JP6606158B2 - Wireless terminal measuring apparatus and wireless terminal measuring method - Google Patents

Description

  The present invention relates to a wireless terminal measuring apparatus and a wireless terminal measuring method using a circularly polarized antenna.

  In recent years, with the progress of multimedia, wireless terminals (smartphones or the like) on which an antenna for wireless communication such as cellular and wireless LAN is mounted are actively produced. In the future, in particular, wireless terminals that transmit and receive wireless signals compatible with IEEE802.11ad, 5G cellular, and the like that use broadband signals in the millimeter wave band are required.

  In wireless terminal manufacturing factories, output levels and reception sensitivities of transmission radio waves determined for each communication standard are measured for wireless communication antennas equipped with wireless terminals, and it is determined whether predetermined standards are met. A performance test is performed.

  Conventionally, when performing the above performance test, each wireless terminal as a device under test (DUT) is placed in an electromagnetic shielding box, and the control terminal and antenna terminal of the DUT are connected to the coaxial cable. The work of connecting to a measuring instrument was performed. In the present situation where tens of thousands of DUTs can be inspected per day, the inspection time per unit is very limited, and efficient measurement in a short time is required.

  However, it is possible to shorten the measurement time by the measuring instrument by increasing the speed and parallelization of the CPU built in the measuring instrument. However, with respect to the connection time of the DUT and the measuring instrument using the coaxial cable, the coaxial cable is used by the user. Therefore, it is difficult to reduce the time significantly.

  When the DUT antenna radiates radio signals in the K and Ka band bands (18 GHz to 40 GHz), the DUT antenna terminal and measuring device are connected by a coaxial cable. There is a problem in that a loss is large when transmitted through a coaxial cable, and accurate measurement cannot be performed.

  Therefore, a measuring instrument has been proposed that performs a DUT performance test by transmitting and receiving radio signals to and from the DUT, and eliminates the need for a coaxial cable connection between the DUT and the measuring instrument. Such a measuring instrument includes, for example, a circularly polarized antenna as an antenna for transmitting and receiving radio signals with a DUT antenna (see, for example, Patent Document 1).

International Publication 2006/051947

  In recent years, in wireless terminals such as smartphones, a MIMO (Multi Input Multi Output) method has been widely adopted as a technique for improving transmission speed (throughput). The MIMO scheme is a scheme in which high-speed data communication is performed using M × N paths formed between a plurality (M) of antennas on the transmission side and a plurality (N) of antennas on the reception side.

  In a measuring instrument that uses a plurality of circularly polarized antennas as disclosed in Patent Document 1 and simultaneously transmits radio signals to a plurality of MIMO antennas built in a DUT, a plurality of antennas in a radio terminal Depending on the arrangement, the wireless terminal needs to be sandwiched between a pair of circularly polarized antennas.

  However, in the configuration as described above, a part of the radio signal may not be obtained depending on the polarization rotation direction unless measures such as installing an object that blocks a signal such as a shielding material is installed between the pair of circularly polarized antennas. The mutual antennas will receive, and the measurement accuracy of various measurement items such as modulation accuracy (EVM) and adjacent channel leakage power will be significantly deteriorated.

  The present invention has been made to solve such a conventional problem, and without installing an object that blocks a signal such as a shield material between circularly polarized antennas facing each other with the object to be tested interposed therebetween. An object of the present invention is to provide a wireless terminal measuring apparatus and a wireless terminal measuring method capable of maintaining the isolation performance between the circularly polarized antennas facing each other.

In order to solve the above-described problems, a wireless terminal measurement apparatus according to the present invention is provided for an object under test having a plurality of antennas including an antenna installed on one side and another antenna installed on the other side. A wireless terminal measuring apparatus for performing measurement, wherein the first circular bias is spatially coupled to the antenna that is disposed at a position facing one surface of the object to be tested and is disposed on one surface side of the object to be tested. A wave antenna and a second circularly polarized antenna that is disposed at a position facing the other surface of the test object and is spatially coupled to the antenna installed on the other surface side of the test object. A plurality of circularly polarized antennas, a plurality of circularly polarized antennas, a signal transmitting unit that outputs a plurality of test signals simultaneously to the object under test via the plurality of antennas, and the plurality of test signals are input. Whether the test target A signal receiving unit that receives a plurality of measured signals to be output via the plurality of antennas and the plurality of circularly polarized antennas, and an analysis process for the plurality of measured signals received by the signal receiving unit The circularly polarized antenna includes a dielectric substrate, a ground plane conductor that is superposed on one surface side of the dielectric substrate, and one surface or the other surface of the object to be tested. A circularly polarized antenna element formed on the opposite surface of the dielectric substrate and having a predetermined polarization rotation direction, and one end side of each is connected to the ground plane conductor, and the dielectric substrate is arranged along the thickness direction thereof. A plurality of metal posts constituting a cavity by extending the other end side to the opposite surface of the dielectric substrate so as to surround the antenna element, and the dielectric substrate of A frame-like conductor that is short-circuited along the direction in which the other end sides of the plurality of metal posts are arranged on the facing side and provided with a rim having a predetermined width in the antenna element direction, and The cavity and the frame-shaped conductor constitute a resonator, the structural parameters of the resonator and the antenna element are adjusted, and the resonance frequency of the resonator is set to a desired value. Including at least one of an inner dimension Lw of the cavity, the rim width L _R of the frame-shaped conductor, the number of turns of the antenna element, a basic length a0 of the antenna element, and an element width W of the antenna element, and the frame shape the rim width L _R of the conductor, said a width of approximately 1/4 of the wavelength of a surface wave propagating along the dielectric surface of the substrate, one side or other of the object to be tested, wherein the plurality of antennas is installed Surface normals and before each The normal line of the opposite surface of the dielectric substrate of the circularly polarized antenna intersects, and the rotation direction of the predetermined polarization is different between the first circularly polarized antenna and the second circularly polarized antenna. .

  With this configuration, the wireless terminal measurement apparatus according to the present invention is configured so that an object that blocks a signal such as a shielding material is not installed between the circularly polarized antennas facing each other with the object to be tested interposed therebetween. The isolation performance can be maintained.

  Also, with this configuration, the radio terminal measuring apparatus according to the present invention can reduce multiple reflections of the signal under measurement between the antenna under test and the circularly polarized antenna. That is, the wireless terminal measurement apparatus according to the present invention suppresses an amplitude error caused by multiple reflections occurring between the antenna under test and the circularly polarized antenna, and accurately performs measurement on the object under test. Can do.

  Also, with this configuration, in the wireless terminal measurement apparatus according to the present invention, the circularly polarized antenna can suppress the generation of surface waves, and the radiation characteristics of the antenna can be set to desired characteristics.

  Further, in the wireless terminal measuring apparatus according to the present invention, the normal line of the radiation surface of each antenna and the normal line of one surface or the other surface of the test object on which the plurality of antennas are installed are parallel, The radiation direction of the antenna may be a normal direction of the radiation surface of each antenna.

  With this configuration, the wireless terminal measurement apparatus according to the present invention can reduce multiple reflection of test signals between the antenna under test and the circularly polarized antenna.

  Further, in the wireless terminal measuring apparatus according to the present invention, the normal of the opposite surface of the dielectric substrate of each circularly polarized antenna and the normal of the radiation surface of each circularly polarized antenna are parallel, The radiation direction of the circularly polarized antenna may be a normal direction of the radiation surface of each circularly polarized antenna.

  With this configuration, the wireless terminal measurement apparatus according to the present invention can reduce multiple reflections of the signal under test and the test signal between the antenna under test and the circularly polarized antenna.

  Further, in the wireless terminal measuring apparatus according to the present invention, the antenna element is formed in a square spiral type or a circular spiral type having a spiral center side end, and is formed in the square spiral type or the circular spiral type. The antenna element may further include a power supply pin that is connected to one end of the spiral on the center side of the antenna element and that penetrates the dielectric substrate and the ground plane conductor.

  In addition, the wireless terminal measuring apparatus according to the present invention includes a circularly polarized antenna having a conveyance unit that conveys the object under test in a conveyance path, and an inlet and an outlet for conveying the object under test. And a determination unit that determines whether or not the entire object to be tested is conveyed to a predetermined area in the measurement box, and the signal transmission unit is configured to perform the determination by the determination unit. On the condition that it is determined that the entire object under test is conveyed to the predetermined area, the object under test conveyed by the conveying unit is simultaneously passed through the plurality of circularly polarized antennas and the plurality of antennas. The plurality of test signals are output, and the signal receiving unit receives the plurality of test signals on the condition that the determination unit determines that the entire object to be tested is conveyed to the predetermined area. Force has been said it may be a configuration in which the plurality of the measured signal which is output from the test object is received via the plurality of antennas and the plurality of the circularly polarized antenna.

  With this configuration, the wireless terminal measurement apparatus according to the present invention automatically determines that the entire object under test is transported to a predetermined area in the measurement box and starts a performance test for the object under test. Performance tests can be performed on various wireless terminals, and the test time can be greatly shortened.

  The wireless terminal measurement apparatus according to the present invention is provided above the transport path and prevents electromagnetic waves generated by the plurality of antennas or the plurality of circularly polarized antennas from leaking from the entrance and the exit. The electromagnetic wave absorption part may be further provided, and the measurement box may have an electromagnetic wave shielding function.

  A radio terminal measurement method according to the present invention is a radio terminal measurement method using any one of the radio terminal measurement devices described above, wherein the test object is provided via the plurality of circularly polarized antennas and the plurality of antennas. Simultaneously transmitting the plurality of test signals to the plurality of signals to be measured output from the test target to which the plurality of test signals are input, the plurality of antennas and the plurality of circularly polarized waves A signal receiving step for receiving via an antenna; and an analysis processing step for performing analysis processing on the plurality of signals under measurement received in the signal receiving step.

  With this configuration, the wireless terminal measurement method according to the present invention enables the inter-polarized antennas to be opposed to each other without installing an object that blocks a signal such as a shielding material between the circularly-polarized antennas opposed to each other with the object to be tested interposed therebetween. Thus, it is possible to accurately measure the object to be tested while maintaining the isolation performance.

  Further, a wireless terminal measurement method according to the present invention is a wireless terminal measurement method using any one of the above wireless terminal measurement devices, a transport step of transporting the object to be tested in the transport path, and the device under test A determination step for determining whether or not the entire object is transported to a predetermined area in the measurement box; and the determination step determines that the entire target object is transported to the predetermined area. As a condition, a signal transmission step of simultaneously outputting the plurality of test signals to the object to be tested conveyed by the conveyance unit via the plurality of circularly polarized antennas and the plurality of antennas, and the step to be tested by the determination step The plurality of test signals are output from the input target under test on the condition that it is determined that the entire target is transported to the predetermined area. A signal receiving step for receiving a plurality of signals under measurement via the plurality of antennas and the plurality of circularly polarized antennas, and analyzing the plurality of signals under measurement received in the signal receiving step An analysis processing step.

  With this configuration, the wireless terminal measurement method according to the present invention automatically determines that the entire object under test is transported to a predetermined area in the measurement box and starts a performance test for the object under test. Performance tests can be performed on various wireless terminals, and the test time can be greatly shortened.

  The present invention is a radio that can maintain isolation performance between opposing circularly polarized antennas without installing an object that blocks a signal such as a shield material between the opposing circularly polarized antennas across the object to be tested. A terminal measurement apparatus and a wireless terminal measurement method are provided.

It is a block diagram which shows the structure of the radio | wireless terminal measuring apparatus which concerns on the 1st Embodiment of this invention. It is a perspective view which shows a mode that DUT is hold | maintained at the terminal holder with which the wireless terminal measuring device which concerns on the 1st Embodiment of this invention is provided. (A) is the sectional view on the AA line of FIG. 2, (b) is the sectional view on the BB line of FIG. It is a perspective view which shows the structure of the circularly polarized antenna with which the radio | wireless terminal measuring apparatus which concerns on the 1st Embodiment of this invention is provided. (A) is a front view which shows the structure of LHCP of the circularly polarized antenna in the 1st Embodiment of this invention, (b) is the structure of RHCP of the circularly polarized antenna in the 1st Embodiment of this invention. It is a front view. It is a rear view which shows the structure of the circularly polarized wave antenna in the 1st Embodiment of this invention. (A) is 4A-4A expanded sectional view of Fig.5 (a), (b) is the 4B-4B line expanded sectional view in the modification of Fig.5 (a). FIG. 5 is an enlarged sectional view taken along line 5-5 in FIG. (A) is an enlarged front view showing a configuration of a main part of the circularly polarized antenna according to the first embodiment of the present invention, and (b) is an essential part of the circularly polarized antenna according to the first embodiment of the present invention. It is an enlarged front view which shows the structure of the modification of a part. It is an enlarged front view which shows the structure of the other modification of the principal part of the circularly polarized wave antenna in the 1st Embodiment of this invention. It is a characteristic view when the structure of the principal part of the circularly polarized wave antenna in the 1st Embodiment of this invention is remove | excluded. It is a characteristic view when using the structure of the principal part of the circularly polarized wave antenna in the 1st Embodiment of this invention. It is a schematic diagram which shows an example of the positional relationship of the circularly polarized antenna and DUT antenna in the 1st Embodiment of this invention. (A) is a schematic diagram showing a configuration for measuring a first circular polarization antenna in the embodiment of the S ₁₁ and S ₂₁ of the present invention, (b) is a circle in the first embodiment of the present invention it is a schematic view showing another arrangement for measuring S ₁₁ and S ₂₁ of the polarization antenna. It is a graph showing the S ₁₁ of the circularly polarized antenna according to the first embodiment of the present invention measured in the configuration of FIG. 14 (a). Is a graph showing the circularly polarized antenna of S ₂₁ in the first embodiment of the present invention measured in the configuration of FIG. 14 (a). It is a graph showing the S ₁₁ of the circularly polarized antenna according to the first embodiment of the present invention measured in the configuration of FIG. 14 (b). Is a graph showing the circularly polarized antenna of S ₂₁ in the first embodiment of the present invention measured in the configuration of FIG. 14 (b). (A) is a graph showing S ₂₁ when the distance between two circularly polarized antennas in the first embodiment of the present invention is 1 cm and the inclination angle is 0 °, and (b) is the graph of the present invention. 1cm distance between the two circularly polarized antenna in one embodiment, is a graph showing the S ₂₁ in the case where the inclination angle and 5 °. (A) is a graph showing S ₂₁ when the distance between two circularly polarized antennas in the first embodiment of the present invention is 1.5 cm and the tilt angle is 0 °, and (b) is the present invention. the first embodiment 1.5cm distance between two circularly polarized antenna in the form of a graph showing the S ₂₁ when the inclination angle was set to 5 °. The two circularly polarized antennas having the same main polarization rotation direction and the two circular polarization antennas having different main polarization rotation directions in the first embodiment of the present invention are provided between the two circular polarization antennas. 2cm distance is a graph showing the S ₂₁ in the case where the inclination angle and 5 °. In the measurement system including two circularly polarized antennas having the same main polarization rotation direction and two circular polarization antennas having different main polarization rotation directions in the first embodiment of the present invention, It is a table | surface which shows the value of residual EVM when the distance between circularly polarized antennas is 2 cm, and an inclination angle is 5 degrees. It is a flowchart for demonstrating the process of the radio | wireless terminal measurement method by the radio | wireless terminal measurement apparatus which concerns on the 1st Embodiment of this invention. It is a block diagram which shows the structure of the radio | wireless terminal measuring apparatus which concerns on the 2nd Embodiment of this invention. It is sectional drawing along the conveyance direction of the belt conveyor with which the radio | wireless terminal measuring apparatus which concerns on the 2nd Embodiment of this invention is equipped, and an electromagnetic wave shield box. It is a perspective view which shows the structural example of the electromagnetic wave absorption part of the electromagnetic wave shield box in the 2nd Embodiment of this invention. It is a perspective view which shows the other structural example of the electromagnetic wave absorption part of the electromagnetic wave shield box in the 2nd Embodiment of this invention. It is a perspective view which shows the structural example in the case of using a metal plate as an electromagnetic wave absorption part of the electromagnetic wave shield box in the 2nd Embodiment of this invention. It is a perspective view which shows the other structural example in the case of using a metal plate as an electromagnetic wave absorption part of the electromagnetic wave shield box in the 2nd Embodiment of this invention. It is a flowchart for demonstrating the process of the radio | wireless terminal measurement method by the radio | wireless terminal measurement apparatus which concerns on the 2nd Embodiment of this invention. It is sectional drawing for demonstrating the radio | wireless terminal measurement method by the radio | wireless terminal measurement apparatus which concerns on the 2nd Embodiment of this invention.

  Hereinafter, embodiments of a wireless terminal measuring apparatus and a wireless terminal measuring method according to the present invention will be described with reference to the drawings.

(First embodiment)
As shown in FIG. 1, the wireless terminal measurement apparatus 1 according to the first embodiment of the present invention inputs a plurality of test signals to a DUT 100 having a plurality of antennas 110 and outputs a plurality of signals to be measured output from the DUT 100. Is used to measure transmission / reception characteristics. For example, the wireless terminal measurement device 1 includes a terminal holder 50, a measurement unit 51, a display unit 52, and an operation unit 53.

  The DUT 100 is a wireless terminal such as a smartphone. Communication standards for DUT 100 include cellular (LTE, LTE-A, W-CDMA (registered trademark), GSM (registered trademark), CDMA2000, 1xEV-DO, TD-SCDMA, etc.), wireless LAN (IEEE802.11b / g / a / n / ac / ad, etc.), Bluetooth (registered trademark), GNSS (GPS, Galileo, GLONASS, BeiDou, etc.), FM, and digital broadcasting (DVB-H, ISDB-T, etc.).

  The antenna 110 radiates radio waves of linear polarization such as vertical polarization and horizontal polarization. Further, the antenna 110 may be configured to be able to switch the polarization direction of linearly polarized waves in terms of time.

  As shown in FIGS. 2A and 2B, the terminal holder 50 is made of, for example, a dielectric material having a rectangular outer shape, and a slot portion 54 into which the DUT 100 can be inserted and removed, and a plurality of circularly polarized waves. An antenna 20 is provided inside. Furthermore, the terminal holder 50 may have a door 55 for opening and closing the opening of the slot portion 54. As shown in FIG. 2C, the DUT 100 is housed and held in the terminal holder 50, thereby including an antenna installed on one side of the DUT 100 and another antenna installed on the other side. The positional relationship between the plurality of antennas 110 and the plurality of circularly polarized antennas 20 is fixed.

  3A and 3B are a cross-sectional view taken along line AA and a cross-sectional view taken along line BB in FIG. 2C, respectively. As shown in these drawings, the terminal holder 50 has a holding portion 56 for holding the circularly polarized antenna 20 at a predetermined angle with respect to the radiation surface of the antenna 110 of the DUT 100. A radio wave absorber for preventing electromagnetic waves generated by the antenna 110 of the DUT 100 or the circularly polarized antenna 20 from leaking out of the terminal holder 50 is attached to the inner wall surface 50 a of the terminal holder 50. It is desirable that

  Alternatively, the terminal holder 50 may be configured as a fastener to which a plurality of circularly polarized antennas 20 are attached. In this case, the positional relationship between the plurality of antennas 110 of the DUT 100 and the plurality of circularly polarized antennas 20 is fixed by sandwiching the DUT 100 with the terminal holder 50.

  As shown in FIG. 1, the measurement unit 51 includes a signal transmission unit 61, a signal reception unit 62, an analysis processing unit 63, a switching unit 64, a storage unit 65, and a test control unit 66. Measurements relating to the output level of radio waves to be transmitted, reception sensitivity, and the like are performed on the DUT 100.

  The signal transmission unit 61 outputs a plurality of test signals to the DUT 100 held by the terminal holder 50 simultaneously via the plurality of circularly polarized antennas 20 and the plurality of antennas 110 of the DUT 100.

  The signal receiving unit 62 receives a plurality of signals under measurement output from the DUT 100 to which a plurality of test signals are input via the plurality of antennas 110 and the plurality of circularly polarized antennas 20 of the DUT 100. .

  The analysis processing unit 63 performs an analysis process corresponding to the communication standard of the DUT 100 on the plurality of signals under measurement received by the signal receiving unit 62. Specific examples of analysis processing performed by the analysis processing unit 63 include modulation accuracy (EVM), transmission power level, transmission spectrum mask, error vector amplitude, adjacent channel leakage power, and measurement of spurious radiation.

  Furthermore, the analysis processing unit 63 can execute minimum input sensitivity, maximum input level, adjacent channel removal, non-adjacent channel removal, and the like as analysis processing related to the MIMO reception test.

  Note that the test signal includes a control signal for performing various controls corresponding to the communication standard of the DUT 100, such as setting the DUT 100 in a call connection state with respect to the wireless terminal measuring apparatus 1 of the present embodiment. Further, the signal under measurement is a response signal from the DUT 100 to the test signal output from the wireless terminal measurement apparatus 1 of the present embodiment, or a transmission signal output from the DUT 100 regardless of the test signal.

  The switching unit 64 is a wideband directional coupler that passes the output frequency of the test signal output from the signal transmission unit 61, and is configured by, for example, a Wilkinson distributor. The switching unit 64 is connected to the circularly polarized antenna 20 via a coaxial cable, and inputs the test signal output from the signal transmitting unit 61 to the circularly polarized antenna 20 and receives the DUT 100 received by the circularly polarized antenna 20. It is possible to input a signal under measurement from the signal receiving unit 62.

  The test control unit 66 is composed of, for example, a microcomputer including a CPU, a ROM, a RAM, and an HDD that constitute the storage unit 65, a personal computer, and the like, and controls operations of the above-described units constituting the measurement unit 51.

  The signal transmission unit 61, the signal reception unit 62, and the analysis processing unit 63 may be configured by digital circuits such as an FPGA (Field Programmable Gate Array) and an ASIC (Application Specific Integrated Circuit), or may be stored in the storage unit 65 in advance. The predetermined program thus executed is executed by the test control unit 66 so that it can be configured as software. Alternatively, the signal transmission unit 61, the signal reception unit 62, and the analysis processing unit 63 can be configured by appropriately combining hardware processing by a digital circuit and software processing by a predetermined program. Note that the test control unit 66 can also add or update the storage unit 65 by receiving a new program or a program whose version has been changed from the outside.

  The display unit 52 is constituted by a display device such as an LCD or CRT, for example, and based on a control signal from the test control unit 66, a soft key, a pull-down menu, a text for displaying a measurement result, setting measurement conditions, and the like. The operation target such as a box is displayed.

  The operation unit 53 is for performing an operation input by a user, and is configured by a touch panel provided on the surface of the display screen of the display unit 52, for example. Alternatively, the operation unit 53 may include an input device such as a keyboard or a mouse. The operation unit 53 may be configured by an external control device that performs remote control using a remote command or the like. An input operation by the operation unit 53 is detected by the test control unit 66. Using the operation unit 53, the user can select a communication standard supported by the DUT 100 from a plurality of communication standards.

  Hereinafter, the configuration of the circularly polarized antenna 20 will be described. 4 to 8 show the basic structure of the circularly polarized antenna 20.

  That is, FIG. 4 is a perspective view shown for explaining the configuration of the circularly polarized antenna 20. FIGS. 5A and 5B are front views for explaining the configuration of the circularly polarized antenna 20. FIG. 6 is a rear view for explaining the configuration of the circularly polarized antenna 20. FIG. 7A is an enlarged sectional view taken along line 4A-4A in FIG. Moreover, FIG.7 (b) is the 4B-4B expanded sectional view in the modification of Fig.5 (a). FIG. 8 is an enlarged sectional view taken along line 5-5 of FIG.

  As shown in FIGS. 4 to 8, the circularly polarized antenna 20 according to the present embodiment basically includes a dielectric substrate 21, a ground plane conductor 22 superposed on the one surface 21 a side of the dielectric substrate 21, and a dielectric A circularly polarized antenna element 23 formed on the opposite surface 21b of the body substrate 21 and having a predetermined polarization rotation direction.

  Further, a feeding portion 26 for feeding an excitation signal to the antenna element 23 is formed on the opposite side of the dielectric substrate 21 across the ground plane conductor 22. The power supply unit 26 includes a power supply dielectric substrate 27 and a microstrip line power supply line 28 formed on the surface of the power supply dielectric substrate 27 opposite to the ground plane conductor 22 and having the ground plane conductor 22 as ground. .

  As the dielectric substrate 21 and the feeding dielectric substrate 27, materials such as RO4003 (Rogers) having a low loss in the quasi-millimeter wave band can be used.

As the material of the dielectric substrate 21 and the dielectric substrate 27 for power feeding, any material having a low loss and a dielectric constant of about 2 to 5 can be used. For example, a glass cloth Teflon substrate or various thermosetting resin substrates can be used. Be a candidate. For example, in the configuration shown in FIG. 7A, the dielectric constants of the dielectric substrate 21 and the power feeding dielectric substrate 27 are both 3.62 and the height h ₁ of the dielectric substrate 21 is 1.1 mm. the height _{h 2} of the dielectric substrate 27 may be, eg, 0.3 mm.

  The antenna element 23 is formed on the opposite surface 21b side of the dielectric substrate 21 by, for example, a right-handed rectangular spiral (see FIG. 5A) or a left-handed rectangular spiral (see FIG. 5B) formed by a pattern printing technique. It is an unbalanced antenna.

  The circularly polarized antenna 20 has one end connected to the side end (feeding point) on the spiral center side of the antenna element 23, penetrates the dielectric substrate 21 in the thickness direction, and passes through the hole 22a of the ground plane conductor 22. It has a feed pin 25 that passes non-conductingly and penetrates the power supply dielectric substrate 27 that constitutes the power supply unit 26 and projects the other end on the surface.

  The power supply unit 26 is not limited to the above-described configuration of the microstrip line, and the power supply pin 25 may be an unbalanced power supply line such as a coaxial cable, a coplanar line having a ground plane conductor 22 as a ground, or a microstrip line. Any configuration may be used as long as power is supplied from the other end side. When the circularly polarized antenna 20 having the configuration shown in FIG. 5A is fed from the feed pin 25, the rotation direction of the main polarization from the antenna element 23 is counterclockwise circularly polarized (left hand circular polarization): LHCP) radio waves can be emitted. On the other hand, the circularly polarized antenna 20 having the configuration shown in FIG. 5 (b) is fed from the feed pin 25, so that the rotation direction of the main polarization from the antenna element 23 is a clockwise circular polarization (right hand circular). Polarization (RHCP) radio waves can be emitted. In FIG. 6 and subsequent drawings, only the configuration in which the main polarization is LHCP is shown unless otherwise specified.

  However, in a circularly polarized antenna having only such a structure, surface waves along the surface of the dielectric substrate 21 are excited, so that desired characteristics cannot be obtained as a circularly polarized antenna due to the influence of the surface waves.

  In view of this, in the circularly polarized antenna 20 of this embodiment, as a structure for suppressing the excitation of the surface wave along the surface of the dielectric substrate 21, in addition to the above structure, FIG. 7A and FIG. As shown, a cavity structure composed of a plurality of metal posts 30 is employed.

  Specifically, for example, a plurality of columnar metal posts 30 are connected at one end side to the ground plane conductor 22, penetrate the dielectric substrate 21 along the thickness direction, and each other end side is a dielectric. A cavity is formed by extending to the opposite surface 21 b of the substrate 21 and being provided at predetermined intervals so as to surround the antenna element 23.

  Furthermore, in addition to the cavity structure, the circularly polarized antenna 20 of the present embodiment sequentially shorts the other end sides of the plurality of metal posts 30 along the arrangement direction to the opposite surface 21b side of the dielectric substrate 21. In addition, a frame-like conductor 32 provided to extend from the connection position with each metal post 30 in the direction of the antenna element 23 by a predetermined distance is provided.

  In the circularly polarized antenna 20 of the present embodiment, surface waves can be suppressed by the synergistic effect of the cavity structure and the frame-shaped conductor 32. That is, the circularly polarized antenna 20 according to the present embodiment includes the cavity structure and the frame-shaped conductor 32, thereby significantly reducing radio wave leakage from the antenna side surface as compared with a conventional general planar antenna. Can be suppressed.

  As shown in FIG. 7B, the plurality of metal posts 30 are formed with a plurality of holes 301 penetrating the dielectric substrate 21 and plated on the inner walls of the plurality of holes 301 (through-hole plating). Accordingly, it can be realized as a plurality of hollow metal posts 30 '.

  In this case, the lower end portions of the plurality of hollow metal posts 30 ′ by through-hole plating are connected to the ground plane conductor 22 via lands 302 formed by pattern printing technology on the one surface 21 a side of the dielectric substrate 21. Has been made.

  Hereinafter, in order to explain the effect of surface wave suppression by the cavity structure and the frame-shaped conductor 32, the simulation results on the structural parameters of each part and the characteristics of the circularly polarized antenna 20 obtained by changing the structural parameters Will be described.

  First, elements that can be structural parameters of each part will be described.

  The frequency of use of this circularly polarized antenna 20 is 18 to 40 GHz in the K and Ka band bands, and the square spiral of the antenna element 23 has a basic length of a0, and a line having a length of a0 and an arbitrary multiple thereof is 90 degrees. It arranges for every angle.

  A typical example of such a square spiral is shown in FIG. That is, in this example, the element width W is set to 0.25 mm, the basic length a0 is set to 0.45 mm, and the line lengths of 2a0, 2a0, 3a0, 3a0, 4a0, and 4a0 are set every 90 degrees, and the final line length is set. Is a square spiral of nine turns (nine-turn spiral) as a whole.

  Further, the rectangular spiral shown in FIG. 9B is a case where the basic length a0 ′ is longer than the basic length a0 in FIG. 9A and the number of turns is reduced.

  In this example, the element width W is set to 0.25 mm, the basic length a0 ′ is set to 0.7 mm, and the line lengths of 2a0 ′, 2a0 ′, 3a0 ′, 3a0 ′, and 4a0 ′ are set every 90 degrees. The length of the line is about 1.5a0 ′, and a total of 8 turns (turn-spiral) square spiral.

  In this case, the final line length is selected to be about 1.5a0 ′ so as to optimize the axial ratio and reflection characteristics of circularly polarized waves.

  In the following description and embodiment, an example of a square spiral is shown as the antenna element 23 to be employed in the circularly polarized antenna 20.

  However, as shown in FIG. 10, as the antenna element 23 to be employed in the circularly polarized antenna 20, a circular spiral antenna element 23 may be used instead of the square spiral.

  The circular spiral antenna element 23 shown in FIG. 10 has, for example, a radius initial value SR = 0.2 mm from a reference point, an element width W = 0.35 mm, a spiral interval d = 0.2 mm, and a winding number 2.125. This is the case of the antenna element 23 having a circular spiral, and even when such a circular spiral antenna element 23 is used for the circularly polarized antenna 20, the result is almost the same as the case of using the square spiral antenna element 23 described above. Has been obtained.

  The outer shape of the dielectric substrate 21 is a square centered on the spiral center of the antenna element 23, and as shown in FIGS. 5A and 5B, the length of one side is L (hereinafter referred to as the outer length). ) And the outer shape of the cavity is a concentric square.

Further, as shown in FIGS. 7A and 7B, the cavity has an inner dimension Lw. Further, the frame-shaped conductor 32, a predetermined width extending from the cavity inner wall to the inside (hereinafter, referred to as rim width) rim having L _R is provided.

  The diameters of the plurality of metal posts 30 forming the cavity are each 0.3 mm, and the interval between the metal posts 30 is 0.9 mm.

  FIG. 11 shows a simulation result of the radiation characteristics of the vertical plane (the yz plane in FIGS. 4 and 5) in the case where the cavity and the frame-shaped conductor 32 by the plurality of metal posts 30 are not provided.

  In FIG. 11, F1 and F1 ′ are the characteristics of the main polarization (left-handed circular polarization: LHCP) and cross-polarization (right-handed circular polarization: RHCP) when the outer length L = 18 mm, and F2, F2 ′ is a characteristic of main polarization and cross polarization when the outer length L = 24 mm.

  Here, the radiation characteristic required for a circularly polarized antenna is a symmetric and broad single-peak characteristic with respect to the 0 ° direction for the main polarization. For some), the radiation intensity needs to be sufficiently lower than that of the main polarization in a wide angle range.

  On the other hand, the characteristics F1 and F2 of the main polarization in FIG. 11 are both asymmetric and have a large gain fluctuation, and in terms of cross polarization, the main polarization characteristics are in the vicinity of −60 ° and −40 °. It can be seen that the radiation level is equivalent or close to that.

  Such disturbance of radiation characteristics is caused by the influence of the surface wave described above.

FIG. 12 shows that when a cavity having an inner dimension Lw = 9 mm is provided by a plurality of metal posts 30 and a frame-like conductor 32 having a rim width L _R = 1.2 mm is provided, the outer lengths L = 18 mm and L = 24 mm. The simulation results for the main polarization characteristics F3 and F4 and the cross polarization characteristics F3 ′ and F4 ′ are shown.

  As is apparent from FIG. 12, the main polarization characteristics F3 and F4 are symmetric and broad single-peak characteristics around the 0 ° direction, and the cross-polarization characteristics F3 ′ and F4 ′ also have a wide angular range. In FIG. 4, it can be seen that it has a slow change with a radiation intensity sufficiently lower than that of the main polarizations F3 and F4, and that the desired characteristics required for the circularly polarized antenna described above are obtained.

  Further, as a result of simulations on various radiation characteristics similar to those described above performed by changing the structural parameters of each part, the radiation characteristics in the absence of the frame-shaped conductor 32 indicate that the outer length L of the dielectric substrate 21 and the cavity The dependence on the inner dimension Lw is shown, and the general tendency is that when the outer length L is large (L = 24, 18 mm), the main polarization characteristic becomes 3 as the cavity inner dimension Lw increases from 3 to 10 mm. It has been found that the peak shape approaches the single peak shape.

  Further, when the outer length L of the dielectric substrate 21 is relatively small (L = 12 mm), the main polarization characteristic approaches from a bimodal to a single peak as the cavity inner dimension Lw increases from 3 to 10 mm. It has been found.

  However, in any case, the cross-polarization fluctuation is large and the difference from the main polarization component is small in any of the use angle ranges, the polarization selectivity is low, and the desired characteristics as shown in FIG. It has been found that this is not possible.

The rim width _LR of 1.2 mm corresponds to approximately ¼ of the wavelength of the surface wave propagating along the surface of the dielectric substrate 21. That is, the portion of the rim width L _R = 1.2 mm has a length of λg / 4 (λg is an in-tube wavelength) where the impedance is infinite with respect to the surface wave when the post wall side is viewed from the tip side. The transmission path is formed.

  Therefore, no current flows along the surface of the dielectric substrate 21, and the excitation of the surface wave is suppressed by this current blocking action, thereby preventing the radiation characteristics from being disturbed.

Therefore, when applying a circularly polarized wave antenna 20 to the other frequency bands other than those described above may be changed setting the rim width L _R in accordance with the frequency.

  By the way, the circularly polarized wave antenna 20 of this embodiment forms a resonator by providing a cavity made of a plurality of metal posts 30 and a frame-shaped conductor 32 on a dielectric substrate 21, and this resonator is excited by an antenna element 23. You can think that you are.

  Since the circularly polarized antenna 20 of the present embodiment constitutes a resonator, a resonant frequency exists, and the input impedance of the circularly polarized antenna 20 becomes very large at that resonant frequency and does not radiate.

  In this case, the resonance frequency of the resonator is determined by the structural parameters of the resonator and the circularly polarized antenna element 23.

The structural parameters, as described above, internal dimension Lw of the cavity, in addition to the rim width L _R, the number of turns of the antenna element 23, the basic length a0 of the antenna element 23, and the like element width W of the antenna element 23.

  Therefore, the frequency characteristic of the antenna gain has a sudden deep drop (notch) near the resonance frequency. This resonance frequency can be set to a desired value by adjusting the above structural parameters.

  FIGS. 13A and 13B show an example of the positional relationship between the plurality of circularly polarized antennas 20 and the plurality of antennas 110 of the DUT 100 in the wireless terminal measurement apparatus 1 of the present embodiment. The plurality of circularly polarized antennas 20 are arranged at positions facing one surface of the DUT 100 and are spatially coupled to the antenna 110 installed on the one surface side of the DUT 100. The second circularly polarized antenna 20b is arranged at a position facing the surface and spatially coupled to the antenna 110 installed on the other surface side of the DUT 100.

  In other words, the first circularly polarized antenna 20 a has the opposite surface 21 b facing the radiation surface 110 a of the antenna 110 of the DUT 100 and one surface of the DUT 100. Further, the second circularly polarized antenna 20 b has the opposite surface 21 b facing the radiation surface 110 a of the antenna 110 of the DUT 100 and the other surface of the DUT 100.

  The opposite surface 21b of each circularly polarized antenna 20 is not parallel to the radiation surface 110a of each antenna 110 of the DUT 100, but is inclined by an inclination angle θ. That is, the normal line of one surface or the other surface of the DUT 100 where the plurality of antennas 110 are installed intersects the normal line of the opposite surface 21b of each circularly polarized antenna 20.

  Here, the normal line N2 of the radiation surface 110a of each antenna 110 and the normal line of one surface or the other surface of the DUT 100 where the plurality of antennas 110 are installed are parallel to each other. Further, the radiation direction of each antenna 110 is the normal direction of the radiation surface 110 a of each antenna 110.

  The normal line N1 of the opposite surface 21b of each circularly polarized antenna 20 and the normal line of the radiation surface of each circularly polarized antenna 20 are parallel. The radiation direction of each circularly polarized antenna 20 is the normal direction of the radiation surface of each circularly polarized antenna 20.

  That is, as shown in FIG. 13A, the radiation direction of the signal under measurement radiated from the radiation surface 110a of the antenna 110 is not parallel to the normal direction N1 of the opposite surface 21b of the circularly polarized antenna 20. . Therefore, the signal under measurement radiated from the radiation surface 110a of the antenna 110 is reflected between the circularly polarized antenna 20 and the antenna 110, travels toward the inner wall surface 50a of the terminal holder 50, and is absorbed by the inner wall surface 50a. The In this way, multiple reflection of the signal under measurement between the circularly polarized antenna 20 and the antenna 110 is suppressed.

  Similarly, as shown in FIG. 13B, the radiation direction of the test signal radiated from the antenna element 23 of the circularly polarized antenna 20 is not parallel to the normal direction N2 of the radiation surface 110a of the antenna 110. . Therefore, the test signal radiated from the circularly polarized antenna 20 is reflected between the circularly polarized antenna 20 and the antenna 110, travels toward the inner wall surface 50a of the terminal holder 50, and is absorbed by the inner wall surface 50a. In this way, multiple reflection of the test signal between the circularly polarized antenna 20 and the antenna 110 is suppressed.

  The circularly polarized antenna 20 is configured so that the signal under measurement can be satisfactorily received regardless of the direction of the linearly polarized wave of the signal under measurement transmitted from the antenna 110. Further, the circularly polarized antenna 20 has a characteristic that it is difficult to receive a signal from a circularly polarized antenna having a polarization rotation direction different from that of itself.

  In the present embodiment, the rotation direction of polarization differs between the first circularly polarized antenna 20a and the second circularly polarized antenna 20b. For example, the main polarization of the first circular polarization antenna 20a can be RHCP, and the main polarization of the second circular polarization antenna 20b can be LHCP. Or conversely, the main polarization of the first circular polarization antenna 20a can be LHCP, and the main polarization of the second circular polarization antenna 20b can be RHCP.

  In this manner, by changing the rotation direction of the polarization between the first circularly polarized antenna 20a and the second circularly polarized antenna 20b, a plurality of circularly polarized antennas 20 can be simultaneously used as shown in FIG. 13B. When the test signal is transmitted, it is possible to prevent the test signal transmitted from a certain circularly polarized antenna 20 from being received by the other circularly polarized antenna 20 facing the DUT 100.

  Note that the location and number of the circularly polarized antennas 20 in the terminal holder 50 are not limited to the examples shown in FIGS. 2, 3, and 13.

Hereinafter, the measurement results of S ₁₁ and S ₂₁ of the circularly polarized antenna 20 in the present embodiment will be described.

  Here, of the electromagnetic field radiated from the circularly polarized antenna 20, the region close to the circularly polarized antenna 20 is called a reactive near-field region mainly composed of electromagnetic field components that do not contribute to radiation. A region where the directivity does not change depending on the distance from the radiation surface of the circularly polarized antenna 20 is called a radiation far field region. A region between the reactive near-field region and the radiating far-field region is called a radiating near-field region, and is a region whose directivity changes according to the distance.

The near-field region of radiation is defined as a position away from the radiation surface of the circularly polarized antenna 20 by a distance R satisfying the following expression (1) with respect to the opening length D of the circularly polarized antenna 20. Here, λ is a free space wavelength.

  For example, if the aperture length D of the circularly polarized antenna 20 is 13 mm, the range R of the near-field region at 28 GHz, for example, is 8.9 mm to 31.6 mm according to the equation (1). The measurement results shown below were performed in a radiation near-field region or a reactive near-field region having a smaller propagation loss than the radiation far-field region.

As shown in FIG. 14 (a), two circularly polarized antennas 20 whose main polarization is RHCP are provided on a surface (that is, a dielectric substrate 21) on which an antenna element 23 is formed in a direction in which the extending direction of the feed line 28 is aligned. the opposite surface 21b) parallel to opposed state (below, in also referred) to as "facing state of 0 °", the results of measurement of the S ₁₁ and S ₂₁ by using a signal analyzer 70 in FIG. 15 and FIG. 16 Show.

Further, as shown in FIG. 14B, the surface of the two circularly polarized antennas 20 whose main polarization is RHCP, on which the antenna element 23 is formed in the direction in which the extending direction of the feed line 28 is vertical (that is, FIG. 17 shows the results of measuring S ₁₁ and S ₂₁ using the signal analysis device 70 in a state where the opposite surface 21b) of the dielectric substrate 21 faces in parallel (hereinafter also referred to as “90 ° facing state”). And shown in FIG.

Here, the signal analysis device 70 is configured by, for example, a network analyzer or a signal analyzer with a tracking generator function. Here the measurement of S ₁₁ and S ₂₁ in is the distance between the two circularly polarized antenna 20 that performed five times while the 2 cm. However, every time one measurement is completed, the next measurement is performed after the two circularly polarized antennas 20 are separated by an infinite distance.

From FIG. 15 to FIG. 18, the frequency characteristics of S ₁₁ and S ₂₁ obtained by five measurements almost overlap on the graph, and a highly reproducible measurement result is obtained for both S ₁₁ and S _21. I understand that. In addition, in the 90 ° facing state of FIG. 18, S ₂₁ dents near 28 GHz are seen, but this caused multiple reflections such that signal components in opposite phases cancel each other between the two circularly polarized antennas 20. Therefore, it is considered that an amplitude error has appeared.

19 and 20, in the opposing state of 0 °, is a graph showing measurement results of the S ₂₁ when the main polarization has changed the distance between the inclination angle θ between the two circularly polarized antenna 20 of the RHCP . Here, it is assumed that the distance between the two circularly polarized antennas 20 is the distance between the positions where the central axes of the feed pins 25 intersect on the opposite surface 21 b of the dielectric substrate 21 of each circularly polarized antenna 20.

FIG. 19 (a), the main polarization and 1cm distance between the two circularly polarized antenna 20 of the RHCP, the measurement results of the S ₂₁ when the inclination angle θ set to 0 °, an ellipse in FIG. As shown in the box, there is a dent due to an amplitude error in the vicinity of 25.5 GHz.

FIG. 19B shows the measurement result of S ₂₁ when the distance between the two circularly polarized antennas 20 whose main polarization is RHCP is 1 cm and the inclination angle θ is 5 °. As shown in the box, it can be seen that the dent in the vicinity of 25.5 GHz seen when θ = 0 ° is greatly improved.

FIG. 20A shows the measurement result of S ₂₁ when the distance between two circularly polarized antennas 20 whose main polarization is RHCP is 1.5 cm and the inclination angle θ is 0 °. As shown by surrounding with an ellipse, a dent due to an amplitude error is seen in the vicinity of 27.3 GHz.

FIG. 20B shows the measurement result of S ₂₁ when the distance between two circularly polarized antennas 20 whose main polarization is RHCP is 1.5 cm and the inclination angle θ is 5 °. It can be seen that the recess near 27.3 GHz, which was seen when θ = 0 °, disappears as shown by the oval.

Figure 21 is a transmission between the main direction of rotation of the polarization and transmission characteristics S ₂₁ between the two circularly polarized antenna 20 is the same, the main polarization direction of rotation two different circularly polarized antenna 20 characteristics S ₂₁ It is a graph which shows the result of having measured this using the signal analyzer 70. FIG.

Measurement of S ₂₁ here is a distance between the inclination angle between the two circularly polarized antenna 20 which was performed in a state where the respective 2cm and 5 °. Further, as shown in FIG. 14A, the two circularly polarized antennas 20 have a surface on which the antenna element 23 is formed so that the extending direction of the feed line 28 is aligned (that is, the opposite surface 21b of the dielectric substrate 21). ) Are facing each other.

From the graph of FIG. 21, compared with the transmission characteristic S ₂₁ (solid line) between the two circularly polarized antennas 20 whose main polarizations are both RHCP, two circularly polarized antennas whose main polarizations are RHCP and LHCP. It can be seen that the transmission characteristic S ₂₁ between 20 (dashed line) is as low as about 20 dB in the frequency range of 23 GHz or higher, indicating good isolation performance.

  In the wireless terminal measuring apparatus 1 of the present embodiment, the first circularly polarized antenna 20a and the second circularly polarized antenna 20b having different main polarization rotation directions are opposed to each other with the DUT 100 interposed therebetween. Even better isolation performance can be obtained between the wave antenna 20a and the second circularly polarized antenna 20b.

  Furthermore, in the measurement system shown in FIG. 14A, the residual EVM at 28.5 GHz when the distance and the inclination angle between the two circularly polarized antennas 20 are 2 cm and 5 °, respectively, as shown in FIG. became. That is, when both of the main polarizations of the two circularly polarized antennas 20 are RHCP as in the measurement systems A and B, when the two circularly polarized antennas 20 are measured in a shield box, There was no change in the residual EVM value when measured outside the shield box. Further, when one main polarization of the two circular polarization antennas 20 is LHCP and the other main polarization is RHCP as in the measurement systems C and D, the two circular polarization antennas 20 are shielded. There was no change in the value of residual EVM between the case of measurement in the box and the case of measurement outside the shield box.

Furthermore, measurement of the transmission characteristics S ₂₁ between the two circularly polarized antenna 20 in the measurement system to D, and when measured putting two circularly polarized antenna 20 in the shield box, measured outside the shield box in the case of a change in the transmission characteristic S ₂₁ it was observed.

  From the above, it can be seen that even in the terminal holder 50 of the wireless terminal measuring apparatus 1 of the present embodiment, the reflected waves from the plurality of circularly polarized antennas 20 do not cause an amplitude error.

  Hereinafter, an example of the process of the wireless terminal measurement method using the wireless terminal measurement apparatus 1 according to the present embodiment will be described with reference to the flowchart of FIG.

  First, the DUT 100 is held by the terminal holder 50 by the user (step S1).

  Next, the signal transmission unit 61 of the measurement unit 51 outputs a plurality of test signals to the DUT 100 simultaneously via the plurality of circularly polarized antennas 20 and the plurality of antennas 110 of the DUT 100 (signal transmission step S2).

  Next, the signal receiving unit 62 of the measuring unit 51 receives a plurality of signals to be measured output from the DUT 100 to which a plurality of test signals are input via the plurality of antennas 110 and the plurality of circularly polarized antennas 20 of the DUT 100. Receive (signal reception step S3).

  Next, the analysis processing unit 63 of the measurement unit 51 performs analysis processing corresponding to the communication standard of the DUT 100 on the plurality of signals under measurement received in the signal reception step S3 (analysis processing step S4).

  As described above, in the wireless terminal measurement device 1 according to this embodiment, the rotation direction of the polarization is different between the first circularly polarized antenna 20a and the second circularly polarized antenna 20b facing each other with the DUT 100 interposed therebetween. Therefore, the isolation performance between the opposing circular polarization antennas 20 can be maintained without installing an object that blocks a signal such as a shield material between the opposing circular polarization antennas 20.

  Further, in the wireless terminal measuring apparatus 1 according to the present embodiment, the radiation direction of the signal under measurement radiated from the radiation surface 110a of the antenna 110 is not parallel to the normal direction of the opposite surface 21b of the circularly polarized antenna 20. Therefore, the multiple reflection of the signal under measurement between the antenna 110 and the circularly polarized antenna 20 can be reduced. That is, the wireless terminal measurement apparatus 1 according to the present embodiment can perform measurement on the DUT 100 with high accuracy by suppressing the amplitude error caused by the multiple reflection occurring between the antenna 110 and the circularly polarized antenna 20. .

  Further, in the wireless terminal measuring apparatus 1 according to the present embodiment, the radiation direction of the test signal radiated from the antenna element 23 of the circularly polarized antenna 20 is not parallel to the normal direction of the radiation surface of the antenna 110. The multiple reflection of the test signal between the antenna 110 and the circularly polarized antenna 20 can be reduced.

  Moreover, since the opposite surface 21b of the circularly polarized antenna 20 is not parallel to the radiation surface of the antenna 110, the wireless terminal measuring apparatus 1 according to the present embodiment is between the antenna 110 and the circularly polarized antenna 20. Multiple reflections of the signal under measurement and the test signal can be reduced.

  Moreover, in the circularly polarized antenna 20 provided in the wireless terminal measuring apparatus 1 according to the present embodiment, the metal posts 30 penetrating the dielectric substrate 21 are arranged so as to surround the antenna element 23 to form a cavity structure. A frame-like conductor 32 is provided in which the tips of 30 are short-circuited along the alignment direction and extend a predetermined distance in the direction of the antenna element 23. Thereby, the circularly polarized wave antenna 20 can suppress the generation of surface waves, and can make the radiation characteristics of the antenna desired characteristics.

  Further, since the wireless terminal measuring apparatus 1 according to the present embodiment uses the circularly polarized antenna 20, the linearly polarized wave (for example, vertical polarization or horizontal polarization) of the signal under measurement radiated from the antenna 110 is used. Accurate measurement is possible regardless of orientation.

  Moreover, since the radio | wireless terminal measuring apparatus 1 which concerns on this embodiment measures in proximity | contact, it can measure with a sufficient precision, without using an anechoic chamber (chamber).

(Second Embodiment)
Next, a wireless terminal measurement device 2 according to the second embodiment of the present invention will be described with reference to the drawings. In addition, about the structure similar to 1st Embodiment, the same code | symbol is attached | subjected and description is abbreviate | omitted suitably. Also, description of operations similar to those in the first embodiment will be omitted as appropriate.

  As shown in FIG. 24, the wireless terminal measurement apparatus 2 of the present embodiment includes a belt conveyor (conveyance unit) 81, an electromagnetic wave shield box 82 as a measurement box, a drive control unit 83, a measurement unit 51, and a display unit. 52 and an operation unit 53.

  The electromagnetic wave shielding box 82 has an inlet 82a and an outlet 82b through which the DUT 100 is transported, and covers a space including at least a part of the transport path 81a. The electromagnetic shielding box 82 includes a plurality of circularly polarized antennas 20 (first circularly polarized antenna 20a and second circularly polarized antenna 20b) spatially coupled to the antenna 110 of the DUT 100, a detection unit 84, Is to be housed inside.

  The plurality of circularly polarized antennas 20 are in a state in which the entire DUT 100 is transported to the communicable region R, which will be described later. It arrange | positions in the electromagnetic wave shield box 82 so that it may be in the state which pinched | interposed DUT100 with the 1 circular polarization antenna 20a and the 2nd circular polarization antenna 20b.

  Further, the electromagnetic wave shielding box 82 is provided above the conveyance path 81a, and electromagnetic wave absorption that prevents electromagnetic waves generated by the plurality of antennas 110 or the plurality of circularly polarized antennas 20 of the DUT 100 from leaking from the inlet 82a and the outlet 82b. Electromagnetic wave absorbers 85a and 85b including a material are provided.

  The detection unit 84 includes, for example, a light source that emits a light beam and a light receiver that receives the light beam emitted from the light source, and the light receiver cannot receive the light beam while the light source emits the light beam. The so-called light projecting / receiving device or the like is detected, and the entry of the DUT 100 into the electromagnetic wave shielding box 82 can be detected. Further, when detecting the DUT 100, the detection unit 84 outputs a detection signal indicating that the DUT 100 has been detected to the determination unit 132 of the drive control unit 83 described later.

  The drive control unit 83 is constituted by, for example, a microcomputer or a personal computer including a CPU, a ROM, a RAM, an HDD, and the like constituting the storage unit 133, and by executing a predetermined program stored in the storage unit 133 in advance. The conveyance control unit 131 and the determination unit 132 are configured by software.

  The conveyance control unit 131 drives and controls the belt conveyor 81 and can change the conveyance speed according to the control signal output from the determination unit 132. The transport speed may always be constant.

  The storage unit 133 stores information on the size of the DUT 100, information on the communicable area R of the DUT 100, and the like. Here, the communicable region R is a region where each antenna 110 of the DUT 100 and each circularly polarized antenna 20 can be spatially coupled with sufficient strength, and electromagnetic wave absorbing portions 85a and 85b described later are in a closed state. It is set as an area that can be maintained.

  Based on the detection signal output from the detection unit 84, the information on the conveyance speed of the DUT 100 output from the conveyance control unit 131, and the information on the DUT 100 stored in the storage unit 133, the determination unit 132 determines that the entire DUT 100 is shielded from electromagnetic waves. It is determined whether or not it is transported to the communicable area R in the box 82. For example, the determination unit 132 determines the time required from when the detection signal is output from the detection unit 84 until the entire DUT 100 is within the communicable region R, and at least a part of the DUT 100 is outside the communicable region R. The above determination can be made by determining the time required to exit.

  Further, as already described, the determination unit 132 may output a control signal for changing the conveyance speed to the conveyance control unit 131. For example, the determination unit 132 determines the transport speed of the belt conveyor 81 when the entire DUT 100 is transported to the communicable region R in the electromagnetic wave shield box 82, and the communicable region R in which the entire DUT 100 is within the electromagnetic wave shield box 82. A control signal may be output that is slower than the transport speed when not transported.

  Alternatively, when the entire DUT 100 is transported to the communicable region R in the electromagnetic wave shield box 82, the determination unit 132 stops the transport by the belt conveyor 81 for a predetermined time and outputs a control signal for setting the transport speed to zero for a predetermined time. It may be output.

  Note that the above-described detection unit 84 may be configured by an imaging device. In this case, the determination unit 132 displays whether the entire DUT 100 is conveyed to the communicable region R in the electromagnetic wave shield box 82 or not. You may analyze by processing.

  The signal transmission unit 61 determines that the entire DUT 100 is determined to be conveyed to the communicable region R in the electromagnetic wave shield box 82 by the determination unit 132 of the drive control unit 83. In addition, a plurality of test signals are simultaneously output via a plurality of circularly polarized antennas 20 and a plurality of antennas 110 of the DUT 100.

  The signal receiving unit 62 receives a plurality of test signals on condition that the determination unit 132 of the drive control unit 83 determines that the entire DUT 100 is conveyed to the communicable region R in the electromagnetic wave shield box 82. The plurality of signals under measurement output from the DUT 100 are received via the plurality of antennas 110 and the plurality of circularly polarized antennas 20 of the DUT 100.

  By controlling the signal transmission unit 61 and the signal reception unit 62 as described above, the performance test is completed within the time in which the DUT 100 is accommodated in the electromagnetic wave shield box 82.

  FIG. 25 is a cross-sectional view of the belt conveyor 81 and the electromagnetic wave shield box 82 along the conveyance direction (Y direction) of the DUT 100. The belt conveyor 81 winds, for example, an endless belt 111 around a plurality of pairs of transport rollers 112a, 112b, 113a, 113b, and the DUT 100 is placed in the entrance of the electromagnetic wave shield box 82 in the transport path 81a of the upper portion of the belt 111. It conveys from the 82a side to the outlet 82b side.

  The belt conveyor 81 includes a motor 114 for rotating the belt 111 at one end in the axial direction of the transport roller 112b. The motor 114 is driven and controlled by the transport control unit 131.

  26 and 27 are perspective views showing examples of arrangement of the electromagnetic wave absorbers 85a and 85b in the electromagnetic wave shield box 82. FIG. FIG. 26 shows a configuration in which the belt 111 passes through the inlet 82a and the outlet 82b of the electromagnetic wave shield box 82 in the transport direction. On the other hand, FIG. 27 shows a configuration in which the electromagnetic wave shield box 82 has an opening on the bottom surface and the belt 111 always passes in the conveying direction so as to block the opening.

  Here, the housing 120 of the electromagnetic wave shielding box 82 is made of a conductive metal such as iron, stainless steel, aluminum, copper, brass, or an alloy thereof, and has an electromagnetic wave shielding function. The electromagnetic wave shield box 82 can be manufactured by bending a metal plate made of these materials. However, even if punching is performed on the plate made of these materials for weight saving and resource saving. Good. Or you may employ | adopt a net-like material instead of a board from the beginning. If the size of the hole or mesh is sufficiently smaller than the wavelength of the radio wave of the signal under measurement output from the DUT 100 (for example, 1/10 wavelength or less), the shielding performance as an electromagnetic wave shield box can be maintained.

  The belt 111 is preferably a conductive belt obtained by mixing a conductive substance or metal particles with cloth or rubber. Further, for example, a belt of iron, stainless steel, aluminum, copper, brass, or an alloy thereof may be processed into a structure that ensures elasticity that can be used for a conveyor. Or it is good also as a belt by laminating | stacking the above-mentioned metal net-like structure on the cloth and rubber | gum used for a conveyor.

  In the configuration of FIG. 26, the belt 111 does not necessarily need to be made of metal as long as shielding is sufficiently ensured by the electromagnetic wave shield box 82 and the conductive electromagnetic wave absorbers 85a and 85b. On the other hand, in the configuration of FIG. 27, it is necessary that the conductive belt 111 and the electromagnetic wave shield box 82 are in good contact with each other via a conductive slider or the like.

  When the DUT 100 passes through the inlet 82a or the outlet 82b of the electromagnetic wave shield box 82, the electromagnetic wave absorbers 85a and 85b open the inlet 82a or the outlet 82b, and the entire DUT 100 is conveyed into the electromagnetic wave shield box 82. In this case, the inlet 82a and the outlet 82b are closed.

  As shown in FIGS. 26 and 27, the electromagnetic wave absorbers 85a and 85b are provided in a plurality of strips in the horizontal direction (X direction) orthogonal to the transport direction (Y direction) in which the belt conveyor 81 transports the DUT 100. It consists of an electromagnetic shielding member. This electromagnetic wave shielding member is made of, for example, a cloth or rubber mixed with a conductive substance or metal particles, or a sheet of iron, stainless steel, aluminum, copper, brass, or an alloy thereof. The electromagnetic wave absorbers 85 a and 85 b configured as described above are provided suspended from the housing 120 so as to close the inlet 82 a and the outlet 82 b of the housing 120.

  As another example of the electromagnetic wave absorbers 85a and 85b, as shown in FIG. 28 and FIG. 29, a metal plate (FIG. 28) that can swing around a horizontal direction (X direction) orthogonal to the transport direction (Y direction). ) And a metal plate (FIG. 29) slidable in the vertical direction (Z direction) orthogonal to the transport direction (Y direction). These metal plates are driven by an arbitrary drive device based on detection information of the DUT 100 output from an arbitrary detection means.

  The location and number of the circularly polarized antennas 20 in the electromagnetic wave shield box 82 are not limited to the examples shown in FIGS. For example, it is possible to provide a configuration in which a plurality of sections are continuously provided in the conveyance direction of the DUT 100 of the electromagnetic wave shielding box 82 and the plurality of circularly polarized antennas 20 are disposed in each section.

  Hereinafter, an example of the processing of the wireless terminal measuring method using the wireless terminal measuring apparatus 2 according to the present embodiment will be described with reference to the flowchart of FIG.

  First, the conveyance control unit 131 of the drive control unit 83 conveys the DUT 100 in the conveyance path 81a (conveyance step S11).

  Next, the determination unit 132 of the drive control unit 83 determines whether or not the entire DUT 100 is transported to the communicable region R in the electromagnetic wave shield box 82 (determination step S12). As shown in FIG. 31A, when the DUT 100 is passing through the inlet 82a of the electromagnetic wave shield box 82, the detection unit 84 does not detect the DUT 100, and the determination unit 132 determines that the entire DUT 100 is the electromagnetic wave shield box 82. It is determined that it is not transported to the communicable area R.

  On the other hand, as shown in FIG. 31 (b), when the entire DUT 100 passes through the entrance 82a of the electromagnetic wave shield box 82 and the electromagnetic wave absorbers 85a and 85b are in the closed state, the detection output from the detection unit 84. Based on the signal, information on the conveyance speed of the DUT 100 output from the conveyance control unit 131, and information on the DUT 100 stored in the storage unit 133 of the drive control unit 83, the determination unit 132 determines that the entire DUT 100 is in the electromagnetic wave shield box 82. It is determined that it is transported to the communicable region R.

  Next, the signal transmission unit 61 of the measurement unit 51 determines that the entire DUT 100 is determined to be conveyed to the communicable region R in the determination step S12, and the DUT 100 conveyed by the belt conveyor 81 has a plurality of conditions. A plurality of test signals are simultaneously output via the circularly polarized antenna 20 and the plurality of antennas 110 of the DUT 100 (signal transmission step S13).

  Next, the signal receiving unit 62 of the measuring unit 51 outputs from the DUT 100 to which a plurality of test signals are input, on the condition that the entire DUT 100 is determined to be conveyed to the communicable region R in the determination step S12. The plurality of measured signals are received via the plurality of antennas 110 and the plurality of circularly polarized antennas 20 of the DUT 100 (signal reception step S14).

  Next, the analysis processing unit 63 of the measurement unit 51 performs analysis processing corresponding to the communication standard of the DUT 100 on the plurality of signals under measurement received in the signal reception step S14 (analysis processing step S15).

  That is, signals are transmitted and received between the circularly polarized antenna 20 and the antenna 110 of the DUT 100 only when the electromagnetic wave absorbers 85a and 85b are closed and the DUT 100 is transported to the communicable region R. It has become.

  As shown in FIG. 31C, when the DUT 100 is passing through the outlet 82b of the electromagnetic wave shield box 82 and the electromagnetic wave absorbing portion 85b on the outlet 82b side is in the open state, the above-described detection signal, DUT 100 Based on the transport speed information and the DUT 100 information, the determination unit 132 determines that the entire DUT 100 is not transported to the communicable region R in the electromagnetic wave shield box 82. At this time, it is desirable from the viewpoint of measurement efficiency that another DUT 100 is passing through the inlet 82a of the electromagnetic wave shielding box 82 at the same time.

  As described above, the wireless terminal measurement device 2 according to the present embodiment automatically determines that the entire DUT 100 is transported to a predetermined area in the electromagnetic wave shield box 82 and starts a performance test on the DUT 100. Therefore, a performance test can be performed on various wireless terminals, and the test time can be greatly shortened.

  In addition, the wireless terminal measurement device 2 according to the present embodiment eliminates the need to connect the DUT 100 and the measurement device with a cable, and does not require the DUT 100 to be manually inserted into and removed from the electromagnetic wave shield box 82. It can be greatly shortened.

  In addition, since the wireless terminal measuring apparatus 2 according to the present embodiment does not require a dedicated jig for cable connection, a measuring instrument can be shared in a factory that manufactures various types of wireless devices, and the test cost can be reduced. Mitigation is possible.

  In the scope of the present invention, the measurement unit 51 and the belt conveyor 81 in this embodiment can operate as a measurement device and a conveyance device independent of each other, and these are external control devices including the function of the drive control unit 83. A controlled configuration is also included.

  In the wireless terminal measurement apparatus 2 according to the present embodiment, the antenna 110 and the circularly polarized antenna 20 of the DUT 100 are close to each other even if a measurement box having no electromagnetic wave shielding function is used instead of the electromagnetic wave shielding box 82. Since the measurement is performed by arrangement, leakage of electromagnetic waves is sufficiently prevented. The wireless terminal measuring apparatus 2 according to the present embodiment can further obtain an electromagnetic wave shielding effect by including the electromagnetic wave shield box 82 and the electromagnetic wave absorbers 85a and 85b.

DESCRIPTION OF SYMBOLS 1, 2 Radio | wireless terminal measuring device 20 Circularly polarized wave antenna 20a 1st circularly polarized wave antenna 20b 2nd circularly polarized wave antenna 21 Dielectric substrate 21a One side 21b Opposite side 22 Ground plane conductor 23 Antenna element 25 Feeding pin 26 Feeding part 27 Feeding part Dielectric substrate 28 Feed line 30 Metal post 32 Frame conductor 61 Signal transmitter 62 Signal receiver 63 Analysis processor 81 Belt conveyor 81a Transport path 82 Electromagnetic shield box 82a Inlet 82b Outlet 85a, 85b Electromagnetic wave absorber 100 DUT
110 Antenna 110a Radiation surface 132 Judgment part

Claims (8)

Wireless terminal measuring device (1, 2) for measuring a test object (100) having a plurality of antennas (110) including an antenna installed on one side and another antenna installed on the other side Because
A first circularly polarized antenna (20a) disposed at a position facing one surface of the object to be tested and spatially coupled to the antenna (110) installed on the one surface side of the object to be tested; A second circularly polarized antenna (20b) disposed at a position facing the other surface of the object under test and spatially coupled to the antenna (110) installed on the other surface side of the object under test; A plurality of circularly polarized antennas (20) including:
A signal transmission unit (61) for simultaneously outputting a plurality of test signals to the device under test via the plurality of circularly polarized antennas and the plurality of antennas (110) ;
A signal receiving unit (62) for receiving a plurality of signals to be measured output from the test object to which the plurality of test signals are input via the plurality of antennas (110) and the plurality of circularly polarized antennas; ,
An analysis processing unit (63) for performing analysis processing on the plurality of signals under measurement received by the signal receiving unit,
The circularly polarized antenna is
A dielectric substrate (21);
A ground plane conductor (22) superposed on one surface (21a) side of the dielectric substrate;
A circularly polarized antenna element (23) formed on the opposite surface (21b) of the dielectric substrate facing one surface or the other surface of the object to be tested, and having a predetermined polarization rotation direction;
Each one end side is connected to the ground plane conductor, penetrates the dielectric substrate along its thickness direction, and each other end side extends to the opposite surface of the dielectric substrate so as to surround the antenna element. A plurality of metal posts (30) constituting a cavity by being provided at a predetermined interval;
A frame-like conductor having a rim having a predetermined width in the direction of the antenna element, the other end of each of the plurality of metal posts being short-circuited along the arrangement direction on the opposite surface side of the dielectric substrate. 32), and
A resonator is constituted by the cavity and the frame-shaped conductor, a structural parameter of the resonator and the antenna element is adjusted, a resonance frequency of the resonator is set to a desired value, and the structural parameter is: Including at least one of an inner dimension Lw of the cavity, the rim width L _R of the frame-shaped conductor, the number of turns of the antenna element, a basic length a0 of the antenna element, and an element width W of the antenna element, and the frame the rim width of Jo conductor L _R is a width of approximately 1/4 of the wavelength of a surface wave propagating along the surface of the dielectric substrate,
The normal of one surface or the other surface of the object under test where the plurality of antennas (110) are installed intersects the normal of the opposite surface of the dielectric substrate of each circularly polarized antenna,
The wireless terminal measurement apparatus, wherein the rotation direction of the predetermined polarization is different between the first circular polarization antenna and the second circular polarization antenna. The normal of the radiation surface of each antenna (110) and the normal of one surface or the other surface of the object under test where the plurality of antennas (110) are installed are parallel,
Radial direction of each said antenna (110) the wireless terminal measuring device according to claim 1, characterized in that the normal direction of the emission surface of each said antenna (110).   The normal to the opposite surface of the dielectric substrate of each circularly polarized antenna and the normal to the radiation surface of each circularly polarized antenna are parallel, and the radiation direction of each circularly polarized antenna is The wireless terminal measurement device according to claim 1, wherein the wireless terminal measurement device is in a normal direction of a radiation surface of the wave antenna. The antenna element is formed in a square spiral type or a circular spiral type having a center side end of a spiral,
A feeding pin (25) provided at one end of the antenna element formed in the rectangular spiral type or the circular spiral type with one end connected to the center side end of the spiral and penetrating the dielectric substrate and the ground plane conductor. The radio | wireless terminal measuring device in any one of Claims 1-3 characterized by the above-mentioned. A transport section (81) for transporting the test object in a transport path (81a);
A measurement box (82) containing the circularly polarized antenna therein, having an inlet (82a) and an outlet (82b) for transporting the object to be tested;
A determination unit (132) for determining whether or not the entire object to be tested is transported to a predetermined area in the measurement box;
The signal transmission unit may be configured to apply the plurality of circular deviations to the test target transported by the transport unit on the condition that the determination unit determines that the entire test target is transported to the predetermined area. Outputting the plurality of test signals simultaneously via a wave antenna and the plurality of antennas (110) ;
The signal receiving unit is output from the test target to which the plurality of test signals are input, on condition that the determination unit determines that the entire test target is conveyed to the predetermined area. The wireless terminal measurement apparatus according to claim 1, wherein the plurality of signals under measurement are received via the plurality of antennas (110) and the plurality of circularly polarized antennas. . Electromagnetic wave absorbers (85a, 85b) that are provided above the conveyance path and prevent electromagnetic waves generated by the plurality of antennas (110) or the plurality of circularly polarized antennas from leaking from the inlet and the outlet. In addition,
The wireless terminal measurement device according to claim 5, wherein the measurement box has an electromagnetic wave shielding function. A wireless terminal measurement method using the wireless terminal measurement device according to any one of claims 1 to 4,
A signal transmission step (S2) for simultaneously outputting the plurality of test signals to the object under test via the plurality of circularly polarized antennas and the plurality of antennas (110) ;
A signal receiving step (S3) for receiving the plurality of signals under measurement output from the object under test to which the plurality of test signals are input via the plurality of antennas (110) and the plurality of circularly polarized antennas. When,
An analysis processing step (S4) for performing analysis processing on the plurality of signals under measurement received in the signal reception step. A wireless terminal measurement method using the wireless terminal measurement device according to claim 5 or 6,
A transport step (S11) for transporting the test object in the transport path;
A determination step (S12) for determining whether or not the entire object to be tested is transported to a predetermined area in the measurement box;
The plurality of circularly polarized antennas and the plurality of the plurality of circularly polarized antennas are transported to the test target transported by the transport unit on the condition that the determination step determines that the entire test target is transported to the predetermined area. A signal transmission step (S13) for simultaneously outputting the plurality of test signals via the antenna (110) ;
The plurality of measurement targets output from the test target to which the plurality of test signals are input on condition that the determination step determines that the entire test target is conveyed to the predetermined area. A signal receiving step (S14) for receiving a signal via the plurality of antennas (110) and the plurality of circularly polarized antennas;
An analysis processing step (S15) for performing analysis processing on the plurality of signals under measurement received in the signal reception step.

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