Measuring antenna and measuring system equipped with it

Abstract

We provide a compact, wideband measuring antenna that ensures sufficient power for transmission and reception to the UE, and a measuring system equipped with it. [Solution] The measuring antenna 10 comprises a ground plate 11, an antenna element 20 having a U-shape, and radio wave absorbers 25, 26 mounted on the antenna element 20. The antenna element 20 has a first conductor plate 21 that is fed at the feed point 12, a second conductor plate 22 positioned at approximately 90 degrees to the first conductor plate 21, and a third conductor plate 23 positioned approximately parallel to the first conductor plate 21 and at approximately 90 degrees to the second conductor plate 22. The radio wave absorbers are mounted on at least the upper surface 23a of the third conductor plate 23 on the side facing the first conductor plate 21. The upper surface 21a of the first conductor plate 21 opposite the lower surface 21b facing the radio wave absorber 25 is positioned close to the antenna of the UE, and the antenna element 20 is spatially coupled to the antenna of the UE.

Description

Technical Field

[0001] The present invention relates to a measurement antenna and a measurement system including the same, and more particularly, to a measurement antenna for a frequency band of a 5G wireless communication system and a measurement system including the same.

Background Art

[0002] A wireless communication terminal (User Equipment: UE) used in a 5G wireless communication system is equipped with a plurality of antennas and uses a communication technology called MIMO (Multiple Input Multiple Output) that simultaneously uses these plurality of antennas. Further, the above UE also uses a technology that increases the maximum transmission capacity by simultaneously transmitting and receiving signals of a plurality of frequencies.

[0003] Functional tests of such UEs have conventionally been performed wired, but in recent years, there has been a demand for so-called OTA (Over The Air) tests in which the UE is housed together with a measurement antenna in a shield box that is not affected by the surrounding radio wave environment, and signals are transmitted and received wirelessly between the UE and the test antenna.

[0004] In order to perform a MIMO test, for example, signals with different amplitudes and phases need to be transmitted and received by each of the plurality of antennas installed in a UE such as a smartphone. For this reason, the measurement antenna needs to be arranged close to the antenna built in the UE. However, when the measurement frequency is low, the size of the measurement antenna becomes large, and it becomes difficult to arrange a plurality of measurement antennas close to the built-in antenna of the UE.

[0005] In 5G wireless communication systems, in addition to the millimeter-wave band, the FR1 (Frequency Range 1) frequency band of 600MHz to 7.125GHz is also used. Since a 600MHz radio wave has a wavelength of 500mm, if a dipole antenna is used, for example, the corresponding antenna length would be 250mm. Therefore, measurement antennas need to be miniaturized to a size that allows multiple antennas to be placed close together on the UE (Unified Environment). At the same time, measurement antennas also need to have a wide bandwidth that can cover the frequency range required for measurement.

[0006] Figure 5 in Non-Patent Document 1 shows a typical method for miniaturizing antenna elements. Furthermore, as described in Non-Patent Document 2, it is empirically known that monopole antennas can be broadened by making the antenna plate-shaped.

[0007] For example, a plate-shaped monopole antenna, as shown in Figure 14, can be considered as a method to achieve miniaturization and broadband. A typical monopole antenna operates by placing a conducting rod with a length of 1 / 4 wavelength on a ground plate. By changing this conducting rod to a conducting plate and bending it into a U-shape as shown in Figure 14, it is possible to make the antenna element 20 about the size of the short side of a smartphone (6cm to 8cm). [Prior art documents] [Non-patent literature]

[0008] [Non-Patent Document 1] Yoshio Koyanagi, "Design Challenges and Solutions for Small Antennas for Mobile Communication Terminals," IEICE Transactions on Electronics, Information and Communication Engineers, Vol. J98-B, No. 9, pp. 842-852 (2015.9) [Non-Patent Document 2] IEICE (Institute of Electronics, Information and Communication Engineers) "Forest of Knowledge" (http: / / www.ieice-hbkb.org / ), Group 4, Part 2, Chapter 4, p. 15 [Overview of the project] [Problems that the invention aims to solve]

[0009] However, the U-shaped antenna element 20 shown in Figure 14 has the following problems. The arrows in Figure 14 indicate the direction of the current flowing through the antenna element 20 at a given moment. Of the three conductor plates 21 to 23 that make up the antenna element 20, only the first conductor plate 21, which is close to the UE, and the third conductor plate 23, which is opposite the first conductor plate 21, function for transmitting and receiving to the UE 200. The influence of the second conductor plate 22, which is perpendicular to the first conductor plate 21 and the third conductor plate 23, on the UE 200 is small.

[0010] Here, since the currents I1 and I3 flowing through the first conductor plate 21 and the third conductor plate 23 are in opposite directions, if the length of the second conductor plate 22 is short relative to the wavelength, it is conceivable that the electromagnetic radiation from currents I1 and I3 will cancel each other out, resulting in a decrease in the amount of power that can be transmitted and received in the direction of the UE.

[0011] The present invention was made to solve these conventional problems, and aims to provide a small, wideband measuring antenna that ensures sufficient power to be transmitted and received to the UE, and a measuring system equipped therewith. [Means for solving the problem]

[0012] To solve the above problems, the measuring antenna according to the present invention comprises a ground plate (11), an antenna element (20) having a U-shape, and radio wave absorbers (25, 26) mounted on the antenna element, wherein the antenna element has a substantially rectangular first conductor plate (21) that is fed at a feed point (12), a substantially rectangular second conductor plate (22) that shares one side in the width direction with the first conductor plate and is arranged at an angle of substantially 90 degrees with respect to the first conductor plate, and the second conductor plate which faces the first conductor plate substantially parallel to it. The radio wave absorber comprises a substantially rectangular third conductor plate (23) that shares one side in the width direction with the plate and is positioned at an angle of approximately 90 degrees to the second conductor plate, wherein the radio wave absorber is mounted on at least the side (23a) of the third conductor plate facing the first conductor plate, and the side (21a) of the first conductor plate opposite to the side (21b) facing the radio wave absorber is positioned in close proximity to the antenna (210) of the object under test (200), so that the antenna of the object under test and the antenna element are spatially coupled.

[0013] For example, the measuring antenna according to the present invention has a configuration in which a plate-shaped monopole antenna is bent, and a radio wave absorber is mounted on the third conductor plate located at the position furthest from the antenna of the object being measured. The measuring antenna according to the present invention configured in this way achieves miniaturization and broad bandwidth, and can secure a sufficient amount of power that can be transmitted to and received from the object being measured.

[0014] Furthermore, the measuring antenna according to the present invention may have a configuration in which the lengths of the first conductor plate and the third conductor plate are 6 cm, and the length of the second conductor plate is 3 cm.

[0015] With this configuration, the measurement antenna according to the present invention can use the 600MHz to 7.125GHz frequency band of FR1 as its operating frequency band.

[0016] Furthermore, the measurement system according to the present invention is a measurement system (100) that uses a plurality of the above-described measurement antennas, and is configured to perform MIMO communication between each of the antenna elements of each measurement antenna and the plurality of antennas of the object to be measured.

[0017] With this configuration, the measurement system according to the present invention can perform MIMO communication in a state close to the antenna of the object to be measured by using a plurality of small measurement antennas.

[0018] Further, the measurement system according to the present invention may be configured to include a shield box (50) that houses the plurality of measurement antennas and the object to be measured inside and blocks the intrusion of electromagnetic waves from the outside.

[0019] Further, the measurement system according to the present invention further includes an antenna installation part (63) for installing the plurality of measurement antennas and an object-to-be-measured installation part (64) that is installed on top of the plurality of measurement antennas and for installing the object to be measured, and both are further housed in the shield box, and grid lines are printed on the upper surface (63a) of the antenna installation part and the upper surface (64a) of the object-to-be-measured installation part, respectively.

[0020] With this configuration, since grid lines are printed on the upper surface of the antenna installation part and the upper surface of the object-to-be-measured installation part, respectively, the measurement system according to the present invention can easily install the measurement antenna and the object to be measured at desired installation positions.

Advantages of the Invention

[0021] The present invention provides a small and wideband measurement antenna that can sufficiently secure the amount of power that can be transmitted and received by a UE, and a measurement system including the same.

Brief Description of the Drawings

[0022] [Figure 1] It is a side view showing an example of the basic configuration of a measurement antenna according to a first embodiment of the present invention. [Figure 2] It is a perspective view showing the external structure of the measurement antenna. [Figure 3] It is a cross-sectional view of the measurement antenna. [Figure 4]It is a block diagram showing the configuration of a measurement system according to a second embodiment of the present invention. [Figure 5] It is a diagram showing the external structure of a shield box included in a measurement system according to a second embodiment of the present invention, where (a) is a perspective view seen from the front side, and (b) is a perspective view seen from the back side. [Figure 6] It is a perspective cross-sectional view showing the structure of the shield box. [Figure 7] It is a view when looking down from above at the state where a lower partition plate is provided in the shield box. [Figure 8] It is a view when looking down from above at the state where an antenna tray is provided in the shield box. [Figure 9] It is a view when looking down from above at the state where a plurality of measurement antennas are installed on the antenna tray. [Figure 10] It is a view when looking down from above at the state where a UE tray is installed on a plurality of measurement antennas. [Figure 11] It is a view when looking down from above at the state where a UE is installed on the UE tray. [Figure 12] (a) is a diagram schematically showing a situation where the positions of the UE and the measurement antenna are greatly deviated, and (b) is a diagram schematically showing a situation where a dummy antenna is installed between the antenna tray of the UE and the UE tray. [Figure 13] It is a flowchart showing the processing of a measurement method using a measurement system according to a second embodiment of the present invention. [Figure 14] It is a side view showing an example of the basic configuration of a conventional plate-shaped monopole antenna.

Embodiments for Carrying Out the Invention

[0023] Hereinafter, embodiments of a measurement antenna according to the present invention and a measurement system including the same will be described with reference to the drawings. Note that the dimensional ratios of the respective components on each drawing do not necessarily match the actual dimensional ratios.

[0024] (First Embodiment) Figure 1 is a side view showing an example of the basic configuration of a measuring antenna 10 according to the first embodiment of the present invention.

[0025] The measuring antenna 10 comprises a ground plate 11 which is a flat conductor, an antenna element 20 with a U-shape that is fed from a feed point 12, and radio wave absorbers 25 and 26 mounted on the antenna element 20. The ground plate 11, the feed point 12, and the antenna element 20 constitute a monopole antenna.

[0026] The antenna element 20 includes a first conductor plate 21, a second conductor plate 22, and a third conductor plate 23. The first conductor plate 21, the second conductor plate 22, and the third conductor plate 23 are formed, for example, by bending a single metal plate into a U-shape.

[0027] The first conductor plate 21 is a roughly rectangular flat conductor and is powered by a coaxial cable at the power supply point 12. One side in the width direction (y direction) of the first conductor plate 21 and the second conductor plate 22 are shared, and the second conductor plate 22 is positioned at an angle of approximately 90 degrees to the first conductor plate 21.

[0028] The second conductor plate 22 is a roughly rectangular flat conductor, and as described above, it shares one side in the width direction with the first conductor plate 21 and is positioned at an angle of approximately 90 degrees to the first conductor plate 21. The second conductor plate 22 is parallel to and opposite the ground plate 11.

[0029] The third conductor plate 23 is a roughly rectangular flat conductor, sharing one of the two sides in the width direction of the second conductor plate 22 that is not shared with the first conductor plate 21, and is positioned at an angle of approximately 90 degrees to the second conductor plate 22. The third conductor plate 23 is parallel to and opposite the first conductor plate 21.

[0030] If the operating frequency band of the measurement antenna 10 is to be, for example, FR1's 600MHz to 7.125GHz, then a metal plate with a width of 2cm, a length of 15cm, and a thickness of 0.5mm should be bent so that the x-direction length of the first conductor plate 21 is 6cm, the z-direction length of the second conductor plate 22 is 3cm, and the x-direction length of the third conductor plate 23 is 6cm.

[0031] The radio wave absorber 25 is mounted on the upper surface 23a of the third conductor plate 23 on the side facing the first conductor plate 21. The radio wave absorber 25 attenuates the radiation waves caused by the current I3 flowing through the third conductor plate 23 and suppresses interference with the radiation waves caused by the current I1 flowing through the first conductor plate 21.

[0032] However, in order to avoid attenuation of the radiated waves caused by the current I1 flowing through the first conductor plate 21, it is desirable to provide a gap between the lower surface 21b of the first conductor plate 21 and the upper surface 25a of the radio wave absorber 25.

[0033] Furthermore, by loading a radio wave absorber 26 onto the lower surface 23b of the third conductor plate 23 opposite to the upper surface 23a facing the first conductor plate 21, the radiated waves from the current I3 flowing through the third conductor plate 23 can be attenuated even more effectively. Alternatively, the entire perimeter of the third conductor plate 23 may be covered with a radio wave absorber.

[0034] Here, the upper surface 21a of the first conductor plate 21, opposite to the lower surface 21b facing the radio wave absorber 25, is positioned in close proximity to the antenna 210 of the UE200, which is the object under test. This spatially couples the antenna 210 of the UE200 with the antenna element 20.

[0035] Figures 2 and 3 show more detailed configuration examples of the measuring antenna 10. Figure 2 is a perspective view showing the external structure of the measuring antenna 10. Figure 3 is a cross-sectional view of the measuring antenna 10.

[0036] As shown in Figures 2 and 3, the measuring antenna 10 has a configuration in which the ground plate 11, feed point 12, antenna element 20, and radio wave absorbers 25 and 26 are housed in a dielectric antenna housing 30.

[0037] The metal plates constituting the first conductor plate 21, the second conductor plate 22, and the third conductor plate 23 are made of, for example, copper, aluminum, brass, or gold.

[0038] The ground plate 11 is provided with a hole for inserting an SMA (Sub Miniature Type A) coaxial connector 13. The SMA coaxial connector 13 has a central conductor 14, a dielectric 15 surrounding the central conductor 14, and an outer conductor 16 surrounding the dielectric 15.

[0039] The dielectric 15 of the SMA coaxial connector 13 is inserted into a hole provided in the ground plate 11, and the tip of the central conductor 14 is soldered to the first conductor plate 21. The point where the first conductor plate 21 and the central conductor 14 are electrically connected by soldering constitutes the power supply point 12. The outer conductor 16 is electrically connected to the ground plate 11.

[0040] A coaxial cable (not shown) is connected to the SMA coaxial connector 13, and power is supplied to the power supply point 12 of the first conductor plate 21 from a measuring device (described later) via this coaxial cable.

[0041] The radio wave absorbers 25 and 26 are attached to the antenna element 20 and the antenna housing 30 surrounding the antenna element 20 using double-sided tape or the like. The radio wave absorber 25 is installed so as to cover the entire upper surface 23a of the third conductor plate 23. The radio wave absorber 26 is installed in the space between the bottom surface of the antenna housing 30 and the lower surface 23b of the third conductor plate 23 so as to cover the entire lower surface 23b of the third conductor plate 23.

[0042] Spacers 27 and 28, made of a low dielectric constant material such as polystyrene foam, are inserted into the gap between the upper surface 21a of the first conductor plate 21 and the lower surface 31b of the upper wall 31 of the antenna housing 30, and into the gap between the lower surface 21b of the first conductor plate 21 and the upper surface 25a of the radio wave absorber 25. These spacers 27 and 28 suppress vibrations of the antenna element 20 in response to external vibrations, and prevent load from being placed on the soldered joint between the central conductor 14 of the SMA coaxial connector 13 and the first conductor plate 21.

[0043] As described above, the measurement antenna 10 according to this embodiment has a configuration in which a plate-shaped monopole antenna is bent, and a radio wave absorber 25 is mounted on the third conductor plate 23, which is located at the position furthest from the antenna 210 of the UE200. The measurement antenna 10 according to this embodiment, configured in this way, achieves miniaturization and broad bandwidth, and can secure a sufficient amount of power that can be transmitted and received to the UE200.

[0044] Furthermore, in the measurement antenna 10 according to this embodiment, if the lengths of the first conductor plate 21 and the third conductor plate 23 are 6 cm and the length of the second conductor plate 22 is 3 cm, the frequency band of FR1 from 600 MHz to 7.125 GHz can be used.

[0045] (Second embodiment) Next, a measurement system according to a second embodiment of the present invention will be described with reference to the drawings. Components similar to those in the first embodiment will be denoted by the same reference numerals, and their descriptions will be omitted as appropriate. Similarly, operations similar to those in the first embodiment will also be omitted as appropriate.

[0046] Figure 4 is a block diagram showing the configuration of the measurement system 100 of this embodiment, which uses multiple measurement antennas 10 of the first embodiment.

[0047] As shown in Figure 4, the measurement system 100 of this embodiment inputs a test signal to a UE200 having multiple antennas 210, analyzes the signal to be measured output from the UE200, and performs various tests such as protocol tests and throughput tests. For example, the measurement system 100 includes a measuring device 40, a display device 48, an operating device 49, and a shielded box 50.

[0048] The UE200 is a wireless terminal such as a smartphone that can send and receive wireless signals in the FR1 frequency band, and is a UE capable of communication using at least the MIMO method.

[0049] In Figure 4, the shielded box 50 houses, for example, a UE200 having four antennas 210 and for example, four measuring antennas 10, inside the box (internal space) in a state where electromagnetic waves from the outside are blocked (shielded) from entering the internal space, and provides an OTA test environment through the spatial coupling of each antenna 210 of the UE200 and each measuring antenna 10.

[0050] As shown in Figure 4, the measuring device 40 includes a signal transmission unit 41, a signal reception unit 42, an analysis processing unit 43, an input / output interface (I / F) unit 44, and a test control unit 45.

[0051] The signal transmission unit 41 outputs a test signal to the UE200, which is housed in the shielded box 50, via the measurement antenna 10 and the antenna 210 of the UE200.

[0052] The signal receiving unit 42 receives the signal to be measured, which is output from the UE200 to which the test signal has been input, via the antenna 210 and measurement antenna 10 of the UE200.

[0053] The analysis processing unit 43 performs analysis processing on the signal under test received by the signal receiving unit 42, corresponding to various tests such as protocol tests and throughput tests.

[0054] The above test signal includes control signals for performing various controls in accordance with the UE200's communication standards, such as putting the UE200 into a call connection state with the measurement system 100 of this embodiment. The above-mentioned signal under measurement is the response signal from the UE200 to the test signal output from the measurement system 100 of this embodiment, or a transmission signal output from the UE200 independently of the said test signal.

[0055] The input / output interface (I / F) section 44 is a wideband directional coupler that passes the output frequency of the test signal output from the signal transmission section 41, and is composed of, for example, a Wilkinson-type splitter. The input / output interface (I / F) section 44 is connected to a connector section 56 (see Figure 5) provided in the shielded box 50 by a coaxial cable 46.

[0056] Furthermore, the connector section 56 is connected to the measurement antenna 10 installed inside the shielded box 50 via the coaxial cable 57. In other words, the input / output I / F section 44 can input the test signal output from the signal transmission section 41 to the measurement antenna 10 via the coaxial cable 46, the connector section 56, and the coaxial cable 57, and can also input the signal to be measured from the UE200, which has received the test signal at the antenna 210, to the signal receiving section 42.

[0057] The test control unit 45 is composed of a control device such as a computer that includes, for example, a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), an FPGA (Field Programmable Gate Array), a ROM (Read Only Memory), RAM, and an HDD (Hard Disk Drive), and controls the operation of each of the above-mentioned parts that make up the measuring device 40.

[0058] The test control unit 45 controls the signal transmission unit 41 and the signal reception unit 42 to perform 4x4 MIMO communication between each antenna element 20 of the four measurement antennas 10 and the four antennas 210 of the UE200.

[0059] The operating device 49 is for receiving user input and consists of a user interface such as an operating knob, various keys, switches, buttons, and soft keys on the display screen of the display device 48. The operating device 49 also performs various settings related to various tests such as protocol tests and throughput tests, and sets various measurement conditions on the settings screen.

[0060] The display device 48 is composed of, for example, a display device such as an LCD (Liquid Crystal Display) or a CRT (Cathode Ray Tube), and displays setting screens, measurement result screens, etc., based on display control signals from the test control unit 45. The display device 48 may also have operating functions for the operating device 49, such as soft keys on the display screen.

[0061] Next, the configuration of the shield box 50 will be described. Figures 5(a) and 5(b) show the external structure of the shield box 50 in this embodiment, where Figure 5(a) is a perspective view from the front and Figure 5(b) is a perspective view from the rear.

[0062] As shown in Figures 5(a) and (b), the shield box 50 has a rectangular parallelepiped shape with one side open and an internal space, and a lid portion 53 that is supported by the casing body portion 51 via a hinge portion 52 and can open and close. A fastener 54 is provided on the outer surface of the casing body portion 51 to prevent the closed lid portion 53 from opening. The casing body portion 51 and the lid portion 53 are made of a conductive metal such as iron, stainless steel, aluminum, copper, brass, or alloys thereof.

[0063] Figures 6 to 11 show the internal structure of the shield box 50. Figures 7 to 11 show the internal structure of the shield box 50 with the lid 53 removed.

[0064] As shown in Figures 6 and 7, the shield box 50 has radio wave absorbers 55 attached to its inner surface, that is, the bottom surface 51a and side wall surface 51b of the housing body 51, and the inner surface (not shown) of the lid 53. The radio wave absorbers 55 absorb electromagnetic waves generated by the antenna 210 or measuring antenna 10 of the UE200 when the lid 53 is closed, preventing them from leaking to the outside.

[0065] Furthermore, as shown in Figures 6 and 7, the shield box 50 has multiple support columns 60 and UE tray mounting members 61 provided on the bottom surface 51a of the housing body 51. The shield box 50 also has a lower partition plate 62 through which the support columns 60 pass and which is positioned horizontally to the bottom surface 51a of the housing body 51.

[0066] The support columns 60 are made of cylindrical resin members and are arranged in multiples on the bottom surface 51a of the housing body 51 at predetermined intervals both vertically and horizontally, and are erected vertically relative to the bottom surface 51a. The lower partition plate 62 is positioned to cover the bottom surface 51a of the housing body 51.

[0067] As shown in Figures 6 and 8, an antenna tray 63 for mounting multiple measuring antennas 10 is installed above the lower partition plate 62. The antenna tray 63 is fixed so that its lower surface 63b is inserted into the tip of the support column 60 and its upper surface 63a is horizontal to the bottom surface 51a of the housing body 51. The antenna tray 63 constitutes the antenna mounting section of the present invention.

[0068] The antenna tray 63 is made of foamed material such as polystyrene foam to prevent electromagnetic waves radiated from the UE200's antenna 210 and measurement antenna 10 from being reflected inside the shielding box 50 during OTA testing of the UE200.

[0069] Furthermore, the upper surface 63a of the antenna tray 63 is printed with grid lines that serve as a guide for the placement of the measuring antenna 10. These grid lines allow the measuring antenna 10 to be easily placed in the desired position, making it easy to reproduce tests under the same conditions.

[0070] As shown in Figures 6 and 9, multiple measuring antennas 10 are installed on the upper surface 63a of the antenna tray 63.

[0071] As shown in Figures 9 to 11, the UE tray 64 is for installing the UE200 in a horizontal position and is installed so as to be in contact with the upper surface 61a of the UE tray installation member 61 and the upper surface 31a of each measuring antenna 10 placed on the antenna tray 63. The UE tray 64 is made of a transparent material with radio wave transparency, such as acrylic, so that the position of the measuring antenna 10 can be seen when the user installs the UE200. The UE tray 64 constitutes the part for installing the object to be measured in this invention.

[0072] The UE tray mounting member 61 is made of a cylindrical resin member. Five UE tray mounting members 61 are provided in the internal space of the housing body 51 along the surface of the radio wave absorber 55. A notch 61b is formed at the upper end of the UE tray mounting member 61 to receive the UE tray 64, keeping the horizontal movement of the UE tray 64 restricted.

[0073] As shown in Figure 11, the UE200 is placed on the top surface 64a of the UE tray 64. The top surface 64a of the UE tray 64 has the same grid pattern as the antenna tray 63 printed on it, taking into consideration the reproducibility of the UE200's placement.

[0074] Inside the shield box 50, the distance from the upper surface 21a of the first conductor plate 21 of the measuring antenna 10 to the lower surface of the UE200 (i.e., the distance to the upper surface 64a of the UE tray 64) is, for example, 9 mm when the thickness of the spacer 27 is 3 mm, the thickness of the upper wall 31 of the antenna housing 30 is 3 mm, and the thickness of the UE tray 64 is 3 mm.

[0075] Ideally, the upper surface 61a of the UE tray mounting member 61 and the upper surface 31a of the measuring antenna 10 are all at the same height. However, in reality, due to manufacturing tolerances, the upper surface 31a of the measuring antenna 10 is often slightly higher than the upper surface 61a of the UE tray mounting member 61. In such cases, the UE tray 64 does not come into contact with the upper surface 61a of the UE tray mounting member 61, and the notch 61b simply acts as a positioning element for the UE tray 64.

[0076] As shown in Figure 12(a), if the positions of the UE200 and the measurement antenna 10 are significantly misaligned horizontally, the UE tray 64 may become distorted depending on the weight of the UE200. In such cases where the weight of the UE200 cannot be supported by the UE tray 64, a dummy antenna 220 can be installed between the antenna tray 63 directly below the UE200 and the UE tray 64, as shown in Figures 6 and 12(b).

[0077] The dummy antenna 220 is made of foam material such as polystyrene foam and is the same height as the measuring antenna 10, thus preventing the UE tray 64 from being distorted by the weight of the UE200.

[0078] Next, an example of a measurement method using the measurement system 100 according to this embodiment will be explained with reference to the flowchart in Figure 13.

[0079] First, as shown in Figure 8, the antenna tray 63 is attached to the support pole 60 (step S1).

[0080] Next, as shown in Figure 9, four measuring antennas 10 are placed on the upper surface 63a of the antenna tray 63 (step S2). At this time, although not shown in Figure 9, the SMA coaxial connector 13 of each measuring antenna 10 is connected to the connector part 56 with a coaxial cable 57, and the connector part 56 is connected to the input / output I / F part 44 of the measuring device 40 with a coaxial cable 46.

[0081] Next, as shown in Figure 10, the UE tray 64 is placed on the upper surface 31a of the four measuring antennas 10 (step S3). At this time, if necessary, a dummy antenna 220 is inserted between the antenna tray 63 and the UE tray 64.

[0082] Next, as shown in Figure 11, the UE200 is placed on the upper surface 64a of the UE tray 64 (step S4).

[0083] Next, the lid 53 is closed over the main housing 51 and secured with the fastener 54 (step S5). As a result, the UE200 and the multiple measuring antennas 10 are sealed in the shielded box 50 in a way that blocks the intrusion of electromagnetic waves from the outside into the internal space of the main housing 51, and the UE200 is ready for testing.

[0084] After the test preparations are complete, in response to a predetermined test start operation by the user, the signal transmission unit 41 of the measuring device 40 outputs a test signal to the UE200 via the measuring antenna 10 and the antenna 210 of the UE200 (signal transmission step S6).

[0085] Next, the signal receiving unit 42 of the measuring device 40 receives the signal to be measured output from the UE200, which has the test signal input to it, via the antenna 210 and measuring antenna 10 of the UE200 (signal reception step S7).

[0086] Next, the analysis processing unit 43 of the measuring device 40 performs analysis processing on the signal to be measured received in the signal reception step S7, in accordance with the UE200 communication standard (analysis processing step S8).

[0087] As described above, the measurement system 100 according to this embodiment can perform MIMO communication in close proximity to the antenna 210 of the UE200 by using multiple small measurement antennas 10.

[0088] Furthermore, in the measurement system 100 according to this embodiment, grid lines are printed on the upper surface 63a of the antenna tray 63 and the upper surface 64a of the UE tray 64, respectively, making it possible to easily install the measurement antenna 10 and UE 200 at the desired installation positions. [Explanation of Symbols]

[0089] 10 Measuring Antennas 11 Groundboard 12 Power supply point 13 SMA coaxial connectors 14. Central conductor 15 Dielectrics 16 Outer conductor 20 Antenna elements 21 First Conductor Plate 21a Top side 21b Bottom side 22 Second Conductor Plate 23 Third Conductor Plate 23a Top side 25,26 Radio wave absorber 27, 28 Spacers 30 Antenna housing 40 Measuring device 50 Shield Boxes 60 pillars 61 UE tray mounting component 61a Top side 61b Notch 63 Antenna Tray 63a top surface 64 UE trays 64a top surface 100 Measurement Systems 200 UE 210 Antenna

Claims

1. It comprises a ground plate (11), an antenna element (20) having a U-shape, and radio wave absorbers (25, 26) mounted on the antenna element, The aforementioned antenna cable is A roughly rectangular first conductor plate (21) is supplied with power at the power supply point (12), A substantially rectangular second conductor plate (22) shares one side in the width direction with the first conductor plate and is positioned at an angle of approximately 90 degrees to the first conductor plate, The device includes a substantially rectangular third conductor plate (23) which is positioned substantially parallel to the first conductor plate, shares one side in the width direction with the second conductor plate, and is positioned at an angle of approximately 90 degrees to the second conductor plate. The radio wave absorber is mounted on at least the side (23a) of the third conductor plate facing the first conductor plate. A measuring antenna characterized in that the surface (21a) of the first conductor plate opposite to the surface (21b) facing the radio wave absorber is positioned in close proximity to the antenna (210) of the object to be measured (200), and the antenna of the object to be measured and the antenna element are spatially coupled.

2. The measuring antenna according to claim 1, characterized in that the lengths of the first conductor plate and the third conductor plate are 6 cm, and the length of the second conductor plate is 3 cm.

3. A measurement system (100) using a plurality of measuring antennas as described in claim 1 or claim 2, A measurement system characterized by performing MIMO communication between each of the antenna elements of each of the measurement antennas and the plurality of antennas of the object to be measured.

4. The measurement system according to claim 3, characterized in that it comprises a plurality of measuring antennas and a shield box (50) that houses the object to be measured and blocks the intrusion of electromagnetic waves from the outside.

5. An antenna mounting section (63) for installing multiple measuring antennas, A portion of the object to be measured (64), which is installed on top of the multiple measuring antennas and is used to place the object to be measured, is further housed within the shield box. The measurement system according to claim 4, characterized in that grid lines are printed on the upper surface (63a) of the antenna mounting section and the upper surface (64a) of the object to be measured mounting section, respectively.

Images