrated control device 10 sends a signal transmission command to the NR system simulator 20. The NR system simulator 20 then transmits a test signal to the DUT100 via the selected test antenna 6 according to the signal transmission command (step S6).

[0166] The experimental signal transmission control based on the NR system simulator 20 is implemented as follows.

[0167] In NR system simulator 20 (reference) Figure 4 In this process, the signal generation unit 21a, under the control of the control unit 22 which has received the aforementioned signal transmission command, generates a signal for generating a test signal. Next, the DAC 21b performs digital-to-analog conversion on the signal generated by the signal generation unit. Then, the modulation unit 21c modulates the analog signal obtained through the digital-to-analog conversion. Next, the RF unit 21d generates a test signal corresponding to the frequency of each communication standard from the modulated signal, and the transmission unit 21e transmits this test signal (DL data) to the signal processing unit 40.

[0168] The signal processing unit 40 is located inside or outside the anechoic chamber 50, and performs signal processing such as frequency conversion (up-conversion), amplification, and frequency selection, and sends the signal to the test antenna 6, which outputs the signal to the DUT 100. Furthermore, to process signals from two test antennas, the signal processing unit 40 can process multiple signals simultaneously.

[0169] In addition, after the signal transceiver control unit 15 starts controlling the transmission of the test signal in step S6, it controls the transmission and reception characteristics of the DUT100 to be measured until the measurement ends, by transmitting the test signal at appropriate intervals.

[0170] On the other hand, the DUT100 receives test signals (DL data) transmitted via the test antenna 6 through the antenna 110 in different posture states that change sequentially according to the posture control performed in step S5, and transmits a response signal, i.e., the measured signal, relative to the test signal.

[0171] After the transmission of the test signal begins in step S6, the receiving process continues under the control of the signal transceiver control unit 15 (step S7). In this receiving process, the test antenna 6 receives the measured signal transmitted from the DUT 100, which has received the aforementioned test signal, and outputs it to the signal processing unit 40. The signal processing unit 40 performs signal processing such as frequency conversion (down-conversion), amplification, and frequency selection, and outputs it to the NR system simulator 20.

[0172] The NR system simulator 20 performs measurement processing of the measured signal, which is frequency-converted by the signal processing unit 40 (step S8).

[0173] Specifically, the receiver 21f of the RF unit 21d of the NR system simulator 20 receives the measured signal that has been processed by the signal processing unit 40. Under the control of the control unit 22, the RF unit 21d converts the measured signal input to the receiver 21f into a lower frequency IF signal.

[0174] Next, under the control of the control unit 22, the ADC 21g converts the IF signal from an analog signal to a digital signal and outputs it to the analysis and processing unit 21h. The analysis and processing unit 21h generates waveform data corresponding to the I-component baseband signal and the Q-component baseband signal, respectively. Furthermore, under the control of the control unit 22, the analysis and processing unit 21h analyzes the measured signal based on the generated waveform data. In addition, in order to perform signal processing for the two test antennas, the signal processing unit 40 can process multiple signals in parallel.

[0175] More specifically, in the NR system simulator 20, the analysis and processing unit 21h, under the control of the control unit 22, measures the transmission and reception characteristics of the DUT100 based on the analysis results of the measured signal.

[0176] For example, the transmission characteristics (RF characteristics) of the DUT100 are assessed as follows: First, under the control of the control unit 22, the NR system simulator 20 transmits an uplink signal transmission request frame as a test signal. In response to this uplink signal transmission request frame, the DUT100 transmits an uplink signal frame as the measured signal to the NR system simulator 20. The analysis and processing unit 21h then performs processing to evaluate the transmission characteristics of the DUT100 based on this uplink signal frame.

[0177] Furthermore, the receiving characteristics (RF characteristics) of the DUT100 are performed, for example, as follows. Under the control of the control unit 22, the analysis and processing unit 21h calculates the ratio of the number of times the measurement frame is transmitted from the NR system simulator 20 as a test signal to the number of times ACK and NACK are received from the DUT100 as a measured signal for the measurement frame as the bit error rate (PER).

[0178] Furthermore, regarding the RRM characteristics of the DUT100, for example, the analysis and processing unit 21h can also change the orientation of the DUT100 under the control of the control unit 22 to test whether the switching operation from one test antenna to another is performed normally.

[0179] In step S8, under the control of the control unit 22, the analysis and processing unit 21h stores the measurement results of the transmission and reception characteristics of the DUT 100 in a storage area such as RAM (not shown). These measurement results may also be displayed on the display unit 24 or the display unit 13.

[0180] Next, the control unit 11 of the integrated control device 10 determines whether the measurement of the transmission and reception characteristics of the DUT 100 has ended for all desired postures (step S9). Here, if it is determined that the measurement has not ended ("No" in step S9), the process returns to step S5 and continues.

[0181] When it is determined that the measurement of all postures has ended ("Yes" in step S9), the control unit 11 determines whether the measurement of all incoming angles has ended (step S10).

[0182] If it is determined that the measurement of all incoming angles has not yet been completed ("No" in step S10), the control unit 11 returns to step S2 and continues processing. If it is determined that the measurement of all incoming angles has been completed ("Yes" in step S10), the control unit 11 ends the test.

[0183] (Functions and Effects)

[0184] As described above, the test apparatus 1 according to this embodiment includes an antenna movable mechanism 60, which moves the position of the test antenna 6b in a circle so that it can directly transmit or receive wireless signals to the DUT 100 located in the far field at multiple arrival angles, based on the direction of arrival of the radio waves from the test antenna 6a. According to this structure, in far-field measurements of the transceiver characteristics such as the RRM characteristics of the DUT 100, it is not necessary to set up test antennas according to the number of arrival angles being tested, thereby reducing the number of antennas. This reduces the cost of equipment such as antennas and installation work.

[0185] Furthermore, the test apparatus 1 according to this embodiment can change the path of the wireless signals transmitted and received between the test antenna 6b and the antenna 110 of the DUT 100 by means of the reflector 9, so that the distance between the antennas required for far-field measurement can be ensured even in the limited and narrow internal space 51 of the radio wave anechoic chamber 50.

[0186] Furthermore, the test apparatus 1 involved in this embodiment is a structure in which the antenna movable mechanism 60 converts the linear motion of the linear motion unit 701 into the circular motion of the circular motion unit 702 through the connecting rod 703. Therefore, the antenna movable mechanism 60 can be set around the periphery of the anechoic chamber 50, avoiding the posture variable mechanism 56 that holds the center of the DUT 100. The area occupied (set) and space occupied (volume) of the antenna movable mechanism 60 are also small, thereby making effective use of the limited internal space 51 of the anechoic chamber 50.

[0187] (Second Implementation)

[0188] Next, the experimental apparatus according to the second embodiment of the present invention will be described.

[0189] The experimental apparatus 1 according to the second embodiment differs from the first embodiment, where the linear motion part 701 and the connecting rod 703 in the antenna movable mechanism 60B are connected at a variable angle at a point where they are fixed at 90°. Other components are the same; identical components are labeled with the same symbols, and detailed descriptions are omitted where appropriate.

[0190] Figure 13 This is a schematic diagram showing the structure and operation of the antenna movable mechanism 60B according to the second embodiment. Figure 13 The antenna holding section 600 is omitted from the illustration. Figure 13 As shown, the connecting rod 703 is connected to the moving worktable 72 in such a way that the angle formed by the length direction of the connecting rod 703 relative to the linear motion direction of the moving worktable 72 of the linear motion unit 701 changes according to the position of the moving worktable 72. Specifically, a pin 75 is erected on the upper surface of the moving worktable 72, and the pin 75 passes through the elongated hole 79b of the connecting rod 703. As a result, the connecting rod 703 can rotate around the pin 75 as a fulcrum, and can move an amount equivalent to the length of the elongated hole 79b along its length direction.

[0191] The movable worktable 72, driven by the motor 73, can move in the linear motion direction D3 along the ball screw 70 and linear guide rail 74 of the linear motion unit 701. A pin 78 is erected on the movable stage 77 where the antenna holding part 600 or 600A is mounted, and the pin 78 passes through the pin hole 79a of the connecting rod 703. Thus, as the movable worktable 72 moves in the linear motion direction D3 via the linear motion unit 701, the movable stage 77 connected by the connecting rod 703 can move in the circular motion direction D4 along the arc-shaped guide rail 76. In other words, the linear motion of the movable worktable 72 driven by the linear motion unit 701 is converted into the circular motion of the movable stage 77 via the connecting rod 703.

[0192] Figure 13 The diagram shows the movable stage 77 at position P25 (Figure A) and the movable worktable 72 at position P45. In this configuration, if an antenna holding part 600 is installed on the movable stage 77, and a test antenna 6b and a reflector 9 are installed on the antenna holding part 600, the test antenna 6b can, for example, transmit a radio beam at an arrival angle of 150°, based on the direction of the radio beam arriving at the DUT100 from the test antenna 6a.

[0193] If the movable stage 72 is moved to the central position P43, the movable stage 77 will follow to position P23 (Figure B). At this time, the test antenna 6b can transmit a radio beam, for example, at an arrival angle of 90°. Similarly, if the movable stage 72 is moved to the left-hand position P41, the movable stage 77 will follow to position P21 (Figure C). At this time, the test antenna 6b can transmit a radio beam, for example, at an arrival angle of 30°.

[0194] According to the above structure, the test apparatus 1 of this embodiment can shorten the length of the linear motion section 701 in the longitudinal direction compared with the first embodiment. As a result, the limited internal space 51 of the radio anechoic chamber 50 can be effectively used by avoiding the posture variable mechanism 56 that holds the DUT 100 in the center within the radio anechoic chamber 50.

[0195] In this embodiment, the antenna movable mechanism 60B is disposed on the bottom plate of the radio wave anechoic chamber 50, but the placement is not limited to this. It can also be disposed on the top plate, and is not limited to horizontal, but can also be disposed vertically or at an angle.

[0196] (Third Implementation)

[0197] Next, the experimental apparatus according to the third embodiment of the present invention will be described.

[0198] The experimental apparatus 1 according to the third embodiment differs from the first and second embodiments in that the point at which the circular motion is achieved using a rack and pinion in the antenna movable mechanism 60C is different from that in the first and second embodiments, which convert linear motion into circular motion. Other components are the same; identical components are labeled with the same symbols, and detailed descriptions are omitted where appropriate.

[0199] Figure 14 This is a schematic diagram showing the structure of the moving mechanism 800 included in the antenna movable mechanism 60C according to the third embodiment. Figure 14 The antenna holding section 600 is omitted from the illustration. Figure 14 As shown, the antenna movable mechanism 60C has an annular rack 81 with multiple teeth 81a formed on its outer peripheral surface and a gear 82a that engages with the teeth 81a of the rack 81. It also includes a pinion 82 that rotates via a motor or other rotary drive unit (not shown) and moves along the rack 81 in a circular direction D5, and a movable stage 84 mounted on the pinion 82. Furthermore, a guide driven wheel 83 is arranged opposite the pinion 82 across the rack 81.

[0200] A variable orientation mechanism 56 for holding the DUT100 is disposed at the center of the annular rack 81. An antenna holding part 600 is mounted on a movable stage 84, and a test antenna 6b and a reflector 9 are mounted on the antenna holding part 600. A rotary drive unit such as a motor causes the pinion 82 to move circularly along the rack 81 and to any position, thereby enabling the test antenna 6b to transmit a radio beam at any angle of arrival, based on the direction of the radio beam arriving at the DUT100 from the test antenna 6a.

[0201] By moving the position of the movable stage 84, for example, it is possible to form arrival angles of 30°, 60°, 90°, 120°, and 150°.

[0202] In this embodiment, the antenna movable mechanism 60C is disposed on the bottom plate of the radio wave anechoic chamber 50, but its placement is not limited to this; it can also be disposed on the top plate, and is not limited to a horizontal position, but can also be disposed vertically or obliquely. Furthermore, teeth 81a are formed on the outer peripheral surface of the rack 81, and a pinion 82 is disposed on the outer side of the rack 81. However, teeth can also be formed on the inner peripheral surface of the rack 81, and the pinion 82 can be disposed on the inner side of the rack 81. In this embodiment, the rack 81 is annular, but it can also be configured as an arc shape covering a range capable of forming the required arrival angle.

[0203] Based on the above structure, the test apparatus 1 according to this embodiment does not require setting up test antennas according to the number of arrival angles for the test in far-field measurements of the RRM characteristics and other transmit / receive characteristics of the DUT100, thereby reducing the number of antennas. This reduces the cost of antennas and other equipment, as well as installation costs. Furthermore, the test apparatus 1 according to this embodiment can place the movable antenna mechanism 60C around the periphery of the anechoic chamber 50, avoiding the attitude-adjustable mechanism 56 holding the DUT100 in the center, thus effectively utilizing the limited internal space 51 of the anechoic chamber 50.

[0204] (Fourth implementation)

[0205] Next, the experimental apparatus according to the fourth embodiment of the present invention will be described.

[0206] The experimental apparatus of the fourth embodiment differs from that of the third embodiment, which moves (rotates) the rack in the antenna movable mechanism 60D at a point where it moves (rotates). Other components are the same; identical components are labeled with the same symbols, and detailed descriptions are omitted where appropriate.

[0207] Figure 15 This is a schematic diagram showing the structure of the moving mechanism 800 of the antenna movable mechanism 60D according to the fourth embodiment. Figure 15 As shown, the antenna movable mechanism 60D has an annular rack 85 with multiple teeth 85a formed on its inner circumferential surface and a gear 86a that engages with the teeth 85a of the rack 85. It also includes a pinion 86 that rotates via a rotary drive unit (not shown) such as a motor, thereby causing the rack 85 to rotate, and a movable stage 88 mounted on the rack 85. Furthermore, a guide portion 87 is provided below the rack 85 to slidably support the rack 85 and guide its rotational movement.

[0208] A variable orientation mechanism 56 for holding the DUT100 is disposed at the center of the annular rack 85. An antenna holding part 600 is mounted on the movable stage 88, and a test antenna 6b and a reflector 9 are mounted on the antenna holding part 600. A pinion 86 is driven to rotate by a rotary drive unit such as a motor, thereby driving the rack 85 to rotate and move the movable stage 88 to any position. As a result, the test antenna 6b can transmit a radio beam at any angle of arrival, based on the direction of the radio beam coming from the test antenna 6a to the DUT100.

[0209] By moving the position of the movable stage 88, for example, it is possible to form arrival angles of 30°, 60°, 90°, 120°, and 150°.

[0210] In this embodiment, the antenna movable mechanism 60D is disposed on the bottom plate of the anechoic chamber 50, but its placement is not limited to this; it can also be disposed on the top plate, and is not limited to a horizontal position, but can also be disposed vertically or obliquely. Furthermore, teeth 85a are formed on the inner circumferential surface of the rack 85, and a pinion 86 is disposed on the inner side of the rack 85. However, teeth can also be formed on the outer circumferential surface of the rack 85, and the pinion 86 can be disposed on the outer side of the rack 85. In this embodiment, the rack 85 is annular, but it can also be configured as an arc shape covering a range capable of forming the required arrival angle.

[0211] Based on the above structure, the test apparatus 1 according to this embodiment does not require setting up test antennas according to the number of arrival angles for the test in far-field measurements of the RRM characteristics and other transmit / receive characteristics of the DUT100, thereby reducing the number of antennas. This reduces the cost of antennas and other equipment, as well as installation costs. Furthermore, the test apparatus 1 according to this embodiment can place the movable antenna mechanism 60D around the periphery of the anechoic chamber 50, avoiding the attitude-adjustable mechanism 56 holding the DUT100 in the center, thus effectively utilizing the limited internal space 51 of the anechoic chamber 50.

[0212] Industrial availability

[0213] As described above, the present invention has the effect of enabling far-field measurements of the transceiver characteristics such as the RRM characteristics of the test object with a smaller number of antennas, and is effective in all test apparatuses and test methods for wireless terminals.

[0214] Symbol Explanation

[0215] 1-Test apparatus, 2-Measuring apparatus, 5, 8-Link antennas, 6, 6a, 6b-Test antennas, 7-Reflector, 9-Reflector, 10-Integrated control unit, 11, 22-Control unit, 11a-CPU, 11b-ROM, 11c-RAM, 11d-External interface unit, 12, 23-Operation unit, 13, 24-Display unit, 14-Call connection control unit, 15-Signal transceiver control unit, 17-DUT posture control unit, 17a-DUT posture control table, 18-Antenna position control unit, 18a- Arrival Angle - Antenna Position Correspondence Table, 19 - Network, 20 - NR System Simulator, 21 - Signal Measurement Unit, 21a - Signal Generation Unit, 21b - DAC, 21c - Modulation Unit, 21d - RF Unit, 21e - Transmitter Unit, 21f - Receiver Unit, 21g - ADC, 21h - Analysis and Processing Unit, 40 - Signal Processing Unit, 40a - First Signal Processing Unit, 40b - Second Signal Processing Unit, 50 - Anechoic Chamber, 51 - Internal Space, 52 - Main Body of the Frame, 52a - Bottom Surface, 52b - Side Surface, 52c - Top Table Surface, 55-Radio wave absorber, 56-Attitude variable mechanism, 56a-Drive unit, 56b-Turntable, 56c-Support column, 56d-DUT mounting part, 57, 59-Holding member, 58-Reflector holding member, 60-Antenna movable mechanism, 600-Antenna holding part, 61-Support column, 62-Reflector mounting part, 63-Antenna mounting part, 64-Angle adjustment table, 65-Support plate, 66-Fixing member, 700, 800-Moving mechanism, 701-Linear motion part, 70-Ball screw, 71-Nut part, 72-Moving part Worktable (moving stage), 73-motor, 74-linear guide rail, 75a, 75b-pin, 702-circular motion part, 76-guide rail, 77-movable stage, 78-pin, 703-connecting rod, 79a-pin hole, 79b-elongated hole, 81, 85-rack, 82, 86-pinion, 83-driven wheel, 84, 88-movable stage, 87-guide part, 90-frame structure, 90a-frame housing, 100-DUT (Device Under Test), 110-antenna (Antenna Under Test), QZ-blank area, HP-horizontal plane.

Claims

1. A test apparatus for measuring the transmission or reception characteristics of a test object (100) having a test antenna (110), said test apparatus (1) comprising: The anechoic chamber (50) has an internal space that is unaffected by the surrounding radio wave environment; The posture-variable mechanism (56) sequentially changes the posture of the test subject arranged in the blank area (QZ) of the internal space; The first test antenna (6a) and the second test antenna (6b) are housed in the internal space and transmit or receive wireless signals with the antenna under test for measuring the transmission or reception characteristics of the object under test. The reflector (7) reflects the wireless signal emitted by the first experimental antenna and converts it into a plane wave wireless signal. and The antenna movable mechanism (60) moves the position of the second test antenna in such a way that it can transmit or receive wireless signals to the test object located in the far field at multiple arrival angles or multiple transmission angles, based on the direction of arrival of the radio waves from the first test antenna or the direction of transmission of the radio waves from the first test antenna.

2. The test apparatus according to claim 1, wherein, The movable antenna mechanism includes an antenna holding part (600) for holding the second test antenna and a moving mechanism (700) for moving the antenna holding part in a circle.

3. The test apparatus according to claim 2, wherein, The antenna holding part has a columnar support (61) for holding the second test antenna, the support being inclined relative to the vertical direction such that one end of the moving mechanism is closer to the central axis of the circle than the other end.

4. The testing apparatus according to claim 2 or 3, further comprising: The reflector (9) reflects the wireless signal transmitted from the second test antenna and sends it to the antenna under test, and also reflects the wireless signal transmitted from the antenna under test and sends it to the second test antenna. The antenna holding section holds the second test antenna and the reflector at intervals along the length direction.

5. The test apparatus according to any one of claims 2 to 4, wherein, The moving mechanism includes a linear motion unit (701) for moving the moving platform (72) in a straight line, an arc-shaped guide rail (76), a movable platform (77) for which the antenna holding part is fixed and can move along the arc-shaped guide rail, and a connecting rod (703) for connecting the moving platform and the movable platform and for moving the movable platform along the arc-shaped guide rail by the linear motion of the moving platform. The link is connected to the moving platform in such a way that the length direction of the link is always orthogonal to the direction of movement of the moving platform.

6. The test apparatus according to any one of claims 2 to 4, wherein, The moving mechanism includes a linear motion unit (701) for moving the moving platform (72) in a straight line, an arc-shaped guide rail (76), a movable platform (77) for which the antenna holding part is fixed and can move along the arc-shaped guide rail, and a connecting rod (703) for connecting the moving platform and the movable platform and for moving the movable platform along the arc-shaped guide rail by the linear motion of the moving platform. The link is connected to the moving platform in such a way that the angle formed by the link's length direction relative to the moving direction of the moving platform changes according to the position of the moving platform.

7. The test apparatus according to any one of claims 2 to 4, wherein, The moving mechanism includes a ring-shaped or arc-shaped rack (81) with multiple teeth formed on its inner or outer circumferential surface, a pinion (82) having a gear that engages with the teeth of the rack and moving along the rack by rotating via a rotary drive unit, and a movable stage (84) mounted on the pinion. The antenna holding part is mounted on the movable platform.

8. The test apparatus according to any one of claims 2 to 4, wherein, The moving mechanism includes a ring-shaped or arc-shaped rack (85) with multiple teeth formed on its inner or outer circumferential surface, a pinion (86) having a gear that engages with the teeth of the rack and rotating the rack by a rotation drive unit, and a movable stage (88) mounted on the rack. The antenna holding part is mounted on the movable platform.

9. A test method using the test apparatus according to any one of claims 1 to 8, the test method comprising: The step of selecting one of the plurality of arrival angles or the emission angle; The step of moving the second test antenna via the antenna movable mechanism in such a way as to become the selected arrival angle or transmission angle; The steps of sequentially changing the posture of the test subject positioned within the blank area; and The step of measuring the transmission or reception characteristics of the test object using the first and second test antennas each time the posture of the test object changes.

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