Antenna module test apparatus, test system, and test method

Abstract

This invention provides an antenna module test apparatus capable of suppressing the narrowing of the dynamic range during loopback testing. [Solution] The antenna module under test has the function of transmitting and receiving first and second polarizations that are orthogonal to each other. For the transmit and receive signals input and output to the first terminal, the gain of the first polarization is greater than the gain of the second polarization, and for the transmit and receive signals input and output to the second terminal, the gain of the second polarization is greater than the gain of the first polarization. A reflector is placed at the position where radio waves radiated from the antenna module under test are incident. The reflector converts the incident radio waves into a polarization orthogonal to the polarization of the incident radio waves and reflects it toward the antenna module under test. A first signal processing circuit is connected to the first terminal and inputs the transmit signal to the first terminal. A second signal processing circuit is connected to the second terminal and processes the received signal output from the second terminal.

Description

Technical Field

[0001] The present invention relates to an antenna module test apparatus, a test system, and a test method.

Background Art

[0002] In order to test whether an antenna module is functioning properly, a loopback test (see Patent Document 1) may be performed. In the loopback test described in Patent Document 1, for example, a test radio wave is radiated from an antenna module with horizontal polarization, and the radio wave reflected by a reflector is received with vertical polarization. Based on the gain of the received signal, it is determined whether the antenna module is functioning as expected.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] When a test radio wave is radiated from an antenna module with horizontal polarization, the reflected wave reflected by a reflector is also mainly horizontally polarized. Therefore, when the reflected wave is received with vertical polarization, the received level becomes extremely low, and it is impossible to ensure a sufficiently wide dynamic range in measurement. An object of the present invention is to provide an antenna module test apparatus, a test system, and a test method capable of suppressing a narrowing of the dynamic range in a loopback test.

Means for Solving the Problems

[0005] According to one aspect of the present invention, A test apparatus for an antenna module having the function of transmitting and receiving a first polarization and a second polarization that are mutually orthogonal to each other, wherein for the transmit and receive signals input and output to the first terminal, the gain of the first polarization is greater than the gain of the second polarization, and for the transmit and receive signals input and output to the second terminal, the gain of the second polarization is greater than the gain of the first polarization, A reflector is placed at the position where radio waves emitted from the antenna module under test enter, and converts the incident radio waves into a polarization perpendicular to the polarization of the incident radio waves and reflects them back toward the antenna module under test. A first signal processing circuit connected to the first terminal and inputting a transmission signal to the first terminal, A second signal processing circuit connected to the second terminal and processing the received signal output from the second terminal, An antenna module test apparatus equipped with [the specified feature] is provided.

[0006] According to another aspect of the present invention, An antenna module having a first radiating element and a second radiating element with different boresite directions, A first reflector and a second reflector are arranged in the direction of the boresites of the first and second radiating elements, respectively, and convert the incident radio waves into a polarization perpendicular to the polarization of the incident radio waves and reflect them toward the first and second radiating elements. Equipped with, The aforementioned antenna module is First terminal and, The second terminal and For the transmit and receive signals input and output to the first terminal, the gain of the first radiating element for the first polarization is greater than the gain of the second polarization which is orthogonal to the first polarization, and the gain of the second radiating element for the first polarization is less than the gain of the second polarization. For the transmit and receive signals input and output to the second terminal, the gain of the first radiating element for the second polarization is greater than the gain of the first polarization, and the gain of the second radiating element for the first polarization is less than the gain of the second polarization. A high-frequency integrated circuit that drives the first radiating element and the second radiating element is configured such that, for the transmit and receive signals input and output to the first terminal, the gain of the first radiating element for the second polarization is greater than the gain of the first polarization, and the gain of the second radiating element for the first polarization is less than the gain of the second polarization. Includes, moreover, A first signal processing circuit connected to the first terminal and inputting a transmission signal to the first terminal, A second signal processing circuit connected to the second terminal and processing the received signal output from the second terminal, An antenna module test system equipped with the following features is provided.

[0007] According to yet another aspect of the present invention, The antenna module under test is made to radiate the first polarization, The first polarization radiated from the antenna module is converted to a polarization orthogonal to the first polarization and reflected, The reflected radio waves are received by the antenna module, An antenna module testing method is provided for evaluating the quality of the antenna module based on the reception results. [Effects of the Invention]

[0008] Because the reflector converts the incident radio waves into a polarization orthogonal to the polarization of the incident radio waves, the signal transmitted from the first signal processing circuit can be received by the second signal processing circuit with a sufficiently high gain. This makes it possible to suppress the narrowing of the dynamic range in loopback testing. [Brief explanation of the drawing]

[0009] [Figure 1] Figure 1 is a schematic diagram of an antenna module test apparatus according to the first embodiment. [Figure 2] Figure 2 is a perspective view of the reflector 30. [Figure 3] Figure 3 is a block diagram of the antenna module 10 under test. [Figure 4] Figure 4 is a flowchart showing the procedure of the test method according to the first embodiment. [Figure 5]FIG. 5 is a graph showing the measurement results of return loss when transmitting and receiving the same polarization, and VH isolation when the polarization is made different between transmission and reception. [Figure 6] FIGS. 6A and 6B are schematic cross-sectional views of the reflector 30 of the antenna module test apparatus according to a modification of the first embodiment. [Figure 7] FIG. 7 is a schematic perspective view of the reflector 30 of the antenna module test apparatus according to the second embodiment. [Figure 8] FIG. 8 is a schematic plan view of the reflector 30 of the antenna module test apparatus according to the third embodiment. [Figure 9] FIG. 9A is a cross-sectional view of the antenna module test apparatus according to the fourth embodiment and the antenna module 10 to be tested, and FIG. 9B is a cross-sectional view of the antenna module test apparatus and the antenna module 10 in a state of performing a loopback test. [Figure 10] FIG. 10 is a schematic view of the antenna module test apparatus according to the fifth embodiment. [Figure 11] FIG. 11 is a schematic cross-sectional view specifically showing the structure of the antenna module test apparatus according to the fifth embodiment. [Figure 12] FIG. 12 is a schematic view of the antenna module test system according to the sixth embodiment. [Figure 13] FIG. 13 is a block diagram of the antenna module test system according to the sixth embodiment. [Figure 14] FIG. 14 is a block diagram of the antenna module test apparatus according to the seventh embodiment and the antenna module 10 to be tested. [Figure 15] FIG. 15 is a block diagram of the antenna module test apparatus according to a modification of the seventh embodiment and the antenna module 10 to be tested.

BEST MODE FOR CARRYING OUT THE INVENTION

[0010] [First Embodiment] The antenna module test apparatus and test method according to the first embodiment will be described with reference to the drawings from FIG. 1 to FIG. 5.

[0011] Figure 1 is a schematic diagram of an antenna module test apparatus according to the first embodiment. The antenna module test apparatus according to the first embodiment includes a reflector 30, a first signal processing circuit 40A, and a second signal processing circuit 40B, and performs a loopback test on the antenna module 10.

[0012] First, let's briefly describe the antenna module 10 under test. The antenna module 10 includes a substrate 28, a plurality of radiating elements 26 formed on the substrate 28, a high-frequency integrated circuit (RFIC) 25, a first terminal T1, and a second terminal T2. The antenna module 10 has the function of transmitting and receiving a first polarization and a second polarization that are mutually orthogonal to each other. The first polarization and the second polarization are linear polarizations whose polarization planes are mutually orthogonal. For example, the first polarization is vertical polarization (V polarization) and the second polarization is horizontal polarization (H polarization). Below, we will describe an example in which the first polarization and the second polarization are V polarization and H polarization, respectively.

[0013] For the transmit and receive signals input and output to the first terminal T1, the gain of the V-polarization is greater than the gain of the H-polarization, and for the transmit and receive signals input and output to the second terminal T2, the gain of the H-polarization is greater than the gain of the V-polarization. Typically, when a high-frequency signal is input to the first terminal T1, the antenna module 10 radiates V-polarization, and when the antenna module 10 receives V-polarization, it outputs the received high-frequency signal from the first terminal T1. When a high-frequency signal is input to the second terminal T2, the antenna module 10 radiates H-polarization, and when the antenna module 10 receives H-polarization, it outputs the received high-frequency signal from the second terminal T2.

[0014] The RFIC25 has the function of upconverting the intermediate frequency signal input to the first terminal T1 or the second terminal T2 and distributing and supplying it to multiple radiating elements 26. Furthermore, the RFIC25 has the function of combining and downconverting the high-frequency signals received by the multiple radiating elements 26 and outputting the generated intermediate frequency signal from the first terminal T1 or the second terminal T2. In the case of a direct conversion method, the baseband signal is upconverted to generate the transmission signal, and the received signal is downconverted to generate the baseband signal. An example using an intermediate frequency signal will be described below.

[0015] The first signal processing circuit 40A has the function of inputting the intermediate frequency signal to be transmitted to the first terminal T1. The second signal processing circuit 40B has the function of processing the intermediate frequency signal output from the second terminal T2. Furthermore, the first signal processing circuit 40A may also have the function of processing the intermediate frequency signal output from the first terminal T1. The second signal processing circuit 40B may also have the function of inputting the intermediate frequency signal to be transmitted to the second terminal T2. The first signal processing circuit 40A and the second signal processing circuit 40B can perform input and output of intermediate frequency signals independently of each other.

[0016] The reflector 30 is positioned where radio waves emitted from the antenna module 10 under test are incident. Multiple grooves 31 are provided on the surface of the reflector 30 that is incident on the radio waves. The reflector 30 converts the incident radio waves into a polarization perpendicular to the polarization of the incident radio waves and reflects them. For example, if V-polarized waves are incident on the reflector, the reflected wave will be H-polarized, and if H-polarized waves are incident, the reflected wave will be V-polarized.

[0017] Figure 2 is a perspective view of the reflector 30. The reflector 30 is made of a metal plate with a plurality of grooves 31 on one surface (the surface to which the radio waves are incident). The plurality of grooves 31 extend in a direction that forms a 45° angle with respect to the polarization plane of the V-polarization or H-polarization incident on the reflector 30 and are arranged at equal intervals. The depth of each of the plurality of grooves 31 is 1 / 4 of the wavelength of the radio waves radiated from the antenna module 10. In addition, the width and spacing of each of the grooves 31 are smaller than the depth of the grooves 31, for example, about 1 / 10 of the wavelength of the incident radio waves.

[0018] The groove 31 may be filled with a dielectric material. In this case, the depth of the groove 31 should be 1 / 4 of the wavelength of the radio waves radiated from the antenna module 10 within the dielectric.

[0019] Figure 3 is a block diagram of the antenna module 10 under test. The antenna module 10 includes an RFIC 25 and a plurality of radiating elements 26. The radiating elements 26, together with the ground conductor, constitute a patch antenna. Although four radiating elements 26 are shown in Figure 3, there may be two, three, or five or more radiating elements 26. Each of the radiating elements 26 has a first feed point 27A and a second feed point 27B. In Figure 3, the first feed point 27A is represented by a solid circle symbol, and the second feed point 27B is represented by a hollow circle symbol. For example, when power is supplied to the first feed point 27A, V-polarized waves are radiated from the radiating element 26, and when power is supplied to the second feed point 27B, H-polarized waves are radiated from the radiating element 26.

[0020] The baseband integrated circuit (BBIC) 40 includes a first signal processing circuit 40A and a second signal processing circuit 40B. The first terminal T1 and the second terminal T2 of the antenna module 10 are connected to the first signal processing circuit 40A and the second signal processing circuit 40B, respectively.

[0021] The RFIC25 includes a first transceiver circuit 21A connected to a first terminal T1 and a second transceiver circuit 21B connected to a second terminal T2. The first transceiver circuit 21A and the second transceiver circuit 21B have the same configuration. Each of the first transceiver circuit 21A and the second transceiver circuit 21B includes an amplifier 11, an up / down converter mixer 12, a transceiver selector switch 13, a power divider 14, multiple phase shifters 15, multiple attenuators 16, multiple transceiver selector switches 17, multiple power amplifiers 18, multiple low-noise amplifiers 19, and multiple transceiver selector switches 20.

[0022] Each contact of the multiple transmit / receive selector switches 20 in the first transmit / receive circuit 21A is connected to the first feed point 27A of the radiating element 26. Each contact of the multiple transmit / receive selector switches 20 in the second transmit / receive circuit 21B is connected to the second feed point 27B of the radiating element 26.

[0023] Next, the transmission function of the first transmit / receive circuit 21A will be described. An intermediate frequency signal is input from the first signal processing circuit 40A to the up / down convert mixer 12 via the first terminal T1 and amplifier 11. The up / down convert mixer 12 upconverts the intermediate frequency signal to generate a high-frequency transmission signal. The generated high-frequency transmission signal is input to the power divider 14 via the transmit / receive selector switch 13. Each of the high-frequency transmission signals distributed by the power divider 14 is supplied to the first feed point 27A of the radiating element 26 via the phase shifter 15, attenuator 16, transmit / receive selector switch 17, power amplifier 18, and transmit / receive selector switch 20. Therefore, when an intermediate frequency transmission signal is input from the first signal processing circuit 40A, V-polarization is radiated from the radiating element 26.

[0024] Next, the receiving function of the first transmitting / receiving circuit 21A will be described. When V-polarization is incident on the radiating element 26, the high-frequency received signal received by each of the radiating elements 26 is input to the power divider 14 via the first feed point 27A, the transmit / receive selector switch 20, the low-noise amplifier 19, the transmit / receive selector switch 17, the attenuator 16, and the phase shifter 15.

[0025] The high-frequency received signal synthesized by the power divider 14 is input to the up / down converter mixer 12 via the transmit / receive selector switch 13. The up / down converter mixer 12 down-converts the high-frequency received signal to generate an intermediate frequency signal. The generated intermediate frequency signal is input to the first signal processing circuit 40A via the amplifier 11 and the first terminal T1.

[0026] The second transmitting / receiving circuit 21B has the same function as the first transmitting / receiving circuit 21A. When a transmission signal is supplied from the second signal processing circuit 40B to the radiating element 26 via the second transmitting / receiving circuit 21B, H-polarized waves are emitted from the radiating element 26. When H-polarized waves are incident on the radiating element 26, a reception signal is input to the second signal processing circuit 40B via the second transmitting / receiving circuit 21B.

[0027] Next, with reference to Figure 4, a test method using the antenna module test apparatus according to the first embodiment will be described. Figure 4 is a flowchart showing the procedure of the test method according to the first embodiment.

[0028] First, the first signal processing circuit 40A outputs a transmission signal, causing one radiating element 26 to radiate V-polarization (Step S1). The radio waves radiated from one radiating element 26 are reflected by the reflector 30 (Figure 1), and the reflected waves converted to H-polarization are received by the antenna module 10 (Figure 1) (Step S2). The received signal received by the antenna module 10 is input to the second signal processing circuit 40B, and the second signal processing circuit 40B performs signal processing on the received signal (Step S3). Based on the reception results, the transmit and receive function of the antenna module 10 is evaluated (Step S4). For example, if the signal level of the received signal is as expected relative to the signal level of the transmitted signal, the antenna module 10 is determined to be functioning correctly.

[0029] Next, we will describe the excellent effects of the first embodiment. In the first embodiment, a loopback test can be performed by outputting a transmission signal from the first signal processing circuit 40A, receiving radio waves reflected by the reflector 30, and performing signal processing on the received signal in the second signal processing circuit 40B.

[0030] The antenna module 10 is designed to have high isolation between mutually orthogonal V-polarization and H-polarization. Therefore, when the first signal processing circuit 40A is operated from the antenna module 10 to radiate V-polarization and the reflected V-polarization wave is received by the second signal processing circuit 40B, the reception level becomes low. As a result, the dynamic range of the measurement system becomes narrow.

[0031] In contrast, in the first embodiment, the reflector 30 converts V-polarization to H-polarization, so the reception level of the received signal received by the second signal processing circuit 40B, which has a high gain for H-polarization, becomes higher. Therefore, it is possible to realize a measurement system with a wide dynamic range.

[0032] Next, we will explain the return loss and VH isolation during the loopback test with reference to Figure 5.

[0033] Figure 5 is a graph showing the measurement results of return loss when transmitting and receiving with the same polarization, and VH isolation when the polarizations for transmission and reception are different. The horizontal axis of each graph represents frequency in units of [GHz]. The tests were conducted with high-frequency signals at two frequencies: 28 GHz and 39 GHz.

[0034] The vertical axis of the upper graph represents the return loss in units of [dB]. Circles indicate the return loss when transmitting with V polarization, and triangles indicate the return loss when transmitting with H polarization. A high return loss means that the reception level of the reflected wave with the same polarization as the transmitted radio wave is high.

[0035] The vertical axis of the graph below represents the VH coupling degree in units of [dB]. Circles indicate the VH coupling degree when H polarization is emitted and V polarization is received, while triangles indicate the VH coupling degree when V polarization is emitted and H polarization is received. A high VH coupling degree means that the reception level of reflected waves with polarization perpendicular to the polarization of the transmitted radio wave is high.

[0036] Measurements were performed for the antenna alone, with a metal plate as the reflector, and with the reflector 30 (Figure 2) according to the first embodiment as the reflector. The depth of the groove 31 in the reflector 30 was set to 1 / 4 of the wavelength of the 28 GHz radio wave. Therefore, when a 28 GHz V-polarized wave is incident on the reflector 30, almost all of the incident wave is converted to H-polarized wave. When a 39 GHz radio wave is incident, some components of the incident wave are converted to H-polarized wave, but the remaining components remain V-polarized.

[0037] This section describes the case of transmitting and receiving high-frequency signals at a frequency of 28 GHz. When a metal plate reflector is placed, the return loss is greater compared to the case of the antenna alone. This means that the transmitted signal was reflected by the reflector while maintaining its polarization. When a reflector that performs polarization conversion is placed, the return loss is almost the same as that of the antenna alone. This means that there were almost no reflected waves with the same polarization as the transmitted radio waves.

[0038] The VH coupling degree does not differ significantly between the case of a single antenna and the case of a metal plate reflector. This means that there are almost no reflected waves with polarization perpendicular to the polarization of the transmitted radio wave. When a reflector that performs polarization conversion is placed, the VH coupling degree becomes significantly larger compared to the case of a single antenna. This means that the polarization of the transmitted radio wave is converted to a polarization perpendicular to the antenna and reflected.

[0039] In the first embodiment, the measurement is performed in the state shown in the lower right graph of Figure 5. That is, V-polarization is transmitted and H-polarization is received. Comparing the lower right graph with the lower center graph, it can be seen that the reception level of H-polarization is significantly higher. As a result, a measurement system with a wide dynamic range is realized. Alternatively, H-polarization may be transmitted and V-polarization received.

[0040] When transmitting and receiving high-frequency signals with a frequency of 39 GHz, the clear trend seen when using high-frequency signals with a frequency of 28 GHz is not observed. This is because the depth of the groove 31 of the reflector 30 (Figures 1 and 2) is set to correspond to the high-frequency signal with a frequency of 28 GHz. If the depth of the groove 31 is set to correspond to the high-frequency signal with a frequency of 39 GHz, the same trend as in the case of 28 GHz can be obtained even at a frequency of 39 GHz.

[0041] Next, a preferred range for the depth of the grooves 31 of the reflector 30 will be described. Preferably, the depth of each of the multiple grooves 31 is at least 1 / 4 of the wavelength of the upper limit frequency of the operating frequency band of the antenna module 10 under test, and at least 1 / 4 of the wavelength of the lower limit frequency. By adopting such a configuration, the effect of increasing the degree of VH coupling to a certain extent can be obtained at any frequency in the operating frequency band.

[0042] For example, the millimeter-wave operating frequency in the fifth-generation mobile communication system (5G) is between 24.25 GHz and 43.5 GHz. One-quarter of the wavelength in this operating frequency band is between 1.72 mm and 3.09 mm. Therefore, in order to test the antenna module 10 operating in the millimeter-wave operating frequency band of 5G, it is advisable to select the depth of the groove 31 of the reflector 30 from the range of 1.72 mm to 3.09 mm.

[0043] Next, with reference to Figures 6A and 6B, a reflector of an antenna module test apparatus according to a modification of the first embodiment will be described. Figures 6A and 6B are schematic cross-sectional views of the reflector 30 of the antenna module test apparatus according to a modification of the first embodiment. In the first embodiment, the depth of the groove 31 of the reflector 30 (Figure 2) is fixed. In contrast, the reflector 30 of the antenna module test apparatus according to this modification has a depth variable mechanism 32 that changes the depth of multiple grooves 31.

[0044] For example, the reflector 30 includes a groove side surface component 30a and a groove bottom surface component 30b. The groove side surface component 30a constitutes the sides of multiple grooves 31, and the groove bottom surface component 30b constitutes the bottom surface of the grooves 31. The depth variable mechanism 32 displaces the groove bottom surface component 30b relative to the groove side surface component 30a in the depth direction of the grooves 31. When the groove bottom surface component 30b is displaced in the depth direction of the grooves 31, the depth of the grooves 31 changes. Figure 6B shows a state in which the depth of the grooves 31 is relatively deeper than in Figure 6A.

[0045] As shown in this modified example, by making the depth of the groove 31 of the reflector 30 variable, it becomes possible to optimize the depth of the groove 31 of the reflector 30 at any frequency in the operating frequency band of the antenna module 10. The reflector 30 according to this modified example can also be used for measurements of multiband antenna modules and wideband antenna modules.

[0046] For example, when testing an antenna module 10 operating in the 28GHz and 39GHz bands of 5G, it is preferable to use a reflector 30 in which the depth of the groove 31 can be varied between 2.68mm, which is one-quarter of the wavelength of 10.71mm corresponding to the frequency of 28GHz, and 1.92mm, which is one-quarter of the wavelength of 7.69mm corresponding to the frequency of 39GHz.

[0047] Note that the configuration of the depth variable mechanism 32 shown in Figures 6A and 6B is just one example, and any configuration can be used as long as the depth of the groove 31 can be changed. For example, instead of the groove bottom component 30b, the groove side component 30a may be made displaceable, or both the groove bottom component 30b and the groove side component 30a may be made displaceable.

[0048] [Second Example] Next, with reference to Figure 7, the antenna module test apparatus according to the second embodiment will be described. Hereafter, the configurations common to the antenna module test apparatus according to the first embodiment, which was described with reference to Figures 1 to 5, will be omitted from the explanation.

[0049] Figure 7 is a schematic perspective view of the reflector 30 of the antenna module test apparatus according to the second embodiment. In the second embodiment, a quad-ridge horn antenna 35 is used as the reflector 30. The quad-ridge horn antenna 35 has an input / output port 35V for V polarization and an input / output port 35H for H polarization. Input / output port 35V and input / output port 35H are connected by a transmission line 36. For example, input / output port 35V and input / output port 35H are coaxial connectors, and a coaxial cable is used as the transmission line 36.

[0050] For example, when V-polarized waves are incident on the quad-ridge horn antenna 35, a received signal is output from input / output port 35V and transmitted to input / output port 35H via transmission line 36. As a result, H-polarized waves are output from the quad-ridge horn antenna 35. Similarly, when H-polarized waves are incident on the quad-ridge horn antenna 35, V-polarized waves are output. In this way, the quad-ridge horn antenna 35, with input / output port 35V and input / output port 35H directly connected, can be used as a reflector 30 that converts the polarization of the incident radio waves into orthogonal polarizations and outputs them.

[0051] Next, the excellent effects of the second embodiment will be described. In the second embodiment, as in the first embodiment, it is possible to realize a measurement system with a wide dynamic range. Furthermore, the quad-ridge horn antenna 35 has the characteristic of having a wide operating frequency band. For this reason, in the second embodiment, loopback testing of multiband antenna modules and wideband antenna modules can be performed without having a movable part such as a depth variable mechanism 32 (Figures 6A and 6B) in the reflector 30.

[0052] [Third Embodiment] Next, with reference to Figure 8, the antenna module test apparatus according to the third embodiment will be described. The following description will omit details of components common to the antenna module test apparatus according to the first embodiment, which was described with reference to Figures 1 to 5.

[0053] Figure 8 is a schematic plan view of the reflector 30 of the antenna module test apparatus according to the third embodiment. In the third embodiment, multiple patch antennas are used as the reflector 30. Multiple patch antennas 38 are arranged on one side of the substrate 37. Each of the multiple patch antennas 38 has an input / output port (feed point) 38V for V polarization and an input / output port (feed point) 38H for H polarization. When power is supplied to one input / output port 38V, V polarization is radiated, and when power is supplied to the other input / output port 38H, H polarization is radiated. One input / output port 38V and the other input / output port 38H are connected by a transmission line 39.

[0054] When V-polarized waves are incident on the patch antenna 38, a received signal is output from the V-polarized input / output port 38V and input to the H-polarized input / output port 38H via the transmission line 39. As a result, H-polarized waves are radiated from the patch antenna 38. Similarly, when H-polarized waves are incident on the patch antenna 38, V-polarized waves are radiated. In this way, the patch antenna 38, with one input / output port 38V and the other input / output port 38H directly connected, can be used as a reflector 30 that converts the polarization of the incident radio waves into orthogonal polarizations and outputs them.

[0055] Next, we will describe the excellent effects of the third embodiment. In the third embodiment, as in the first embodiment, it is possible to realize a measurement system with a wide dynamic range.

[0056] [Fourth embodiment] Next, the antenna module test apparatus according to the fourth embodiment will be described with reference to Figures 9A and 9B. The following description will omit details of components common to the antenna module test apparatus according to the first embodiment, which was described with reference to Figures 1 to 5.

[0057] Figure 9A is a cross-sectional view of the antenna module test apparatus and the antenna module 10 to be tested according to the fourth embodiment, and Figure 9B is a cross-sectional view of the antenna module test apparatus and antenna module 10 in a state where a loopback test is being performed. In the first embodiment (Figure 1), the structure for supporting the antenna module 10 and the antenna module test apparatus so that their relative positions are fixed during testing of the antenna module 10 is not specifically shown, but in the fourth embodiment, the structure for fixing their relative positions is made concrete.

[0058] The antenna module test apparatus according to the fourth embodiment includes a socket jig 51, a connector 52, a retaining jig 55, a reflector 30, a first signal processing circuit 40A, and a second signal processing circuit 40B. The antenna module 10 to be tested includes a connector 29 equipped with a first terminal T1 and a second terminal T2. The socket jig 51 has a lateral positioning portion 51A that protrudes from one side of a flat plate portion. The connector 52 is mounted on one side of the flat plate portion of the socket jig 51. The connector 29 of the antenna module 10 and the connector 52 of the socket jig 51 are mated, and the edge of the substrate 28 of the antenna module 10 contacts the lateral positioning portion 51A, thereby positioning and supporting the antenna module 10 on the socket jig 51. In this state, the side on which the radiating element 26 is arranged faces away from the side of the socket jig 51.

[0059] Connector 52 has terminals to which the first signal processing circuit 40A and the second signal processing circuit 40B are connected. When connector 52 is mated with connector 29 of antenna module 10, the first signal processing circuit 40A and the second signal processing circuit 40B are connected to the first terminal T1 and the second terminal T2 of antenna module 10, respectively.

[0060] With the antenna module 10 supported by the socket jig 51, the retaining jig 55 presses the antenna module 10 toward the socket jig 51. The antenna module 10 is stably supported by the socket jig 51 by being pressed by the retaining jig 55. A reflector 30 is attached and fixed to the side of the retaining jig 55 opposite to the side facing the antenna module 10.

[0061] The radio waves emitted from the radiating element 26 pass through the retaining jig 55 and enter the reflector 30. The radio waves reflected by the reflector 30 pass through the retaining jig 55 and enter the radiating element 26. The retaining jig 55 is made of a material that does not hinder the propagation of radio waves, for example, a material with a relative permittivity of 1.1 or less. As an example, polyetheretherketone (PEEK) or the like can be used for the retaining jig 55.

[0062] Next, we will describe the excellent effects of the fourth embodiment. In the fourth embodiment, the positional relationship between the antenna module 10 and the reflector 30 can be kept constant, and variations in their relative positions can be reduced. This ensures high reproducibility in measurements.

[0063] [Fifth Example] Next, the antenna module test apparatus according to the fifth embodiment will be described with reference to Figures 10 and 11. The following description will omit details of components common to the antenna module test apparatus according to the first embodiment, which was described with reference to Figures 1 to 5.

[0064] Figure 10 is a schematic diagram of an antenna module test apparatus according to the fifth embodiment. In the first embodiment (Figure 1), multiple radiating elements 26 are arranged on one planar surface of the substrate 28. In contrast, in the fifth embodiment, the substrate 28 has a curved portion and has one planar first surface 28A and a second surface 28B that is aligned with a plane intersecting the first surface 28A. For example, the first surface 28A and the second surface 28B are oriented in mutually orthogonal directions. Multiple first radiating elements 26A are arranged on the first surface 28A, and multiple second radiating elements 26B are arranged on the second surface 28B. That is, the boresite directions of the multiple first radiating elements 26A and the multiple second radiating elements 26B are different.

[0065] The first signal processing circuit 40A and the second signal processing circuit 40B are connected to the first terminal T1 and the second terminal T2, respectively. The high-frequency signal input to the first terminal T1 is supplied to all first radiating elements 26A and the second radiating elements 26B, and the high-frequency signal input to the second terminal T2 is also supplied to all first radiating elements 26A and the second radiating elements 26B.

[0066] For example, when a high-frequency signal is supplied from the first signal processing circuit 40A to the first radiating element 26A and the second radiating element 26B, V-polarization is emitted. When a high-frequency signal is supplied from the second signal processing circuit 40B to the first radiating element 26A and the second radiating element 26B, H-polarization is emitted.

[0067] A reflector 30 is positioned at each boresite. For example, the first reflector 30A is positioned in the direction of the boresite of the first radiating element 26A, and the second reflector 30B is positioned in the direction of the boresite of the second radiating element 26B. The relationship between the polarization direction of the first radiating element 26A and the first reflector 30A, and the relationship between the polarization direction of the second radiating element 26B and the second reflector 30B are the same as the relationship between the polarization direction of the radiating element 26 and the reflector 30 in the antenna module test apparatus according to the first embodiment.

[0068] Next, the definition of polarization for the antenna module 10 will be explained. Assume that the plane parallel to both the boresite direction of the first radiating element 26A and the boresite direction of the second radiating element 26B is the horizontal plane (the plane parallel to the plane of the paper in Figure 10). A polarization with a polarization plane parallel to this horizontal plane is defined as H polarization, and a polarization with a polarization plane perpendicular to this horizontal plane is defined as V polarization.

[0069] When V-polarized waves are emitted from the first radiating element 26A, H-polarized waves reflected by the first reflector 30A are incident on the first radiating element 26A. Similarly, when V-polarized waves are emitted from the second radiating element 26B, H-polarized waves reflected by the second reflector 30B are incident on the second radiating element 26B.

[0070] As an example, a loopback test of the antenna module 10 is performed by operating the first signal processing circuit 40A as a transmitting circuit and the second signal processing circuit 40B as a receiving circuit.

[0071] Figure 11 is a schematic cross-sectional view specifically showing the structure of an antenna module test apparatus according to the fifth embodiment. The substrate 28 of the antenna module 10 to be tested includes a first rigid portion 28R1 having a first surface 28A on which a plurality of first radiating elements 26A are arranged, a second rigid portion 28R2 having a second surface 28B on which a plurality of second radiating elements 26B are arranged, and a flexible portion 28F connecting the first rigid portion 28R1 and the second rigid portion 29R2. By bending the flexible portion 28F, the boresites of the first radiating elements 26A and the boresites of the second radiating elements 26B face in different directions.

[0072] A recess 51B is formed on one surface of the socket jig 51, and a portion of the first rigid part 28R1 in the thickness direction is positioned within the recess 51B with the first surface 28A of the antenna module 10 facing the bottom surface of the recess 51B. The first rigid part 28R1 is positioned in a direction parallel to the first surface 28A (hereinafter sometimes referred to as the lateral direction) by contacting the side surface of the recess 51B. The side surface of the recess 51B functions as a lateral positioning part 51A for positioning the antenna module 10.

[0073] With the connector 52 on the retaining jig 55 connected to the connector 29 of the antenna module 10, the retaining jig 55 presses the first rigid portion 28R1 against the socket jig 51. This positions and supports the first rigid portion 28R1 on the socket jig 51.

[0074] The first reflector 30A is mounted on the side of the socket jig 51 opposite to the side where the recess 51B is formed. The first reflector 30A faces the first radiating element 26A via the socket jig 51.

[0075] With the first rigid portion 28R1 positioned within the recess 51B, the boresight of the second radiating element 26B faces laterally. Figure 10 shows an example where the boresight direction of the first radiating element 26A and the boresight direction of the second radiating element 26B are orthogonal, but Figure 11 shows an example where they are not orthogonal and the angle between them is greater than 90°. Thus, the boresight direction of the first radiating element 26A and the boresight direction of the second radiating element 26B do not necessarily have to be orthogonal.

[0076] The reflector variable support section 53 is supported by the socket jig 51 so as to be able to move both translationally and rotationally. By moving the reflector variable support section 53 translationally and rotationally, it is possible to position one side of the reflector variable support section 53 facing the second radiating element 26B. The second reflector 30B is attached to the side of the reflector variable support section 53 that is opposite to the side facing the second radiating element 26B. The second reflector 30B faces the second radiating element 26B via the reflector variable support section 53.

[0077] The antenna module 10 is held in the socket jig 51, and the reflector variable support part 53 is moved to the appropriate position to position the first reflector 30A relative to the first radiating element 26A, and the second reflector 30B relative to the second radiating element 26B, thereby performing a loopback test.

[0078] Next, the excellent effects of the fifth embodiment will be described. In the fifth embodiment, it is possible to perform loopback testing of an antenna module 10 equipped with a first radiating element 26A and a second radiating element 26B having different boresite directions. Furthermore, as in the first embodiment, it is possible to ensure a wide dynamic range.

[0079] [Sixth Example] Next, the antenna module test system according to the sixth embodiment will be described with reference to Figures 12 and 13. The following description will omit details of components common to the antenna module test apparatus according to the fifth embodiment, which was described with reference to Figures 10 and 11.

[0080] Figure 12 is a schematic diagram of the antenna module test system according to the sixth embodiment. The antenna module 10 to be tested includes a first radiating element 26A and a second radiating element 26B with different boresite directions, similar to the antenna module 10 to be tested in the antenna module test apparatus according to the fifth embodiment. A first reflector 30A and a second reflector 30B are arranged to face the first radiating element 26A and the second radiating element 26B, respectively.

[0081] Figure 13 is a block diagram of the antenna module test system according to the sixth embodiment. In the first embodiment (Figure 3), the first transmit / receive circuit 21A connected to the first terminal T1 is connected to the first feed point 27A of the radiating element 26, and the second transmit / receive circuit 21B connected to the second terminal T2 is connected to the second feed point 27B of the radiating element 26. In contrast, in the sixth embodiment, the first feed point 27A and the second feed point 27B of the first radiating element 26A are connected to the first transmit / receive circuit 21A and the second transmit / receive circuit 21B, respectively. However, in the second radiating element 26B, the first feed point 27A and the second feed point 27B are connected to the second transmit / receive circuit 21B and the first transmit / receive circuit 21A, respectively. In Figure 13, the feed point connected to the first transmit / receive circuit 21A is shown as a solid circle, and the feed point connected to the second transmit / receive circuit 21B is shown as a hollow circle.

[0082] When a high-frequency signal is supplied from the first signal processing circuit 40A to the first transceiver circuit 21A via the first terminal T1, V-polarized waves are emitted from the first radiating element 26A and H-polarized waves are emitted from the second radiating element 26B. When a high-frequency signal is supplied from the second signal processing circuit 40B to the second transceiver circuit 21B via the second terminal T2, H-polarized waves are emitted from the first radiating element 26A and V-polarized waves are emitted from the second radiating element 26B.

[0083] Thus, with respect to the transmit and receive signals input and output to the first terminal T1, the gain for V polarization in the first radiating element 26A is greater than the gain for H polarization, and the gain for H polarization in the second radiating element 26B is greater than the gain for V polarization. Conversely, with respect to the transmit and receive signals input and output to the second terminal T2, the gain for H polarization in the first radiating element 26A is greater than the gain for V polarization, and the gain for V polarization in the second radiating element 26B is greater than the gain for H polarization.

[0084] Next, we will describe the excellent effects of the sixth embodiment. We will consider the case where the first signal processing circuit 40A is operated as a transmitting circuit and the second signal processing circuit 40B is operated as a receiving circuit to perform a loopback test. As shown in Figure 12, when the first signal processing circuit 40A is operated as a transmitting circuit, V-polarized waves are emitted from the first radiating element 26A and H-polarized waves are emitted from the second radiating element 26B.

[0085] H-polarized waves reflected by the first reflector 30A are incident on the first radiating element 26A, and V-polarized waves reflected by the second reflector 30B are incident on the second radiating element 26B. Because the gain of the second signal processing circuit 40B is large for the H-polarized waves incident on the first radiating element 26A and the V-polarized waves incident on the second radiating element 26B, it is possible to secure a wide dynamic range in the loopback test.

[0086] Furthermore, if the H-polarized wave reflected by the first reflector 30A bends around to the second radiating element 26B and is received, the gain of the second signal processing circuit 40B is small for the H-polarized wave received by the second radiating element 26B. Similarly, if the V-polarized wave reflected by the second reflector 30B bends around to the first radiating element 26A and is received, the gain of the second signal processing circuit 40B is small for the V-polarized wave received by the first radiating element 26A.

[0087] In this way, the transmission and reception of radio waves by the first radiating element 26A and the transmission and reception of radio waves by the second radiating element 26B become less likely to interfere with each other. This makes it possible to improve the accuracy of loopback testing.

[0088] [Seventh Example] Next, the antenna module test apparatus according to the seventh embodiment will be described with reference to Figure 14. The following description will omit details of components common to the antenna module test apparatus according to the first embodiment, which was described with reference to Figures 1 to 5.

[0089] Figure 14 is a block diagram of the antenna module test apparatus and the antenna module 10 to be tested according to the seventh embodiment. In the first embodiment (Figure 3), the radiating element 26 transmits and receives V-polarization and H-polarization as mutually orthogonal polarizations. In contrast, in the seventh embodiment, the antenna module 10 transmits and receives right-hand circular polarization and left-hand circular polarization as mutually orthogonal polarizations.

[0090] A branch-line type hybrid circuit 60 is arranged for each of the radiating elements 26. The high-frequency integrated circuit 25 and the radiating elements 26 are connected via the branch-line type hybrid circuit 60. More specifically, one antenna terminal of the first transceiver circuit 21A is connected to port P1 of the hybrid circuit 60, and one antenna terminal of the second transceiver circuit 21B is connected to port P2 of the hybrid circuit 60.

[0091] Ports P3 and P4 of the hybrid circuit 60 are connected to the first feed point 27A and the second feed point 27B of the radiating element 26, respectively. When a high-frequency signal is input to port P1, high-frequency signals with a 90° phase difference are output from ports P3 and P4. When a high-frequency signal is input to port P2, high-frequency signals with a 90° phase difference are output from ports P3 and P4. The phase lead / lag relationship of the high-frequency signals output from ports P3 and P4 is reversed when the high-frequency signal is input to port P1 compared to when it is input to port P2.

[0092] When a high-frequency signal is supplied from the first signal processing circuit 40A to the hybrid circuit 60 via the first terminal T1 and the first transceiver circuit 21A, right-hand circular polarization is emitted from the radiating element 26. When a high-frequency signal is supplied from the second signal processing circuit 40B to the hybrid circuit 60 via the second terminal T2 and the second transceiver circuit 21B, left-hand circular polarization is emitted from the radiating element 26.

[0093] When a right-hand circularly polarized wave is received by the radiating element 26, a high-frequency signal is output from port P1 of the hybrid circuit 60, and the received signal is input to the first signal processing circuit 40A. When a left-hand circularly polarized wave is received by the radiating element 26, a high-frequency signal is output from port P2 of the hybrid circuit 60, and the received signal is input to the second signal processing circuit 40B. In other words, for the transmit and receive signals input and output to the first terminal T1, the gain of the right-hand circularly polarized wave is greater than the gain of the left-hand circularly polarized wave, and for the transmit and receive signals input and output to the second terminal T2, the gain of the left-hand circularly polarized wave is greater than the gain of the right-hand circularly polarized wave.

[0094] In the seventh embodiment, the same reflector as the reflector 30 of the antenna module test apparatus in the first embodiment (Figures 1 and 2) is used. When a right-hand circularly polarized wave is incident on this reflector 30, the reflected wave becomes left-hand circularly polarized, and when a left-hand circularly polarized wave is incident on it, the reflected wave becomes right-hand circularly polarized. A loopback test is performed by operating one of the first signal processing circuit 40A and the second signal processing circuit 40B as a transmitting circuit and the other as a receiving circuit.

[0095] Next, the excellent effects of the seventh embodiment will be described. In the seventh embodiment, as in the first embodiment, a wide dynamic range can be secured in the loopback test.

[0096] Next, a modified example of the seventh embodiment will be described with reference to Figure 15. Figure 15 is a block diagram of the antenna module test apparatus and the antenna module 10 to be tested according to the modified example of the seventh embodiment. In the seventh embodiment (Figure 14), circular polarization is radiated by supplying a high-frequency signal with a 90° phase difference to the first feed point 27A and the second feed point 27B of a single radiating element 26. In contrast, in the modified example shown in Figure 15, circular polarization is radiated by shaping the radiating element 26 into a square with notches at a pair of opposing vertices.

[0097] For example, when a high-frequency signal is supplied to the first feed point 27A, right-hand circular polarization is radiated, and when a high-frequency signal is supplied to the second feed point 27B, left-hand circular polarization is radiated. The connection configuration between the radiating element 26 and the high-frequency integrated circuit 25 is the same as the connection configuration of the antenna module 10 (Figure 3) that is the subject of testing in the antenna module test apparatus according to the first embodiment. In this modified example, it is possible to perform a loopback test using circular polarization without inserting a hybrid circuit 60 (Figure 14) between the radiating element 26 and the high-frequency integrated circuit 25.

[0098] The embodiments described above are illustrative, and it goes without saying that partial substitution or combination of the configurations shown in different embodiments is possible. Similar effects and benefits from similar configurations in multiple embodiments will not be mentioned sequentially for each embodiment. Furthermore, the present invention is not limited to the embodiments described above. For example, it will be obvious to those skilled in the art that various modifications, improvements, and combinations are possible. [Explanation of Symbols]

[0099] 10 Antenna Modules 11 Amplifier 12 Up / Down Conversion Mixer 13. Transmit / Receive Switch 14 Power Divider 15 Phase shifter 16 Attenuator 17 Transmit / Receive Switch 18 Power Amplifier 19 Low-noise amplifier 20 Transmit / Receive Switch 21A First Transceiver Circuit 21B Second Transceiver Circuit 25. High-Frequency Integrated Circuits (RFICs) 26 Radiation element 26A First radiation component 26B Second Radiating Element 27A First feed point 27B Second power supply point 28 circuit boards 28A First side of the circuit board 28B Second side of the circuit board 28F Flexible section 28R1 1st Rigid Section 28R2 Second Rigid Section 29 Connectors 30 reflector 30A 1st reflector 30B 2nd reflector 30a Groove side component 30b Groove bottom surface component 31 Groove 32 Depth Variable Mechanism 35 Quad-ridge horn antenna 35H Input / Output Port for High Polarization Input / output ports for 35V V polarization 36 Transmission lines 37 circuit boards 38 Patch Antenna 38H Input / Output Ports for High Polarization Input / output ports for 38V V polarization 39 Transmission lines 40 Baseband Integrated Circuits (BBICs) 40A First Signal Processing Circuit 40B Second signal processing circuit 51 Socket jig 51A Lateral positioning section 51B Recess 52 connectors 53 Reflector Variable Indicator 55 Pressing jig 60 Hybrid Circuits T1 First terminal T2 Second terminal

Claims

1. A test apparatus for an antenna module having the function of transmitting and receiving a first polarization and a second polarization that are mutually orthogonal to each other, wherein for the transmit and receive signals input and output to the first terminal, the gain of the first polarization is greater than the gain of the second polarization, and for the transmit and receive signals input and output to the second terminal, the gain of the second polarization is greater than the gain of the first polarization, A reflector is placed at the position where radio waves emitted from the antenna module under test enter, and converts the incident radio waves into a polarization perpendicular to the polarization of the incident radio waves and reflects them back toward the antenna module under test. A first signal processing circuit connected to the first terminal and inputting a transmission signal to the first terminal, A second signal processing circuit connected to the second terminal and processing the received signal output from the second terminal, An antenna module testing device equipped with the following features.

2. The antenna module testing apparatus according to claim 1, wherein the first polarization and the second polarization are linear polarizations with mutually orthogonal polarization planes.

3. The antenna module testing apparatus according to claim 2, wherein a plurality of grooves are formed on the surface of the reflector to which radio waves are incident, extending in a direction that forms an angle of 45° with respect to the polarization plane of the first polarization.

4. The antenna module testing apparatus according to claim 3, wherein the depth of each of the plurality of grooves is 1 / 4 of the wavelength of the radio waves radiated from the antenna module under test.

5. The antenna module testing apparatus according to claim 3, wherein the depth of each of the plurality of grooves is at least one-quarter of the wavelength of the upper limit frequency of the operating frequency band of the antenna module under test, and at least one-quarter of the wavelength of the lower limit frequency.

6. The antenna module testing apparatus according to claim 3, wherein the reflector has a depth variable mechanism for changing the depth of the plurality of grooves.

7. The reflector is, An antenna in which the polarization of the radio waves radiated when power is supplied to one of the two input / output ports and the polarization of the radio waves radiated when power is supplied to the other input / output port are mutually orthogonal, A transmission line connecting one of the two input / output ports to the other. An antenna module testing apparatus according to claim 1 or 2, including the following:

8. moreover, A socket fixture that supports the antenna module under test, Connectors connected to the first terminal and the second terminal, A retaining jig that supports the reflector relative to the socket jig and An antenna module testing apparatus according to claim 1 or 2, comprising:

9. The antenna module under test includes at least two sets of radiating elements with different boresite orientations. The antenna module test apparatus according to claim 1 or 2, wherein the reflector is arranged for each boresite of the radiating element.

10. An antenna module having a first radiating element and a second radiating element with different boresite directions, A first reflector and a second reflector are arranged in the direction of the boresites of the first and second radiating elements, respectively, and convert the incident radio waves into a polarization perpendicular to the polarization of the incident radio waves and reflect them toward the first and second radiating elements. Equipped with, The aforementioned antenna module is First terminal and, The second terminal and, For the transmit and receive signals input and output to the first terminal, the gain of the first radiating element for the first polarization is greater than the gain of the second polarization which is orthogonal to the first polarization, and the gain of the second radiating element for the first polarization is less than the gain of the second polarization. For the transmit and receive signals input and output to the second terminal, the gain of the first radiating element for the second polarization is greater than the gain of the first polarization, and the gain of the second radiating element for the second polarization is less than the gain of the first polarization. A high-frequency integrated circuit that drives the first radiating element and the second radiating element is configured such that, for the transmit and receive signals input and output to the second terminal, the gain of the first radiating element for the second polarization is greater than the gain of the first polarization, and the gain of the second radiating element for the second polarization is less than the gain of the first polarization. Includes, moreover, A first signal processing circuit connected to the first terminal and inputting a transmission signal to the first terminal, A second signal processing circuit connected to the second terminal and processing the received signal output from the second terminal, An antenna module test system equipped with [specific features / equipment].

11. The antenna module under test emits the first polarization, The first polarization radiated from the antenna module is converted to a polarization orthogonal to the first polarization and reflected. The reflected radio waves are received by the antenna module, An antenna module testing method for evaluating the quality of the antenna module based on the reception results.

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